Abstract

A high-speed interferometer has been designed and built to measure the dynamics of the James Webb Space Telescope primary mirror system currently under testing. This interferometer is capable of tracking large absolute motion (i.e., piston) of the mirror’s entire surface over orders of magnitudes of wavelengths displacement. Preliminary tests have shown it to be capable of measuring dynamic effects on the level of tens of picometers reliably. This paper reports the details of test setup to do so, the data system used to collect and process the data, and the algorithms to distill the dynamics motions detected. The results that were obtained are presented and followed by a discussion of the conclusions and potential applications of this measurement technique.

© 2017 Optical Society of America

Sub-picometer dynamic measurements of a diffuse surface

Babak Saif, Perry Greenfield, Michael North-Morris, Marcel Bluth, Lee Feinberg, J. C. Wyant, and Ritva Keski-Kuha
Appl. Opt. 58(12) 3156-3165 (2019)

Nanometer level characterization of the James Webb Space Telescope optomechanical systems using high-speed interferometry

Babak Saif, David Chaney, W. Scott Smith, Perry Greenfield, Warren Hack, Josh Bluth, Austin Van Otten, Marcel Bluth, James Sanders, Ritva Keski-Kuha, Lee Feinberg, Michael North-Morris, and James Millerd
Appl. Opt. 54(13) 4285-4298 (2015)

Measurement of large cryogenic structures using a spatially phase-shifted digital speckle pattern interferometer

Babak Saif, Marcel Bluth, Perry Greenfield, Warren Hack, Bente Hoffmann Eegholm, Peter Blake, Ritva Keski-Kuha, Lee Feinberg, and Jonathan W. Arenberg
Appl. Opt. 47(6) 737-745 (2008)

Tracking sub-nanometer thermal structural changes with speckle interferometry

Babak Saif, Perry Greenfield, Marcel Bluth, Lee Feinberg, J. C. Wyant, and Ritva Keski-Kuha
Appl. Opt. 59(22) G204-G208 (2020)

Calibration of spatially phase-shifted DSPI for measurement of large structures

Babak Saif, Bente Hoffmann Eegholm, Marcel Bluth, Perry Greenfield, Warren Hack, Peter Blake, Ritva Keski-Kuha, and Michael North-Morris
Appl. Opt. 46(23) 5622-5630 (2007)