"Optical System-Specific Ground Calibration Equipment of Transport Spacecraft CCD Optical Imaging Sensor" developed by Testing Center of Xi’an Institute of Optics and Precision Mechanics (XIOPM), CAS, passed the appraisal hosted by Xi'an Branch of CAS, on May 11. Appraisal Committee heard the work report, technical report and evaluation report by the project team, reviewed the relevant information and formed the following opinions after careful questioning and discussion:
The project proposes the principle of distortion test in image plane of the optical system using star point method and successfully develops the testing equipment, which leads the new direction of distortion measurement technique. "Optical System-Specific Ground Calibration Equipment of Transport Spacecraft CCD Optical Imaging Sensor" uses microscope camera system as the receiver in image plane of optical system, applies optical zoom subdivision combined with image interpretation weighted centroid method for the star image position measurement, and meanwhile uses laser interferometry for high-precision measurement of microscopy system displacement in image plane of optical system making the measurement accuracy up to tens of nanometers. The device is of high-precision distortion measurement，combined with the design of optical system aberrations, distortion algorithm uses weighted least squares and the computation of theoretical image height uses standard turntable angle. The absolute accuracy of distortion measurement is better than ± 0.2 μm and the relative accuracy of distortion measurement is better than 0.002% in ± 10mm range of optical system image side line. Its use shows that the device has achieved a high-precision distortion test and can truly reflect the changes and distributions of the image plane distortion of the tested optical system. It has become optical system-specific ground calibration equipment of transport spacecraft CCD optical imaging sensor.
Appraisal Committee agreed that the research production of the project group is of key technological breakthrough with innovation and successful application. The research result has reached the international advanced level in general. The appraisal of scientific and technological achievements is passed. It is suggested to further expand the application areas promoting the development of optical testing technology.