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NASA NTRS · 20150008486

The JWST/NIRCam Coronagraph Flight Occulters

Krist, John E.·Balasubramanian, Kunjithapatham·Muller, Richard E.·Shaklan, Stuart B.·Kelly, Douglas M.·Wilson, Daniel W.·Beichman, Charles A.·Serabyn, Eugene·Mao, Yalan·Echternach, Pierre M.·Trauger, John T.·Liewer, Kurt M.
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Abstract

The NIRCam instrument on the James Webb Space Telescope will have a Lyot coronagraph for high contrast imaging of extrasolar planets and circumstellar disks at lambda = 2 - 5 micrometers. Half-tone patterns are used to create graded-transmission image plane masks. These are generated using electron beam lithography and reactive ion etching of a metal layer on an antireflection coated sapphire substrate. We report here on the manufacture and evaluation of the flight occulters.

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Krist, John E., Balasubramanian, Kunjithapatham, Muller, Richard E., Shaklan, Stuart B., Kelly, Douglas M., Wilson, Daniel W., Beichman, Charles A., Serabyn, Eugene, Mao, Yalan, Echternach, Pierre M., Trauger, John T., Liewer, Kurt M.. 2010-06-27. The JWST/NIRCam Coronagraph Flight Occulters. https://ntrs.nasa.gov/citations/20150008486

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