1
|
He M, Shen X, Liu X, Kuang C, Liu X. 3D nanoprinting for fiber-integrated achromatic diffractive lens. OPTICS LETTERS 2023; 48:5221-5224. [PMID: 37831832 DOI: 10.1364/ol.501356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 09/12/2023] [Indexed: 10/15/2023]
Abstract
Achromatic performance is crucial for numerous multi-wavelength optical fiber applications, including endoscopic imaging and fiber sensing. This paper presents the design and nanoprinting of a fiber-integrated achromatic diffractive lens within the visible spectrum (450-650 nm). The 3D nanoprinting is achieved by a high-resolution direct laser writing technology, overcoming limitations in the optical performance caused by the lack of an arbitrary 3D structure writing capability and an insufficient feature resolution in the current manufacturing technology for visible light broadband achromatic diffractive lenses. A three-step optimization algorithm is proposed to effectively balance optical performance with writing difficulty. The characterization results demonstrate excellent achromatic focusing performance, paving the way towards the development of nanoprinted flat optical devices for applications such as optical fiber traps, miniature illumination systems, and integrated photonic chips.
Collapse
|
2
|
Dong Y, Shen H, Xu Y, Zhang B. Compact and broadband design of an 850 nm 2 × 2 3-dB directional coupler with a shallowly etched SWG gap. APPLIED OPTICS 2022; 61:9154-9162. [PMID: 36607048 DOI: 10.1364/ao.471114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 10/04/2022] [Indexed: 06/17/2023]
Abstract
A compact and broadband 2×2 3 dB directional coupler (DC) is designed at the 850 nm wavelength region based on the silicon nitride platform. The proposed DC is equipped with a shallowly etched subwavelength gratings (SWG) gap so that the length of the coupling region is effectively reduced to 7.8 µm for equally splitting the fundamental TE polarization state. Such a DC coupling region is much more compact than that using empty and pure SWG gaps. Meanwhile, the DC working bandwidth is determined to be broader than 106 nm, and the insertion loss is always kept under an acceptable level of 0.6 dB over the entire wavelength region. Considering that the shallowly etched device requires two photoetching processes in manufacturing, we did a numerical analysis to characterize the fabrication tolerance under a minimum overlay accuracy of 20 nm in both x and y directions. Such overlay mismatch only increases the maximal imbalance from 0.55 to 0.6 dB at the center wavelength. In addition, we discussed the impact of the proposed DC in its potential application, i.e., optical coherence tomography. The results show that the proposed DC is able to support a high axial resolution of 3.77 µm, and the 20 nm overlay mismatch leads to neglected axial resolution degradation.
Collapse
|
3
|
Nesic A, Blaicher M, Orlandini E, Olariu T, Paszkiewicz M, Negredo F, Kraft P, Sukhova M, Hofmann A, Dörfler W, Rockstuhl C, Freude W, Koos C. Transformation-optics modeling of 3D-printed freeform waveguides. OPTICS EXPRESS 2022; 30:38856-38879. [PMID: 36258441 DOI: 10.1364/oe.452243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 04/23/2022] [Indexed: 06/16/2023]
Abstract
Multi-photon lithography allows us to complement planar photonic integrated circuits (PIC) by in-situ 3D-printed freeform waveguide structures. However, design and optimization of such freeform waveguides using time-domain Maxwell's equations solvers often requires comparatively large computational volumes, within which the structure of interest only occupies a small fraction, thus leading to poor computational efficiency. In this paper, we present a solver-independent transformation-optics-(TO-) based technique that allows to greatly reduce the computational effort related to modeling of 3D freeform waveguides. The concept relies on transforming freeform waveguides with curved trajectories into equivalent waveguide structures with modified material properties but geometrically straight trajectories, that can be efficiently fit into rather small cuboid-shaped computational volumes. We demonstrate the viability of the technique and benchmark its performance using a series of different freeform waveguides, achieving a reduction of the simulation time by a factor of 3-6 with a significant potential for further improvement. We also fabricate and experimentally test the simulated waveguides by 3D-printing on a silicon photonic chip, and we find good agreement between the simulated and the measured transmission at λ = 1550 nm.
Collapse
|
4
|
Dushaq G, Paredes B, Villegas JE, Tamalampudi SR, Rasras M. On-chip integration of 2D Van der Waals germanium phosphide (GeP) for active silicon photonics devices. OPTICS EXPRESS 2022; 30:15986-15997. [PMID: 36221452 DOI: 10.1364/oe.457242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/11/2022] [Indexed: 06/16/2023]
Abstract
The outstanding performance and facile processability turn two-dimensional materials (2DMs) into the most sought-after class of semiconductors for optoelectronics applications. Yet, significant progress has been made toward the hybrid integration of these materials on silicon photonics (SiPh) platforms for a wide range of mid-infrared (MIR) applications. However, realizing 2D materials with a strong optical response in the NIR-MIR and excellent air stability is still a long-term goal. Here, we report a waveguide integrated photodetector based on a novel 2D GeP. This material uniquely combines narrow and wide tunable bandgap energies (0.51-1.68 eV), offering a broadband operation from visible to MIR spectral range. In a significant advantage over graphene devices, hybrid Si/GeP waveguide photodetectors work under bias with a low dark current of few nano-amps and demonstrate excellent stability and reproducibility. Additionally, 65 nm thick GeP devices integrated on silicon waveguides exhibit a remarkable photoresponsivity of 0.54 A/W and attain high external quantum efficiency of ∼ 51.3% under 1310 nm light and at room temperature. Furthermore, a measured absorption coefficient of 1.54 ± 0.3 dB/µm at 1310 nm suggests the potential of 2D GeP as an alternative infrared material with broad optical tunability and dynamic stability suitable for advanced optoelectronic integration.
Collapse
|
5
|
Trocha P, Kemal JN, Gaimard Q, Aubin G, Lelarge F, Ramdane A, Freude W, Randel S, Koos C. Ultra-fast optical ranging using quantum-dash mode-locked laser diodes. Sci Rep 2022; 12:1076. [PMID: 35058501 PMCID: PMC8776879 DOI: 10.1038/s41598-021-04368-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 11/03/2021] [Indexed: 11/29/2022] Open
Abstract
Laser-based light detection and ranging (LiDAR) is key to many applications in science and industry. For many use cases, compactness and power efficiency are key, especially in high-volume applications such as industrial sensing, navigation of autonomous objects, or digitization of 3D scenes using hand-held devices. In this context, comb-based ranging systems are of particular interest, combining high accuracy with high measurement speed. However, the technical complexity of miniaturized comb sources is still prohibitive for many applications, in particular when high optical output powers and high efficiency are required. Here we show that quantum-dash mode-locked laser diodes (QD-MLLD) offer a particularly attractive route towards high-performance chip-scale ranging systems. QD-MLLDs are compact, can be easily operated by a simple DC drive current, and provide spectrally flat frequency combs with bandwidths in excess of 2 THz, thus lending themselves to coherent dual-comb ranging. In our experiments, we show measurement rates of up to 500 MHz—the highest rate demonstrated with any ranging system so far. We attain reliable measurement results with optical return powers of only – 40 dBm, corresponding to a total loss of 49 dB in the ranging path, which corresponds to the highest loss tolerance demonstrated so far for dual-comb ranging with chip-scale comb sources. Combing QD-MLLDs with advanced silicon photonic receivers offers an attractive route towards robust and technically simple chip-scale LiDAR systems.
Collapse
|
6
|
Rank EA, Agneter A, Schmoll T, Leitgeb RA, Drexler W. Miniaturizing optical coherence tomography. TRANSLATIONAL BIOPHOTONICS 2022. [DOI: 10.1002/tbio.202100007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Elisabet A. Rank
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| | - Anja Agneter
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| | - Tilman Schmoll
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
- Carl Zeiss Meditec, Inc. Dublin California USA
| | - Rainer A. Leitgeb
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| | - Wolfgang Drexler
- Center for Medical Physics and Biomedical Engineering Medical University of Vienna Vienna Austria
| |
Collapse
|
7
|
In vivo human retinal swept source optical coherence tomography and angiography at 830 nm with a CMOS compatible photonic integrated circuit. Sci Rep 2021; 11:21052. [PMID: 34702941 PMCID: PMC8548589 DOI: 10.1038/s41598-021-00637-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/15/2021] [Indexed: 11/29/2022] Open
Abstract
Photonic integrated circuits (PIC) provide promising functionalities to significantly reduce the size and costs of optical coherence tomography (OCT) systems. This paper presents an imaging platform operating at a center wavelength of 830 nm for ophthalmic application using PIC-based swept source OCT. An on-chip Mach–Zehnder interferometer (MZI) configuration, which comprises an input power splitter, polarization beam splitters in the sample and the reference arm, and a 50/50 coupler for signal interference represents the core element of the system with a footprint of only \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$(12 \times 5)\;{\text {mm}}^2$$\end{document}(12×5)mm2. The system achieves 94 dB imaging sensitivity with 750 \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\upmu $$\end{document}μW on the sample, 50 kHz imaging speed and 5.5 \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\upmu $$\end{document}μm axial resolution (in soft tissue). With this setup, in vivo human retinal imaging of healthy subjects was performed producing B-scans, three-dimensional renderings as well as OCT angiography. These promising results are significant prerequisites for further integration of optical and electronic building blocks on a single swept source-OCT PIC.
Collapse
|
8
|
Leitgeb R, Placzek F, Rank E, Krainz L, Haindl R, Li Q, Liu M, Andreana M, Unterhuber A, Schmoll T, Drexler W. Enhanced medical diagnosis for dOCTors: a perspective of optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-210150-PER. [PMID: 34672145 PMCID: PMC8528212 DOI: 10.1117/1.jbo.26.10.100601] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 09/23/2021] [Indexed: 05/17/2023]
Abstract
SIGNIFICANCE After three decades, more than 75,000 publications, tens of companies being involved in its commercialization, and a global market perspective of about USD 1.5 billion in 2023, optical coherence tomography (OCT) has become one of the fastest successfully translated imaging techniques with substantial clinical and economic impacts and acceptance. AIM Our perspective focuses on disruptive forward-looking innovations and key technologies to further boost OCT performance and therefore enable significantly enhanced medical diagnosis. APPROACH A comprehensive review of state-of-the-art accomplishments in OCT has been performed. RESULTS The most disruptive future OCT innovations include imaging resolution and speed (single-beam raster scanning versus parallelization) improvement, new implementations for dual modality or even multimodality systems, and using endogenous or exogenous contrast in these hybrid OCT systems targeting molecular and metabolic imaging. Aside from OCT angiography, no other functional or contrast enhancing OCT extension has accomplished comparable clinical and commercial impacts. Some more recently developed extensions, e.g., optical coherence elastography, dynamic contrast OCT, optoretinography, and artificial intelligence enhanced OCT are also considered with high potential for the future. In addition, OCT miniaturization for portable, compact, handheld, and/or cost-effective capsule-based OCT applications, home-OCT, and self-OCT systems based on micro-optic assemblies or photonic integrated circuits will revolutionize new applications and availability in the near future. Finally, clinical translation of OCT including medical device regulatory challenges will continue to be absolutely essential. CONCLUSIONS With its exquisite non-invasive, micrometer resolution depth sectioning capability, OCT has especially revolutionized ophthalmic diagnosis and hence is the fastest adopted imaging technology in the history of ophthalmology. Nonetheless, OCT has not been completely exploited and has substantial growth potential-in academics as well as in industry. This applies not only to the ophthalmic application field, but also especially to the original motivation of OCT to enable optical biopsy, i.e., the in situ imaging of tissue microstructure with a resolution approaching that of histology but without the need for tissue excision.
Collapse
Affiliation(s)
- Rainer Leitgeb
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
- Medical University of Vienna, Christian Doppler Laboratory OPTRAMED, Vienna, Austria
| | - Fabian Placzek
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Elisabet Rank
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Lisa Krainz
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Richard Haindl
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Qian Li
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Mengyang Liu
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Marco Andreana
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Angelika Unterhuber
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Tilman Schmoll
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
- Carl Zeiss Meditec, Inc., Dublin, California, United States
| | - Wolfgang Drexler
- Medical University of Vienna, Center for Medical Physics and Biomedical Engineering, Vienna, Austria
- Address all correspondence to Wolfgang Drexler,
| |
Collapse
|
9
|
Ji X, Mojahed D, Okawachi Y, Gaeta AL, Hendon CP, Lipson M. Millimeter-scale chip-based supercontinuum generation for optical coherence tomography. SCIENCE ADVANCES 2021; 7:eabg8869. [PMID: 34533990 PMCID: PMC8448444 DOI: 10.1126/sciadv.abg8869] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Supercontinuum sources for optical coherence tomography (OCT) have raised great interest as they provide broad bandwidth to enable high resolution and high power to improve imaging sensitivity. Commercial fiber-based supercontinuum systems require high pump powers to generate broad bandwidth and customized optical filters to shape/attenuate the spectra. They also have limited sensitivity and depth performance. We introduce a supercontinuum platform based on a 1-mm2 Si3N4 photonic chip for OCT. We directly pump and efficiently generate supercontinuum near 1300 nm without any postfiltering. With a 25-pJ pump pulse, we generate a broadband spectrum with a flat 3-dB bandwidth of 105 nm. Integrating the chip into a spectral domain OCT system, we achieve 105-dB sensitivity and 1.81-mm 6-dB sensitivity roll-off with 300-μW optical power on sample. We image breast tissue to demonstrate strong imaging performance. Our chip will pave the way toward portable OCT and incorporating integrated photonics into optical imaging technologies.
Collapse
Affiliation(s)
- Xingchen Ji
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA
| | - Diana Mojahed
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
| | - Yoshitomo Okawachi
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10027, USA
| | - Alexander L. Gaeta
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10027, USA
| | - Christine P. Hendon
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA
- Corresponding author. (M.L.); (C.P.H.)
| | - Michal Lipson
- Department of Electrical Engineering, Columbia University, New York, NY 10027, USA
- Corresponding author. (M.L.); (C.P.H.)
| |
Collapse
|
10
|
Rank EA, Sentosa R, Harper DJ, Salas M, Gaugutz A, Seyringer D, Nevlacsil S, Maese-Novo A, Eggeling M, Muellner P, Hainberger R, Sagmeister M, Kraft J, Leitgeb RA, Drexler W. Toward optical coherence tomography on a chip: in vivo three-dimensional human retinal imaging using photonic integrated circuit-based arrayed waveguide gratings. LIGHT, SCIENCE & APPLICATIONS 2021; 10:6. [PMID: 33402664 PMCID: PMC7785745 DOI: 10.1038/s41377-020-00450-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 11/14/2020] [Accepted: 12/03/2020] [Indexed: 05/19/2023]
Abstract
In this work, we present a significant step toward in vivo ophthalmic optical coherence tomography and angiography on a photonic integrated chip. The diffraction gratings used in spectral-domain optical coherence tomography can be replaced by photonic integrated circuits comprising an arrayed waveguide grating. Two arrayed waveguide grating designs with 256 channels were tested, which enabled the first chip-based optical coherence tomography and angiography in vivo three-dimensional human retinal measurements. Design 1 supports a bandwidth of 22 nm, with which a sensitivity of up to 91 dB (830 µW) and an axial resolution of 10.7 µm was measured. Design 2 supports a bandwidth of 48 nm, with which a sensitivity of 90 dB (480 µW) and an axial resolution of 6.5 µm was measured. The silicon nitride-based integrated optical waveguides were fabricated with a fully CMOS-compatible process, which allows their monolithic co-integration on top of an optoelectronic silicon chip. As a benchmark for chip-based optical coherence tomography, tomograms generated by a commercially available clinical spectral-domain optical coherence tomography system were compared to those acquired with on-chip gratings. The similarities in the tomograms demonstrate the significant clinical potential for further integration of optical coherence tomography on a chip system.
Collapse
Affiliation(s)
- Elisabet A Rank
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4 L, 1090, Vienna, Austria.
| | - Ryan Sentosa
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4 L, 1090, Vienna, Austria
| | - Danielle J Harper
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4 L, 1090, Vienna, Austria
| | - Matthias Salas
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4 L, 1090, Vienna, Austria
| | - Anna Gaugutz
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4 L, 1090, Vienna, Austria
| | - Dana Seyringer
- Research Centre for Microtechnology, Vorarlberg University of Applied Sciences, Hochschulstrasse 1, 6850, Dornbirn, Austria
| | - Stefan Nevlacsil
- AIT Austrian Institute of Technology GmbH, Gieffinggasse 4, 1210, Vienna, Austria
| | - Alejandro Maese-Novo
- AIT Austrian Institute of Technology GmbH, Gieffinggasse 4, 1210, Vienna, Austria
| | - Moritz Eggeling
- AIT Austrian Institute of Technology GmbH, Gieffinggasse 4, 1210, Vienna, Austria
| | - Paul Muellner
- AIT Austrian Institute of Technology GmbH, Gieffinggasse 4, 1210, Vienna, Austria
| | - Rainer Hainberger
- AIT Austrian Institute of Technology GmbH, Gieffinggasse 4, 1210, Vienna, Austria
| | | | - Jochen Kraft
- ams AG, Tobelbader Strasse 30, 8141, Premstaetten, Austria
| | - Rainer A Leitgeb
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4 L, 1090, Vienna, Austria
| | - Wolfgang Drexler
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Waehringer Guertel 18-20/4 L, 1090, Vienna, Austria
| |
Collapse
|
11
|
Jayakumar N, Helle ØI, Agarwal K, Ahluwalia BS. On-chip TIRF nanoscopy by applying Haar wavelet kernel analysis on intensity fluctuations induced by chip illumination. OPTICS EXPRESS 2020; 28:35454-35468. [PMID: 33379659 DOI: 10.1364/oe.403804] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 10/11/2020] [Indexed: 06/12/2023]
Abstract
Photonic-chip based TIRF illumination has been used to demonstrate several on-chip optical nanoscopy methods. The sample is illuminated by the evanescent field generated by the electromagnetic wave modes guided inside the optical waveguide. In addition to the photokinetics of the fluorophores, the waveguide modes can be further exploited for introducing controlled intensity fluctuations for exploitation by techniques such as super-resolution optical fluctuation imaging (SOFI). However, the problem of non-uniform illumination pattern generated by the modes contribute to artifacts in the reconstructed image. To alleviate this problem, we propose to perform Haar wavelet kernel (HAWK) analysis on the original image stack prior to the application of (SOFI). HAWK produces a computational image stack with higher spatio-temporal sparsity than the original stack. In the case of multimoded non-uniform illumination patterns, HAWK processing breaks the mode pattern while introducing spatio-temporal sparsity, thereby differentially affecting the non-uniformity of the illumination. Consequently, this assists nanoscopy methods such as SOFI to better support super-resolution, which is otherwise compromised due to spatial correlation of the mode patterns in the raw image. Furthermore, applying HAWK prior to SOFI alleviates the problem of artifacts due to non-uniform illumination without degrading temporal resolution. Our experimental results demonstrate resolution enhancement as well as reduction in artifacts through the combination of HAWK and SOFI.
Collapse
|
12
|
Nevlacsil S, Muellner P, Maese-Novo A, Eggeling M, Vogelbacher F, Sagmeister M, Kraft J, Rank E, Drexler W, Hainberger R. Multi-channel swept source optical coherence tomography concept based on photonic integrated circuits. OPTICS EXPRESS 2020; 28:32468-32482. [PMID: 33114932 DOI: 10.1364/oe.404588] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 10/05/2020] [Indexed: 05/28/2023]
Abstract
In this paper, we present a novel concept for a multi-channel swept source optical coherence tomography (OCT) system based on photonic integrated circuits (PICs). At the core of this concept is a low-loss polarization dependent path routing approach allowing for lower excess loss compared to previously shown PIC-based OCT systems, facilitating a parallelization of measurement units. As a proof of concept for the low-loss path routing, a silicon nitride PIC-based single-channel swept source OCT system operating at 840 nm was implemented and used to acquire in-vivo tomograms of a human retina. The fabrication of the PIC was done via CMOS-compatible plasma-enhanced chemical vapor deposition to allow future monolithic co-integration with photodiodes and read-out electronics. A performance analysis using the results of the implemented photonic building blocks shows a potential tenfold increase of the acquisition speed for a multi-channel system compared to an ideal lossless single-channel system with the same signal-to-noise ratio.
Collapse
|
13
|
Lu Y, Cao V, Liao M, Li W, Tang M, Li A, Smowton P, Seeds A, Liu H, Chen S. Electrically pumped continuous-wave O-band quantum-dot superluminescent diode on silicon. OPTICS LETTERS 2020; 45:5468-5471. [PMID: 33001927 DOI: 10.1364/ol.401042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 08/03/2020] [Indexed: 06/11/2023]
Abstract
High-power, broadband quantum-dot (QD) superluminescent diodes (SLDs) are ideal light sources for optical coherence tomography (OCT) imaging systems but have previously mainly been fabricated on native GaAs- or InP-based substrates. Recently, significant progress has been made to emigrate QD SLDs from native substrates to silicon substrates. Here, we demonstrate electrically pumped continuous-wave InAs QD SLDs monolithically grown on silicon substrates with significantly improved performance thanks to the achievement of a low density of defects in the III-V epilayers. The fabricated narrow-ridge-waveguide device exhibits a maximum 3 dB bandwidth of 103 nm emission spectrum centered at the O-band together with a maximum single facet output power of 3.8 mW at room temperature. The silicon-based SLD has been assessed for application in an OCT system. Under optimized conditions, a predicted axial resolution of ∼5.3µm is achieved with a corresponding output power of 0.66 mW/facet.
Collapse
|
14
|
Jovic A, Losilla NS, Durá JS, Zinoviev K, Rubio Guivernau JL, Margallo-Balbás E, Mastrangeli M, Pandraud G, Sarro PM. Self-aligned micro-optic integrated photonic platform. APPLIED OPTICS 2020; 59:180-189. [PMID: 32225286 DOI: 10.1364/ao.59.000180] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 11/19/2019] [Indexed: 06/10/2023]
Abstract
In this work, we present the fabrication technology of a monolithically integrated photonic platform combining key components for optical coherence tomography (OCT) imaging, thereby including a photonic interferometer, a collimating lens, and a 45° reflecting mirror that directs the light from the interferometer to the collimator. The proposed integration process simplifies the fabrication of an interferometric system and inherently overcomes the complexity of costly alignment procedures while complying with the necessarily stringent optical constraints. Fabricated waveguide characterization shows total optical losses as low as 3 dB, and less than 1 dB of additional loss due to the Si 45° mirror facet. The alignment standard deviation of all components is within 15 nm. The integrated lens profile achieves a divergence angle smaller than 0.7°, which is close to that of a collimator. The proposed photonic platform provides the premise for low-cost and small-footprint single-chip OCT systems.
Collapse
|
15
|
Ji X, Yao X, Klenner A, Gan Y, Gaeta AL, Hendon CP, Lipson M. Chip-based frequency comb sources for optical coherence tomography. OPTICS EXPRESS 2019; 27:19896-19905. [PMID: 31503744 DOI: 10.1364/oe.27.019896] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 06/15/2019] [Indexed: 06/10/2023]
Abstract
Optical coherence tomography (OCT) is a powerful interferometric imaging technique widely used in medical fields such as ophthalmology, cardiology and dermatology. Superluminescent diodes (SLDs) are widely used as light sources in OCT. Recently integrated chip-based frequency combs have been demonstrated in numerous platforms and the possibility of using these broadband chip-scale combs for OCT has been raised extensively over the past few years. However, the use of these chip-based frequency combs as light sources for OCT requires bandwidth and power compatibility with current OCT systems and have not been shown to date. Here we generate frequency combs based on chip-scale lithographically-defined microresonators and demonstrate its capability as a novel light source for OCT. The combs are designed with a small spectral line spacing of 0.21 nm which ensure imaging range comparable to commercial system and operated at non-phase locked regime which provide conversion efficiency of 30%. The comb source is shown to be compatible with a standard commercial spectral domain (SD) OCT system and enables imaging of human tissue with image quality comparable to the one achieved with tabletop commercial sources. The comb source also provides a path towards fully integrated OCT systems.
Collapse
|
16
|
Yamanari M, Uematsu S, Ishihara K, Ikuno Y. Parallel detection of Jones-matrix elements in polarization-sensitive optical coherence tomography. BIOMEDICAL OPTICS EXPRESS 2019; 10:2318-2336. [PMID: 31149375 PMCID: PMC6524579 DOI: 10.1364/boe.10.002318] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/16/2019] [Accepted: 03/18/2019] [Indexed: 06/09/2023]
Abstract
The polarization properties of a sample can be characterized using a Jones matrix. To measure the Jones matrix without assumptions of the sample, two different incident states of polarization are usually used. This requirement often causes certain drawbacks in polarization-sensitive optical coherence tomography (PS-OCT), e.g., a decrease in the effective A-scan rate or axial depth range, if a multiplexing scheme is used. Because both the A-scan rate and axial depth range are important for clinical applications, including the imaging of an anterior eye segment, a new PS-OCT method that does not have these drawbacks is desired. Here, we present a parallel-detection approach that maintains the same A-scan rate and axial measurement range as conventional OCT. The interferometer consists of fiber-optic components, most of which are polarization-maintaining components with fast-axis blocking free from polarization management. When a parallel detection is implemented using swept-source OCT (SS-OCT), synchronization between the A-scans and synchronization between the detection channels have critical effects on the Jones-matrix measurement. Because it is difficult to achieve perfect synchronization using only hardware, we developed a solution using a numerical correction with signals from a static mirror. Using the developed system, we demonstrate the imaging of an anterior eye segment from the cornea to the back surface of the crystalline lens.
Collapse
Affiliation(s)
- Masahiro Yamanari
- Engineering Department, Tomey Corporation, 2-11-33 Noritakeshinmachi, Nishiku, Nagoya, Aichi, 451-0051, Japan
| | - Sato Uematsu
- Department of Ophthalmology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Kenji Ishihara
- Engineering Department, Tomey Corporation, 2-11-33 Noritakeshinmachi, Nishiku, Nagoya, Aichi, 451-0051, Japan
| | - Yasushi Ikuno
- Ikuno Eye Center, 2-9-10 3F Juso-Higashi, Yodogawaku, Osaka, Osaka, 532-0023, Japan
| |
Collapse
|
17
|
Wang J, Long Y. On-chip silicon photonic signaling and processing: a review. Sci Bull (Beijing) 2018; 63:1267-1310. [PMID: 36658865 DOI: 10.1016/j.scib.2018.05.038] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 05/09/2018] [Accepted: 05/15/2018] [Indexed: 01/21/2023]
Abstract
The arrival of the big data era has driven the rapid development of high-speed optical signaling and processing, ranging from long-haul optical communication links to short-reach data centers and high-performance computing, and even micro-/nano-scale inter-chip and intra-chip optical interconnects. On-chip photonic signaling is essential for optical data transmission, especially for chip-scale optical interconnects, while on-chip photonic processing is a critical technology for optical data manipulation or processing, especially at the network nodes to facilitate ultracompact data management with low power consumption. In this paper, we review recent research progress in on-chip photonic signaling and processing on silicon photonics platforms. Firstly, basic key devices (lasers, modulators, detectors) are introduced. Secondly, for on-chip photonic signaling, we present recent works on on-chip data transmission of advanced multi-level modulation signals using various silicon photonic integrated devices (microring, slot waveguide, hybrid plasmonic waveguide, subwavelength grating slot waveguide). Thirdly, for on-chip photonic processing, we summarize recent works on on-chip data processing of advanced multi-level modulation signals exploiting linear and nonlinear effects in different kinds of silicon photonic integrated devices (strip waveguide, directional coupler, 2D grating coupler, microring, silicon-organic hybrid slot waveguide). Various photonic processing functions are demonstrated, such as photonic switch, filtering, polarization/wavelength/mode (de)multiplexing, wavelength conversion, signal regeneration, optical logic and computing. Additionally, we also introduce extended silicon+ photonics and show recent works on on-chip graphene-silicon photonic signal processing. The advances in on-chip silicon photonic signaling and processing with favorable performance pave the way to integrate complete optical communication systems on a monolithic chip and integrate silicon photonics and silicon nanoelectronics on a chip. It is believed that silicon photonics will enable more and more emerging advanced applications even beyond silicon photonic signaling and processing.
Collapse
Affiliation(s)
- Jian Wang
- Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
| | - Yun Long
- Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
| |
Collapse
|
18
|
Sancho-Durá J, Zinoviev K, Lloret-Soler J, Rubio-Guviernau JL, Margallo-Balbás E, Drexler W. Handheld multi-modal imaging for point-of-care skin diagnosis based on akinetic integrated optics optical coherence tomography. JOURNAL OF BIOPHOTONICS 2018; 11:e201800193. [PMID: 29992726 DOI: 10.1002/jbio.201800193] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 07/07/2018] [Indexed: 05/15/2023]
Abstract
A handheld skin imaging system with joint optical coherence tomography (OCT) at 1300 nm and digital epiluminescence microscopy (EM) is presented. The 2 modalities are physically co-registered in a common-path configuration. The instrument is enabled by a dedicated planar lightwave circuit with a footprint of only 1.1 × 19.5 mm2 that provides akinetic axial OCT scanning at speeds up to 24 kHz. Lateral scanning is implemented through a low-voltage Micro Electro-Mechanical System (MEMS) mirror packaged with the axial scanner in a hermetic butterfly module. The OCT system, with a volume of only 80 × 27 × 14 mm3 , achieves an isotropic resolution of ~11 μm in tissue, -93 dB sensitivity, 12 mm lateral field of view, and an axial scanning range of 2.8 mm in air. The complete battery-powered device has a weight of 3 kg in a tablet format, enabling point-of-care use cases. This work shows that integration of complementary imaging modalities through miniaturization technology results in clinically valuable instruments supporting a patient-centered diagnostic imaging workflow.
Collapse
Affiliation(s)
| | | | | | | | | | - Wolfgang Drexler
- Center for Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria
| |
Collapse
|
19
|
Dsouza R, Won J, Monroy GL, Spillman DR, Boppart SA. Economical and compact briefcase spectral-domain optical coherence tomography system for primary care and point-of-care applications. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-11. [PMID: 30251484 PMCID: PMC6170142 DOI: 10.1117/1.jbo.23.9.096003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 08/29/2018] [Indexed: 05/28/2023]
Abstract
Development of low-cost and portable optical coherence tomography (OCT) systems is of global interest in the OCT research community. Such systems enable utility broadly throughout a clinical facility, or in remote areas that often lack clinical infrastructure. We report the development and validation of a low-cost, portable briefcase spectral-domain optical coherence tomography (SD-OCT) system for point-of-care diagnostics in primary care centers and/or in remote settings. The self-contained briefcase OCT contains all associated optical hardware, including light source, spectrometer, hand-held probe, and a laptop. Additionally, this system utilizes unique real-time mosaicking of surface video images that are synchronized with rapid A-scan acquisition to eliminate the need for lateral scanning hardware, and enable the construction of cross-sectional B-mode images over extended lateral distances. The entire briefcase system weighs 9 kg and costs ∼USD$8000 using off-the-shelf components. System performance was validated by acquiring images of in vivo human skin on the fingertip, palm, and nail fold. The efficiency, portability, and low-cost enable accessibility and utility in primary care centers and low-resource settings.
Collapse
Affiliation(s)
- Roshan Dsouza
- University of Illinois at Urbana-Champaign, Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
| | - Jungeun Won
- University of Illinois at Urbana-Champaign, Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Urbana, Illinois, United States
| | - Guillermo L. Monroy
- University of Illinois at Urbana-Champaign, Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Urbana, Illinois, United States
| | - Darold R. Spillman
- University of Illinois at Urbana-Champaign, Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
| | - Stephen A. Boppart
- University of Illinois at Urbana-Champaign, Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Electrical and Computer Engineering, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Carle-Illinois College of Medicine, Urbana, Illinois, United States
| |
Collapse
|
20
|
Tan HEI, Santa Maria PL, Wijesinghe P, Francis Kennedy B, Allardyce BJ, Eikelboom RH, Atlas MD, Dilley RJ. Optical Coherence Tomography of the Tympanic Membrane and Middle Ear: A Review. Otolaryngol Head Neck Surg 2018; 159:424-438. [PMID: 29787354 DOI: 10.1177/0194599818775711] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Objective To evaluate the recent developments in optical coherence tomography (OCT) for tympanic membrane (TM) and middle ear (ME) imaging and to identify what further development is required for the technology to be integrated into common clinical use. Data Sources PubMed, Embase, Google Scholar, Scopus, and Web of Science. Review Methods A comprehensive literature search was performed for English language articles published from January 1966 to January 2018 with the keywords "tympanic membrane or middle ear,""optical coherence tomography," and "imaging." Conclusion Conventional imaging techniques cannot adequately resolve the microscale features of TM and ME, sometimes necessitating diagnostic exploratory surgery in challenging otologic pathology. As a high-resolution noninvasive imaging technique, OCT offers promise as a diagnostic aid for otologic conditions, such as otitis media, cholesteatoma, and conductive hearing loss. Using OCT vibrometry to image the nanoscale vibrations of the TM and ME as they conduct acoustic waves may detect the location of ossicular chain dysfunction and differentiate between stapes fixation and incus-stapes discontinuity. The capacity of OCT to image depth and thickness at high resolution allows 3-dimensional volumetric reconstruction of the ME and has potential use for reconstructive tympanoplasty planning and the follow-up of ossicular prostheses. Implications for Practice To achieve common clinical use beyond these initial discoveries, future in vivo imaging devices must feature low-cost probe or endoscopic designs and faster imaging speeds and demonstrate superior diagnostic utility to computed tomography and magnetic resonance imaging. While such technology has been available for OCT, its translation requires focused development through a close collaboration between engineers and clinicians.
Collapse
Affiliation(s)
- Hsern Ern Ivan Tan
- 1 Ear Science Institute Australia, Subiaco, Australia.,2 Ear Sciences Centre, School of Medicine, The University of Western Australia, Nedlands, Australia.,3 Department of Otolaryngology-Head and Neck Surgery, Sir Charles Gairdner Hospital, Perth, Australia
| | - Peter Luke Santa Maria
- 1 Ear Science Institute Australia, Subiaco, Australia.,2 Ear Sciences Centre, School of Medicine, The University of Western Australia, Nedlands, Australia.,4 Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California, USA
| | - Philip Wijesinghe
- 5 BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre; Centre for Medical Research, The University of Western Australia, Nedlands, Australia.,6 Department of Electrical, Electronic, and Computer Engineering, School of Engineering, The University of Western Australia, Nedlands, Australia
| | - Brendan Francis Kennedy
- 5 BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre; Centre for Medical Research, The University of Western Australia, Nedlands, Australia.,6 Department of Electrical, Electronic, and Computer Engineering, School of Engineering, The University of Western Australia, Nedlands, Australia
| | | | - Robert Henry Eikelboom
- 1 Ear Science Institute Australia, Subiaco, Australia.,2 Ear Sciences Centre, School of Medicine, The University of Western Australia, Nedlands, Australia.,8 Department of Speech Language Pathology and Audiology, University of Pretoria, Pretoria, South Africa
| | - Marcus David Atlas
- 1 Ear Science Institute Australia, Subiaco, Australia.,2 Ear Sciences Centre, School of Medicine, The University of Western Australia, Nedlands, Australia
| | - Rodney James Dilley
- 1 Ear Science Institute Australia, Subiaco, Australia.,2 Ear Sciences Centre, School of Medicine, The University of Western Australia, Nedlands, Australia
| |
Collapse
|
21
|
Monroy GL, Won J, Spillman DR, Dsouza R, Boppart SA. Clinical translation of handheld optical coherence tomography: practical considerations and recent advancements. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-30. [PMID: 29260539 PMCID: PMC5735247 DOI: 10.1117/1.jbo.22.12.121715] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 12/04/2017] [Indexed: 05/21/2023]
Abstract
Since the inception of optical coherence tomography (OCT), advancements in imaging system design and handheld probes have allowed for numerous advancements in disease diagnostics and characterization of the structural and optical properties of tissue. OCT system developers continue to reduce form factor and cost, while improving imaging performance (speed, resolution, etc.) and flexibility for applicability in a broad range of fields, and nearly every clinical specialty. An extensive array of components to construct customized systems has also become available, with a range of commercial entities that produce high-quality products, from single components to full systems, for clinical and research use. Many advancements in the development of these miniaturized and portable systems can be linked back to a specific challenge in academic research, or a clinical need in medicine or surgery. Handheld OCT systems are discussed and explored for various applications. Handheld systems are discussed in terms of their relative level of portability and form factor, with mention of the supporting technologies and surrounding ecosystem that bolstered their development. Additional insight from our efforts to implement systems in several clinical environments is provided. The trend toward well-designed, efficient, and compact handheld systems paves the way for more widespread adoption of OCT into point-of-care or point-of-procedure applications in both clinical and commercial settings.
Collapse
Affiliation(s)
- Guillermo L. Monroy
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Urbana, Illinois, United States
| | - Jungeun Won
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Urbana, Illinois, United States
| | - Darold R. Spillman
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
| | - Roshan Dsouza
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
| | - Stephen A. Boppart
- Beckman Institute for Advanced Science and Technology, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Bioengineering, Urbana, Illinois, United States
- University of Illinois at Urbana-Champaign, Department of Electrical and Computer Engineering, Urbana, Illinois, United States
- Carle-Illinois College of Medicine, Urbana, Illinois, United States
- Address all correspondence to: Stephen A. Boppart, E-mail:
| |
Collapse
|
22
|
Weimann C, Lauermann M, Hoeller F, Freude W, Koos C. Silicon photonic integrated circuit for fast and precise dual-comb distance metrology. OPTICS EXPRESS 2017; 25:30091-30104. [PMID: 29221043 DOI: 10.1364/oe.25.030091] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 09/15/2017] [Indexed: 06/07/2023]
Abstract
We demonstrate an optical distance sensor integrated on a silicon photonic chip with a footprint of well below 1 mm2. The integrated system comprises a heterodyne receiver structure with tunable power splitting ratio and on-chip photodetectors. The functionality of the device is demonstrated in a synthetic-wavelength interferometry experiment using frequency combs as optical sources. We obtain accurate and fast distance measurements with an unambiguity range of 3.75 mm, a root-mean-square error of 3.4 µm and acquisition times of 14 µs.
Collapse
|
23
|
Neuhaus K, O'Gorman S, McNamara PM, Alexandrov S, Hogan J, Wilson C, Leahy MJ. Simultaneous en-face imaging of multiple layers with multiple reference optical coherence tomography. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-7. [PMID: 28831794 DOI: 10.1117/1.jbo.22.8.086006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 07/24/2017] [Indexed: 05/24/2023]
Abstract
A technique based on multiple reference optical coherence tomography (MR-OCT) is proposed for simultaneous imaging at multiple depths. The technique has been validated by imaging a reference sample and a fingerprint in-vivo. The principle of scanning multiple selected layers is shown by imaging a partial fingerprint with 200×200×200 voxels of 3×3×0.5 mm size and obtaining an arbitrary amount of layers merely by digital processing. The spacing among the layers can be adjusted arbitrarily, and the SNR roll-off is shown for three different spacings. At a mirror scan frequency of 1 kHz and an A-line rate of 2 kHz, the acquisition time was 20 s for one volume. The results show the feasibility of the application of layer scanning MR-OCT that uses a partial mirror in the reference arm of the Michelson interferometer. The reduced scan range required for layer scanning allows even higher scan rates that are limited only by the voice coil design and the mass-spring system, e.g., mirror mass, spring constant, and damping.
Collapse
Affiliation(s)
- Kai Neuhaus
- National University of Ireland, Tissue Optics and Microcirculation Imaging Facility, Galway, Ireland
| | - Seán O'Gorman
- National University of Ireland, Tissue Optics and Microcirculation Imaging Facility, Galway, Ireland
| | - Paul M McNamara
- National University of Ireland, Tissue Optics and Microcirculation Imaging Facility, Galway, Ireland
- Compact Imaging, Inc., Mountain View, California, United States
| | - Sergey Alexandrov
- National University of Ireland, Tissue Optics and Microcirculation Imaging Facility, Galway, Ireland
| | - Josh Hogan
- Compact Imaging, Inc., Mountain View, California, United States
| | - Carol Wilson
- Compact Imaging, Inc., Mountain View, California, United States
| | - Martin J Leahy
- National University of Ireland, Tissue Optics and Microcirculation Imaging Facility, Galway, Ireland
- Royal College of Surgeons, Dublin, Ireland
| |
Collapse
|
24
|
Schneider S, Eppler F, Weber M, Olowojoba G, Weiss P, Hübner C, Mikonsaari I, Freude W, Koos C. Multiscale dispersion-state characterization of nanocomposites using optical coherence tomography. Sci Rep 2016; 6:31733. [PMID: 27557544 PMCID: PMC4997610 DOI: 10.1038/srep31733] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 07/22/2016] [Indexed: 11/09/2022] Open
Abstract
Nanocomposite materials represent a success story of nanotechnology. However,
development of nanomaterial fabrication still suffers from the lack of adequate
analysis tools. In particular, achieving and maintaining well-dispersed particle
distributions is a key challenge, both in material development and industrial
production. Conventional methods like optical or electron microscopy need laborious,
costly sample preparation and do not permit fast extraction of nanoscale structural
information from statistically relevant sample volumes. Here we show that optical
coherence tomography (OCT) represents a versatile tool for nanomaterial
characterization, both in a laboratory and in a production environment. The
technique does not require sample preparation and is applicable to a wide range of
solid and liquid material systems. Large particle agglomerates can be directly found
by OCT imaging, whereas dispersed nanoparticles are detected by model-based analysis
of depth-dependent backscattering. Using a model system of polystyrene
nanoparticles, we demonstrate nanoparticle sizing with high accuracy. We further
prove the viability of the approach by characterizing highly relevant material
systems based on nanoclays or carbon nanotubes. The technique is perfectly suited
for in-line metrology in a production environment, which is demonstrated using a
state-of-the-art compounding extruder. These experiments represent the first
demonstration of multiscale nanomaterial characterization using OCT.
Collapse
Affiliation(s)
- Simon Schneider
- Institute of Photonics and Quantum Electronics (IPQ), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
| | - Florian Eppler
- Institute of Photonics and Quantum Electronics (IPQ), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
| | - Marco Weber
- Institute of Photonics and Quantum Electronics (IPQ), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany
| | - Ganiu Olowojoba
- Fraunhofer Institute for Chemical Technology (ICT), 76327 Pfinztal, Germany
| | - Patrick Weiss
- Fraunhofer Institute for Chemical Technology (ICT), 76327 Pfinztal, Germany
| | - Christof Hübner
- Fraunhofer Institute for Chemical Technology (ICT), 76327 Pfinztal, Germany
| | - Irma Mikonsaari
- Fraunhofer Institute for Chemical Technology (ICT), 76327 Pfinztal, Germany
| | - Wolfgang Freude
- Institute of Photonics and Quantum Electronics (IPQ), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany.,Institute of Microstructure Technology (IMT), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, German
| | - Christian Koos
- Institute of Photonics and Quantum Electronics (IPQ), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany.,Institute of Microstructure Technology (IMT), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, German
| |
Collapse
|