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Lukashchuk A, Yildirim HK, Bancora A, Lihachev G, Liu Y, Qiu Z, Ji X, Voloshin A, Bhave SA, Charbon E, Kippenberg TJ. Photonic-electronic integrated circuit-based coherent LiDAR engine. Nat Commun 2024; 15:3134. [PMID: 38605067 PMCID: PMC11009237 DOI: 10.1038/s41467-024-47478-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 04/02/2024] [Indexed: 04/13/2024] Open
Abstract
Chip-scale integration is a key enabler for the deployment of photonic technologies. Coherent laser ranging or FMCW LiDAR, a perception technology that benefits from instantaneous velocity and distance detection, eye-safe operation, long-range, and immunity to interference. However, wafer-scale integration of these systems has been challenged by stringent requirements on laser coherence, frequency agility, and the necessity for optical amplifiers. Here, we demonstrate a photonic-electronic LiDAR source composed of a micro-electronic-based high-voltage arbitrary waveform generator, a hybrid photonic circuit-based tunable Vernier laser with piezoelectric actuators, and an erbium-doped waveguide amplifier. Importantly, all systems are realized in a wafer-scale manufacturing-compatible process comprising III-V semiconductors, silicon nitride photonic integrated circuits, and 130-nm SiGe bipolar complementary metal-oxide-semiconductor (CMOS) technology. We conducted ranging experiments at a 10-meter distance with a precision level of 10 cm and a 50 kHz acquisition rate. The laser source is turnkey and linearization-free, and it can be seamlessly integrated with existing focal plane and optical phased array LiDAR approaches.
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Affiliation(s)
- Anton Lukashchuk
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Halil Kerim Yildirim
- Advanced Quantum Architecture Laboratory (AQUA), Swiss Federal Institute of Technology Lausanne (EPFL), CH-2002, Neuchâtel, Switzerland
| | - Andrea Bancora
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Grigory Lihachev
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Yang Liu
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Zheru Qiu
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Xinru Ji
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Andrey Voloshin
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | - Sunil A Bhave
- OxideMEMS Lab, Purdue University, 47907, West Lafayette, IN, USA
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory (AQUA), Swiss Federal Institute of Technology Lausanne (EPFL), CH-2002, Neuchâtel, Switzerland.
| | - Tobias J Kippenberg
- Institute of Physics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015, Lausanne, Switzerland.
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Zhou C, Martin OJF, Charbon E. Planar 16-band metasurface-enhanced spectral filter for integrated image sensing. Opt Express 2024; 32:7463-7472. [PMID: 38439425 DOI: 10.1364/oe.515675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 02/02/2024] [Indexed: 03/06/2024]
Abstract
We study theoretically and demonstrate experimentally a 16-band narrow band wavelength selective filter in the near-infrared range. The combination of a pair of distributed Bragg reflectors with a sub-wavelength grating metasurface embedded in the intra-cavity provides a narrow response which can be tuned by adjusting the geometry of the sub-wavelength grating metasurface. The key advantage of this approach is its ease of fabrication, where the spectral response is tuned by merely changing the grating period, resulting in a perfectly planar geometry that can be easily integrated with a broad variety of photodetectors, thus enabling attractive applications such as bio-imaging, time-of-flight sensors and LiDAR. The experimental results are supported by numerical simulations and effective medium theory that unveil the mechanisms that lead to the optical response of the device. It is also shown how the polarization dependence of the structure can be used to determine very accurately the polarization of incoming light.
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Lin Y, Mos P, Ardelean A, Bruschini C, Charbon E. Coupling a recurrent neural network to SPAD TCSPC systems for real-time fluorescence lifetime imaging. Sci Rep 2024; 14:3286. [PMID: 38331957 PMCID: PMC10853568 DOI: 10.1038/s41598-024-52966-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 01/25/2024] [Indexed: 02/10/2024] Open
Abstract
Fluorescence lifetime imaging (FLI) has been receiving increased attention in recent years as a powerful diagnostic technique in biological and medical research. However, existing FLI systems often suffer from a tradeoff between processing speed, accuracy, and robustness. Inspired by the concept of Edge Artificial Intelligence (Edge AI), we propose a robust approach that enables fast FLI with no degradation of accuracy. This approach couples a recurrent neural network (RNN), which is trained to estimate the fluorescence lifetime directly from raw timestamps without building histograms, to SPAD TCSPC systems, thereby drastically reducing transfer data volumes and hardware resource utilization, and enabling real-time FLI acquisition. We train two variants of the RNN on a synthetic dataset and compare the results to those obtained using center-of-mass method (CMM) and least squares fitting (LS fitting). Results demonstrate that two RNN variants, gated recurrent unit (GRU) and long short-term memory (LSTM), are comparable to CMM and LS fitting in terms of accuracy, while outperforming them in the presence of background noise by a large margin. To explore the ultimate limits of the approach, we derive the Cramer-Rao lower bound of the measurement, showing that RNN yields lifetime estimations with near-optimal precision. To demonstrate real-time operation, we build a FLI microscope based on an existing SPAD TCSPC system comprising a 32[Formula: see text]32 SPAD sensor named Piccolo. Four quantized GRU cores, capable of processing up to 4 million photons per second, are deployed on the Xilinx Kintex-7 FPGA that controls the Piccolo. Powered by the GRU, the FLI setup can retrieve real-time fluorescence lifetime images at up to 10 frames per second. The proposed FLI system is promising and ideally suited for biomedical applications, including biological imaging, biomedical diagnostics, and fluorescence-assisted surgery, etc.
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Affiliation(s)
- Yang Lin
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Neuchâtel, 2002, Switzerland
| | - Paul Mos
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Neuchâtel, 2002, Switzerland
| | - Andrei Ardelean
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Neuchâtel, 2002, Switzerland
| | - Claudio Bruschini
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Neuchâtel, 2002, Switzerland
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Neuchâtel, 2002, Switzerland.
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Petusseau AF, Streeter SS, Ulku A, Feng Y, Samkoe KS, Bruschini C, Charbon E, Pogue BW, Bruza P. Subsurface fluorescence time-of-flight imaging using a large-format single-photon avalanche diode sensor for tumor depth assessment. J Biomed Opt 2024; 29:016004. [PMID: 38235320 PMCID: PMC10794045 DOI: 10.1117/1.jbo.29.1.016004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 12/06/2023] [Accepted: 12/20/2023] [Indexed: 01/19/2024]
Abstract
Significance Fluorescence guidance is used clinically by surgeons to visualize anatomical and/or physiological phenomena in the surgical field that are difficult or impossible to detect by the naked eye. Such phenomena include tissue perfusion or molecular phenotypic information about the disease being resected. Conventional fluorescence-guided surgery relies on long, microsecond scale laser pulses to excite fluorescent probes. However, this technique only provides two-dimensional information; crucial depth information, such as the location of malignancy below the tissue surface, is not provided. Aim We developed a depth sensing imaging technique using light detection and ranging (LiDAR) time-of-flight (TOF) technology to sense the depth of target tissue while overcoming the influence of tissue optical properties and fluorescent probe concentration. Approach The technology is based on a large-format (512 × 512 pixel ), binary, gated, single-photon avalanche diode (SPAD) sensor with an 18 ps time-gate step, synchronized with a picosecond pulsed laser. The fast response of the sensor was developed and tested for its ability to quantify fluorescent inclusions at depth and optical properties in tissue-like phantoms through analytical model fitting of the fast temporal remission data. Results After calibration and algorithmic extraction of the data, the SPAD LiDAR technique allowed for sub-mm resolution depth sensing of fluorescent inclusions embedded in tissue-like phantoms, up to a maximum of 5 mm in depth. The approach provides robust depth sensing even in the presence of variable tissue optical properties and separates the effects of fluorescence depth from absorption and scattering variations. Conclusions LiDAR TOF fluorescence imaging using an SPAD camera provides both fluorescence intensity images and the temporal profile of fluorescence, which can be used to determine the depth at which the signal is emitted over a wide field of view. The proposed tool enables fluorescence imaging at a higher depth in tissue and with higher spatial precision than standard, steady-state fluorescence imaging tools, such as intensity-based near-infrared fluorescence imaging, optical coherence tomography, Raman spectroscopy, or confocal microscopy. Integration of this technique into a standard surgical tool could enable rapid, more accurate estimation of resection boundaries, thereby improving the surgeon's efficacy and efficiency, and ultimately improving patient outcomes.
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Affiliation(s)
- Arthur F Petusseau
- Dartmouth College, Thayer School of Engineering and Dartmouth Cancer Center, Hanover, New Hampshire, United States
| | - Samuel S Streeter
- Geisel School of Medicine at Dartmouth, Department of Orthopaedics, Hanover, New Hampshire, United States
| | - Arin Ulku
- Ecole polytechnique fédérale de Lausanne, Advanced Quantum Architecture Laboratory, Neuchâtel, Switzerland
| | - Yichen Feng
- Geisel School of Medicine at Dartmouth, Department of Surgery, Hanover, New Hampshire, United States
| | - Kimberley S Samkoe
- Geisel School of Medicine at Dartmouth, Department of Surgery, Hanover, New Hampshire, United States
| | - Claudio Bruschini
- Ecole polytechnique fédérale de Lausanne, Advanced Quantum Architecture Laboratory, Neuchâtel, Switzerland
| | - Edoardo Charbon
- Ecole polytechnique fédérale de Lausanne, Advanced Quantum Architecture Laboratory, Neuchâtel, Switzerland
| | - Brian W Pogue
- Dartmouth College, Thayer School of Engineering and Dartmouth Cancer Center, Hanover, New Hampshire, United States
- University of Wisconsin-Madison, Department of Medical Physics, Madison, Wisconsin, United States
| | - Petr Bruza
- Dartmouth College, Thayer School of Engineering and Dartmouth Cancer Center, Hanover, New Hampshire, United States
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Milanese T, Bruschini C, Burri S, Bernasconi E, Ulku AC, Charbon E. LinoSPAD2: an FPGA-based, hardware-reconfigurable 512×1 single-photon camera system. Opt Express 2023; 31:44295-44314. [PMID: 38178504 DOI: 10.1364/oe.505748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/26/2023] [Indexed: 01/06/2024]
Abstract
We report on LinoSPAD2, a single-photon camera system, comprising a 512×1 single-photon avalanche diode (SPAD) front-end and one or two FPGA-based back-ends. Digital signals generated by the SPADs are processed by the FPGA in real time, whereas the FPGA offers full reconfigurability at a very high level of granularity both in time and space domains. The LinoSPAD2 camera system can process 512 SPADs simultaneously through 256 channels, duplicated on each FPGA-based back-end, with a bank of 64 time-to-digital converters (TDCs) operating at 133 MSa/s, whereas each TDC has a time resolution of 20 ps (LSB). To the best of our knowledge, LinoSPAD2 is the first fully reconfigurable SPAD camera system of large format. The SPAD front-end features a pitch of 26.2 μm, a native fill factor of 25.1%, and a microlens array achieving 2.3× concentration factor. At room temperature, the median dark count rate (DCR) is 80 cps at 7 V excess bias, the peak photon detection probability (PDP) is 53% at 520 nm wavelength, and the single-photon timing resolution (SPTR) is 50 ps FWHM. The instrument response function (IRF) is around 100 ps FWHM at system level. The LinoSPAD2 camera system is suitable for numerous applications, including LiDAR imaging, heralded spectroscopy, compressive Raman sensing, and other computational imaging techniques.
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Strauß M, Shayeghi A, Mauser MF, Geyer P, Kostersitz T, Salapa J, Dobrovolskiy O, Daly S, Commandeur J, Hua Y, Köhler V, Mayor M, Benserhir J, Bruschini C, Charbon E, Castaneda M, Gevers M, Gourgues R, Kalhor N, Fognini A, Arndt M. Highly sensitive single-molecule detection of macromolecule ion beams. Sci Adv 2023; 9:eadj2801. [PMID: 38039360 PMCID: PMC10691769 DOI: 10.1126/sciadv.adj2801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 11/02/2023] [Indexed: 12/03/2023]
Abstract
The analysis of proteins in the gas phase benefits from detectors that exhibit high efficiency and precise spatial resolution. Although modern secondary electron multipliers already address numerous analytical requirements, additional methods are desired for macromolecules at energies lower than currently used in post-acceleration detection. Previous studies have proven the sensitivity of superconducting detectors to high-energy particles in time-of-flight mass spectrometry. Here, we demonstrate that superconducting nanowire detectors are exceptionally well suited for quadrupole mass spectrometry and exhibit an outstanding quantum yield at low-impact energies. At energies as low as 100 eV, the sensitivity of these detectors surpasses conventional ion detectors by three orders of magnitude, and they offer the possibility to discriminate molecules by their impact energy and charge. We demonstrate three developments with these compact and sensitive devices, the recording of 2D ion beam profiles, photochemistry experiments in the gas phase, and advanced cryogenic electronics to pave the way toward highly integrated detectors.
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Affiliation(s)
- Marcel Strauß
- Faculty of Physics and Vienna Doctoral School of Physics (VDSP) and Vienna Center for Quantum Science and Technology (VCQ), University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Armin Shayeghi
- Faculty of Physics and Vienna Doctoral School of Physics (VDSP) and Vienna Center for Quantum Science and Technology (VCQ), University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
- Institute for Quantum Optics and Quantum Information (IQOQI) Vienna, Austrian Academy of Sciences, Boltzmanngasse 3, A-1090 Vienna, Austria
| | - Martin F. X. Mauser
- Faculty of Physics and Vienna Doctoral School of Physics (VDSP) and Vienna Center for Quantum Science and Technology (VCQ), University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Philipp Geyer
- Faculty of Physics and Vienna Doctoral School of Physics (VDSP) and Vienna Center for Quantum Science and Technology (VCQ), University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Tim Kostersitz
- Faculty of Physics and Vienna Doctoral School of Physics (VDSP) and Vienna Center for Quantum Science and Technology (VCQ), University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Julia Salapa
- Faculty of Physics and Vienna Doctoral School of Physics (VDSP) and Vienna Center for Quantum Science and Technology (VCQ), University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Oleksandr Dobrovolskiy
- Faculty of Physics and Vienna Doctoral School of Physics (VDSP) and Vienna Center for Quantum Science and Technology (VCQ), University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Steven Daly
- MSVision, Televisieweg 40, 1322 AM Almere, The Netherlands
| | - Jan Commandeur
- MSVision, Televisieweg 40, 1322 AM Almere, The Netherlands
| | - Yong Hua
- Department of Chemistry, University of Basel, St. Johannsring 19, CH-4056 Basel, Switzerland
| | - Valentin Köhler
- Department of Chemistry, University of Basel, St. Johannsring 19, CH-4056 Basel, Switzerland
| | - Marcel Mayor
- Department of Chemistry, University of Basel, St. Johannsring 19, CH-4056 Basel, Switzerland
| | - Jad Benserhir
- Advanced Quantum Architecture Laboratory, EPFL, Rue de la Maladière 71b, CH-2002 Neuchâtel, Switzerland
| | - Claudio Bruschini
- Advanced Quantum Architecture Laboratory, EPFL, Rue de la Maladière 71b, CH-2002 Neuchâtel, Switzerland
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, EPFL, Rue de la Maladière 71b, CH-2002 Neuchâtel, Switzerland
| | - Mario Castaneda
- Single Quantum, Rotterdamseweg 394, 2629 HH, Delft, The Netherlands
| | - Monique Gevers
- Single Quantum, Rotterdamseweg 394, 2629 HH, Delft, The Netherlands
| | - Ronan Gourgues
- Single Quantum, Rotterdamseweg 394, 2629 HH, Delft, The Netherlands
| | - Nima Kalhor
- Single Quantum, Rotterdamseweg 394, 2629 HH, Delft, The Netherlands
| | - Andreas Fognini
- Single Quantum, Rotterdamseweg 394, 2629 HH, Delft, The Netherlands
| | - Markus Arndt
- Faculty of Physics and Vienna Doctoral School of Physics (VDSP) and Vienna Center for Quantum Science and Technology (VCQ), University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
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Massaro G, Mos P, Vasiukov S, Di Lena F, Scattarella F, Pepe FV, Ulku A, Giannella D, Charbon E, Bruschini C, D'Angelo M. Correlated-photon imaging at 10 volumetric images per second. Sci Rep 2023; 13:12813. [PMID: 37550319 PMCID: PMC10406932 DOI: 10.1038/s41598-023-39416-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 07/25/2023] [Indexed: 08/09/2023] Open
Abstract
The correlation properties of light provide an outstanding tool to overcome the limitations of traditional imaging techniques. A relevant case is represented by correlation plenoptic imaging (CPI), a quantum-inspired volumetric imaging protocol employing spatio-temporally correlated photons from either entangled or chaotic sources to address the main limitations of conventional light-field imaging, namely, the poor spatial resolution and the reduced change of perspective for 3D imaging. However, the application potential of high-resolution imaging modalities relying on photon correlations is limited, in practice, by the need to collect a large number of frames. This creates a gap, unacceptable for many relevant tasks, between the time performance of correlated-light imaging and that of traditional imaging methods. In this article, we address this issue by exploiting the photon number correlations intrinsic in chaotic light, combined with a cutting-edge ultrafast sensor made of a large array of single-photon avalanche diodes (SPADs). This combination of source and sensor is embedded within a novel single-lens CPI scheme enabling to acquire 10 volumetric images per second. Our results place correlated-photon imaging at a competitive edge and prove its potential in practical applications.
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Affiliation(s)
- Gianlorenzo Massaro
- Dipartimento Interuniversitario di Fisica, Università degli studi di Bari, 70126, Bari, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Bari, 70125, Bari, Italy
| | - Paul Mos
- Ecole polytechnique fédérale de Lausanne (EPFL), 2002, Neuchâtel, Switzerland
| | - Sergii Vasiukov
- Istituto Nazionale di Fisica Nucleare, Sezione di Bari, 70125, Bari, Italy
| | - Francesco Di Lena
- Istituto Nazionale di Fisica Nucleare, Sezione di Bari, 70125, Bari, Italy
| | - Francesco Scattarella
- Dipartimento Interuniversitario di Fisica, Università degli studi di Bari, 70126, Bari, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Bari, 70125, Bari, Italy
| | - Francesco V Pepe
- Dipartimento Interuniversitario di Fisica, Università degli studi di Bari, 70126, Bari, Italy.
- Istituto Nazionale di Fisica Nucleare, Sezione di Bari, 70125, Bari, Italy.
| | - Arin Ulku
- Ecole polytechnique fédérale de Lausanne (EPFL), 2002, Neuchâtel, Switzerland
| | - Davide Giannella
- Dipartimento Interuniversitario di Fisica, Università degli studi di Bari, 70126, Bari, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Bari, 70125, Bari, Italy
| | - Edoardo Charbon
- Ecole polytechnique fédérale de Lausanne (EPFL), 2002, Neuchâtel, Switzerland
| | - Claudio Bruschini
- Ecole polytechnique fédérale de Lausanne (EPFL), 2002, Neuchâtel, Switzerland
| | - Milena D'Angelo
- Dipartimento Interuniversitario di Fisica, Università degli studi di Bari, 70126, Bari, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Bari, 70125, Bari, Italy
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Bruschini C, Antolovic IM, Zanella F, Ulku AC, Lindner S, Kalyanov A, Milanese T, Bernasconi E, Pešić V, Charbon E. Challenges and prospects for multi-chip microlens imprints on front-side illuminated SPAD imagers. Opt Express 2023; 31:21935-21953. [PMID: 37381279 DOI: 10.1364/oe.488177] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 06/01/2023] [Indexed: 06/30/2023]
Abstract
The overall sensitivity of frontside-illuminated, silicon single-photon avalanche diode (SPAD) arrays has often suffered from fill factor limitations. The fill factor loss can however be recovered by employing microlenses, whereby the challenges specific to SPAD arrays are represented by large pixel pitch (> 10 µm), low native fill factor (as low as ∼10%), and large size (up to 10 mm). In this work we report on the implementation of refractive microlenses by means of photoresist masters, used to fabricate molds for imprints of UV curable hybrid polymers deposited on SPAD arrays. Replications were successfully carried out for the first time, to the best of our knowledge, at wafer reticle level on different designs in the same technology and on single large SPAD arrays with very thin residual layers (∼10 µm), as needed for better efficiency at higher numerical aperture (NA > 0.25). In general, concentration factors within 15-20% of the simulation results were obtained for the smaller arrays (32×32 and 512×1), achieving for example an effective fill factor of 75.6-83.2% for a 28.5 µm pixel pitch with a native fill factor of 28%. A concentration factor up to 4.2 was measured on large 512×512 arrays with a pixel pitch of 16.38 µm and a native fill factor of 10.5%, whereas improved simulation tools could give a better estimate of the actual concentration factor. Spectral measurements were also carried out, resulting in good and uniform transmission in the visible and NIR.
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Ma Y, Huang L, Sen C, Burri S, Bruschini C, Yang X, Cameron RB, Fishbein GA, Gomperts BN, Ozcan A, Charbon E, Gao L. Light-field tomographic fluorescence lifetime imaging microscopy. Res Sq 2023:rs.3.rs-2883279. [PMID: 37214842 PMCID: PMC10197779 DOI: 10.21203/rs.3.rs-2883279/v1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Fluorescence lifetime imaging microscopy (FLIM) is a powerful imaging technique that enables the visualization of biological samples at the molecular level by measuring the fluorescence decay rate of fluorescent probes. This provides critical information about molecular interactions, environmental changes, and localization within biological systems. However, creating high-resolution lifetime maps using conventional FLIM systems can be challenging, as it often requires extensive scanning that can significantly lengthen acquisition times. This issue is further compounded in three-dimensional (3D) imaging because it demands additional scanning along the depth axis. To tackle this challenge, we developed a novel computational imaging technique called light field tomographic FLIM (LIFT-FLIM). Our approach allows for the acquisition of volumetric fluorescence lifetime images in a highly data-efficient manner, significantly reducing the number of scanning steps required compared to conventional point-scanning or line-scanning FLIM imagers. Moreover, LIFT-FLIM enables the measurement of high-dimensional data using low-dimensional detectors, which are typically low-cost and feature a higher temporal bandwidth. We demonstrated LIFT-FLIM using a linear single-photon avalanche diode array on various biological systems, showcasing unparalleled single-photon detection sensitivity. Additionally, we expanded the functionality of our method to spectral FLIM and demonstrated its application in high-content multiplexed imaging of lung organoids. LIFT-FLIM has the potential to open up new avenues in both basic and translational biomedical research.
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Affiliation(s)
- Yayao Ma
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - Luzhe Huang
- Department of Bioengineering, University of California, Los Angeles, CA, USA
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA, USA
- California Nano Systems Institute, University of California, Los Angeles, CA, USA
| | - Chandani Sen
- UCLA Children’s Discovery and Innovation Institute, Mattel Children’s Hospital UCLA, Department of Pediatrics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Samuel Burri
- Advanced Quantum Architecture Laboratory, Ecole Polytechnique Federale de Lausanne, Neuchatel, Switzerland
| | - Claudio Bruschini
- Advanced Quantum Architecture Laboratory, Ecole Polytechnique Federale de Lausanne, Neuchatel, Switzerland
| | - Xilin Yang
- Department of Bioengineering, University of California, Los Angeles, CA, USA
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA, USA
- California Nano Systems Institute, University of California, Los Angeles, CA, USA
| | - Robert B. Cameron
- Department of Thoracic Surgery, University of California, Los Angeles, CA, USA
| | - Gregory A. Fishbein
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Brigitte N. Gomperts
- UCLA Children’s Discovery and Innovation Institute, Mattel Children’s Hospital UCLA, Department of Pediatrics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Aydogan Ozcan
- Department of Bioengineering, University of California, Los Angeles, CA, USA
- Electrical and Computer Engineering Department, University of California, Los Angeles, CA, USA
- California Nano Systems Institute, University of California, Los Angeles, CA, USA
- David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, Ecole Polytechnique Federale de Lausanne, Neuchatel, Switzerland
| | - Liang Gao
- Department of Bioengineering, University of California, Los Angeles, CA, USA
- California Nano Systems Institute, University of California, Los Angeles, CA, USA
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Ha WY, Park E, Eom D, Park HS, Chong D, Tan SS, Tng M, Quek E, Bruschini C, Charbon E, Choi WY, Lee MJ. Single-photon avalanche diode fabricated in standard 55 nm bipolar-CMOS-DMOS technology with sub-20 V breakdown voltage. Opt Express 2023; 31:13798-13805. [PMID: 37157258 DOI: 10.1364/oe.485424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
This paper presents a single-photon avalanche diode (SPAD) in 55 nm bipolar-CMOS-DMOS (BCD) technology. In order to realize a SPAD having sub-20 V breakdown voltage for mobile applications while preventing high tunneling noise, a high-voltage N-well available in BCD is utilized to implement the avalanche multiplication region. The resulting SPAD has a breakdown voltage of 18.4 V while achieving an excellent dark count rate of 4.4 cps/µm2 at the excess bias voltage of 7 V in spite of the advanced technology node. At the same time, the device achieves a high peak photon detection probability (PDP) of 70.1% at 450 nm thanks to the high and uniform E-field. Its PDP values at 850 and 940 nm, wavelengths of interest for 3D ranging applications reach 7.2 and 3.1%, respectively, with the use of deep N-well. The timing jitter of the SPAD, full width at half maximum (FWHM), is 91 ps at 850 nm. It is expected that the presented SPAD enables cost-effective time-of-flight and LiDAR sensors with the advanced standard technology for many mobile applications.
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11
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Roy D, Michalet X, Bharadwaj K, Miller EW, Wang Y, Deb A, Wayne MA, Bruschini C, Charbon E, Vakili M, Gunsalus R, Clubb RT, Weiss S. Towards precise optical measurements of steady state of and small changes in resting membrane potentials. Biophys J 2023; 122:176a. [PMID: 36782833 DOI: 10.1016/j.bpj.2022.11.1096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Affiliation(s)
- Debjit Roy
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Xavier Michalet
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Kiran Bharadwaj
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Evan W Miller
- Department of Chemistry, University of California Berkeley, Berkeley, CA, USA
| | - Yijie Wang
- Department of Medicine and Molecular Cell and Developmental Biology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Arjun Deb
- Department of Medicine and Molecular Cell and Developmental Biology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Michael A Wayne
- School of Engineering, Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Claudio Bruschini
- School of Engineering, Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Edoardo Charbon
- School of Engineering, Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Mahbanoo Vakili
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Robert Gunsalus
- Department of Microbiology, Immunology and Molecular Genetics, University of California Los Angeles, Los Angeles, CA, USA
| | - Robert T Clubb
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Shimon Weiss
- Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, USA
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12
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Wayne MA, Sie EJ, Ulku AC, Mos P, Ardelean A, Marsili F, Bruschini C, Charbon E. Massively parallel, real-time multispeckle diffuse correlation spectroscopy using a 500 × 500 SPAD camera. Biomed Opt Express 2023; 14:703-713. [PMID: 36874503 PMCID: PMC9979680 DOI: 10.1364/boe.473992] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 12/01/2022] [Accepted: 12/24/2022] [Indexed: 06/02/2023]
Abstract
Diffuse correlation spectroscopy (DCS) is a promising noninvasive technique for monitoring cerebral blood flow and measuring cortex functional activation tasks. Taking multiple parallel measurements has been shown to increase sensitivity, but is not easily scalable with discrete optical detectors. Here we show that with a large 500 × 500 SPAD array and an advanced FPGA design, we achieve an SNR gain of almost 500 over single-pixel mDCS performance. The system can also be reconfigured to sacrifice SNR to decrease correlation bin width, with 400 ns resolution being demonstrated over 8000 pixels.
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Affiliation(s)
- Michael A. Wayne
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Rue de la Maladière 71B, Neuchatel, NE 2000, Switzerland
| | - Edbert J. Sie
- Reality Labs Research, Meta Platforms Inc., Menlo Park, CA 94025, USA
| | - Arin C. Ulku
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Rue de la Maladière 71B, Neuchatel, NE 2000, Switzerland
| | - Paul Mos
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Rue de la Maladière 71B, Neuchatel, NE 2000, Switzerland
| | - Andrei Ardelean
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Rue de la Maladière 71B, Neuchatel, NE 2000, Switzerland
| | - Francesco Marsili
- Reality Labs Research, Meta Platforms Inc., Menlo Park, CA 94025, USA
| | - Claudio Bruschini
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Rue de la Maladière 71B, Neuchatel, NE 2000, Switzerland
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, École polytechnique fédérale de Lausanne, Rue de la Maladière 71B, Neuchatel, NE 2000, Switzerland
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13
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Xue X, Hart P', Charbon E, Sebastiano F, Vladimirescu A. Nano-MOSFET – Foundation of Quantum Computing Part I. IEEE Nanotechnology Mag 2023. [DOI: 10.1109/mnano.2022.3228097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Xiao Xue
- Delft University of Technology, Delft, Netherlands
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14
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Michalet X, Ulku AC, Wayne MA, Weiss S, Bruschini C, Charbon E. NIR Fluorescence lifetime macroscopic imaging with a novel time-gated SPAD camera. Proc SPIE Int Soc Opt Eng 2023; 12384:1238409. [PMID: 37869412 PMCID: PMC10586139 DOI: 10.1117/12.2649227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2023]
Abstract
SwissSPAD3 is the latest of a family of widefield time-gated SPAD imagers developed for fluorescence lifetime imaging (FLI) applications. Its distinctive features are (i) the ability to define shorter gates than its predecessors (width W < 1 ns), (ii) support for laser repetition rates up to at least 80 MHz and (iii) a dual-gate architecture providing an effective duty cycle of 100%. We present widefield macroscopic FLI measurements of short lifetime NIR dyes, analyzed using the phasor approach. The results are compared with those previously obtained with SwissSPAD2 and to theoretical predictions.
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Affiliation(s)
- Xavier Michalet
- Department of Chemistry & Biochemistry, UCLA, Los Angeles, CA, USA 90095
| | - Arin C. Ulku
- AQUA Lab, Ecole polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Michael A. Wayne
- AQUA Lab, Ecole polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Shimon Weiss
- Department of Chemistry & Biochemistry, UCLA, Los Angeles, CA, USA 90095
| | - Claudio Bruschini
- AQUA Lab, Ecole polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Edoardo Charbon
- AQUA Lab, Ecole polytechnique fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
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15
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Jiang J, Ackermann M, Russomanno E, Di Costanzo Mata A, Charbon E, Wolf M, Kalyanov A. Resolution and penetration depth of reflection-mode time-domain near infrared optical tomography using a ToF SPAD camera. Biomed Opt Express 2022; 13:6711-6723. [PMID: 36589570 PMCID: PMC9774846 DOI: 10.1364/boe.470985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 09/29/2022] [Accepted: 09/29/2022] [Indexed: 06/17/2023]
Abstract
In a turbid medium such as biological tissue, near-infrared optical tomography (NIROT) can image the oxygenation, a highly relevant clinical parameter. To be an efficient diagnostic tool, NIROT has to have high spatial resolution and depth sensitivity, fast acquisition time, and be easy to use. Since many tissues cannot be penetrated by near-infrared light, such tissue needs to be measured in reflection mode, i.e., where light emission and detection components are placed on the same side. Thanks to the recent advance in single-photon avalanche diode (SPAD) array technology, we have developed a compact reflection-mode time-domain (TD) NIROT system with a large number of channels, which is expected to substantially increase the resolution and depth sensitivity of the oxygenation images. The aim was to test this experimentally for our SPAD camera-empowered TD NIROT system. Experiments with one and two inclusions, i.e., optically dense spheres of 5mm radius, immersed in turbid liquid were conducted. The inclusions were placed at depths from 10mm to 30mm and moved across the field-of-view. In the two-inclusion experiment, two identical spheres were placed at a lateral distance of 8mm. We also compared short exposure times of 1s, suitable for dynamic processes, with a long exposure of 100s. Additionally, we imaged complex geometries inside the turbid medium, which represented structural elements of a biological object. The quality of the reconstructed images was quantified by the root mean squared error (RMSE), peak signal-to-noise ratio (PSNR), and dice similarity. The two small spheres were successfully resolved up to a depth of 30mm. We demonstrated robust image reconstruction even at 1s exposure. Furthermore, the complex geometries were also successfully reconstructed. The results demonstrated a groundbreaking level of enhanced performance of the NIROT system based on a SPAD camera.
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Affiliation(s)
- Jingjing Jiang
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
| | - Meret Ackermann
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
| | - Emanuele Russomanno
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
| | - Aldo Di Costanzo Mata
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, EPFL, 2002 Neuchâtel, Switzerland
| | - Martin Wolf
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
| | - Alexander Kalyanov
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
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16
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Smith JT, Rudkouskaya A, Gao S, Gupta JM, Ulku A, Bruschini C, Charbon E, Weiss S, Barroso M, Intes X, Michalet X. In vitro and in vivo NIR fluorescence lifetime imaging with a time-gated SPAD camera. Optica 2022; 9:532-544. [PMID: 35968259 PMCID: PMC9368735 DOI: 10.1364/optica.454790] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/27/2022] [Indexed: 05/20/2023]
Abstract
Near-infrared (NIR) fluorescence lifetime imaging (FLI) provides a unique contrast mechanism to monitor biological parameters and molecular events in vivo. Single-photon avalanche diode (SPAD) cameras have been recently demonstrated in FLI microscopy (FLIM) applications, but their suitability for in vivo macroscopic FLI (MFLI) in deep tissues remains to be demonstrated. Herein, we report in vivo NIR MFLI measurement with SwissSPAD2, a large time-gated SPAD camera. We first benchmark its performance in well-controlled in vitro experiments, ranging from monitoring environmental effects on fluorescence lifetime, to quantifying Förster resonant energy transfer (FRET) between dyes. Next, we use it for in vivo studies of target-drug engagement in live and intact tumor xenografts using FRET. Information obtained with SwissSPAD2 was successfully compared to that obtained with a gated intensified charge-coupled device (ICCD) camera, using two different approaches. Our results demonstrate that SPAD cameras offer a powerful technology for in vivo preclinical applications in the NIR window.
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Affiliation(s)
- Jason T. Smith
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
| | - Alena Rudkouskaya
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York 12208, USA
| | - Shan Gao
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
| | - Juhi M. Gupta
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
| | - Arin Ulku
- AQUA Lab, Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Claudio Bruschini
- AQUA Lab, Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Edoardo Charbon
- AQUA Lab, Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - Shimon Weiss
- Department of Chemistry & Biochemistry, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Margarida Barroso
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York 12208, USA
| | - Xavier Intes
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA
| | - Xavier Michalet
- Department of Chemistry & Biochemistry, University of California at Los Angeles, Los Angeles, California 90095, USA
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17
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Wu ML, Ripiccini E, Kizilkan E, Gramuglia F, Keshavarzian P, Fenoglio CA, Morimoto K, Charbon E. Radiation Hardness Study of Single-Photon Avalanche Diode for Space and High Energy Physics Applications. Sensors (Basel) 2022; 22:s22082919. [PMID: 35458904 PMCID: PMC9025377 DOI: 10.3390/s22082919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/07/2022] [Accepted: 04/08/2022] [Indexed: 02/04/2023]
Abstract
The radiation hardness of 180 nm complementary metal-oxide-semiconductor (CMOS) and 55 nm bipolar-CMOS-double-diffused MOS single-photon avalanche diodes (SPADs) is studied using 10 MeV and 100 MeV protons up to a displacement damage dose of 1 PeV/g. It is found that the dark count rate (DCR) levels are dependent on the number and the type of defects created. A new stepwise increase in the DCR is presented. Afterpulsing was found to be a significant contributor to the observed DCR increase. A new model for DCR increase prediction is proposed considering afterpulsing. Most of the samples under test retain reasonable DCR levels after irradiation, showing high tolerance to ionizing and displacement damage caused by protons. Following irradiation, self-healing was observed at room temperature. Furthermore, high-temperature annealing shows potential for accelerating recovery. Overall, the results show the suitability of SPADs as optical detectors for long-term space missions or as detectors for high-energy particles.
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Affiliation(s)
- Ming-Lo Wu
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2002 Neuchâtel, Switzerland; (E.R.); (E.K.); (F.G.); (P.K.); (C.A.F.)
- Correspondence: (M.-L.W.); (E.C.)
| | - Emanuele Ripiccini
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2002 Neuchâtel, Switzerland; (E.R.); (E.K.); (F.G.); (P.K.); (C.A.F.)
| | - Ekin Kizilkan
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2002 Neuchâtel, Switzerland; (E.R.); (E.K.); (F.G.); (P.K.); (C.A.F.)
| | - Francesco Gramuglia
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2002 Neuchâtel, Switzerland; (E.R.); (E.K.); (F.G.); (P.K.); (C.A.F.)
| | - Pouyan Keshavarzian
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2002 Neuchâtel, Switzerland; (E.R.); (E.K.); (F.G.); (P.K.); (C.A.F.)
| | - Carlo Alberto Fenoglio
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2002 Neuchâtel, Switzerland; (E.R.); (E.K.); (F.G.); (P.K.); (C.A.F.)
| | | | - Edoardo Charbon
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2002 Neuchâtel, Switzerland; (E.R.); (E.K.); (F.G.); (P.K.); (C.A.F.)
- Correspondence: (M.-L.W.); (E.C.)
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18
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Zhao J, Lyons A, Ulku AC, Defienne H, Faccio D, Charbon E. Light detection and ranging with entangled photons. Opt Express 2022; 30:3675-3683. [PMID: 35209621 DOI: 10.1364/oe.435898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 01/08/2022] [Indexed: 06/14/2023]
Abstract
Single-photon light detection and ranging (LiDAR) is a key technology for depth imaging through complex environments. Despite recent advances, an open challenge is the ability to isolate the LiDAR signal from other spurious sources including background light and jamming signals. Here we show that a time-resolved coincidence scheme can address these challenges by exploiting spatio-temporal correlations between entangled photon pairs. We demonstrate that a photon-pair-based LiDAR can distill desired depth information in the presence of both synchronous and asynchronous spurious signals without prior knowledge of the scene and the target object. This result enables the development of robust and secure quantum LiDAR systems and paves the way to time-resolved quantum imaging applications.
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19
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Michalet X, Ulku A, Smith J, Bruschini C, Weiss S, Charbon E, Intes X. NIR Fluorescence lifetime macroscopic imaging with a time-gated SPAD camera. Proc SPIE Int Soc Opt Eng 2022; 11965:1196507. [PMID: 35992190 PMCID: PMC9385163 DOI: 10.1117/12.2607833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The performance of SwissSPAD2 (SS2), a large scale, widefield time-gated CMOS SPAD imager developed for fluorescence lifetime imaging, has recently been described in the context of visible range and fluorescence lifetime imaging microscopy (FLIM) of dyes with lifetimes in the 2.5 - 4 ns range. Here, we explore its capabilities in the NIR regime relevant for small animal imaging, where its sensitivity is lower and typical NIR fluorescent dye lifetimes are much shorter (1 ns or less). We carry out this study in a simple macroscopic imaging setup based on a compact NIR picosecond pulsed laser, an engineered diffuser-based illumination optics, and NIR optimized imaging lens suitable for well-plate or small animal imaging. Because laser repetition rates can vary between models, but the synchronization signal frequency accepted by SS2 is fixed to 20 MHz, we first checked that a simple frequency-division scheme enables data recording for different laser repetition rates. Next, we acquired data using different time gate widths, including gates with duration longer than the laser period, and analyzed the resulting data using both standard nonlinear least-square fit (NLSF) and phasor analysis. We show that the fixed synchronization rate and large gate widths characterizing SS2 (10 ns and over) are not an obstacle to accurately extracting lifetime in the 1 ns range and to distinguishing between close lifetimes. In summary, SS2 and similar very large gated SPAD imagers appear as a versatile alternative to other widefield time-resolved detectors for NIR fluorescence lifetime imaging, including preclinical molecular applications.
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Affiliation(s)
- X. Michalet
- Department of Chemistry & Biochemistry, University of California at Los Angeles, Los Angeles, California, CA 90095, USA,
| | - A. Ulku
- AQUA Lab, Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - J.T. Smith
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - C. Bruschini
- AQUA Lab, Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - S. Weiss
- Department of Chemistry & Biochemistry, University of California at Los Angeles, Los Angeles, California, CA 90095, USA
| | - E. Charbon
- AQUA Lab, Ecole Polytechnique Fédérale de Lausanne (EPFL), Neuchâtel, Switzerland
| | - X. Intes
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
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20
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Jiang J, Costanzo Mata AD, Lindner S, Charbon E, Wolf M, Kalyanov A. 2.5 Hz sample rate time-domain near-infrared optical tomography based on SPAD-camera image tissue hemodynamics. Biomed Opt Express 2022; 13:133-146. [PMID: 35154859 PMCID: PMC8803024 DOI: 10.1364/boe.441061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 11/12/2021] [Accepted: 11/15/2021] [Indexed: 05/31/2023]
Abstract
Time-domain near-infrared optical tomography (TD NIROT) techniques based on diffuse light were gaining performance over the last years. They are capable of imaging tissue at several centimeters depth and reveal clinically relevant information, such as tissue oxygen saturation. In this work, we present the very first in vivo results of our SPAD camera-based TD NIROT reflectance system with a temporal resolution of ∼116 ps. It provides 2800 time of flight source-detector pairs in a compact probe of only 6 cm in diameter. Additionally, we describe a 3-step reconstruction procedure that enables accurate recovery of structural information and of the optical properties. We demonstrate the system's performance firstly in reconstructing the 3D-structure of a heterogeneous tissue phantom with tissue-like scattering and absorption properties within a volume of 9 cm diameter and 5 cm thickness. Furthermore, we performed in vivo tomography of an index finger located within a homogeneous scattering medium. We employed a fast sampling rate of 2.5 Hz to detect changes in tissue oxygenation. Tomographic reconstructions were performed in true 3D, and without prior structural information, demonstrating the powerful capabilities of the system. This shows its potential for clinical applications.
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Affiliation(s)
- Jingjing Jiang
- Biomedical Optics Research Laboratory (BORL), Dept. of Neonatology, University of Zurich / University Hospital Zurich, Switzerland
| | - Aldo Di Costanzo Mata
- Biomedical Optics Research Laboratory (BORL), Dept. of Neonatology, University of Zurich / University Hospital Zurich, Switzerland
| | - Scott Lindner
- Biomedical Optics Research Laboratory (BORL), Dept. of Neonatology, University of Zurich / University Hospital Zurich, Switzerland
- Advanced Quantum Architecture (AQUA) laboratory, School of Engineering, EPFL Lausanne, Switzerland
- now with ams OSRAM, Rüschlikon, Zurich, Switzerland
| | - Edoardo Charbon
- Advanced Quantum Architecture (AQUA) laboratory, School of Engineering, EPFL Lausanne, Switzerland
| | - Martin Wolf
- Biomedical Optics Research Laboratory (BORL), Dept. of Neonatology, University of Zurich / University Hospital Zurich, Switzerland
| | - Alexander Kalyanov
- Biomedical Optics Research Laboratory (BORL), Dept. of Neonatology, University of Zurich / University Hospital Zurich, Switzerland
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21
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Lubin G, Yaniv G, Kazes M, Ulku AC, Antolovic IM, Burri S, Bruschini C, Charbon E, Yallapragada VJ, Oron D. Resolving the Controversy in Biexciton Binding Energy of Cesium Lead Halide Perovskite Nanocrystals through Heralded Single-Particle Spectroscopy. ACS Nano 2021; 15:19581-19587. [PMID: 34846120 PMCID: PMC8717625 DOI: 10.1021/acsnano.1c06624] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Understanding exciton-exciton interaction in multiply excited nanocrystals is crucial to their utilization as functional materials. Yet, for lead halide perovskite nanocrystals, which are promising candidates for nanocrystal-based technologies, numerous contradicting values have been reported for the strength and sign of their exciton-exciton interaction. In this work, we unambiguously determine the biexciton binding energy in single cesium lead halide perovskite nanocrystals at room temperature. This is enabled by the recently introduced single-photon avalanche diode array spectrometer, capable of temporally isolating biexciton-exciton emission cascades while retaining spectral resolution. We demonstrate that CsPbBr3 nanocrystals feature an attractive exciton-exciton interaction, with a mean biexciton binding energy of 10 meV. For CsPbI3 nanocrystals, we observe a mean biexciton binding energy that is close to zero, and individual nanocrystals show either weakly attractive or weakly repulsive exciton-exciton interaction. We further show that, within ensembles of both materials, single-nanocrystal biexciton binding energies are correlated with the degree of charge-carrier confinement.
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Affiliation(s)
- Gur Lubin
- Department
of Physics of Complex Systems, Weizmann
Institute of Science, Rehovot 7610001, Israel
| | - Gili Yaniv
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Miri Kazes
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Arin Can Ulku
- School
of Engineering, École polytechnique
fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Ivan Michel Antolovic
- School
of Engineering, École polytechnique
fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Samuel Burri
- School
of Engineering, École polytechnique
fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Claudio Bruschini
- School
of Engineering, École polytechnique
fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Edoardo Charbon
- School
of Engineering, École polytechnique
fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Venkata Jayasurya Yallapragada
- Department
of Physics of Complex Systems, Weizmann
Institute of Science, Rehovot 7610001, Israel
- Department
of Physics, Indian Institute of Technology
Kanpur, Kanpur 208016, India
- (V.J.Y.)
| | - Dan Oron
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
- (D.O.)
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22
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Houwink Q, Kalisvaart D, Hung ST, Cnossen J, Fan D, Mos P, Can Ülkü A, Bruschini C, Charbon E, Smith CS. Theoretical minimum uncertainty of single-molecule localizations using a single-photon avalanche diode array. Opt Express 2021; 29:39920-39929. [PMID: 34809346 DOI: 10.1364/oe.439340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 10/12/2021] [Indexed: 06/13/2023]
Abstract
Single-photon avalanche diode (SPAD) arrays can be used for single-molecule localization microscopy (SMLM) because of their high frame rate and lack of readout noise. SPAD arrays have a binary frame output, which means photon arrivals should be described as a binomial process rather than a Poissonian process. Consequentially, the theoretical minimum uncertainty of the localizations is not accurately predicted by the Poissonian Cramér-Rao lower bound (CRLB). Here, we derive a binomial CRLB and benchmark it using simulated and experimental data. We show that if the expected photon count is larger than one for all pixels within one standard deviation of a Gaussian point spread function, the binomial CRLB gives a 46% higher theoretical uncertainty than the Poissonian CRLB. For typical SMLM photon fluxes, where no saturation occurs, the binomial CRLB predicts the same uncertainty as the Poissonian CRLB. Therefore, the binomial CRLB can be used to predict and benchmark localization uncertainty for SMLM with SPAD arrays for all practical emitter intensities.
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23
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Muntean A, Venialgo E, Ardelean A, Sachdeva A, Ripiccini E, Palubiak D, Jackson C, Charbon E. Blumino: The First Fully Integrated Analog SiPM With On-Chip Time Conversion. IEEE Trans Radiat Plasma Med Sci 2021. [DOI: 10.1109/trpms.2020.3045081] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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24
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Lubin G, Tenne R, Ulku AC, Antolovic IM, Burri S, Karg S, Yallapragada VJ, Bruschini C, Charbon E, Oron D. Heralded Spectroscopy Reveals Exciton-Exciton Correlations in Single Colloidal Quantum Dots. Nano Lett 2021; 21:6756-6763. [PMID: 34398604 PMCID: PMC8397400 DOI: 10.1021/acs.nanolett.1c01291] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Multiply excited states in semiconductor quantum dots feature intriguing physics and play a crucial role in nanocrystal-based technologies. While photoluminescence provides a natural probe to investigate these states, room-temperature single-particle spectroscopy of their emission has proved elusive due to the temporal and spectral overlap with emission from the singly excited and charged states. Here, we introduce biexciton heralded spectroscopy enabled by a single-photon avalanche diode array based spectrometer. This allows us to directly observe biexciton-exciton emission cascades and measure the biexciton binding energy of single quantum dots at room temperature, even though it is well below the scale of thermal broadening and spectral diffusion. Furthermore, we uncover correlations hitherto masked in ensembles of the biexciton binding energy with both charge-carrier confinement and fluctuations of the local electrostatic potential. Heralded spectroscopy has the potential of greatly extending our understanding of charge-carrier dynamics in multielectron systems and of parallelization of quantum optics protocols.
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Affiliation(s)
- Gur Lubin
- Deptartment
of Physics of Complex Systems, Weizmann
Institute of Science, Rehovot 7610001, Israel
| | - Ron Tenne
- Deptartment
of Physics of Complex Systems, Weizmann
Institute of Science, Rehovot 7610001, Israel
- Department
of Physics and Center for Applied Photonics, University of Konstanz, Konstanz D-78457, Germany
| | - Arin Can Ulku
- School
of Engineering, École Polytechnique
Fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Ivan Michel Antolovic
- School
of Engineering, École Polytechnique
Fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Samuel Burri
- School
of Engineering, École Polytechnique
Fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Sean Karg
- Deptartment
of Physics of Complex Systems, Weizmann
Institute of Science, Rehovot 7610001, Israel
| | | | - Claudio Bruschini
- School
of Engineering, École Polytechnique
Fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Edoardo Charbon
- School
of Engineering, École Polytechnique
Fédérale de Lausanne (EPFL), Neuchâtel 2002, Switzerland
| | - Dan Oron
- Deptartment
of Physics of Complex Systems, Weizmann
Institute of Science, Rehovot 7610001, Israel
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25
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Abstract
The growing demands on compact and high-definition single-photon avalanche diode (SPAD) arrays have motivated researchers to explore pixel miniaturization techniques to achieve sub-10 μm pixels. The scaling of the SPAD pixel size has an impact on key performance metrics, and it is, thereby, critical to conduct a systematic analysis of the underlying tradeoffs in miniaturized SPADs. On the basis of the general assumptions and constraints for layout geometry, we performed an analytical formulation of the scaling laws for the key metrics, such as the fill factor (FF), photon detection probability (PDP), dark count rate (DCR), correlated noise, and power consumption. Numerical calculations for various parameter sets indicated that some of the metrics, such as the DCR and power consumption, were improved by pixel miniaturization, whereas other metrics, such as the FF and PDP, were degraded. Comparison of the theoretically estimated scaling trends with previously published experimental results suggests that the scaling law analysis is in good agreement with practical SPAD devices. Our scaling law analysis could provide a useful tool to conduct a detailed performance comparison between various process, device, and layout configurations, which is essential for pushing the limit of SPAD pixel miniaturization toward sub-2 μm-pitch SPADs.
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Affiliation(s)
- Kazuhiro Morimoto
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2000 Neuchâtel, Switzerland
- Canon Inc., Kanagawa 212-8602, Japan;
| | - Edoardo Charbon
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2000 Neuchâtel, Switzerland
- Correspondence:
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26
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Ngo NH, Shimonomura K, Ando T, Shimura T, Watanabe H, Takehara K, Nguyen AQ, Charbon E, Etoh TG. A Pixel Design of a Branching Ultra-Highspeed Image Sensor. Sensors (Basel) 2021; 21:s21072506. [PMID: 33916733 PMCID: PMC8038384 DOI: 10.3390/s21072506] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 03/18/2021] [Accepted: 03/29/2021] [Indexed: 11/16/2022]
Abstract
A burst image sensor named Hanabi, meaning fireworks in Japanese, includes a branching CCD and multiple CMOS readout circuits. The sensor is backside-illuminated with a light/charge guide pipe to minimize the temporal resolution by suppressing the horizontal motion of signal carriers. On the front side, the pixel has a guide gate at the center, branching to six first-branching gates, each bifurcating to second-branching gates, and finally connected to 12 (=6×2) floating diffusions. The signals are either read out after an image capture operation to replay 12 to 48 consecutive images, or continuously transferred to a memory chip stacked on the front side of the sensor chip and converted to digital signals. A CCD burst image sensor enables a noiseless signal transfer from a photodiode to the in-situ storage even at very high frame rates. However, the pixel count conflicts with the frame count due to the large pixel size for the relatively large in-pixel CCD memory elements. A CMOS burst image sensor can use small trench-type capacitors for memory elements, instead of CCD channels. However, the transfer noise from a floating diffusion to the memory element increases in proportion to the square root of the frame rate. The Hanabi chip overcomes the compromise between these pros and cons.
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Affiliation(s)
- Nguyen Hoai Ngo
- College of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan; (K.S.); (T.A.)
- Correspondence: (N.H.N.); (T.G.E.)
| | - Kazuhiro Shimonomura
- College of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan; (K.S.); (T.A.)
| | - Taeko Ando
- College of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan; (K.S.); (T.A.)
| | - Takayoshi Shimura
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; (T.S.); (H.W.)
| | - Heiji Watanabe
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; (T.S.); (H.W.)
| | - Kohsei Takehara
- School of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan;
| | - Anh Quang Nguyen
- School of Electronics and Telecommunications, Hanoi University of Science and Technology, 1 Dai Co Viet, Bach Khoa, Hai Ba Trung, Hanoi 100803, Vietnam;
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, EPFL, Rue de la Maladière 71b, Case Postale 526, CH-2002 Neuchâtel, Switzerland;
| | - Takeharu Goji Etoh
- College of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan; (K.S.); (T.A.)
- Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; (T.S.); (H.W.)
- Correspondence: (N.H.N.); (T.G.E.)
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27
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Zickus V, Wu ML, Morimoto K, Kapitany V, Fatima A, Turpin A, Insall R, Whitelaw J, Machesky L, Bruschini C, Faccio D, Charbon E. Fluorescence lifetime imaging with a megapixel SPAD camera and neural network lifetime estimation. Sci Rep 2020; 10:20986. [PMID: 33268900 PMCID: PMC7710711 DOI: 10.1038/s41598-020-77737-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 11/06/2020] [Indexed: 01/07/2023] Open
Abstract
Fluorescence lifetime imaging microscopy (FLIM) is a key technology that provides direct insight into cell metabolism, cell dynamics and protein activity. However, determining the lifetimes of different fluorescent proteins requires the detection of a relatively large number of photons, hence slowing down total acquisition times. Moreover, there are many cases, for example in studies of cell collectives, where wide-field imaging is desired. We report scan-less wide-field FLIM based on a 0.5 MP resolution, time-gated Single Photon Avalanche Diode (SPAD) camera, with acquisition rates up to 1 Hz. Fluorescence lifetime estimation is performed via a pre-trained artificial neural network with 1000-fold improvement in processing times compared to standard least squares fitting techniques. We utilised our system to image HT1080-human fibrosarcoma cell line as well as Convallaria. The results show promise for real-time FLIM and a viable route towards multi-megapixel fluorescence lifetime images, with a proof-of-principle mosaic image shown with 3.6 MP.
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Affiliation(s)
- Vytautas Zickus
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Ming-Lo Wu
- Advanced Quantum Architecture Laboratory, Ecole Polytechnique Fédérale de Lausanne, 2002, Neuchâtel, Switzerland
| | - Kazuhiro Morimoto
- Advanced Quantum Architecture Laboratory, Ecole Polytechnique Fédérale de Lausanne, 2002, Neuchâtel, Switzerland
| | - Valentin Kapitany
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Areeba Fatima
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Alex Turpin
- School of Computing Science, University of Glasgow, Glasgow, G12 8LT, UK
| | - Robert Insall
- University of Glasgow Institute of Cancer Sciences, Glasgow, UK.,Cancer Research UK, Beatson Institute, Glasgow, UK
| | - Jamie Whitelaw
- University of Glasgow Institute of Cancer Sciences, Glasgow, UK.,Cancer Research UK, Beatson Institute, Glasgow, UK
| | - Laura Machesky
- University of Glasgow Institute of Cancer Sciences, Glasgow, UK.,Cancer Research UK, Beatson Institute, Glasgow, UK
| | - Claudio Bruschini
- Advanced Quantum Architecture Laboratory, Ecole Polytechnique Fédérale de Lausanne, 2002, Neuchâtel, Switzerland
| | - Daniele Faccio
- School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK.
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, Ecole Polytechnique Fédérale de Lausanne, 2002, Neuchâtel, Switzerland.
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28
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Lecoq P, Morel C, Prior JO, Visvikis D, Gundacker S, Auffray E, Križan P, Turtos RM, Thers D, Charbon E, Varela J, de La Taille C, Rivetti A, Breton D, Pratte JF, Nuyts J, Surti S, Vandenberghe S, Marsden P, Parodi K, Benlloch JM, Benoit M. Roadmap toward the 10 ps time-of-flight PET challenge. Phys Med Biol 2020; 65:21RM01. [PMID: 32434156 PMCID: PMC7721485 DOI: 10.1088/1361-6560/ab9500] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Since the seventies, positron emission tomography (PET) has become an invaluable medical molecular imaging modality with an unprecedented sensitivity at the picomolar level, especially for cancer diagnosis and the monitoring of its response to therapy. More recently, its combination with x-ray computed tomography (CT) or magnetic resonance (MR) has added high precision anatomic information in fused PET/CT and PET/MR images, thus compensating for the modest intrinsic spatial resolution of PET. Nevertheless, a number of medical challenges call for further improvements in PET sensitivity. These concern in particular new treatment opportunities in the context personalized (also called precision) medicine, such as the need to dynamically track a small number of cells in cancer immunotherapy or stem cells for tissue repair procedures. A better signal-to-noise ratio (SNR) in the image would allow detecting smaller size tumours together with a better staging of the patients, thus increasing the chances of putting cancer in complete remission. Moreover, there is an increasing demand for reducing the radioactive doses injected to the patients without impairing image quality. There are three ways to improve PET scanner sensitivity: improving detector efficiency, increasing geometrical acceptance of the imaging device and pushing the timing performance of the detectors. Currently, some pre-localization of the electron-positron annihilation along a line-of-response (LOR) given by the detection of a pair of annihilation photons is provided by the detection of the time difference between the two photons, also known as the time-of-flight (TOF) difference of the photons, whose accuracy is given by the coincidence time resolution (CTR). A CTR of about 10 picoseconds FWHM will ultimately allow to obtain a direct 3D volume representation of the activity distribution of a positron emitting radiopharmaceutical, at the millimetre level, thus introducing a quantum leap in PET imaging and quantification and fostering more frequent use of 11C radiopharmaceuticals. The present roadmap article toward the advent of 10 ps TOF-PET addresses the status and current/future challenges along the development of TOF-PET with the objective to reach this mythic 10 ps frontier that will open the door to real-time volume imaging virtually without tomographic inversion. The medical impact and prospects to achieve this technological revolution from the detection and image reconstruction point-of-views, together with a few perspectives beyond the TOF-PET application are discussed.
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Affiliation(s)
- Paul Lecoq
- CERN, department EP, Geneva, Switzerland
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29
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Jiang J, Costanzo Mata AD, Lindner S, Charbon E, Wolf M, Kalyanov A. Dynamic time domain near-infrared optical tomography based on a SPAD camera. Biomed Opt Express 2020; 11:5470-5477. [PMID: 33149964 PMCID: PMC7587269 DOI: 10.1364/boe.399387] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/17/2020] [Accepted: 08/26/2020] [Indexed: 05/03/2023]
Abstract
In many clinical applications it is relevant to observe dynamic changes in oxygenation. Therefore the ability of dynamic imaging with time domain (TD) near-infrared optical tomography (NIROT) will be important. But fast imaging is a challenge. The data acquisition of our handheld TD NIROT system based on single photon avalanche diode (SPAD) camera and 11 light sources was consequently accelerated. We tested the system on a diffusive medium simulating tissue with a moving object embedded. With 3D image reconstruction, the moving object was correctly located using only 0.2 s exposure time per source.
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Affiliation(s)
- Jingjing Jiang
- Biomedical Optics Research Laboratory, University Hospital Zurich and University of Zurich, Switzerland
| | - Aldo Di Costanzo Mata
- Biomedical Optics Research Laboratory, University Hospital Zurich and University of Zurich, Switzerland
| | - Scott Lindner
- Biomedical Optics Research Laboratory, University Hospital Zurich and University of Zurich, Switzerland
- Advanced Quantum Architecture Laboratory, EPFL, 2002 Neuchâtel, Switzerland
- Now with ams AG, Ruschlikon, Switzerland
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, EPFL, 2002 Neuchâtel, Switzerland
| | - Martin Wolf
- Biomedical Optics Research Laboratory, University Hospital Zurich and University of Zurich, Switzerland
| | - Alexander Kalyanov
- Biomedical Optics Research Laboratory, University Hospital Zurich and University of Zurich, Switzerland
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30
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Jiang J, Costanzo Mata AD, Lindner S, Zhang C, Charbon E, Wolf M, Kalyanov A. Image reconstruction for novel time domain near infrared optical tomography: towards clinical applications. Biomed Opt Express 2020; 11:4723-4734. [PMID: 32923074 PMCID: PMC7449738 DOI: 10.1364/boe.398885] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/17/2020] [Accepted: 07/17/2020] [Indexed: 05/04/2023]
Abstract
Near infrared optical tomography (NIROT) is an emerging modality that enables imaging the oxygenation of tissue, which is a biomarker of tremendous clinical relevance. Measuring in reflectance is usually required when NIROT is applied in clinical scenarios. Single photon avalanche diode (SPAD) array technology provides a compact solution for time domain (TD) NIROT to gain huge temporal and spatial information. This makes it possible to image complex structures in tissue. The main aim of this paper is to validate the wavelength normalization method for our new TD NIROT experimentally by exposing it to a particularly difficult challenge: the recovery of two inclusions at different depths. The proposed reconstruction algorithm aims to tackle systematic errors and other artifacts with known wavelength-dependent relation. We validated the device and reconstruction method experimentally on a silicone phantom with two inclusions: one at depth of 10 mm and the other at 15 mm. Despite this tough challenge for reflectance NIROT, the system was able to localize both inclusions accurately.
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Affiliation(s)
- Jingjing Jiang
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
| | - Aldo Di Costanzo Mata
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
| | - Scott Lindner
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
- Advanced Quantum Architecture Laboratory, EPFL, 2002 Neuchâtel, Switzerland
| | - Chao Zhang
- Advanced Quantum Architecture Laboratory, EPFL, 2002 Neuchâtel, Switzerland
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, EPFL, 2002 Neuchâtel, Switzerland
| | - Martin Wolf
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
| | - Alexander Kalyanov
- Biomedical Optics Research Laboratory, Dept. of Neonatology, University Hospital Zurich and University of Zurich, Switzerland
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31
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Morimoto K, Charbon E. High fill-factor miniaturized SPAD arrays with a guard-ring-sharing technique. Opt Express 2020; 28:13068-13080. [PMID: 32403788 DOI: 10.1364/oe.389216] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 03/30/2020] [Indexed: 06/11/2023]
Abstract
We present a novel guard-ring-sharing technique to push the limit of SPAD pixel miniaturization, and to demonstrate the operation of SPAD arrays with a 2.2 µm-pitch, the smallest ever reported. Device simulation and preliminary tests suggest that the optimized device design ensures the electrical isolation of SPADs with guard-ring sharing. 4×4 SPAD arrays with two parallel selective readout circuits are designed in 180 nm CMOS technology. SPAD characteristics for the pixel pitch of 2.2, 3, and 4 µm are systematically measured as a function of an active diameter, active-to-active distance, and excess bias. For a 4 µm-pitch, the fill factor is 42.4%, the maximum PDP 33.5%, the median DCR 2.5 cps, the timing jitter 88 ps, and the crosstalk probability is 3.57%, while the afterpulsing probability is 0.21%. Finally, we verified the feasibility of the proposed technique towards compact multi-megapixel 3D-stacked SPAD arrays.
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32
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Ren W, Jiang J, Costanzo Mata AD, Kalyanov A, Ripoll J, Lindner S, Charbon E, Zhang C, Rudin M, Wolf M. Multimodal imaging combining time-domain near-infrared optical tomography and continuous-wave fluorescence molecular tomography. Opt Express 2020; 28:9860-9874. [PMID: 32225585 DOI: 10.1364/oe.385392] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/02/2020] [Indexed: 06/10/2023]
Abstract
Fluorescence molecular tomography (FMT) emerges as a powerful non-invasive imaging tool with the ability to resolve fluorescence signals from sources located deep in living tissues. Yet, the accuracy of FMT reconstruction depends on the deviation of the assumed optical properties from the actual values. In this work, we improved the accuracy of the initial optical properties required for FMT using a new-generation time-domain (TD) near-infrared optical tomography (NIROT) system, which effectively decouples scattering and absorption coefficients. We proposed a multimodal paradigm combining TD-NIROT and continuous-wave (CW) FMT. Both numerical simulation and experiments were performed on a heterogeneous phantom containing a fluorescent inclusion. The results demonstrate significant improvement in the FMT reconstruction by taking the NIROT-derived optical properties as prior information. The multimodal method is attractive for preclinical studies and tumor diagnostics since both functional and molecular information can be obtained.
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33
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Ulku A, Ardelean A, Antolovic M, Weiss S, Charbon E, Bruschini C, Michalet X. Wide-field time-gated SPAD imager for phasor-based FLIM applications. Methods Appl Fluoresc 2020; 8:024002. [PMID: 31968310 PMCID: PMC8827132 DOI: 10.1088/2050-6120/ab6ed7] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We describe the performance of a new wide area time-gated single-photon
avalanche diode (SPAD) array for phasor-FLIM, exploring the effect of gate
length, gate number and signal intensity on the measured lifetime accuracy and
precision. We conclude that the detector functions essentially as an ideal shot
noise limited sensor and is capable of video rate FLIM measurement. The phasor
approach used in this work appears ideally suited to handle the large amount of
data generated by this type of very large sensor (512 × 512 pixels), even
in the case of small number of gates and limited photon budget.
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34
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Bruschini C, Homulle H, Antolovic IM, Burri S, Charbon E. Erratum: Author Correction: Single-photon avalanche diode imagers in biophotonics: review and outlook. Light Sci Appl 2020; 9:12. [PMID: 32025295 PMCID: PMC6987173 DOI: 10.1038/s41377-020-0248-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
[This corrects the article DOI: 10.1038/s41377-019-0191-5.].
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35
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Ankri R, Basu A, Ulku AC, Bruschini C, Charbon E, Weiss S, Michalet X. Single-Photon, Time-Gated, Phasor-Based Fluorescence Lifetime Imaging through Highly Scattering Medium. ACS Photonics 2020; 7:68-79. [PMID: 35936550 PMCID: PMC9355389 DOI: 10.1021/acsphotonics.9b00874] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Fluorescence lifetime imaging (FLI) is increasingly recognized as a powerful tool for biochemical and cellular investigations, including in vivo applications. Fluorescence lifetime is an intrinsic characteristic of any fluorescent dye which, to a large extent, does not depend on excitation intensity and signal level. In particular, it allows distinguishing dyes with similar emission spectra, offering additional multiplexing capabilities. However, in vivo FLI in the visible range is complicated by the contamination by (i) tissue autofluorescence, which decreases contrast, and by (ii) light scattering and absorption in tissues, which significantly reduce fluorescence intensity and modify the temporal profile of the signal. Here, we demonstrate how these issues can be accounted for and overcome, using a new time-gated single-photon avalanche diode array camera, SwissSPAD2, combined with phasor analysis to provide a simple and fast visual method for lifetime imaging. In particular, we show how phasor dispersion increases with increasing scattering and/or decreasing fluorescence intensity. Next, we show that as long as the fluorescence signal of interest is larger than the phantom autofluorescence, the presence of a distinct lifetime can be clearly identified with appropriate background correction. We use these results to demonstrate the detection of A459 cells expressing the fluorescent protein mCyRFP1 through highly scattering and autofluorescent phantom layers. These results showcase the possibility to perform FLI in challenging conditions, using standard, bright, visible fluorophore or fluorescence proteins.
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Affiliation(s)
- Rinat Ankri
- Department of Chemistry & Biochemistry, UCLA, Los Angeles, California 90095, United States
- Corresponding Authors:.
| | - Arkaprabha Basu
- Department of Chemistry & Biochemistry, UCLA, Los Angeles, California 90095, United States
| | - Arin Can Ulku
- School of Engineering, École Polytechnique Fédérale de Lausanne, Neuchâtel 1015, Switzerland
| | - Claudio Bruschini
- School of Engineering, École Polytechnique Fédérale de Lausanne, Neuchâtel 1015, Switzerland
| | - Edoardo Charbon
- School of Engineering, École Polytechnique Fédérale de Lausanne, Neuchâtel 1015, Switzerland
| | - Shimon Weiss
- Department of Chemistry & Biochemistry, UCLA, Los Angeles, California 90095, United States
| | - Xavier Michalet
- Department of Chemistry & Biochemistry, UCLA, Los Angeles, California 90095, United States
- Corresponding Authors:.
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36
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Padmanabhan P, Zhang C, Charbon E. Modeling and Analysis of a Direct Time-of-Flight Sensor Architecture for LiDAR Applications. Sensors (Basel) 2019; 19:s19245464. [PMID: 31835807 PMCID: PMC6960641 DOI: 10.3390/s19245464] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/29/2019] [Accepted: 12/05/2019] [Indexed: 11/29/2022]
Abstract
Direct time-of-flight (DTOF) is a prominent depth sensing method in light detection and ranging (LiDAR) applications. Single-photon avalanche diode (SPAD) arrays integrated in DTOF sensors have demonstrated excellent ranging and 3D imaging capabilities, making them promising candidates for LiDARs. However, high background noise due to solar exposure limits their performance and degrades the signal-to-background noise ratio (SBR). Noise-filtering techniques based on coincidence detection and time-gating have been implemented to mitigate this challenge but 3D imaging of a wide dynamic range scene is an ongoing issue. In this paper, we propose a coincidence-based DTOF sensor architecture to address the aforementioned challenges. The architecture is analyzed using a probabilistic model and simulation. A flash LiDAR setup is simulated with typical operating conditions of a wide angle field-of-view (FOV = 40°) in a 50 klux ambient light assumption. Single-point ranging simulations are obtained for distances up to 150 m using the DTOF model. An activity-dependent coincidence is proposed as a way to improve imaging of wide dynamic range targets. An example scene with targets ranging between 8–60% reflectivity is used to simulate the proposed method. The model predicts that a single threshold cannot yield an accurate reconstruction and a higher (lower) reflective target requires a higher (lower) coincidence threshold. Further, a pixel-clustering scheme is introduced, capable of providing multiple simultaneous timing information as a means to enhance throughput and reduce timing uncertainty. Example scenes are reconstructed to distinguish up to 4 distinct target peaks simulated with a resolution of 500 ps. Alternatively, a time-gating mode is simulated where in the DTOF sensor performs target-selective ranging. Simulation results show reconstruction of a 10% reflective target at 20 m in the presence of a retro-reflective equivalent with a 60% reflectivity at 5 m within the same FOV.
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Affiliation(s)
- Preethi Padmanabhan
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2000 Neuchâtel, Switzerland;
- Correspondence: ; Tel.: +41-216-954-413
| | - Chao Zhang
- AQUA Laboratory, Delft University of Technology (TU Delft), 2628 CD Delft, The Netherlands;
| | - Edoardo Charbon
- AQUA Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), 2000 Neuchâtel, Switzerland;
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Lubin G, Tenne R, Michel Antolovic I, Charbon E, Bruschini C, Oron D. Quantum correlation measurement with single photon avalanche diode arrays. Opt Express 2019; 27:32863-32882. [PMID: 31878363 DOI: 10.1364/oe.27.032863] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 10/03/2019] [Indexed: 05/20/2023]
Abstract
Temporal photon correlation measurement, instrumental to probing the quantum properties of light, typically requires multiple single photon detectors. Progress in single photon avalanche diode (SPAD) array technology highlights their potential as high-performance detector arrays for quantum imaging and photon number-resolving (PNR) experiments. Here, we demonstrate this potential by incorporating a novel on-chip SPAD array with 42% peak photon detection efficiency, low dark count rate and crosstalk probability of 0.14% per detection in a confocal microscope. This enables reliable measurements of second and third order photon correlations from a single quantum dot emitter. Our analysis overcomes the inter-detector optical crosstalk background even though it is over an order of magnitude larger than our faint signal. To showcase the vast application space of such an approach, we implement a recently introduced super-resolution imaging method, quantum image scanning microscopy (Q-ISM).
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Bruschini C, Homulle H, Antolovic IM, Burri S, Charbon E. Single-photon avalanche diode imagers in biophotonics: review and outlook. Light Sci Appl 2019; 8:87. [PMID: 31645931 PMCID: PMC6804596 DOI: 10.1038/s41377-019-0191-5] [Citation(s) in RCA: 118] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 07/30/2019] [Accepted: 08/07/2019] [Indexed: 05/08/2023]
Abstract
Single-photon avalanche diode (SPAD) arrays are solid-state detectors that offer imaging capabilities at the level of individual photons, with unparalleled photon counting and time-resolved performance. This fascinating technology has progressed at a very fast pace in the past 15 years, since its inception in standard CMOS technology in 2003. A host of architectures have been investigated, ranging from simpler implementations, based solely on off-chip data processing, to progressively "smarter" sensors including on-chip, or even pixel level, time-stamping and processing capabilities. As the technology has matured, a range of biophotonics applications have been explored, including (endoscopic) FLIM, (multibeam multiphoton) FLIM-FRET, SPIM-FCS, super-resolution microscopy, time-resolved Raman spectroscopy, NIROT and PET. We will review some representative sensors and their corresponding applications, including the most relevant challenges faced by chip designers and end-users. Finally, we will provide an outlook on the future of this fascinating technology.
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Venialgo E, Lusardi N, Garzetti F, Geraci A, Brunner SE, Schaart DR, Charbon E. Toward a Full-Flexible and Fast-Prototyping TOF-PET Block Detector Based on TDC-on-FPGA. IEEE Trans Radiat Plasma Med Sci 2019. [DOI: 10.1109/trpms.2018.2874358] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Etoh TG, Okinaka T, Takano Y, Takehara K, Nakano H, Shimonomura K, Ando T, Ngo N, Kamakura Y, Dao VTS, Nguyen AQ, Charbon E, Zhang C, De Moor P, Goetschalckx P, Haspeslagh L. Light-In-Flight Imaging by a Silicon Image Sensor: Toward the Theoretical Highest Frame Rate. Sensors (Basel) 2019; 19:s19102247. [PMID: 31096653 PMCID: PMC6567881 DOI: 10.3390/s19102247] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/06/2019] [Accepted: 05/10/2019] [Indexed: 11/25/2022]
Abstract
Light in flight was captured by a single shot of a newly developed backside-illuminated multi-collection-gate image sensor at a frame interval of 10 ns without high-speed gating devices such as a streak camera or post data processes. This paper reports the achievement and further evolution of the image sensor toward the theoretical temporal resolution limit of 11.1 ps derived by the authors. The theoretical analysis revealed the conditions to minimize the temporal resolution. Simulations show that the image sensor designed following the specified conditions and fabricated by existing technology will achieve a frame interval of 50 ps. The sensor, 200 times faster than our latest sensor will innovate advanced analytical apparatuses using time-of-flight or lifetime measurements, such as imaging TOF-MS, FLIM, pulse neutron tomography, PET, LIDAR, and more, beyond these known applications.
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Affiliation(s)
- Takeharu Goji Etoh
- School of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higahsi-Osaka, Osaka 577-8502, Japan.
- School of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan.
| | - Tomoo Okinaka
- School of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higahsi-Osaka, Osaka 577-8502, Japan.
| | - Yasuhide Takano
- School of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higahsi-Osaka, Osaka 577-8502, Japan.
| | - Kohsei Takehara
- School of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higahsi-Osaka, Osaka 577-8502, Japan.
| | - Hitoshi Nakano
- School of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higahsi-Osaka, Osaka 577-8502, Japan.
| | - Kazuhiro Shimonomura
- School of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan.
| | - Taeko Ando
- School of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan.
| | - Nguyen Ngo
- School of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan.
| | - Yoshinari Kamakura
- School of Engineering, Osaka University, 1-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
| | - Vu Truon Son Dao
- Department of Industrial and Systems Engineering, International University, Vietnam National University HCMC, Khu Pho 6, Thu Duc, Ho Chi Minh City 700000, Vietnam.
| | - Anh Quang Nguyen
- School of Electronics and Telecommunications, Hanoi University of Science and technology, 1 Dai Co Viet, Bach Khoa, Hai Ba Trung, Hanoi 100803, Vietnam.
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, EPFL, Rue de la Maladiere 71b, CH-2002 Neuchatel 2, Switzerland.
| | - Chao Zhang
- Faculty of Engineering, Mathematics and Computer Science, Delft University of Technology, Mekelweg 4, Delft, 2628 CD, The Netherlands.
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Ulku AC, Bruschini C, Antolovic IM, Weiss S, Michalet X, Charbon E. Phasor-based widefield FLIM using a gated 512×512 single-photon SPAD imager. Proc SPIE Int Soc Opt Eng 2019; 10882. [PMID: 33859449 DOI: 10.1117/12.2511148] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Single-photon avalanche diode (SPAD) imagers can perform fast time-resolved imaging in a compact form factor, by exploiting the processing capability and speed of integrated CMOS electronics. Developments in SPAD imagers have recently made them compatible with widefield microscopy, thanks to array formats approaching one megapixel and sensitivity and noise levels approaching those of established technologies. In this paper, phasor-based FLIM is demonstrated with a gated binary 512×512 SPAD imager, which can operate with a gate length as short as 5.75 ns, a minimum gate step of 17.9 ps, and up to 98 kfps readout rate (1-bit frames). Lifetimes of ATTO 550 and Rhodamine 6G (R6G) solutions were measured across a 472×256 sub-array using phasor analysis, acquiring data by shifting a 13.1 ns gate window across the 50 ns laser period. The measurement accuracy obtained when employing such a scheme based on long, overlapping gates was validated by comparison with TCSPC measurements and fitting analysis results based on a standard Levenberg-Marquardt algorithm (>90% accuracy for the lifetime of R6G and ATTO 550). This demonstrates the ability of the proposed method to measure short lifetimes without minimum gate length requirements. The FLIM frame rate of the overall system can be increased up to a few fps for phasor-based widefield FLIM (moving closer to real-time operation) by FPGA-based parallel computation with continuous acquisition at the full speed of 98 kfps.
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Affiliation(s)
| | | | | | - Shimon Weiss
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA USA
| | - Xavier Michalet
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA USA
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Ardelean A, Ulku AC, Michalet X, Charbon E, Bruschini C. Fluorescence lifetime imaging with a single-photon SPAD array using long overlapping gates: an experimental and theoretical study. Proc SPIE Int Soc Opt Eng 2019; 10882:108820Y. [PMID: 33833477 PMCID: PMC8026147 DOI: 10.1117/12.2511287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Developing large arrays of single-photon avalanche diodes (SPADs) with on-chip time-correlated single-photon counting (TCSPC) capabilities continues to be a difficult task due to stringent silicon real estate constraints, high data rates and system complexity. As an alternative to TCSPC, time-gated architectures have been proposed, where the numbers of photons detected within different time gates are used as a replacement to the usual time-resolved luminescence decay. However, because of technological limitations, the minimum gate length implement is on the order of nanoseconds, longer than most fluorophore lifetimes of interest. However, recent FLIM measurements have shown that it is mainly the gate step and rise/fall time, rather than its length, which determine lifetime resolution. In addition, the large number of photons captured by longer gates results in higher SNR. In this paper, we study the effects of using long, overlapping gates on lifetime extraction by phasor analysis, using a recently developed 512×512 time-gated SPAD array. The experiments used Cy3B, Rhodamine 6G and Atto550 dyes as test samples. The gate window length was varied between 11.3 ns and 23 ns while the gate step was varied between 17.86 ps and 3 ns. We validated the results with a standard TCSPC setup and investigated the case of multi-exponential samples through simulations. Results indicate that lifetime extraction is not degraded by the use of longer gates, nor is the ability to resolve multi-exponential decays.
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Affiliation(s)
- Andrei Ardelean
- AQUA Laboratory, EPFL, 71b Rue de la Maladière, Neuchâtel, Switzerland
| | - Arin Can Ulku
- AQUA Laboratory, EPFL, 71b Rue de la Maladière, Neuchâtel, Switzerland
| | - Xavier Michalet
- Department of Chemistry and Biochemistry, UCLA, 607 Charles E. Young Drive East, Los Angeles, USA
| | - Edoardo Charbon
- AQUA Laboratory, EPFL, 71b Rue de la Maladière, Neuchâtel, Switzerland
| | - Claudio Bruschini
- AQUA Laboratory, EPFL, 71b Rue de la Maladière, Neuchâtel, Switzerland
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Ulku AC, Bruschini C, Antolovic IM, Charbon E, Kuo Y, Ankri R, Weiss S, Michalet X. A 512×512 SPAD Image Sensor with Integrated Gating for Widefield FLIM. IEEE J Sel Top Quantum Electron 2019; 25:6801212. [PMID: 31156324 PMCID: PMC6541425 DOI: 10.1109/jstqe.2018.2867439] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We report on SwissSPAD2, an image sensor with 512×512 photon-counting pixels, each comprising a single-photon avalanche diode (SPAD), a 1-bit memory, and a gating mechanism capable of turning the SPAD on and off, with a skew of 250ps and 344ps, respectively, for a minimum duration of 5.75ns. The sensor is designed to achieve a frame rate of up to 97,700 binary frames per second and sub-40ps gate shifts. By synchronizing it with a pulsed laser and using multiple successive overlapping gates, one can reconstruct a molecule's fluorescent response with picosecond temporal resolution. Thanks to the sensor's number of pixels (the largest to date) and the fully integrated gated operation, SwissSPAD2 enables widefield FLIM with an all-solid-state solution and at relatively high frame rates. This was demonstrated with preliminary results on organic dyes and semiconductor quantum dots using both decay fitting and phasor analysis. Furthermore, pixels with an exceptionally low dark count rate and high photon detection probability enable uniform and high quality imaging of biologically relevant fluorescent samples stained with multiple dyes. While future versions will feature the addition of microlenses and optimize firmware speed, our results open the way to low-cost alternatives to commercially available scientific time-resolved imagers.
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Affiliation(s)
- Arin C Ulku
- School of Engineering, École Polytechnique Fédérale de Lausanne, Neuchâtel, 2002, Switzerland
| | - Claudio Bruschini
- School of Engineering, École Polytechnique Fédérale de Lausanne, Neuchâtel, 2002, Switzerland
| | - Ivan Michel Antolovic
- School of Engineering, École Polytechnique Fédérale de Lausanne, Neuchâtel, 2002, Switzerland
| | - Edoardo Charbon
- School of Engineering, École Polytechnique Fédérale de Lausanne, Neuchâtel, 2002, Switzerland
| | - Yung Kuo
- Department of Chemistry and Biochemistry, University of California at Los Angeles (UCLA), Los Angeles, CA, 90095-1569
| | - Rinat Ankri
- Department of Chemistry and Biochemistry, University of California at Los Angeles (UCLA), Los Angeles, CA, 90095-1569
| | - Shimon Weiss
- Department of Chemistry and Biochemistry, University of California at Los Angeles (UCLA), Los Angeles, CA, 90095-1569
| | - Xavier Michalet
- Department of Chemistry and Biochemistry, University of California at Los Angeles (UCLA), Los Angeles, CA, 90095-1569
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Zhang C, Lindner S, Antolovic IM, Wolf M, Charbon E. A CMOS SPAD Imager with Collision Detection and 128 Dynamically Reallocating TDCs for Single-Photon Counting and 3D Time-of-Flight Imaging. Sensors (Basel) 2018; 18:s18114016. [PMID: 30453648 PMCID: PMC6263909 DOI: 10.3390/s18114016] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 11/14/2018] [Accepted: 11/15/2018] [Indexed: 11/16/2022]
Abstract
Per-pixel time-to-digital converter (TDC) architectures have been exploited by single-photon avalanche diode (SPAD) sensors to achieve high photon throughput, but at the expense of fill factor, pixel pitch and readout efficiency. In contrast, TDC sharing architecture usually features high fill factor at small pixel pitch and energy efficient event-driven readout. While the photon throughput is not necessarily lower than that of per-pixel TDC architectures, since the throughput is not only decided by the TDC number but also the readout bandwidth. In this paper, a SPAD sensor with 32 × 32 pixels fabricated with a 180 nm CMOS image sensor technology is presented, where dynamically reallocating TDCs were implemented to achieve the same photon throughput as that of per-pixel TDCs. Each 4 TDCs are shared by 32 pixels via a collision detection bus, which enables a fill factor of 28% with a pixel pitch of 28.5 μm. The TDCs were characterized, obtaining the peak-to-peak differential and integral non-linearity of -0.07/+0.08 LSB and -0.38/+0.75 LSB, respectively. The sensor was demonstrated in a scanning light-detection-and-ranging (LiDAR) system equipped with an ultra-low power laser, achieving depth imaging up to 10 m at 6 frames/s with a resolution of 64 × 64 with 50 lux background light.
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Affiliation(s)
- Chao Zhang
- Quantum and Computer Engineering, Delft University of Technology, Mekelweg 4, 2628CD Delft, The Netherlands.
| | - Scott Lindner
- Biomedical Optics Research Laboratory, University of Zurich, Rämistrasse 71, 8006 Zürich, Switzerland.
- Advanced Quantum Architecture Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Route Cantonale, 1015 Lausanne, Switzerland.
| | - Ivan Michel Antolovic
- Advanced Quantum Architecture Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Route Cantonale, 1015 Lausanne, Switzerland.
| | - Martin Wolf
- Biomedical Optics Research Laboratory, University of Zurich, Rämistrasse 71, 8006 Zürich, Switzerland.
| | - Edoardo Charbon
- Advanced Quantum Architecture Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Route Cantonale, 1015 Lausanne, Switzerland.
- Kavli Institute of Nanoscience, 2628CJ Delft, The Netherlands.
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Bruschini C, Veerappan C, Gramuglia F, Bijwaard M, Papp Z, Charbon E. A Sensor Network Architecture for Digital SiPM-Based PET Systems. IEEE Trans Radiat Plasma Med Sci 2018. [DOI: 10.1109/trpms.2018.2866953] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Antolovic IM, Bruschini C, Charbon E. Dynamic range extension for photon counting arrays. Opt Express 2018; 26:22234-22248. [PMID: 30130919 DOI: 10.1364/oe.26.022234] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 06/27/2018] [Indexed: 05/20/2023]
Abstract
Confocal microscopes use photomultiplier tubes and hybrid detectors due to their large dynamic range, which typically exceeds the one of single-photon avalanche diodes (SPADs). The latter, due to their photon counting operation, are usually limited to an output count rate to 1/Tdead. In this paper, we present a thorough analysis, which can actually be applied to any photon counting detector, on how to extend the SPAD dynamic range by exploiting the nonlinear photon response at high count rates and for different recharge mechanisms. We applied passive, active event-driven and clock-driven (i.e. clocked, following quanta image sensor response) recharge directly to the SPADs. The photon response, photon count standard deviation, signal-to-noise ratio and dynamic range were measured and compared to models. Measurements were performed with a CMOS SPAD array targeted for image scanning microscopy, featuring best-in-class 11 V excess bias, 55% peak photon detection probability at 520 nm and >40% from 440 to 640 nm. The array features an extremely low median dark count rate below 0.05 cps/μm2 at 9 V of excess bias and 0°C. We show that active event-driven recharge provides ×75 dynamic range extension and offers novel ways for high dynamic range imaging. When compared to the clock-driven recharge and the quanta image sensor approach, the dynamic range is extended by a factor of ×12.7-26.4. Additionally, for the first time, we evaluate the influence of clock-driven recharge on the SPAD afterpulsing.
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Buchholz J, Krieger J, Bruschini C, Burri S, Ardelean A, Charbon E, Langowski J. Widefield High Frame Rate Single-Photon SPAD Imagers for SPIM-FCS. Biophys J 2018; 114:2455-2464. [PMID: 29753448 DOI: 10.1016/j.bpj.2018.04.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 04/06/2018] [Accepted: 04/13/2018] [Indexed: 11/24/2022] Open
Abstract
Photon-counting sensors based on standard complementary metal-oxide-semiconductor single-photon avalanche diodes (SPADs) represent an emerging class of imagers that enable the counting and/or timing of single photons at zero readout noise (better than high-speed electron-multiplying charge-coupling devices) and over large arrays. They have seen substantial progress over the last 15 years, increasing their spatial resolution, timing accuracy, and sensitivity while reducing spurious signals such as afterpulsing and dark counts. They are increasingly being applied for time-resolved applications with the added advantage of enabling real-time options such as autocorrelation. We report in this study on the use of such a state-of-the-art 512 × 128 SPAD array, capable of a time resolution of 10-5-10-6 s for full frames while retaining acceptable photosensitivity thanks to the use of dedicated microlenses, in a selective plane illumination-fluorescence correlation spectroscopy setup. The latter allows us to perform thousands of fluorescence-correlation spectroscopy measurements simultaneously in a two-dimensional slice of the sample. This high-speed SPAD imager enables the measurement of molecular motion of small fluorescent particles such as single chemical dye molecules. Inhomogeneities in the molecular detection efficiency were compensated for by means of a global fit of the auto- and cross-correlation curves, which also made a calibration-free measurement of various samples possible. The afterpulsing effect could also be mitigated, making the measurement of the diffusion of Alexa-488 possible, and the overall result quality was further improved by spatial binning. The particle concentrations in the focus tend to be overestimated by a factor of 1.7 compared to a confocal setup; a calibration is thus required if absolute concentrations need to be measured. The first high-speed selective plane illumination-fluorescence correlation spectroscopy in vivo measurements to our knowledge were also recorded: although two-component fit models could not be employed because of noise, the diffusion of eGFP oligomers in HeLa cells could be measured. Sensitivity and noise will be further improved in the next generation of SPAD-based widefield sensors, which are currently under testing.
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Affiliation(s)
- Jan Buchholz
- German Cancer Research Center, Heidelberg, Germany
| | - Jan Krieger
- German Cancer Research Center, Heidelberg, Germany
| | | | - Samuel Burri
- École polytechnique fédérale de Lausanne, Lausanne, Switzerland
| | - Andrei Ardelean
- École polytechnique fédérale de Lausanne, Lausanne, Switzerland
| | - Edoardo Charbon
- École polytechnique fédérale de Lausanne, Lausanne, Switzerland
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Homulle H, Visser S, Patra B, Charbon E. Design techniques for a stable operation of cryogenic field-programmable gate arrays. Rev Sci Instrum 2018; 89:014703. [PMID: 29390695 DOI: 10.1063/1.5004484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 12/09/2017] [Indexed: 06/07/2023]
Abstract
In this paper, we show how a deep-submicron field-programmable gate array (FPGA) can be operated more stably at extremely low temperatures through special firmware design techniques. Stability at low temperatures is limited through long power supply wires and reduced performance of various printed circuit board components commonly employed at room temperature. Extensive characterization of these components shows that the majority of decoupling capacitor types and voltage regulators are not well behaved at cryogenic temperatures, asking for an ad hoc solution to stabilize the FPGA supply voltage, especially for sensitive applications. Therefore, we have designed a firmware that enforces a constant power consumption, so as to stabilize the supply voltage in the interior of the FPGA. The FPGA is powered with a supply at several meters distance, causing significant resistive voltage drop and thus fluctuations on the local supply voltage. To achieve the stabilization, the variation in digital logic speed, which directly corresponds to changes in supply voltage, is constantly measured and corrected for through a tunable oscillator farm, implemented on the FPGA. The impact of the stabilization technique is demonstrated together with a reconfigurable analog-to-digital converter (ADC), completely implemented in the FPGA fabric and operating at 15 K. The ADC performance can be improved by at most 1.5 bits (effective number of bits) thanks to the more stable supply voltage. The method is versatile and robust, enabling seamless porting to other FPGA families and configurations.
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Affiliation(s)
- Harald Homulle
- QuTech, Delft University of Technology, 2628CD Delft, The Netherlands
| | - Stefan Visser
- QuTech, Delft University of Technology, 2628CD Delft, The Netherlands
| | - Bishnu Patra
- QuTech, Delft University of Technology, 2628CD Delft, The Netherlands
| | - Edoardo Charbon
- QuTech, Delft University of Technology, 2628CD Delft, The Netherlands
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49
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Homulle H, Visser S, Patra B, Ferrari G, Prati E, Sebastiano F, Charbon E. A reconfigurable cryogenic platform for the classical control of quantum processors. Rev Sci Instrum 2017; 88:045103. [PMID: 28456245 DOI: 10.1063/1.4979611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The implementation of a classical control infrastructure for large-scale quantum computers is challenging due to the need for integration and processing time, which is constrained by coherence time. We propose a cryogenic reconfigurable platform as the heart of the control infrastructure implementing the digital error-correction control loop. The platform is implemented on a field-programmable gate array (FPGA) that supports the functionality required by several qubit technologies and that can operate close to the physical qubits over a temperature range from 4 K to 300 K. This work focuses on the extensive characterization of the electronic platform over this temperature range. All major FPGA building blocks (such as look-up tables (LUTs), carry chains (CARRY4), mixed-mode clock manager (MMCM), phase-locked loop (PLL), block random access memory, and IDELAY2 (programmable delay element)) operate correctly and the logic speed is very stable. The logic speed of LUTs and CARRY4 changes less then 5%, whereas the jitter of MMCM and PLL clock managers is reduced by 20%. The stability is finally demonstrated by operating an integrated 1.2 GSa/s analog-to-digital converter (ADC) with a relatively stable performance over temperature. The ADCs effective number of bits drops from 6 to 4.5 bits when operating at 15 K.
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Affiliation(s)
- Harald Homulle
- QuTech, Delft University of Technology, 2628CD Delft, The Netherlands
| | - Stefan Visser
- QuTech, Delft University of Technology, 2628CD Delft, The Netherlands
| | - Bishnu Patra
- QuTech, Delft University of Technology, 2628CD Delft, The Netherlands
| | | | - Enrico Prati
- Istituto di Fotonica e Nanotecnologie, 20133 Milan, Italy
| | - Fabio Sebastiano
- QuTech, Delft University of Technology, 2628CD Delft, The Netherlands
| | - Edoardo Charbon
- QuTech, Delft University of Technology, 2628CD Delft, The Netherlands
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50
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Nikzad S, Hoenk M, Jewell AD, Hennessy JJ, Carver AG, Jones TJ, Goodsall TM, Hamden ET, Suvarna P, Bulmer J, Shahedipour-Sandvik F, Charbon E, Padmanabhan P, Hancock B, Bell LD. Single Photon Counting UV Solar-Blind Detectors Using Silicon and III-Nitride Materials. Sensors (Basel) 2016; 16:s16060927. [PMID: 27338399 PMCID: PMC4934352 DOI: 10.3390/s16060927] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/05/2016] [Accepted: 06/07/2016] [Indexed: 11/16/2022]
Abstract
Ultraviolet (UV) studies in astronomy, cosmology, planetary studies, biological and medical applications often require precision detection of faint objects and in many cases require photon-counting detection. We present an overview of two approaches for achieving photon counting in the UV. The first approach involves UV enhancement of photon-counting silicon detectors, including electron multiplying charge-coupled devices and avalanche photodiodes. The approach used here employs molecular beam epitaxy for delta doping and superlattice doping for surface passivation and high UV quantum efficiency. Additional UV enhancements include antireflection (AR) and solar-blind UV bandpass coatings prepared by atomic layer deposition. Quantum efficiency (QE) measurements show QE > 50% in the 100–300 nm range for detectors with simple AR coatings, and QE ≅ 80% at ~206 nm has been shown when more complex AR coatings are used. The second approach is based on avalanche photodiodes in III-nitride materials with high QE and intrinsic solar blindness.
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Affiliation(s)
- Shouleh Nikzad
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
| | - Michael Hoenk
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
| | - April D Jewell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
| | - John J Hennessy
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
| | - Alexander G Carver
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
| | - Todd J Jones
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
| | - Timothy M Goodsall
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
| | - Erika T Hamden
- Department of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA.
| | - Puneet Suvarna
- College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, Albany, NY 12203, USA.
| | - J Bulmer
- College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, Albany, NY 12203, USA.
| | - F Shahedipour-Sandvik
- College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, Albany, NY 12203, USA.
| | - Edoardo Charbon
- Department of Microelectronics, Delft University of Technology, Delft, The Netherlands.
| | - Preethi Padmanabhan
- Department of Microelectronics, Delft University of Technology, Delft, The Netherlands.
| | - Bruce Hancock
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
| | - L Douglas Bell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
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