Initial test results from the Next Generation Space Telescope (NGST) wavefront sensing and control testbed (WCT)

摘要

This paper describes the results of a few of the initial series of tests being conducted with the first configuration of the Next Genration Space Telescope (NGST) Wavefront sensing and Control Testbed (WCT1). WCT1 is a 1:1, f/16.6 re-imaging system, incorporating two deformable mirrors (DM) located at pupil conjugate positions with 6 actuators/diameter (SM/DM) and 20 actuators/diameter (AO/DM). A CCD on a precision stage is used for obtaining deforcused images providing phase diversity for wavefront determination using phase retrieval. In a typical experiment, wavefront error (WFE) is injected into the optical path with the SM/DM and then corrected using he more densely actuated AO/DM. Wavefront analysis is provided via a phase retrieval agorithm, and control software is used to reshape the AO/DM and corect the wavefront. A summary of the results of some initial tests are presented.