A New Method Based on Morphologic Filter and Ant Colony Algorithm to Enhance Centroid Detection Accuracy of Shack-Hartmann Wavefront Sensor

摘要

Shack-Hartmann wavefront sensor (SHWFS) is widely used in adaptive optics systems. Its centroid detecting error is one of the main error sources in adaptive optical systems. There are many factors affecting the detecting accuracy such as photon shot noise, readout noise, background level of CCD camera and number of detecting pixels. It is very effective to enhance the centroid accuracy by setting the threshold for the images of the SHWFS. But in daytime, the sky background is strong and changes very fast. The threshold cannot be chosen automatically either. In this paper, a new method based on the morphologic filter and ant colony algorithm is proposed to improve the SHWFS centroid detecting accuracy. The principle of the morphologic filter and the ant colony algorithm is introduced and the simulation results are also presented. The results show the proposed method can enhance SHWFS centroid accuracy very well.