A Wavefront Sensor Based on Adaptive Fitting

Abstract

The invention provides a wavefront sensor based on adaptive fitting. The wavefront sensor comprises a wavefront sensor, a wavefront fitting device and a wavefront recovery device. The wavefront sensor is used for receiving to-be-detected wavefront and carrying out segmentation and gathering processing on the to-be-detected wavefront so as to obtain a light spot array. The wavefront fitting device is used for carrying out recovery processing on the light spot array so as to obtain recovery wavefront and carrying out space iteration fitting processing on the recovery wavefront so as to obtain recovery wavefront compensation quantity reaching a stable value. The wavefront recovery device is used for carrying out recovery processing on the recovery wavefront compensation quantity which has reached the stable value so as to obtain recovery wavefront with high precision. The wavefront sensor carries out cycle measurement on error quantity subjected to compensation fitting under the effects of the wavefront fitting device, so when the cycle index is increased, error quantity fluctuations are reduced, the measurement precision is improved and high-precision measurement of the recovery wavefront is achieved.

Description

technical field [0001] The invention relates to the technical field of wavefront measurement, in particular to a wavefront sensor based on adaptive fitting. Background technique [0002] Wavefront measurement based on Hartmann wavefront detection technology has many advantages such as simple structure, convenient data processing, adjustable dynamic range, good real-time performance, etc., and has the characteristics of non-destructive and high precision, and has become a commonly used wavefront measurement. Devices are widely used in mirror surface shape detection, laser parameter diagnosis, flow field CT reconstruction, human eye aberration diagnosis, optical path collimation, etc. [0003] The Hartmann wavefront sensor in the prior art, as a wavefront testing instrument based on wavefront slope measurement, can divide the measured wavefront into several sampling units by the microlens array it includes, see figure 1 , these sampling units are collected at separate focal p...

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Problems solved by technology

On the one hand, considering the higher the spatial sampling frequency of the measured wavefront by the microlens array, the better the approximation of the fitting slope to the measured wavefront, and the closer the reconstructed wavefront is to the measured wavefront, the measurement accuracy However, in practical applications, it is impossible to increase the measurement accuracy of the Hartmann wavefront sensor by increasing the number of microlens arrays without limit, and the measurement error of the Hartmann wavefront sensor increases with the On the other hand, considering the noise of the CCD (Charge-coupled Device, charge-coupled device) camera, background noise and pixel sampling error, the CCD camera will cause Centroid measurement error, and for the measured wavefront with large aberration, the aberration will seriously affect the shape of the spot and the concentration of the spot energy, resulting in inaccurate measurement of the spot centroid

[0005] The inventor found in the research that the Hartmann wavefront sensor in the prior art has poor measurement accuracy due to the existence of spatial sampling errors and centroid measurement errors

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