Surface shape detection method and device of plane mirror

Abstract

The invention discloses a method and device for detecting the surface shape of a plane mirror. The method comprises: fixing a plane mirror to be inspected on a plane mirror inspection table, wherein the mirror surface of the plane mirror to be inspected is divided into a plurality of sub-apertures, and adjacent sub-apertures have overlapping regions; Using a standard spherical reflector and a spherical interferometer, the Ricky-Common method is used to measure the surface data of each sub-aperture respectively to obtain the surface data of each sub-aperture; splicing the surface data of each sub-aperture to obtain the Surface shape data for a plane mirror. The invention combines the Ricky-Common method with the sub-aperture method, divides the mirror surface of the large-diameter plane mirror to be inspected into a plurality of sub-apertures, utilizes the principle of the Ricky-Common method, and adopts a small-caliber standard spherical reflector for each sub-aperture. The surface shape data of the sub-apertures are measured, and the surface shape data of each sub-aperture are spliced ​​to obtain the overall surface shape data of the plane mirror to be tested. On the basis of not increasing the detection cost, the surface shape detection of the large-aperture plane mirror is realized.

Description

technical field [0001] The invention relates to plane mirror detection technology, more specifically, to a plane mirror surface shape detection method and device. Background technique [0002] In order to achieve a deeper and more detailed exploration of the universe, the aperture of the telescope is getting larger and larger, and the size of the plane mirror in its optical system is also getting larger and larger. Correspondingly, the requirements for the surface shape detection accuracy and the adjustment effect of large-diameter flat mirrors are getting higher and higher. At present, the root mean square detection error in the grinding stage of large-aperture flat mirrors needs to be better than the micron level, and the detection accuracy requirements in the polishing stage even reach the nanometer level. [0003] For small and medium caliber flat mirrors, the Foucault method or direct interferometry can be used to obtain the mirror surface shape. The Foucault method, ...

AI Technical Summary

Problems solved by technology

[0006] In view of this, the present invention provides a method and device for detecting the surface shape of a plane mirror, which can detect the surface shape data of a large-diameter plane mirror by using a small-diameter standard spherical mirror and a spherical interferometer, without increasing the detection cost. , which solves the difficulty in detecting the surface shape of large-diameter flat mirrors in the prior art

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