Wave front recovery method for curvature wave front sensor

Abstract

The invention provides a wave front recovery method for a curvature wave front sensor, which includes the steps as follows: firstly, recording defocusing light spots I1(r) (on the inner side of the focus point) and I2(r) (on the outer side of the focus point) of a curvature wave front sensor at symmetrical positions on the two sides of a focal plane, and generating a curvature wave front sensor signal S0(r) and taking the signal as the initial input; secondly, estimating the wave front aberration phi(r) as per the curvature wave front sensor signal; thirdly, obtaining the aberration phi est(r) through adding the boundary condition limitation; fourthly, estimating the curvature wave front sensor signal S(r) through the phi est; fifthly, obtaining the revised curvature wave front sensor signal S est(r) combined with the pupil limitation; sixthly, calculating the defocusing light spot Iest, 1(r) as per the phi est(r) and through the combination with the defocusing amount 1; and seventhly, comparing the similarity of the I1(r) and the I est,1(r) to obtain the iteration stopping criteria, and outputting if the condition is met, otherwise going to step 2 and continuing iterating. The method utilizes the repeated iteration between the wave aberration and the curvature wave front sensor signal to reduce the theory error of the curvature wave front sensor, thereby obtaining a high-precision wave front measurement result.

Description

technical field [0001] The invention relates to the technical field of curvature wavefront sensor detection, in particular to a wavefront reconstruction method for improving the accuracy of the curvature wavefront sensor, which can reduce the loss of detection accuracy caused by the principle error of the curvature wavefront sensor. Background technique [0002] The curvature wavefront sensor was proposed by F.Roddier in 1987. As a relatively new wavefront detection technology, compared with the Shack-Hartmann wavefront sensor, radial grating transverse shear interferometer, etc. to measure the wavefront The method of slope restoration of wavefront aberration is different. It obtains the curvature of the wavefront by measuring the light intensity distribution on the out-of-focus plane, and then obtains the wavefront aberration distribution. [0003] The schematic diagram of the curvature wavefront sensor is shown in the attached picture figure 1 shown. In the figure, P1 an...

AI Technical Summary

Problems solved by technology

The biggest advantage of this method is that the amount of calculation is small and the speed is fast; the disadvantage is that the accuracy is poor, because only the spot information is used once and there are too many constraints (take (2) as the boundary condition)

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