Design of a Phase Diversity Wavefront Sensor

The Phase Diversity Wavefront Sensing is to use focused and defocused images through fitting algorithms to recover phases, and thus the image of target. The required two images are formed on the focal plane and an off-focus plane, respectively. In this paper a new design of phase diversity wavefront sensor is presented to record the two images on a single CCD with crystal birefringence and ensure the equal intensities of the two images with high signal-to-noise ratios. The paper further analyzes the aberration of the design and simulates the performance the phase diversith wavefront sensor.