Publication Date:
2019-07-13
Description:
Cryogenic testing of the James Webb Space Telescope (JWST) included center-of-curvature metrology of the 18-segment primary mirror (PM). The Center-of-Curvature Optical Assembly (COCOA) consisted of a multiple-wavelength interferometer, a reflective null, coarse and fine alignment systems, and two displacement measuring interferometer systems. The COCOA enabled alignment and phasing of the segments from millimeter-level errors down to the nanometer level. This paper describes the COCOA, the test setup, the testing performed, and the performance of the COCOA in aligning the PM segments and measuring the final PM wavefront error.
Keywords:
Optics
Type:
SPIE 10698-2
,
GSFC-E-DAA-TN57653
,
SPIE Astronomical Telescopes + Instrumentation; Jun 10, 2018 - Jun 15, 2018; Austin, TX; United States
Format:
application/pdf