A method to retrieve small phase aberration from a single far-field image is proposed. It only needs to calibrate the inherent aberration of the imaging system once, and then the difference between a single measured image with aberration and the calibrated image with inherent aberration is got to retrieve the disturbed phase aberration by an approximate linear relationship. Computer simulations are employed to analyze the performance of this linear phase retrieval (LPR) wave-front sensor. The dynamic range of this method is discussed without noise to judge how small it is needed to satisfy the method. The results show that the proposed small phase retrieval method works well when the RMS phase error is less than 1.6 rad. The Linear Phase Retrieval wave-front sensor and the Hartmann-Shack wave-front sensor are compared on the same stochastic wave-front aberration. The influence of different calculation condition on the retrieval results is compared and analyzed. After analyzing the target resolution, it is thought that a reasonable target size is advantageous to the retrieval precision. At the same time, the LPR sensor can realize the alike precision measurement by using less detect cell, such as 8 pixelx8 pixel in our experiment. From the retrieval results of different orders, the error rate are less than 0.25 and it is comparatively accurate to retrieve pre-35 order aberrations.

Date Published: 31 December 2008
PDF: 7 pages
Proc. SPIE 7130, Fourth International Symposium on Precision Mechanical Measurements, 713017 (31 December 2008); doi: 10.1117/12.819581

Published in SPIE Proceedings Vol. 7130:
Fourth International Symposium on Precision Mechanical Measurements
Yetai Fei; Kuang-Chao Fan; Rongsheng Lu, Editor(s)