Dr. Gregory R. Brady Profile

Dr. Gregory R. Brady

Principal Astronomical Optical Engineer

SPIE Involvement:

Author

Publications (16)

Proceedings Article | 23 August 2024 Presentation + Paper

Presentation + Paper

Empirical characterization of JWST wavefront error variations

Randal Telfer, Marcio Meléndez, Nicolas Flagey, Charles-Philippe Lajoie, Gregory Brady, Tracy Beck, Thomas Comeau, Bernard Kulp, Marshall Perrin, Matthew Lallo

Proceedings Volume 13092, 1309210 (2024) https://doi.org/10.1117/12.3020273

KEYWORDS: James Webb Space Telescope, Wavefronts, Observatories, Image segmentation, Wavefront errors, Phase retrieval, Vibration, Mirrors, Stars, Point spread functions

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SPIE Journal Paper | 15 November 2023 Open Access

Open Access

James Webb Space Telescope optical stability lessons learned for future great observatories

Lee Feinberg, Michael McElwain, Charles Bowers, John Johnston, Gary Mosier, Randy Kimble, Joshua Levi, Lightsey, Ball Aerospace, Boulder, Colorado, United States, J. Knight, Marcel Bluth, Alden Jurling, Marie Levine, D. Scott Acton, Charles Atkinson, Allison Barto, Matthew Bergkoetter, Gregory Brady, Larkin Carey, Lester Cohen, Laura Coyle, Bruce Dean, Michael Eisenhower, Nicolas Flagey, George Hartig, Keith Havey, Brian Hicks, Joseph Howard, Ritva Keski-Kuha, Charles-Philippe Lajoie, Matthew Lallo, Gary Matthews, Marcio Meléndez, Michael Menzel, Sang Park, Marshall Perrin, Laurent Pueyo, Lisbeth Quesnel, Paul Reynolds, Jane Rigby, Babak Saif, Christopher Stark, Randal Telfer, Scott Texter, Julie Van Campen, Begona Vila, Garrett West, Erin Wolf, Tony Whitman, Thomas Zielinski

JATIS, Vol. 10, Issue 01, 011204, (November 2023) https://doi.org/10.1117/12.10.1117/1.JATIS.10.1.011204

KEYWORDS: James Webb Space Telescope, Telescopes, Inspection, Online learning, Observatories, Thermal stability, Temperature metrology, Design, Cryogenics, Interfaces

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Proceedings Article | 27 August 2022 Presentation + Paper

Presentation + Paper

Phasing the Webb Telescope

D. Scott Acton, Scott Knight, Maria Carrasquilla, Nick Weiser, Michaela Masciarelli, Sarah Jurczyk, Greg Rapp, Julio Mueckay, Erin Wolf, Jess Murphy, Larkin Carey, Eric Coppock, Chanda Walker, Joel Runnels, Garrett West, Greg Wirth, Brian Hicks, Katie Melbourne, Michael Gordon, Bob Brown, Stefano Grimaldi, Derek Sabatke, Ray Wright, Laura Coyle, Taylor Chonis, Kevin Whiteaker, Marshall Perrin, Tom Comeau, Charles-Philippe Lajoie, George Hartig, Tracy Beck, Matt Lallo, Mike Regan, Randal Telfer, Marcio Meléndez, Greg Brady, Laurent Pueyo, Nicolas Flagey, Bernard Kulp, Ed Nelan, Kiera Brooks, Pierre Chayer, Shannon Osborne, Sherie Holfeltz, Tony Sohn, Tom Zielinski, Alden Jurling, Matt Bergkoetter, Chuck Bowers, Bruce Dean, Lee Feinberg, Ritva Keski-Kuha, Jeff Kirk, Michael McElwain, Joe Howard

Proceedings Volume 12180, 121800U (2022) https://doi.org/10.1117/12.2633474

KEYWORDS: Telescopes, James Webb Space Telescope, Mirrors, Wavefronts, Image processing, Actuators, Sensors, Phase retrieval

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Proceedings Article | 1 September 2021 Presentation + Paper

Presentation + Paper

Experimental validation of active control of low-order aberrations with a Zernike sensor through a Lyot coronagraph

Raphaël Pourcelot, Mamadou N'Diaye, Emiel Por, Marshall Perrin, Rémi Soummer, Iva Laginja, Ananya Sahoo, Marcel Carbillet, Greg Brady, Kjetil Dohlen, Matthew Maclay, Evelyn McChesney, James Noss, Pete Petrone, Laurent Pueyo, Arthur Vigan, Scott Will

Proceedings Volume 11823, 118231M (2021) https://doi.org/10.1117/12.2594609

KEYWORDS: Wavefronts, Coronagraphy, Turbulence, Wavefront sensors, Telescopes, Exoplanets

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Proceedings Article | 4 August 2021 Presentation

Presentation

High-contrast imager for complex aperture telescopes (HiCAT): 7. Dark zone demonstration with fully segmented aperture coronagraph

Rémi Soummer, Iva Laginja, Scott Will, Marshall Perrin, James Noss, Emiel Por, Susan Redmond, Raphaël Pourcelot, Ananya Sahoo, Peter Petrone, Keira Brooks, Laurent Pueyo, Bryony Nickson, Matt Maclay, Gregory Brady, Thomas Comeau, Julia Fowler, Kelsey Glazer, Rob Gontrum, John Hagopian, Theo Jolivet, Maggie Kautz, Lucie Leboulleux, Evelyn McChesney, Laurent Mugnier, Mamadou N'Diaye, Meiji Nguyen, Heather Olszewski, Leonid Pogorelyuk, Jaret Prothro, Jean-François Sauvage, Nathan Scott, Ron Shiri, Anand Sivaramakrishnan, Hari Subedi, Sam Weinstock, Yinzi Xin, Rebecca Zhang

Proceedings Volume 11823, 118230T (2021) https://doi.org/10.1117/12.2594684

KEYWORDS: Image segmentation, Coronagraphy, Telescopes, Imaging systems, Wavefront sensors, Wavefronts, Deformable mirrors, Ultraviolet telescopes, Ultraviolet radiation, UV optics

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Proceedings Article | 13 December 2020 Poster + Presentation + Paper

Poster + Presentation + Paper

Estimating low-order aberrations through a Lyot coronagraph with a Zernike wavefront sensor for exoplanet imaging

Raphaël Pourcelot, Mamadou N'Diaye, Greg Brady, Marcel Carbillet, Kjetil Dohlen, Julia Fowler, Iva Laginja, Matthew Maclay, James Noss, Marshall Perrin, Pete Petrone, Emiel Por, Jean-François Sauvage, Rémi Soummer, Arthur Vigan, Scott Will

Proceedings Volume 11443, 1144346 (2020) https://doi.org/10.1117/12.2562159

KEYWORDS: Space telescopes, Coronagraphy, Sensors, Telescopes, Stars, Image segmentation, Planets, Wavefronts, Mirrors, Calibration

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Proceedings Article | 9 September 2019 Presentation + Paper

Presentation + Paper

Phase-retrieval-based wavefront metrology for high-contrast coronography: 2. Reconstructions through a shaped pupil apodizer

Gregory Brady, Peter Petrone, Iva Laginja, Keira Brooks, Manxuan (Rebecca) Zhang, Mamadou N'Diaye, Christopher Moriarty, John Hagopian, Rémi Soummer

Proceedings Volume 11117, 1111712 (2019) https://doi.org/10.1117/12.2530482

KEYWORDS: Wavefronts, Wavefront metrology, Phase retrieval, Coronagraphy, Manufacturing, Exoplanets, Binary data, Imaging systems, Phase measurement, Deformable mirrors

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Proceedings Article | 9 September 2019 Presentation

Presentation

High-contrast imager for complex aperture telescopes (HiCAT): 6. Two deformable mirror wavefront control (Conference Presentation)

Rémi Soummer, Iva Laginja, Scott Will, Roser Juanola-Parramon, Peter Petrone, Greg Brady, James Noss, Marshall Perrin, Julia Fowler, Heather Kurtz, Kathryn St. Laurent, Kevin Fogarty, Evelyn McChesney, Nathan Scott, Keira Brooks, Thomas Comeau, Marc Ferrari, Rob Gontrum, John Hagopian, Emmanuel Hugot, Lucie Leboulleux, Johan Mazoyer, Laurent Mugnier, Mamadou N'Diaye, Laurent Pueyo, Jean-François Sauvage, Ron Shiri, Anand Sivaramakrishnan, Ana-Maria Valenzuela, Neil Zimmerman

Proceedings Volume 11117, 111171Y (2019) https://doi.org/10.1117/12.2530299

KEYWORDS: Telescopes, Deformable mirrors, Imaging systems, Wavefronts, Wavefront sensors, Coronagraphy, Cameras, Ultraviolet telescopes, Image segmentation, Space telescopes

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Proceedings Article | 21 August 2018 Presentation + Paper

Presentation + Paper

High-contrast imager for complex aperture telescopes (HiCAT): 5. first results with segmented-aperture coronagraph and wavefront control

Rémi Soummer, Gregory Brady, Keira Brooks, Thomas Comeau, Élodie Choquet, Tom Dillon, Sylvain Egron, Rob Gontrum, John Hagopian, Iva Laginja, Lucie Leboulleux, Marshall Perrin, Peter Petrone, Laurent Pueyo, Johan Mazoyer, Mamadou N'Diaye, A. J. Eldorado Riggs, Ron Shiri, Anand Sivaramakrishnan, Kathryn St. Laurent, Ana-Maria Valenzuela, Neil Zimmerman

Proceedings Volume 10698, 106981O (2018) https://doi.org/10.1117/12.2314110

KEYWORDS: Coronagraphy, Space telescopes, Wavefronts, Telescopes, Metrology, Phase retrieval, Carbon nanotubes

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Segmented telescopes are a possible approach to enable large-aperture space telescopes for the direct imaging and spectroscopy of habitable worlds. However, the increased complexity of their aperture geometry, due to the central obstruction, support structures and segment gaps, makes high-contrast imaging very challenging. The High-contrast imager for Complex Aperture Telescopes (HiCAT) testbed was designed to study and develop solutions for such telescope pupils using wavefront control and coronagraphic starlight suppression. The testbed design has the flexibility to enable studies with increasing complexity for telescope aperture geometries starting with off-axis telescopes, then on-axis telescopes with central obstruction and support structures - e.g. the Wide Field Infrared Survey Telescope (WFIRST) - up to on-axis segmented telescopes, including various concepts for a Large UV, Optical, IR telescope (LUVOIR). In the past year, HiCAT has made significant hardware and software updates in order to accelerate the development of the project. In addition to completely overhauling the software that runs the testbed, we have completed several hardware upgrades, including the second and third deformable mirror, and the first custom Apodized Pupil Lyot Coronagraph (APLC) optimized for the HiCAT aperture, which is similar to one of the possible geometries considered for LUVOIR. The testbed also includes several external metrology features for rapid replacement of parts, and in particular the ability to test multiple apodizers readily, an active tip-tilt control system to compensate for local vibration and air turbulence in the enclosure. On the software and operations side, the software infrastructure enables 24/7 automated experiments that include routine calibration tasks and high-contrast experiments. In this communication we present an overview and status update of the project, both on the hardware and software side, and describe the results obtained with APLC wavefront control.

Proceedings Article | 21 August 2018 Paper

Paper

High-contrast imager for complex aperture telescopes (HiCAT): 6. software control infrastructure and calibration

Christopher Moriarty, Keira Brooks, Rémi Soummer, Marshall Perrin, Thomas Comeau, Gregory Brady, Rob Gontrum, Peter Petrone

Proceedings Volume 10698, 1069853 (2018) https://doi.org/10.1117/12.2314058

KEYWORDS: Safety, Calibration, Interfaces, Space telescopes, Cameras, Telescopes, Control systems, Device simulation, Imaging systems

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Proceedings Article | 21 August 2018 Paper

Paper

James Webb Space Telescope optical simulation testbed V: wide-field phase retrieval assessment

Iva Laginja, Greg Brady, Rémi Soummer, Sylvain Egron, Christopher Moriarty, Charles-Philippe Lajoie, Aurélie Bonnefois, Vincent Michau, Élodie Choquet, Marc Ferrari, Lucie Leboulleux, Olivier Levecq, Mamadou N'Diaye, Marshall Perrin, Peter Petrone, Laurent Pueyo, Anand Sivaramakrishnan

Proceedings Volume 10698, 106983N (2018) https://doi.org/10.1117/12.2313892

KEYWORDS: Wavefronts, James Webb Space Telescope, Monochromatic aberrations, Point spread functions, Wavefront sensors, Mirrors, Cameras, Space telescopes, Telescopes, Phase retrieval

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Proceedings Article | 24 July 2018 Paper

Paper

Phase-retrieval-based wavefront metrology for high contrast coronagraphy

Gregory Brady, Christopher Moriarty, Peter Petrone, Iva Laginja, Keira Brooks, Tom Comeau, Lucie Leboulleux, Rémi Soummer

Proceedings Volume 10698, 106986I (2018) https://doi.org/10.1117/12.2314368

KEYWORDS: Optical metrology, In situ metrology, Wavefront sensors, Wavefront metrology, Wavefront reconstruction, Wavefronts, Phase retrieval, Coronagraphy, Calibration, Mirrors, Deformable mirrors, Telescopes

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Proceedings Article | 8 February 2012 Paper

Paper

Ultrafast diffractive optical micro-trap arrays for neutral atom quantum computing

S. Kemme, G. Brady, A. Ellis, J. Wendt, D. Peters, G. Biedermann, T. Carter, S. Samora, J. Isaacs, V. Ivanov, M. Saffman

Proceedings Volume 8249, 82490E (2012) https://doi.org/10.1117/12.910829

KEYWORDS: Diffractive optical elements, Chemical species, Optical arrays, Phase shifts, Optical tweezers, Optical components, Ultrafast phenomena, Luminescence, Wafer-level optics, Semiconducting wafers

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Proceedings Article | 9 September 2010 Paper

Paper

Miniaturized UV fluorescence collection optics integrated with ion trap chips

Gregory Brady, Shanalyn Kemme, A. Robert Ellis

Proceedings Volume 7652, 76522G (2010) https://doi.org/10.1117/12.871023

KEYWORDS: Ions, Integrated optics, Luminescence, Epoxies, Multimode fibers, Ceramics, Fiber couplers, Ultraviolet radiation, Gold, Visualization

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Proceedings Article | 18 June 2007 Paper

Paper

Effect of broadband illumination on reconstruction error of phase retrieval in optical metrology

Gregory Brady, James Fienup

Proceedings Volume 6617, 66170I (2007) https://doi.org/10.1117/12.726184

KEYWORDS: Phase retrieval, Data modeling, Optical metrology, Computer simulations, Wave propagation, Spherical lenses, Reconstruction algorithms, Inverse optics, Detection and tracking algorithms, Diffraction

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Proceedings Article | 2 May 2005 Paper

Paper

Phase retrieval as an optical metrology tool

Gregory Brady, James Fienup

Proceedings Volume 10315, 1031517 (2005) https://doi.org/10.1117/12.605914

KEYWORDS: Phase retrieval, Wavefronts, Optical metrology, Optical testing, Detector arrays, Aspheric lenses

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Showing 5 of 16 publications

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