Alignment and calibration of the W.M. Keck Telescope segmented primary mirror.

摘要

We describe the camera, algorithms and software used to coalign (star stack) the 36 segments of the Keck Telescope primary. The camera and software also calibrate the sensors and actuators used for primary-mirror control and optimize the secondary-mirror position. Data resulting from these activities are used by the primary-mirror active control system to stabilize the primary segments and by the telescope drive and control system to adjust the secondary. The camera must collect data at various telescope temperatures and zenith angles. The data acquisition and analysis are automated to improve the accuracy and repeatability of the results and to reduce the demands on the operator. Under the operator's guidance, a DEC VAXstation II computer analyzes star images, issued commands to move the optical elements and telescope structure, acquires settings from the telescope and primary control systems and stores the measurement results in a database. 5 refs., 5 figs. (ERA citation 16:000910)