1
|
Hu L, Wang H, Sawhney K. Spexwavepy: an open-source Python package for X-ray wavefront sensing using speckle-based techniques. JOURNAL OF SYNCHROTRON RADIATION 2024; 31:1037-1042. [PMID: 39078691 PMCID: PMC11371044 DOI: 10.1107/s1600577524005861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 06/17/2024] [Indexed: 07/31/2024]
Abstract
In situ wavefront sensing plays a critical role in the delivery of high-quality beams for X-ray experiments. X-ray speckle-based techniques stand out among other in situ techniques for their easy experimental setup and various data acquisition modes. Although X-ray speckle-based techniques have been under development for more than a decade, there are still no user-friendly software packages for new researchers to begin with. Here, we present an open-source Python package, spexwavepy, for X-ray wavefront sensing using speckle-based techniques. This Python package covers a variety of X-ray speckle-based techniques, provides plenty of examples with real experimental data and offers detailed online documentation for users. We hope it can help new researchers learn and apply the speckle-based techniques for X-ray wavefront sensing to synchrotron radiation and X-ray free-electron laser beamlines.
Collapse
Affiliation(s)
- Lingfei Hu
- National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefeiAnhui230029People’s Republic of China
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOX11 0DEUnited Kingdom
| | - Hongchang Wang
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOX11 0DEUnited Kingdom
| | - Kawal Sawhney
- Diamond Light SourceHarwell Science and Innovation CampusDidcotOX11 0DEUnited Kingdom
| |
Collapse
|
2
|
Zhou T, Hu L, Wang H. At-wavelength metrology of an X-ray mirror using a downstream wavefront modulator. JOURNAL OF SYNCHROTRON RADIATION 2024; 31:432-437. [PMID: 38587895 DOI: 10.1107/s1600577524002157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 03/06/2024] [Indexed: 04/09/2024]
Abstract
At-wavelength metrology of X-ray optics plays a crucial role in evaluating the performance of optics under actual beamline operating conditions, enabling in situ diagnostics and optimization. Techniques utilizing a wavefront random modulator have gained increasing attention in recent years. However, accurately mapping the measured wavefront slope to a curved X-ray mirror surface when the modulator is downstream of the mirror has posed a challenge. To address this problem, an iterative method has been developed in this study. The results demonstrate a significant improvement compared with conventional approaches and agree with offline measurements obtained from optical metrology. We believe that the proposed method enhances the accuracy of at-wavelength metrology techniques, and empowers them to play a greater role in beamline operation and optics fabrication.
Collapse
Affiliation(s)
- Tunhe Zhou
- Stockholm University Brain Imaging Centre, Svante Arrhenius väg 16A, Stockholm 11418, Sweden
| | - Lingfei Hu
- Diamond Light Source, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Hongchang Wang
- Diamond Light Source, Didcot, Oxfordshire OX11 0DE, United Kingdom
| |
Collapse
|
3
|
Hu L, Wang H, Fox O, Sawhney K. Two-dimensional speckle technique for slope error measurements of weakly focusing reflective X-ray optics. JOURNAL OF SYNCHROTRON RADIATION 2022; 29:1385-1393. [PMID: 36345746 PMCID: PMC9641570 DOI: 10.1107/s160057752200916x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 09/14/2022] [Indexed: 06/16/2023]
Abstract
Speckle-based at-wavelength metrology techniques now play an important role in X-ray wavefront measurements. However, for reflective X-ray optics, the majority of existing speckle-based methods fail to provide reliable 2D information about the optical surface being characterized. Compared with the 1D information typically output from speckled-based methods, a 2D map is more informative for understanding the overall quality of the optic being tested. In this paper, we propose a method for in situ 2D absolute metrology of weakly focusing X-ray mirrors. Importantly, the angular misalignment of the mirror can be easily corrected with the proposed 2D processing procedure. We hope the speckle pattern data processing method presented here will help to extend this technique to wider applications in the synchrotron radiation and X-ray free-electron laser communities.
Collapse
Affiliation(s)
- Lingfei Hu
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Hongchang Wang
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Oliver Fox
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Kawal Sawhney
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| |
Collapse
|
4
|
Hu L, Wang H, Fox O, Sawhney K. Fast wavefront sensing for X-ray optics with an alternating speckle tracking technique. OPTICS EXPRESS 2022; 30:33259-33273. [PMID: 36242370 DOI: 10.1364/oe.460163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 05/16/2022] [Indexed: 06/16/2023]
Abstract
Advances in accelerator technologies have enabled the continuous development of synchrotron radiation and X-ray free electron laser (XFEL) sources. At the same time, it has been critical to perform in-situ wavefront sensing to aid delivery of high-quality X-ray beams to the end users of these facilities. The speckle-based scanning technique has obtained popularity due to its high spatial resolution and superior sensitivity compared to other wavefront sensing methods. However, these advantages often come at the expense of longer data acquisition times since multiple images have to be collected to derive the necessary wavefront information. Whereas initial speckle tracking techniques could obtain wavefront information relatively quickly, the installation of additional hardware was routinely required to do so. Here, we propose a novel speckle-based approach, termed Alternating Speckle Tracking (AST), to perform fast wavefront sensing within a conventional beamline setup. The wavefront information derived from the new technique has proven to be valuable for many applications that require temporal resolution. Importantly, both horizontal and vertical wavefront information can be simultaneously derived by moving the speckle generator along the diagonal direction. We expect this method will be widely used by the synchrotron radiation and XFEL community in the future.
Collapse
|
5
|
Wang H, Moriconi S, Sawhney K. Nano-precision metrology of X-ray mirrors with laser speckle angular measurement. LIGHT, SCIENCE & APPLICATIONS 2021; 10:195. [PMID: 34552044 PMCID: PMC8458457 DOI: 10.1038/s41377-021-00632-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 08/16/2021] [Accepted: 09/03/2021] [Indexed: 05/25/2023]
Abstract
X-ray mirrors are widely used for synchrotron radiation, free-electron lasers, and astronomical telescopes. The short wavelength and grazing incidence impose strict limits on the permissible slope error. Advanced polishing techniques have already produced mirrors with slope errors below 50 nrad root mean square (rms), but existing metrology techniques struggle to measure them. Here, we describe a laser speckle angular measurement (SAM) approach to overcome such limitations. We also demonstrate that the angular precision of slope error measurements can be pushed down to 20nrad rms by utilizing an advanced sub-pixel tracking algorithm. Furthermore, SAM allows the measurement of mirrors in two dimensions with radii of curvature as low as a few hundred millimeters. Importantly, the instrument based on SAM is compact, low-cost, and easy to integrate with most other existing X-ray mirror metrology instruments, such as the long trace profiler (LTP) and nanometer optical metrology (NOM). The proposed nanometrology method represents an important milestone and potentially opens up new possibilities to develop next-generation super-polished X-ray mirrors, which will advance the development of X-ray nanoprobes, coherence preservation, and astronomical physics.
Collapse
Affiliation(s)
- Hongchang Wang
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, OX11 0DE, UK.
| | - Simone Moriconi
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, OX11 0DE, UK
- Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, UK
| | - Kawal Sawhney
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, OX11 0DE, UK
| |
Collapse
|
6
|
Yamada J, Inoue I, Osaka T, Inoue T, Matsuyama S, Yamauchi K, Yabashi M. Hard X-ray nanoprobe scanner. IUCRJ 2021; 8:713-718. [PMID: 34584733 PMCID: PMC8420768 DOI: 10.1107/s2052252521007004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
X-ray scientists are continually striving to improve the quality of X-ray microscopy, due to the fact that the information obtained from X-ray microscopy of materials can be complementary to that obtained from optical and electron microscopes. In contrast to the ease with which one can deflect electron beams, the relative difficulty to deflect X-ray has constrained the development of scanning X-ray microscopes (SXMs) based on a scan of an X-ray small probe. This restriction has caused severe complications that hinder progress toward achieving ultimate resolution. Here, a simple and innovative method for constructing an SXM equipped with a nanoprobe scanner is proposed. The nanoprobe scanner combines X-ray prisms and advanced Kirkpatrick-Baez focusing mirrors. By rotating the prisms on the order of degrees, X-ray probe scanning with single-nanometre accuracy can be easily achieved. The validity of the concept was verified by acquiring an SXM image of a test pattern at a photon energy of 10 keV, where 50 nm line-and-space structures were resolved. This method is readily applicable to an SXM with a single-nanometre resolution and will assist effective utilization of increasing brightness of fourth-generation synchrotron radiation sources.
Collapse
Affiliation(s)
- Jumpei Yamada
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
- Division of Precision Engineering and Applied Physics, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Ichiro Inoue
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Taito Osaka
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | - Takato Inoue
- Division of Precision Engineering and Applied Physics, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Satoshi Matsuyama
- Division of Precision Engineering and Applied Physics, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
- Department of Materials Physics, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8603, Japan
| | - Kazuto Yamauchi
- Division of Precision Engineering and Applied Physics, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Makina Yabashi
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| |
Collapse
|