Mr. Bart Snijders Profile

Bart Snijders

Business Consultant Optics/Technical Sciences at TNO

SPIE Involvement:

Author

Proceedings Article | 6 October 2023 Poster

Manufacturing thin shell mirrors for adaptive optics

Bart Snijders, Nagihan Sezgin, Fred Kampheus, Stefan Kuiper, Arjo Bos, Jan De Vreugd, Wouter Jonker, Mark Chun, Philip Hinz, Bert Dekker, Douwe Jan IJlst, Bart Venrooy, Wendy Kleijn, Robin Buuren, Matias Kidron, Esperanza Vielba Salcedo, Glenn Zalen, Stefan Zaal, Constantin Meiners, Rik Horst

Proceedings Volume PC12677, PC126770N (2023) https://doi.org/10.1117/12.3005019

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Proceedings Article | 26 October 2016 Paper

High-grade, compact spectrometers for Earth observation from SmallSats

L. van der Wal, B. T. G. de Goeij, R. Jansen, J. A. J. Oosterling, B. Snijders

Proceedings Volume 10008, 1000806 (2016) https://doi.org/10.1117/12.2247299

KEYWORDS: Spectrometers, Manufacturing, Satellites, Optical design, Mirrors, Sensors, Spectral resolution, Spatial resolution, 3D printing, Ceramics

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The market for nano- and microsatellites is developing rapidly. There is a strong focus on 2D imaging of the Earth’s surface, with limited possibilities to obtain spectral information. More demanding applications, such as monitoring trace gases, aerosols or water quality still require advanced imaging instruments, which are large, heavy and expensive. In recent years TNO has investigated and developed different innovative designs to realize advanced spectrometers for space applications in a more compact and cost-effective manner. This offers multiple advantages: a compact instrument can be flown on a much smaller platform (nano- or microsatellite); a low-cost instrument opens up the possibility to fly multiple instruments in a satellite constellation, improving both global coverage and temporal sampling (e.g. to study diurnal processes); a constellation of low-cost instruments may provide added value to the larger scientific and operational satellite missions (e.g. the Copernicus Sentinel missions); and a small, lightweight spectrometer can also be mounted easily on a high-altitude UAV (offering high spatial resolution). Last but not least, a low-cost instrument may allow to break through the ‘cost spiral’: lower cost will allow to take more risk and thus progress more quickly. This may lead to a much faster development cycle than customary for current Earth Observation instruments. To explore the potential of a constellation of low-cost instruments a consortium of Dutch partners was formed, which currently consists of Airbus Defence and Space Netherlands, ISISpace, S and T and TNO. In this paper we will illustrate this new design approach by using the most advanced design of a hyperspectral imaging spectrometer (named ‘Spectrolite’) as an example. We will discuss the different design and manufacturing techniques that were used to realize this compact and low-cost design. Laboratory tests as well as the first preliminary results of airborne measurements with the Spectrolite breadboard will be presented and discussed. The design of Spectrolite offers the flexibility to tune its performance (spectral range, spectral resolution) to a specific application. Thus, based on the same basic system design, Spectrolite offers a range of applications to different clients. To illustrate this, we will present a mission concept to monitor NO2 concentrations over urban areas at high spatial resolution, based on a constellation of small satellites.

SPIE Journal Paper | 1 April 2007

Speckle effect on diffusers in space-based spectrometers

Hedser van Brug, Grégory Bazalgette Courrège-Lacoste, Jos Groote-Schaarsberg, Bart Snijders

OE, Vol. 46, Issue 04, 046201, (April 2007) https://doi.org/10.1117/12.10.1117/1.2722737

KEYWORDS: Diffusers, Spectrometers, Speckle, Speckle pattern, Sensors, Aluminum, Optical engineering, Light scattering, Prisms, Optical testing

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Proceedings Article | 22 August 2005 Paper

Spectral features due to on-board diffusers

Hedser van Brug, Gregory Bazalgette Courreges-Lacoste, Jos Groote Schaarsberg, Gerard Otter, Umberto Del Bello, Bart Snijders

Proceedings Volume 5882, 588202 (2005) https://doi.org/10.1117/12.616324

KEYWORDS: Diffusers, Speckle pattern, Speckle, Spectroscopy, Aluminum, Sensors, Polarization, Near infrared, Light sources, Satellites

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Proceedings Article | 26 October 2004 Paper

Speckles and their effects in spectrometers due to on-board diffusers

Hedser van Brug, Ramon Vink, Jos Groote Schaarsberg, Gregory Bazalgette Courreges-Lacoste, Bart Snijders

Proceedings Volume 5542, (2004) https://doi.org/10.1117/12.559596

KEYWORDS: Diffusers, Speckle pattern, Spectrometers, Sun, Speckle, Satellites, Light scattering, Sensors, Light sources, Scattering

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Proceedings Article | 25 October 2004 Paper

A large adaptive deformable membrane mirror with high actuator density

Roger Hamelinck, Nick Rosielle, Pieter Kappelhof, Bart Snijders, Maarten Steinbuch

Proceedings Volume 5490, (2004) https://doi.org/10.1117/12.551070

KEYWORDS: Actuators, Mirrors, Deformable mirrors, Wavefronts, Reflectivity, Prototyping, Beryllium, Solids, Telescopes, Adaptive optics

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Proceedings Article | 20 October 2004 Paper

Homothetic mapping as means to obtain a wide field of view: the Delft Testbed Interferometer

Hedser van Brug, Bastiaan Oostdijck, Bart Snijders, Casper van der Avoort, Pierre-Marie Gori

Proceedings Volume 5491, (2004) https://doi.org/10.1117/12.548802

KEYWORDS: Mirrors, Stars, Telescopes, Diffusion tensor imaging, Interferometers, Space telescopes, Xenon, CCD cameras, Observatories, Synthetic apertures

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Proceedings Article | 2 February 2004 Paper

Spectral features on reference diffusers: measurements and analysis

Gregory Bazalgette Courreges-Lacoste, Hedser van Brug, Jos Groote Schaarsberg, Bart Snijders, Rudolf Sprik, Ramon Vink, Dolf de Winter

Proceedings Volume 5234, (2004) https://doi.org/10.1117/12.510029

KEYWORDS: Diffusers, Speckle, Speckle pattern, Sensors, Spectrometers, Modulation, Polarization, Telescopic pixel displays, Calibration, Light sources

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Proceedings Article | 26 February 2003 Paper

Achromatic prism-based phaseshifter for nulling in the visible

H. Vink, Henk Bokhove, Bas Ouwerkerk, J. Kappelhof, Hedser van Brug, Bart Snijders, L. Vosteen

Proceedings Volume 4852, (2003) https://doi.org/10.1117/12.460741

KEYWORDS: Planets, Prisms, Nulling interferometry, Stars, Phase shifts, Sensors, Space telescopes, Polarization, Interferometers, Wavefronts

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Proceedings Article | 5 July 2000 Paper

GAIA testbench: monitoring the basic angle with micro-arcsecond accuracy

Bart Snijders, Pieter Kappelhof, Ben Braam, H. Vink, Peter Verhoeff, Bertrand Calvel, Frederic Safa

Proceedings Volume 4006, (2000) https://doi.org/10.1117/12.390172

KEYWORDS: Telescopes, Mirrors, Glasses, Space telescopes, Sensors, Metrology, Stars, Tolerancing, Optical alignment, Collimators

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Proceedings Article | 31 October 1996 Paper

Imaging spectrometer with a large field of view

Bart Snijders, Huib Visser

Proceedings Volume 2830, (1996) https://doi.org/10.1117/12.256126

KEYWORDS: Sensors, Polarization, Spectroscopy, Calibration, Spectral resolution, Ultraviolet radiation, Diffusers, Diffraction gratings, Mirrors, Signal to noise ratio

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