Unspecified Ian Lacey Profile

Ian Lacey

Scientific Engineering Associate at Lawrence Berkeley National Lab

Area of Expertise:

precision measurement , atomic spectroscopy , x-ray optics , metrology , data analysis

Publications (37)

Proceedings Article | 8 October 2024 Presentation + Paper

Binary pseudo-random array standards for calibration of 3D optical surface profilers used for metrology with significantly curved x-ray optics

K. Munechika, K. Yamada, S. Rochester, H. Barnard, W. Chao, I. Lacey, C. Pina-Hernandez, P. Takacs, V. Yashchuk

Proceedings Volume 13150, 1315007 (2024) https://doi.org/10.1117/12.3028493

KEYWORDS: Calibration, Fizeau interferometers, Distortion, Mirrors, Metrology, Optical surfaces, Design, Wavefront errors, X-ray optics, X-rays

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High-accuracy metrology is vitally important in manufacturing ultra-high-quality free-form mirrors designed to manipulate x-ray light with nanometer-scale wavelengths. The current capabilities and possibility for improvements in x-ray mirror manufacturing are limited by inherent imperfections of the integrated metrology tools. In the case of Fizeau interferometry, metrology tools are currently calibrated with super-polished flat test-standard/reference mirrors. This is acceptable for measuring slightly curved x-ray optics. However, for even moderately curved aspherical x-ray mirrors the flat-reference calibration is not sufficiently accurate and stitching Fizeau interferometer-based surface metrology is used to mitigate the problem. But still, the retrace and aberration errors, as well as the limited spatial resolution, described with the instrument transfer function (ITF), can be transferred into the optical surface topography of x-ray mirrors obtained in stitching metrology. For ITF calibration, we have developed an original technique, based on test standards structured as two-dimensional (2D) highly-randomized (HR) binary pseudo-random arrays (BPRAs). The technique employs the unique properties of the HR BPRA patterns in the spatial frequency domain., i.e. the inherent 2D power spectral density of the HR BPRA pattern has a deterministic white-noise-like character that allows direct determination of the ITF with uniform sensitivity over the entire spatial frequency range and field-of-view of an instrument. Here, we explore technological, metrological, and analytical aspects essential for calibration of the retrace and aberration errors of Fizeau interferometers using different types of tilted test samples, including a super-polished reference mirror for the re-trace calibration and the uniformly redundant array (URA) BPRA standards for the geometrical distortion (aberration) calibration. While the first method was previously demonstrated by researchers at DIAMOND Light Source, a method based on the URA BPRA is described and demonstrated here for the first time. We outline the design and fabrication process used in fabrication of URA BPRA test standards, and present the results of application of the URA BPRA standards demonstrating the high efficacy of our approach to geometrical distortion calibration of Fizeau interferometers. We also discuss the possible sources of unexpected peculiarities of the systematic errors, including an astigmatic character of the retrace error, observed with Fizeau interferometers at the Advanced Light Source X-Ray Optics Laboratory.

Proceedings Article | 4 October 2024 Presentation + Paper

Performance of plane wavefront Fizeau interferometers in power spectral density measurements with tilted plane optics

V. Yashchuk, K. Munechika, S. Rochester, P. Takacs, I. Lacey, K. Yamada

Proceedings Volume 13150, 1315006 (2024) https://doi.org/10.1117/12.3028336

KEYWORDS: Distortion, Fizeau interferometers, Windows, Spatial frequencies, Calibration, Optical surfaces, Wavefronts, Wavefront errors, Equipment, Metrology

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Proceedings Article | 30 September 2024 Paper

Binary pseudo-random array for calibration of interferometers with transmission spheres and cylinders

K. Munechika, S. Rochester, W. Chao, I. Lacey, C. Pina-Hernandez, K. Yamada, M. Biskach, P. Takacs, U. Griesmann, V. Yashchuk

Proceedings Volume 13135, 1313505 (2024) https://doi.org/10.1117/12.3028496

KEYWORDS: Computer generated holography, Fizeau interferometers, Spherical lenses, Fabrication, Microscopes, Calibration, Interferometry, Design, Reflection, Optical surfaces

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Proceedings Article | 12 October 2023 Presentation

Towards a new generation long trace profiler LTP-2020: design, motion control, and performance of a two-carriage gantry system

I. Lacey, K. Anderson, J. Dickert, D. English, B. Nelson, P. Takacs, V. Yashchuk

Proceedings Volume 12695, 1269504 (2023) https://doi.org/10.1117/12.2677786

KEYWORDS: Design and modelling, Control systems, Motion controllers, Sensors, X-ray optics, Optical surfaces, Optical sensors, Mirrors, Ceramics, X-rays

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Proceedings Article | 4 October 2023 Presentation + Paper

Binary pseudo-random array (BPRA) for inspection and calibration for cylindrical wavefront interferometry

K. Munechika, S. Rochester, W. Chao, I. Lacey, C. Pina-Hernandez, Kaito Yamada, M. Biskach, A. Numata, V. Yashchuk

Proceedings Volume 12677, 1267708 (2023) https://doi.org/10.1117/12.2677966

KEYWORDS: Metrology, Calibration, Optical surfaces, Microscopes, X-rays, Fabrication, Wavefronts, Mirror surfaces, Interferometry, Semiconducting wafers

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Proceedings Article | 4 October 2023 Presentation + Paper

Practical considerations in using a binary pseudorandom array for instrument transfer function calibration

P. Takacs, S. Rochester, I. Lacey, K. Munechika, U. Griesmann, V. Yashchuk

Proceedings Volume 12672, 126720K (2023) https://doi.org/10.1117/12.2677154

KEYWORDS: Microscopes, Modulation transfer functions, Aliasing, Cameras, Objectives, Calibration

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Proceedings Article | 3 October 2023 Presentation + Paper

Towards new generation long trace profiler LTP-2020: system design with different sensors in different operation modes

Valeriy Yashchuk, Kevan Anderson, Grant Cutler, Jeff Dickert, Damon English, Ralf Geckeler, Ian Lacey, Peter Takacs

Proceedings Volume 12695, 1269505 (2023) https://doi.org/10.1117/12.2677861

KEYWORDS: Sensors, Mirrors, Metrology, Diffraction gratings, Design and modelling, Autocollimators, X-ray optics, Mirror surfaces, X-rays, Optical surfaces

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Proceedings Article | 3 October 2023 Presentation + Paper

Towards a new generation long trace profiler LTP-2020: optical design of pencil beam interferometry sensor

P. Takacs, Ian Lacey, Valeriy Yashchuk

Proceedings Volume 12695, 1269502 (2023) https://doi.org/10.1117/12.2677418

KEYWORDS: Profilometers, Distortion, Wavefront errors, Reflection, Glasses, Cameras, Surface finishing, Sensors, Antireflective coatings, Design and modelling, Optical surfaces

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Proceedings Article | 4 October 2022 Presentation + Paper

The ALS interferometric microscope upgraded for measurements with large x-ray optics and optical assemblies

Ian Lacey, Kevan Anderson, Harold Barnard, Damon English, Wayne McKinney, Muhammad Saeed, Valeriy Yashchuk

Proceedings Volume 12240, 122400C (2022) https://doi.org/10.1117/12.2633103

KEYWORDS: Microscopes, X-ray optics, Interferometry, Software development, X-rays, Data processing, Mirrors, Sensors, Data acquisition, Metrology

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Proceedings Article | 4 October 2022 Presentation + Paper

Reliability investigation of the instrument transfer function calibration technique based on binary pseudo-random array standards

Valeriy Yashchuk, Keiko Munechika, Simon Rochester, Weilun Chao, Ian Lacey, Carlos Pina-Hernandez, Peter Takacs

Proceedings Volume 12240, 122400D (2022) https://doi.org/10.1117/12.2633476

KEYWORDS: Microscopes, Calibration, Zoom lenses, Interferometry, Spatial frequencies, Deconvolution, Reflectivity, Metrology, Objectives, Binary data

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Proceedings Article | 4 October 2022 Presentation + Paper

Towards super-resolution interference microscopy metrology of x-ray variable-line-spacing diffraction gratings: recent developments

Simon Rochester, Damon English, Ian Lacey, Keiko Munechika, Valeriy Yashchuk

Proceedings Volume 12240, 122400E (2022) https://doi.org/10.1117/12.2633637

KEYWORDS: Distortion, Microscopes, Metrology, Interferometry, Calibration, X-rays, Diffraction gratings, X-ray microscopy, X-ray diffraction, Super resolution

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Proceedings Article | 3 October 2022 Presentation + Paper

Calibration, modeling, parameterization, and verification of the instrument transfer function of an interferometric microscope

P. Takacs, S. Rochester, I. Lacey, K. Munechika, V. Yashchuk

Proceedings Volume 12223, 1222308 (2022) https://doi.org/10.1117/12.2633116

KEYWORDS: Modulation transfer functions, Microscopes, Objectives, Data modeling, Interferometry, Calibration, Spatial frequencies

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Proceedings Article | 3 October 2022 Presentation + Paper

Binary pseudo-random array standards for calibration of 3D optical surface profilers used for metrology with aspheric x-ray optics

Keiko Munechika, Weilun Chao, Scott Dhuey, Ian Lacey, Carlos Pina-Hernandez, Simon Rochester, Valeriy Yashchuk

Proceedings Volume 12223, 1222307 (2022) https://doi.org/10.1117/12.2633163

KEYWORDS: Calibration, Metrology, Distortion, Microscopes, X-ray optics, Standards development, X-rays, Mirrors, Interferometry, Spherical lenses

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High-accuracy surface metrology is vitally important in manufacturing ultra-high-quality free-form mirrors designed to manipulate x-ray light with nanometer-scale wavelengths. The current capabilities and possibility for improvements in x˗ray mirror manufacturing are limited by inherent imperfections of the integrated metrology tools. Metrology tools are currently calibrated with super-polished flat test-standard/reference mirrors. This is acceptable for fabrication of slightly curved x-ray optics. However, for even moderately curved aspherical x-ray mirrors the flat-reference calibration is not sufficiently accurate. In the case of micro-stitching interferometry developed for surface measurements with curved xray mirrors, the tool aberration errors are known to be transferred into the optical surface topography of x-ray mirrors. Our approach to improvement of the metrology is to thoroughly calibrate the measuring tool and apply the results of the calibration to gain the reliability of the metrology via calibration-based deconvolution of the measured data. Thus, we explore the application of a recently developed technique for calibrating the instrument’s transfer function (ITF) of 3D optical surface profilers to the metrology with significantly curved x-ray optics. The technique, based on test standards structured as two-dimensional (2D) binary pseudo-random arrays (BPRAs), employs the unique properties of the BPRA patterns in the spatial frequency domain. The inherent 2D power spectral density of the pattern has a deterministic whitenoise-like character that allows direct determination of the ITF with uniform sensitivity over the entire spatial frequency range and field-of-view of an instrument. The high efficacy of the technique has been previously demonstrated in application to metrology with flat and slightly curved optics. Here, we concentrate on development of an efficient fabrication process for production of highly randomized (HR) BPRA test standards on flat and 500-mm spherical optical substrates. We also compare and discuss the results of the ITF calibration of an interferometric microscope when using the HR BPRA standards on flat and curved substrates.

Proceedings Article | 3 October 2022 Presentation + Paper

Characterization of surface texture-measuring optical microscopes using a binary pseudo-random array standard

Ulf Griesmann, Keiko Munechika, T. Brian Renegar, X. Alan Zheng, Johannes Soons, Thomas Germer, Weilun Chao, Ian Lacey, Carlos Pina-Hernandez, Peter Takacs, Valeriy Yashchuk

Proceedings Volume 12223, 1222306 (2022) https://doi.org/10.1117/12.2633411

KEYWORDS: Microscopes, Spatial frequencies, Standards development, Confocal microscopy, Interferometry, Optical microscopes

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Proceedings Article | 5 August 2021 Presentation + Paper

Binary pseudo-random array test standard optimized for characterization of interferometric microscopes

Keiko Munechika, Stefano Cabrini, Weilun Chao, Ian Lacey, Carlos Pina-Hernandez, Simon Rochester, Valeriy Yashchuk

Proceedings Volume 11817, 1181704 (2021) https://doi.org/10.1117/12.2594995

KEYWORDS: Microscopes, Calibration, Metrology, Spatial frequencies, Interferometry, Binary data, Deconvolution, Point spread functions, Zoom lenses, X-ray optics

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