Dr. Stefan M. B. Bäumer Profile

Dr. Stefan M. B. Bäumer

Sr. Optical System Designer at TNO

SPIE Involvement:

Author | Editor

Area of Expertise:

Injection Molded optics , Optical Metrology , Optical System Design

Websites:

Company Website

Publications (22)

Proceedings Article | 19 November 2021 Presentation + Paper

Progress in aberration theory for freeform off-axis mirror systems

Jérôme Caron, Tiberiu Ceccotti, Stefan Bäumer

Proceedings Volume 12078, 120780G (2021) https://doi.org/10.1117/12.2603625

KEYWORDS: Monochromatic aberrations, Mirrors, Off axis mirrors, Aberration theory, Optical design

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Proceedings Article | 11 June 2021 Open Access

Progress in freeform mirror design for space applications

Jerome Caron, Stefan Bäumer

Proceedings Volume 11852, 118521S (2021) https://doi.org/10.1117/12.2599322

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Off-axis systems with freeform mirrors is a design approach of increasing importance for space instruments. While the off-axis reflective approach allows simple, versatile and obstruction free designs, the use of freeform surfaces allows to achieve better optical performance and/or compactness. In recent years, many such instruments have been designed and manufactured at TNO. Some important examples are the Tropomi (S5/precursor) and TSBOA (Sentinel-5) telescopes and several pushbroom spectrometers of the Spectrolite family. Despite the recognized potential of these systems, there is to our knowledge no available theory that allows to describe and predict the aberrations of plane symmetrical (off-axis) systems with freeform mirrors. In this context, an effort has been started 4 years ago at TNO to develop an approach that can describe and explore systematically off-axis freeform mirror systems with an arbitrary geometry. Since then the developed theory has been proven to be very useful in scanning the solution space for better starting designs, folding geometries and correction of lower aberrations in an early design phase. To circumvent difficulties linked to a wavefront formalism, generalized ray-tracing equations were derived, that include aberration terms up to 3rd order in X/Y object and pupil coordinates. These equations were recently published in two papers for the case of pure mirror systems [1,2]. The theory was also expanded to describe flat reflective gratings, opening a way to a complete description of reflective freeform spectrometers. In the present paper, after providing a high-level description and introduction to the aberration theory for freeform mirror systems, we will report some of its outcomes that have some practical relevance for space instruments. In particular: - two-mirror telescope designs for slit spectrometers (thus having a 1D field along the slit) that are inherently corrected for spatial smile will be presented. For these designs the slit projection in object space is exactly straight. - a new family of mirror spectrometers will be introduced that uses flat gratings and no collimator. In a collimator-less spectrometer, the aberrations induced by the grating under diverging light are corrected with freeform mirrors. The presented designs are entirely calculated from theory, with only optimization of the higher order freeform terms. A simpler architecture than traditional designs is obtained, with less optical surfaces. - finally we present a systematic classification of distortions in imaging slit spectrometers. The difference between distortions originating in the collimator and at the grating or in the imager is clarified and described mathematically. We discuss aberration-induced non-linear dispersion, as well as distortions from the keystone and smile families. The proposed classification also applies to catadioptric and refractive systems, the only requirement being to have a plane of symmetry.

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Proceedings Article | 3 September 2019 Paper

Setup of a confocal nanoscope in reflection using a super-oscillatory lens

Arvind Nagarajan, Marijn Siemons, L. Stoevelaar, Fabrizio Silvestri, Venu Gopal Achanta, Stefan M. Bäumer, Giampiero Gerini

Proceedings Volume 11089, 110892E (2019) https://doi.org/10.1117/12.2528717

KEYWORDS: Confocal microscopy, Polarization, Relays, Optical alignment, Alignment procedures, Point spread functions

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Proceedings Article | 14 May 2018 Paper

Color filter arrays based on dielectric metasurface elements

Jonas Berzins, Fabrizio Silvestri, Giampiero Gerini, Frank Setzpfandt, Thomas Pertsch, Stefan Bäumer

Proceedings Volume 10671, 106711F (2018) https://doi.org/10.1117/12.2307155

KEYWORDS: Optical filters, RGB color model, Silicon, Nanostructures, Dielectrics, Amorphous silicon, Refractive index, Cameras, Visible radiation

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Proceedings Article | 19 March 2018 Presentation + Paper

Diffuser concepts for in-situ wavefront measurements of EUV projection optics

Mark van de Kerkhof, Robbert Jan Voogd, Ad Schasfoort, Evert Westerhuis, Wouter Engelen, Manfred Dikkers, Yassin Chowdhury, Michael Kriese, Stefan Bäumer, Uwe Zeitner, Torsten Feigl

Proceedings Volume 10583, 105830S (2018) https://doi.org/10.1117/12.2297433

KEYWORDS: Diffusers, Extreme ultraviolet, Scanners, Scattering, Extreme ultraviolet lithography, Molybdenum

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Proceedings Article | 13 March 2018 Paper

Shot-noise limited throughput of soft x-ray ptychography for nanometrology applications

Wouter Koek, Bastiaan Florijn, Stefan Bäumer, Rik Kruidhof, Hamed Sadeghian

Proceedings Volume 10585, 1058533 (2018) https://doi.org/10.1117/12.2306488

KEYWORDS: Photons, Diffraction, Sensors, 3D metrology, Photomasks, Reflectivity, Semiconducting wafers, X-rays, Image resolution, 3D image processing

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Proceedings Article | 20 February 2017 Presentation + Paper

Robust design of microlenses arrays employing dielectric resonators metasurfaces

Fabrizio Silvestri, Giampiero Gerini, Stefan Bäumer

Proceedings Volume 10113, 101130M (2017) https://doi.org/10.1117/12.2250477

KEYWORDS: Resonators, Dielectrics, Optical design, Lenses, Particle swarm optimization, Computer aided design, Optics manufacturing, Wave propagation, Lens design, Geometrical optics

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Proceedings Article | 21 June 2015 Paper

Detection of fast flying nanoparticles by light scattering over a large volume

F. Pettazzi, S. Bäumer, J. van der Donck, A. Deutz

Proceedings Volume 9526, 95260O (2015) https://doi.org/10.1117/12.2186079

KEYWORDS: Particles, Sensors, Scattering, Light scattering, Laser scattering, Signal detection, Nanoparticles, Contamination, Mirrors, Interference (communication)

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Proceedings Article | 1 May 2014 Paper

A new design approach to innovative spectrometers. Case study: TROPOLITE

Jean-Baptiste Volatier, Stefan Baümer, Bob Kruizinga, Rob Vink

Proceedings Volume 9131, 91310L (2014) https://doi.org/10.1117/12.2051596

KEYWORDS: Optical design, Spectrometers, Optics manufacturing, Telescopes, Monochromatic aberrations, Mirrors, Imaging systems, Space telescopes, Mechanical engineering, Optical components

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Proceedings Article | 11 September 2008 Open Access

Integrating functions in polymer optical components

Stefan Bäumer, Maurice van der Beek

Proceedings Volume 7061, 706112 (2008) https://doi.org/10.1117/12.798246

KEYWORDS: Microfluidics, Metrology, Polymers, Optics manufacturing, Epoxies, Optical components, Integrated optics, Integration, Manufacturing, Temperature metrology

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Proceedings Article | 22 December 2003 Paper

Ultra-fast MTF Test for High-Volume production of CMOS Imaging Cameras

Michael Dahl, Josef Heinisch, Stefan Krey, Stefan Bäumer, Johan Lurquin, Linghua Chen

Proceedings Volume 5180, (2003) https://doi.org/10.1117/12.507928

KEYWORDS: Modulation transfer functions, Cameras, Ultrafast phenomena, Lenses, Imaging systems, Diffraction, Error analysis, Cell phones, Personal digital assistants, Objectives

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Proceedings Article | 3 November 2003 Paper

Integral optical system design of injection-molded optics

Stefan Baumer, Lena Shulepova, Jan Willemse, Kor Renkema

Proceedings Volume 5173, 517305 (2003) https://doi.org/10.1117/12.508593

KEYWORDS: Optical design, Lens design, Ray tracing, Solid modeling, Tolerancing, Optical engineering, Optical injection molds, Scanners, Digital video discs, Imaging systems

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Proceedings Article | 16 October 2003 Paper

Appearance characterization by a scatterometer employing a hemispherical screen

Sipke Wadman, Stefan Baumer

Proceedings Volume 5189, (2003) https://doi.org/10.1117/12.503560

KEYWORDS: Cameras, Reflection, Visualization, Scattering, Mirrors, Optical testing, Sensors, Optical spheres, Calibration, Reflectivity

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Proceedings Article | 11 November 1999 Paper

Optical figure testing by scanning deflectometry

Willem van Amstel, Stefan Baumer, Jef Horijon

Proceedings Volume 3782, (1999) https://doi.org/10.1117/12.369201

KEYWORDS: Mirrors, Deflectometry, Optical components, Optical testing, Interferometers, Calibration, Optics manufacturing, Sensors, Actinium, Interferometry

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Proceedings Article | 17 September 1999 Paper

Metrology of injection-molded optical components with multiple optical functions

Wim Timmers, Stefan Baumer, Ben van Iersel, Arno Ras, Rien de Schipper, Gert Verkade

Proceedings Volume 3778, (1999) https://doi.org/10.1117/12.363744

KEYWORDS: Mirrors, Calibration, Metrology, Optical components, Beam splitters, Interferometers, Tolerancing, Wavefronts, Endoscopes, Integrated optics

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Proceedings Article | 6 September 1999 Paper

Minideflectometer for measuring optical finish quality

Willem van Amstel, Stefan Baumer, Fred Couweleers

Proceedings Volume 3739, (1999) https://doi.org/10.1117/12.360167

KEYWORDS: Polishing, Surface finishing, Head, Mirrors, Magnetism, Spatial frequencies, Deflectometry, Optics manufacturing, Scattering, Multi-element lenses

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Proceedings Article | 6 September 1999 Paper

Optical figure testing by scanning deflectometry

Willem van Amstel, Stefan Baumer, Jef Horijon

Proceedings Volume 3739, (1999) https://doi.org/10.1117/12.360155

KEYWORDS: Mirrors, Deflectometry, Optical components, Optical testing, Interferometers, Calibration, Actinium, Sensors, Optics manufacturing, Interferometry

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Proceedings Article | 6 September 1999 Paper

SLIOS: a contribution to standard procedures in stray light measurements

Stefan Baumer, Angela Duparre, Thomas Herrmann, Uwe Schumann, Kees Smorenburg, Volker Kirschner, Lars Mattsson, Teresita Quinteros, Richard Berglind, Stefan Schippel

Proceedings Volume 3739, (1999) https://doi.org/10.1117/12.360173

KEYWORDS: Bidirectional reflectance transmission function, Standards development, Optical testing, Scatter measurement, Mirrors, Stray light, Light scattering, Scattering, Calibration, Data modeling

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Proceedings Article | 27 August 1999 Paper

Temperature-compensated plastic lens for visible light

Stefan Baumer, Wim Timmers, Mark Krichever, Vladimir Gurevich

Proceedings Volume 3737, (1999) https://doi.org/10.1117/12.360028

KEYWORDS: Diffraction, Temperature metrology, Manufacturing, Lens design, Scanners, Semiconductor lasers, Glasses, Mechanical engineering, Aspheric lenses, Wavefront aberrations

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Proceedings Article | 27 August 1999 Paper

Design of a compact 3D laser scanner

Mark Geusen, Willem van Amstel, Stefan Baumer, Jef Horijon

Proceedings Volume 3737, (1999) https://doi.org/10.1117/12.360015

KEYWORDS: Mirrors, Laser scanners, Confocal microscopy, 3D scanning, Sensors, Scanners, Inspection, Relays, Optical scanning systems, Signal detection

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