Dr. Denis G. Dufour Profile

Dr. Denis G. Dufour

Research Scientist at INO

SPIE Involvement:

Author

Publications (18)

Proceedings Article | 20 November 2024 Paper

GHG measurements using an imaging FTS on a stratospheric balloon: a tech demo for the Arctic observing mission

Shen-En Qian, Stephane Routhier, Tongxi Wu, Denis Dufour, Stéphane Lantagne, Frédéric Grandmont, Doug Degenstein, Alexis Bourassa, Adam Bourassa, Daniel Zawada, Nicholas Lloyd, Paul Loewen, Jeff Langille, Ray Nassar, Chris Sioris, Joseph Mendonca

Proceedings Volume 13193, 1319309 (2024) https://doi.org/10.1117/12.3030957

KEYWORDS: Equipment, Balloons, Calibration, Fourier transforms, Prototyping, Interferometers, Data acquisition, Cameras, Spectroscopy

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Proceedings Article | 18 September 2018 Paper

A low resource imaging radiometer for nanosatellite based fire diagnosis

Linh Ngo Phong, Denis Dufour, Joshua Johnston, Claude Chevalier, Patrice Côté, Bruno Fisette, Min Wang, François Châteauneuf

Proceedings Volume 10765, 1076502 (2018) https://doi.org/10.1117/12.2320661

KEYWORDS: Sensors, Telescopes, Mid-IR, Long wavelength infrared, Cameras, Transmittance, Radiometry, Microbolometers

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Proceedings Article | 14 May 2018 Paper

Customized packaged bolometers in niche applications at INO

Bruno Fisette, Francis Généreux, David Béland, Patrice Topart, Mathieu Tremblay, Yan Desroches, Marc Terroux, Linda Marchese, Christian Proulx, Francis Picard, Denis Dufour, Alain Bergeron, François Châteauneuf, Christine Alain

Proceedings Volume 10656, 106560H (2018) https://doi.org/10.1117/12.2303513

KEYWORDS: Sensors, Bolometers, Staring arrays, Microbolometers, Packaging, Terahertz radiation, Radiometry, Reflectivity

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Proceedings Article | 8 May 2018 Presentation + Paper

Subwavelength imaging challenges in the infrared and THz wavebands

Alain Bergeron, Linda Marchese, Marc Terroux, Michel Doucet, Nathalie Blanchard, Denis Dufour, Loïc Le Noc, Martin Otis, Michel Jacob, François Duchesne, Marc Girard, Luc Mercier, Lucie Gagnon, Bruno Fisette, Mathieu Tremblay, Bruno Tremblay, Martin Briand, Hélène Spisser, Pascal Bourqui

Proceedings Volume 10639, 1063909 (2018) https://doi.org/10.1117/12.2306294

KEYWORDS: Imaging systems, Terahertz radiation, Infrared imaging, Infrared radiation, Sensors, Detector arrays, Image resolution, Optical design, Indium oxide, Cameras

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Proceedings Article | 22 February 2018 Presentation + Paper

Portable LWIR hyperspectral imager based on MEMS Fabry-Perot interferometer and broadband microbolometric detector array

David Béland, Hélène Spisser, Denis Dufour, Loïc Le Noc, Francis Picard, Patrice Topart

Proceedings Volume 10545, 105450S (2018) https://doi.org/10.1117/12.2291751

KEYWORDS: Cameras, Hyperspectral imaging, Imaging systems, Infrared imaging, Staring arrays, Microelectromechanical systems, Interferometers, Sensors, Long wavelength infrared, Spectrometers

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Proceedings Article | 3 May 2017 Paper

Novel vacuum packaged 384 x 288 broadband bolometer FPA with enhanced absorption in the 3-14 µm wavelength range

Bruno Fisette, Mathieu Tremblay, Hassane Oulachgar, Francis Généreux, David Béland, Patrick Beaupré, Christian Julien, David Gay, Sébastien Deshaies, Marc Terroux, Bruno Tremblay, Denis Dufour, Christine Alain

Proceedings Volume 10177, 101771R (2017) https://doi.org/10.1117/12.2255747

KEYWORDS: Bolometers, Microbolometers, Packaging, Absorption, Sensors, Infrared radiation, Thin films, Indium oxide, Modulation transfer functions

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Proceedings Article | 20 February 2017 Paper

Uncooled midwave infrared sensors for spaceborne assessment of fire characteristics

Linh Ngo Phong, Francis Picard, Jacques-Edmond Paultre, Francis Généreux, Denis Dufour, François Châteauneuf

Proceedings Volume 10116, 101160N (2017) https://doi.org/10.1117/12.2250968

KEYWORDS: Mid-IR, Bolometers, Infrared sensors, Remote sensing, Microbolometers, Resistance, Semiconducting wafers, Wheatstone bridges, Readout integrated circuits

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Spaceborne assessment of fire characteristics relies on radiance measurement of fire pixels and non-fire pixels mainly in the midwave infrared (MWIR). Because ambient temperature non-fire pixels have low thermal emission in this spectral range, it remains a challenge to retrieve fire characteristics with the desired accuracy. This paper reports on uncooled microbolometers specially designed with low noise equivalent power (NEP) to enable fire diagnosis at MWIR wavelengths. Each microbolometer forming a 512x3 format array includes a Wheatstone bridge of one active, one blind, and two thermally shunted pixels followed by its own signal chain. Design analyses suggest the conditions for achieving the best NEP performance are: (i) the active, blind, and one shunt pixel have equal electrical resistances while the other shunt pixel has a larger resistance; (ii) the temperature difference between the active pixel and heat sink corresponds to about one-third the heat sink temperature; and (iii) the active and blind pixels have low thermal mass and conductance. Hardwired devices having different structural layouts were prepared for the validation of physical parameters and performance so that the suitable designs could be identified. After this, focal planes of 512x3 microbolometers were fabricated on readout electronics to allow further performance evaluation and development of staggered 1017x3 format arrays for a planned mission. The active pixel designs on the fabricated arrays exhibit a MWIR absorptance as high as 0.83 through implementation of a Salisbury screen absorber, a thermal conductance of ~ 67 nW/K, and a response time shorter than 10 ms. Their responsivities are found to be in good agreement with predictions of the design analysis. The effectiveness of an Al shield platform erected above the blind pixel was investigated, showing that certain designs are capable of attenuating the incident power by up to 24 times. Under optimal operating conditions an NEP of ~ 64 pW was derived from measurements in the spectral range of 3.4-4.2 um, which was corroborated by the probing results obtained on the on-wafer focal plane arrays. When using these arrays with an F/1 telescope to retrieve scenes of 400 K from low Earth orbits, a noise equivalent temperature difference of ~ 320 mK can be achieved.

Proceedings Article | 25 May 2016 Paper

Reflection imaging in the millimeter-wave range using a video-rate terahertz camera

Linda Marchese, Marc Terroux, Michel Doucet, Nathalie Blanchard, Ovidiu Pancrati, Denis Dufour, Alain Bergeron

Proceedings Volume 9836, 98362S (2016) https://doi.org/10.1117/12.2225178

KEYWORDS: Cameras, Terahertz radiation, Staring arrays, Millimeter wave imaging, Imaging systems, Sensors, Digital cameras, Fiber optic gyroscopes, Visualization, Humidity

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Proceedings Article | 7 October 2014 Paper

Software thermal imager simulator

Loic Le Noc, Ovidiu Pancrati, Michel Doucet, Denis Dufour, Benoit Debaque, Simon Turbide, Francois Berthiaume, Louis Saint-Laurent, Linda Marchese, Martin Bolduc, Alain Bergeron

Proceedings Volume 9249, 92490B (2014) https://doi.org/10.1117/12.2066841

KEYWORDS: Sensors, Imaging systems, Atmospheric modeling, Modulation transfer functions, Atmospheric optics, Point spread functions, Atmospheric particles, Computer simulations, Video, Fiber optic gyroscopes

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Proceedings Article | 4 June 2014 Paper

Case study of concealed weapons detection at stand-off distances using a compact, large field-of-view THz camera

Linda Marchese, Marc Terroux, Denis Dufour, Martin Bolduc, Claude Chevalier, Francis Généreux, Hubert Jerominek, Alain Bergeron

Proceedings Volume 9083, 90832G (2014) https://doi.org/10.1117/12.2050635

KEYWORDS: Terahertz radiation, Cameras, Weapons, Thin film coatings, Infrared radiation, Imaging systems, Image transmission, X-rays, Image resolution, Staring arrays

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Proceedings Article | 7 March 2014 Paper

Wafer-level radiometric performance testing of uncooled microbolometer arrays

Denis Dufour, Patrice Topart, Bruno Tremblay, Christian Julien, Louis Martin, Carl Vachon

Proceedings Volume 8975, 89750C (2014) https://doi.org/10.1117/12.2040201

KEYWORDS: Staring arrays, Microbolometers, Semiconducting wafers, Indium oxide, Black bodies, Readout integrated circuits, Cameras, Imaging systems, Germanium, Wafer testing

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Proceedings Article | 4 June 2013 Paper

Diffraction limit investigation with sub-wavelength pixels

A. Bergeron, M. Terroux, L. Marchese, D. Dufour, L. Le Noc, C. Chevalier

Proceedings Volume 8725, 872527 (2013) https://doi.org/10.1117/12.2015627

KEYWORDS: Terahertz radiation, Cameras, Staring arrays, Imaging systems, Diffraction, Image transmission, Infrared imaging, Infrared radiation, Visible radiation, Image resolution

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Proceedings Article | 7 May 2012 Paper

Introducing sub-wavelength pixel THz camera for the understanding of close pixel-to-wavelength imaging challenges

A. Bergeron, L. Marchese, M. Bolduc, M. Terroux, D. Dufour, E. Savard, B. Tremblay, H. Oulachgar, M. Doucet, L. Le Noc, C. Alain, H. Jerominek

Proceedings Volume 8373, 83732A (2012) https://doi.org/10.1117/12.920481

KEYWORDS: Terahertz radiation, Cameras, Image quality, Sensors, Indium oxide, Modulation transfer functions, Infrared imaging, Infrared radiation, Image resolution, Imaging systems

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Proceedings Article | 13 October 2011 Paper

Resolution capability comparison of infrared and terahertz imagers

Alain Bergeron, Linda Marchese, Éric Savard, Loïc LeNoc, Martin Bolduc, Marc Terroux, Denis Dufour, Denis Tang, François Châteauneuf, Hubert Jerominek

Proceedings Volume 8188, 81880I (2011) https://doi.org/10.1117/12.898937

KEYWORDS: Infrared imaging, Infrared radiation, Modulation transfer functions, Terahertz radiation, Sensors, Image resolution, Cameras, Infrared detectors, Imaging systems, Image quality

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Proceedings Article | 21 May 2011 Paper

Towards very high-resolution infrared camera core

Loïc Le Noc, Denis Dufour, Marc Terroux, Bruno Tremblay, Julie Lambert, Luc Mercier, Martin Morissette, Carl Vachon, Denis Tang, Alain Bergeron

Proceedings Volume 8012, 80123P (2011) https://doi.org/10.1117/12.887391

KEYWORDS: Sensors, Modulation transfer functions, Cameras, Lenses, Indium oxide, Long wavelength infrared, Imaging systems, Prototyping, Spatial resolution, Image processing

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