Dr. Hong Tang Profile

Dr. Hong Tang

at Jet Propulsion Lab

SPIE Involvement:

Author

Publications (46)

Proceedings Article | 5 October 2023 Presentation + Paper

The decadal survey testbed two: a technology development facility for future exo-Earth observatories

Matthew Noyes, Alex Walter, Greg Allan, Garreth Ruane, Eduardo Bendek, Phillip Poon, Camilo Meija Prada, A.J. El Dorado Riggs, Hong Tang, Seth Meeker

Proceedings Volume 12680, 1268017 (2023) https://doi.org/10.1117/12.2676452

KEYWORDS: Coronagraphy, Cameras, Wavefronts, Wavefront sensors, Point spread functions, Electric fields, Vacuum, Thermal stability, Mirrors

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Due to the reporting from the Astro2020: Decadal Survey for Astronomy and Astrophysics, the direct imaging of Earth-like exoplanets has become a leading priority for research and development in astrophysics. In response to this survey, NASA has selected the Habitable Worlds Observatory (HWO) as its next astrophysics flagship mission. However, the current state-of-the-art coronagraph technology is not sufficient to achieve the required contrast (approximately 10⁻¹⁰) with HWO’s proposed configuration. Improving the technology readiness level of coronagraphs for HWO will require extensive research and development. To increase its capacity to support this objective and to provide the community with a new resource to perform versatile coronagraph technology development, NASA’s High Contrast Imaging Testbed (HCIT) facility at the Jet Propulsion Laboratory (JPL) has commissioned the Decadal Survey Testbed 2 (DST2), a state-of-the-art vacuum coronagraph testbed. It’s commissioned architecture incorporates a 2K-actuator Boston Micromachines deformable mirror and a traditional Lyot coronagraph and features a flexible design capable of accommodating different coronagraph technologies including tip/tilt mirrors, segmented apertures, reflective pupils, disturbance injection, wavefront sensing and control, and the integration of additional sources or telescope simulators with minimal reconfiguration. DST2 has repeatably achieved 1 × 10⁻⁹ monochromatic raw contrast, and 3.3 × 10⁻⁹ raw contrast in a 10% bandwidth centered at 550nm in a 180 degree dark hole from 3λ/D to 9λ/D. Additionally, DST2 uses new 20-bit DM electronics capable of a 650 femtometer DM actuator resolution which meets future requirements for HWO. As of August 2023, DST2 has begun operations to meet scientific milestones set by the principal investigators of NASA Strategic Astrophysics Technologies awards. Parallel to these priorities, work to determine contrast limitations will be performed.

SPIE Journal Paper | 24 May 2023 Open Access

Random vibration testing of microelectromechanical deformable mirrors for space-based high-contrast imaging

Axel Potier, Camilo Mejia Prada, Garreth Ruane, Hong Tang, Wesley Baxter, Duncan Liu, A. J. Eldorado Riggs, Phillip K. Poon, Eduardo Bendek, Nick Siegler, Mary Soria, Mark Hetzel, Charlie Lam, Paul Bierden

JATIS, Vol. 9, Issue 02, 029001, (May 2023) https://doi.org/10.1117/12.10.1117/1.JATIS.9.2.029001

KEYWORDS: Actuators, Microelectromechanical systems, Vibration, Deformation, Coronagraphy, Connectors, Inspection, Exoplanets, Deformable mirrors, Equipment

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Proceedings Article | 29 August 2022 Poster

Update on the survivability of high-actuator-count MEMS deformable mirror to rocket launch.

Axel Potier, Garreth Ruane, Camilo Mejia Prada, Wesley Baxter, Duncan Liu, Hong Tang, A.J. Eldorado Riggs, Phillip Poon, Eduardo Bendek, Nick Siegler, Mary Soria, Mark Hetzel, Charlie Lam, Paul Bierden

Proceedings Volume 12180, 121805S (2022) https://doi.org/10.1117/12.2629915

KEYWORDS: Microelectromechanical systems, Deformable mirrors, Rockets, Exoplanets, Coronagraphy, Wavefronts, Reliability, Manufacturing, Astrophysics, Astronomy

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Proceedings Article | 1 September 2021 Presentation + Paper

Environmental testing of high-actuator-count MEMS deformable mirrors for space-based applications

Camilo M. Prada, Duncan Liu, Garreth Ruane, Hong Tang, Axel Potier, Paul Bierden, Charlie Lam

Proceedings Volume 11823, 118230M (2021) https://doi.org/10.1117/12.2594263

KEYWORDS: Actuators, Microelectromechanical systems, Deformable mirrors, Oxides, Mirrors, Coronagraphy, Silicon, Etching, Manufacturing, Semiconducting wafers

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Proceedings Article | 1 September 2021 Presentation + Paper

The Twin decadal survey testbeds in the high contrast imaging testbed facility at NASA’s jet propulsion laboratory

Seth Meeker, Matthew Noyes, Hong Tang, Garreth Ruane, Camilo Mejia Prada, Eduardo Bendek, Wesley Baxter, Brendan Crill, A. J. Eldorado Riggs, Phillip Poon, Nicholas Siegler

Proceedings Volume 11823, 118230Y (2021) https://doi.org/10.1117/12.2594668

KEYWORDS: Coronagraphy, Wavefronts, Exoplanets, Data modeling, Microelectromechanical systems, Wavefront sensors

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Proceedings Article | 12 January 2021 Presentation + Paper

Roman space telescope coronagraph: engineering design and operating concept

Ilya Poberezhskiy, Thomas Luchik, Feng Zhao, Margaret Frerking, Scott Basinger, Eric Cady, M. Mark Colavita, Brandon Creager, Nanaz Fathpour, Renaud Goullioud, Tyler Groff, Patrick Morrissey, Joshua Kempenaar, Brian Kern, Timothy Koch, John Krist, Fai Mok, David Muliere, Bijan Nemati, A.J. Riggs, Byoung-Joon Seo, Fang Shi, Belinda Shreckengost, John Steeves, Hong Tang

Proceedings Volume 11443, 114431V (2021) https://doi.org/10.1117/12.2563480

KEYWORDS: Infrared telescopes, James Webb Space Telescope, Telescopes, Coronagraphy, Infrared radiation, Instrumentation engineering, Optical instrument design, Wavefronts, Imaging spectroscopy, Infrared imaging

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Proceedings Article | 15 December 2020 Presentation + Paper

The Nancy Grace Roman Space Telescope Coronagraph Instrument (CGI) technology demonstration

N. Jeremy Kasdin, Vanessa Bailey, Bertrand Mennesson, Robert Zellem, Marie Ygouf, Jason Rhodes, Thomas Luchik, Feng Zhao, A. J. Eldorado Riggs, Byoung-Joon Seo, John Krist, Brian Kern, Hong Tang, Bijan Nemati, Tyler Groff, Neil Zimmerman, Bruce Macintosh, Margaret Turnbull, John Debes, Ewan Douglas, Roxana Lupu

Proceedings Volume 11443, 114431U (2020) https://doi.org/10.1117/12.2562997

KEYWORDS: Coronagraphy, Imaging spectroscopy, Planets, Infrared telescopes, James Webb Space Telescope, Imaging systems, Wavefronts, Algorithm development, Jupiter, Infrared radiation

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Proceedings Article | 13 December 2020 Poster + Paper

Prediction and evaluation of the image of the WFIRST coronagraph pupil at the shaped-pupil mask

David Marx, Brian Kern, John Krist, Bala Balasubramanian, A. J. Eldorado Riggs, Byoung-Joon Seo, Eric Cady, Hong Tang, Camilo Prada, Garreth Ruane, Fang Shi, Charley Noecker, Blake Crowther

Proceedings Volume 11443, 1144339 (2020) https://doi.org/10.1117/12.2562629

KEYWORDS: Coronagraphy, Image analysis, Telescopes, Optical instrument design, Optimization (mathematics), Wavefronts, Deformable mirrors, Modulation, Tolerancing, Performance modeling

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Proceedings Article | 16 September 2019 Presentation + Paper

Testbed demonstration of high-contrast coronagraph imaging in search for Earth-like exoplanets

Byoung-Joon Seo, Keith Patterson, Kunjithapatham Balasubramanian, Brendan Crill, Talso Chui, Daniel Echeverri, Brian Kern, David Marx, Dwight Moody, Camilo Mejia Prada, Garreth Ruane, Fang Shi, John Shaw, Nick Siegler, Hong Tang, John Trauger, Daniel Wilson, Robert Zimmer

Proceedings Volume 11117, 111171V (2019) https://doi.org/10.1117/12.2530033

KEYWORDS: Coronagraphy, Exoplanets, Space telescopes, James Webb Space Telescope, Infrared telescopes, Visible radiation, Aerospace engineering, Space operations, Telescopes, Near infrared

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Proceedings Article | 16 September 2019 Presentation + Paper

Design description and commissioning performance of a stable coronagraph technology development testbed for direct imaging of Earth-like exoplanets

Keith Patterson, Byoung-Joon Seo, Kunjithapatham Balasubramanian, Talso Chui, Brendan Crill, John Gill, Brian Kern, Ray Lam, David Marx, Dwight Moody, Camilo Mejia Prada, Garreth Ruane, Jordan Rupp, John Shaw, Fang Shi, Nicholas Siegler, Hong Tang, John Trauger, Victor White, Daniel Wilson, Karl Yee, Robert Zimmer

Proceedings Volume 11117, 111171U (2019) https://doi.org/10.1117/12.2530401

KEYWORDS: Exoplanets, Coronagraphy, Deformable mirrors, Visible radiation, Turbulence, Convection, Composites, Vibration isolation, Electronics, Wavefront sensors

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Proceedings Article | 16 September 2019 Presentation + Paper

The WFIRST coronagraph instrument phase B optical design

Hong Tang, Michael Rodgers, Brandon Creager, John Krist, James McGuire, Keith Patterson, Mayer Rud, Fang Shi, Feng Zhao

Proceedings Volume 11117, 111170C (2019) https://doi.org/10.1117/12.2530506

KEYWORDS: Coronagraphy, Optical design, Mirrors, Deformable mirrors, Exoplanets, Stars, Astronomical imaging, Optical fabrication, Optical alignment, Polarization

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Proceedings Article | 30 July 2018 Presentation + Paper

WFIRST low order wavefront sensing and control dynamic testbed performance under the flight like photon flux

Fang Shi, Byoung-Joon Seo, Eric Cady, Brian Kern, Raymond Lam, David Marx, Keith Patterson, Camilo Mejia Prada, John Shaw, Chris Shelton, Joel Shields, Hong Tang, Tuan Truong

Proceedings Volume 10698, 106982O (2018) https://doi.org/10.1117/12.2312746

KEYWORDS: Sensors, Coronagraphy, Wavefronts, Cameras, Stars, Wavefront sensors, Line of sight stabilization, Mirrors, Telescopes, Actuators

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To maintain the required performance for the WFIRST Coronagraph Instrument (CGI) in a realistic space environment, a Low Order Wavefront Sensing and Control (LOWFS/C) subsystem is necessary. The WFIRST CGI LOWFS/C subsystem will use the Zernike wavefront sensor, which has a phase-shifting disk combined with the coronagraph’s focal plane mask, to sense the low-order wavefront drift and line-of-sight (LoS) error using the rejected starlight. The dynamic tests on JPL’s Occulting Mask Coronagraph (OMC) Testbed have demonstrated that LOWFS/C can maintain coronagraph contrast to better than 10^-8 in presence of WFIRST-like line of sight and low order wavefront disturbances in both Shaped Pupil Coronagraph (SPC) and Hybrid Lyot Coronagraph (HLC) modes. However, the previous dynamic tests have been done using a bright source with photon flux equivalent to stellar magnitude of MV = -3.5. The LOWFS/C technology development on the OMC testbed has since then concentrated in evaluating and improving the LOWFS/C performance under the realistic photon flux that is equivalent to WFIRST Coronagraph target stars. Our recent testbed tests have demonstrated that the LOWFS/C can work cohesively with the stellar light suppression wavefront control, which brings broad band coronagraph contrast from ~1x10^-6 to 6x10^-9, while LOWF/C is simultaneously suppressing the WFIRST like LoS and low order wavefront drift disturbances on a source that photon flux is equivalent to a MV = 2 star. This lab demonstration mimics the CGI initial dark hole establish process on a bright reference star. We have also demonstrated on the testbed that LOWFS/C can maintain the coronagraph contrast by suppressing the WFIRST like line-of-sight disturbances on a fainter MV = 5 star. This mimics scenario of CGI science target observations. In this paper we will present the recent dynamic testbed performance results of LOWFS/C LoS loops and low order wavefront error correction loop on the flight like photon flux.

Proceedings Article | 16 July 2018 Presentation + Paper

WFIRST coronagraph flight performance modeling

John Krist, Robert Effinger, Brian Kern, Milan Mandic, James McGuire, Dwight Moody, Patrick Morrissey, Ilya Poberezhskiy, A. J. Riggs, Navtej Saini, Erkin Sidick, Hong Tang, John Trauger

Proceedings Volume 10698, 106982K (2018) https://doi.org/10.1117/12.2310043

KEYWORDS: Coronagraphy, Thermal modeling

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Proceedings Article | 10 July 2018 Presentation

The wide field infrared survey telescope (WFIRST) observatory: design formulation (phase-A) overview (Conference Presentation)

Thomas Casey, Nerses Armani, Wes Alexander, Lisa Bartusek, Carl Blaurock, David Braun, Alexander Carra, David Content, Yves Conturie, Christine Cottingham, Richard Demers, Michael Dipirro, Robert Effinger, Robert Egerman, Frank Forkl, Guangjun Gao, John Gygax, John Hagopian, Timothy Hahm, John Hawk, Gurnie Hobbs, Clifton Jackson, Alden Jurling, Brian Kern, Jeffrey Kruk, Xiaoyi Li, Kuo-chia Liu, Catherine Marx, Marzouk Marzouk, Carson McDonald, Seke Godo, Mark Melton, James Mondello, M. Charley Noecker, Bert Pasquale, Hume Peabody, Ilya Poberezhskiy, Cory Powell, Giulio Rosanova, John Ruffa, Jeffrey Smith, Hong Tang, Christopher Tolman, Arthur Whipple, Timothy Wilson, Melissa Vess, Perry Voyer

Proceedings Volume 10698, 106982C (2018) https://doi.org/10.1117/12.2313748

KEYWORDS: Infrared telescopes, Space telescopes, Observatories, Telescopes, Infrared radiation, Optical instrument design, Infrared imaging, Exoplanets, Imaging spectroscopy, Coronagraphy

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Proceedings Article | 1 September 2017 Paper

Shaped pupil coronagraphy for WFIRST: high-contrast broadband testbed demonstration

Eric Cady, Kunjithapatham Balasubramanian, Jessica Gersh-Range, Jeremy Kasdin, Brian Kern, Raymond Lam, Camilo Mejia Prada, Dwight Moody, Keith Patterson, Ilya Poberezhskiy, A. J. Eldorado Riggs, Byoung-Joon Seo, Fang Shi, Hong Tang, John Trauger, Hanying Zhou, Neil Zimmerman

Proceedings Volume 10400, 104000E (2017) https://doi.org/10.1117/12.2272834

KEYWORDS: Wavefronts, Coronagraphy, Exoplanets, Wavefront sensors, Performance modeling, Systems modeling, Control systems

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Proceedings Article | 1 September 2017 Presentation + Paper

WFIRST coronagraph optical modeling

John Krist, A. J. Riggs, James McGuire, Hong Tang, Nikta Amiri, Gary Gutt, Luis Marchen, David Marx, Bijan Nemati, Navtej Saini, Erkin Sidick, Hanying Zhou

Proceedings Volume 10400, 1040004 (2017) https://doi.org/10.1117/12.2274792

KEYWORDS: Performance modeling, Systems modeling, Exoplanets, Spectrographs, Mirrors, Telescopes, Wavefront sensors, Polarization, Tolerancing, MATLAB

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Proceedings Article | 1 September 2017 Presentation + Paper

Dynamic testbed demonstration of WFIRST coronagraph low order wavefront sensing and control (LOWFS/C)

Fang Shi, Eric Cady, Byoung-Joon Seo, Xin An, Kunjithapatham Balasubramanian, Brian Kern, Raymond Lam, David Marx, Dwight Moody, Camilo Mejia Prada, Keith Patterson, Ilya Poberezhskiy, Joel Shields, Erkin Sidick, Hong Tang, John Trauger, Tuan Truong, Victor White, Daniel Wilson, Hanying Zhou

Proceedings Volume 10400, 104000D (2017) https://doi.org/10.1117/12.2274887

KEYWORDS: Wavefront sensors, Wavefronts, Mirrors, Deformable mirrors, Environmental sensing, Phase shifting, Optical telescopes, Optical fabrication, Device simulation, Space telescopes

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Proceedings Article | 1 September 2017 Presentation + Paper

The WFIRST coronagraph instrument optical design update

Hong Tang, Richard Demers, John Krist, James McGuire, Mayer Rud, Feng Zhao

Proceedings Volume 10400, 1040003 (2017) https://doi.org/10.1117/12.2274549

KEYWORDS: Optical design, Wavefronts, Exoplanets, Coronagraphy, Stars, Channel projecting optics, Iterated function systems, Polarization, Optical coatings, Stray light analysis

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Proceedings Article | 22 August 2017 Presentation + Paper

Ground to on-orbit alignment study of the WFIRST wide-field channel and resulting changes in the telescope architecture

John Hagopian, Nerses Armani, Lisa Bartusek, Tom Casey, Dave Content, Yves Conturie, Guangjun Gao, Alden Jurling, Cathy Marx, Joe Marzouk, Bert Pasquale, J. Scott Smith, Hong Tang, Arthur Whipple

Proceedings Volume 10377, 103770E (2017) https://doi.org/10.1117/12.2280333

KEYWORDS: Space telescopes, Telescopes, Mirrors, Infrared telescopes, Space operations, Optical telescopes, Coronagraphy, Monte Carlo methods, Infrared astronomy, Infrared radiation

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Proceedings Article | 29 July 2016 Paper

Low order wavefront sensing and control for WFIRST coronagraph

Fang Shi, Kunjithapatham Balasubramanian, Randall Bartos, Randall Hein, Raymond Lam, Milan Mandic, Douglas Moore, James Moore, Keith Patterson, Ilya Poberezhskiy, Joel Shields, Erkin Sidick, Hong Tang, Tuan Truong, James Wallace, Xu Wang, Daniel Wilson

Proceedings Volume 9904, 990418 (2016) https://doi.org/10.1117/12.2234226

KEYWORDS: Wavefront sensors, Space telescopes, Wavefronts, Mirrors, Telescopes, Coronagraphy, Sensors, Cameras, Monochromatic aberrations, Device simulation

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Proceedings Article | 29 July 2016 Paper

PISCES: an integral field spectrograph technology demonstration for the WFIRST coronagraph

Michael McElwain, Avi Mandell, Qian Gong, Jorge Llop-Sayson, Timothy Brandt, Victor Chambers, Bryan Grammer, Bradford Greeley, George Hilton, Marshall Perrin, Karl Stapelfeldt, Richard Demers, Hong Tang, Eric Cady

Proceedings Volume 9904, 99041A (2016) https://doi.org/10.1117/12.2231671

KEYWORDS: Spectrographs, Iterated function systems, Imaging spectroscopy, Sensors, Coronagraphy, Point spread functions, Relays, Mirrors, Prisms, Collimators

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SPIE Journal Paper | 15 March 2016

Low-order wavefront sensing and control for WFIRST-AFTA coronagraph

Fang Shi, Kunjithapatham Balasubramanian, Randall Hein, Raymond Lam, Douglas Moore, James Moore, Keith Patterson, Ilya Poberezhskiy, Joel Shields, Erkin Sidick, Hong Tang, Tuan Truong, J. Kent Wallace, Xu Wang, Daniel Wilson

JATIS, Vol. 2, Issue 01, 011021, (March 2016) https://doi.org/10.1117/12.10.1117/1.JATIS.2.1.011021

KEYWORDS: Coronagraphy, Wavefront sensors, Wavefronts, Sensors, Telescopes, Actuators, Space telescopes, Control systems, Cameras, Mirrors

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SPIE Journal Paper | 28 January 2016

Phase-induced amplitude apodization complex mask coronagraph mask fabrication, characterization, and modeling for WFIRST-AFTA

Brian Kern, Olivier Guyon, Ruslan Belikov, Daniel Wilson, Richard Muller, Erkin Sidick, Bala Balasubramanian, John Krist, Ilya Poberezhskiy, Hong Tang

JATIS, Vol. 2, Issue 01, 011014, (January 2016) https://doi.org/10.1117/12.10.1117/1.JATIS.2.1.011014

KEYWORDS: Planets, Coronagraphy, Wavefronts, Apodization, Scanning electron microscopy, Mask making, Atomic force microscopy, Reflectivity, Mirrors, Polymethylmethacrylate

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