Detecting device and method for tri-plane absolute measurement of optical surface

Abstract

The invention provides a detecting device and method for tri-plane absolute measurement of an optical surface. The light emitted by a laser generates reference light after penetrating through a spatial filter, a spectroscope, a collimation optical component, and an upper plane of a first clamping support; planes of the first clamping support and a second clamping support generate interference; and interference light passes through the spectroscope and a condenser after returning through a light path, and is collected by a charge-coupled device (CCD) detector. A phase shifter is used for generating phase shift, and a rotary table is used for controlling the rotation of the plane on the second clamping support. Detection results in different dimension directions of the planes on the first clamping support and the second clamping support can be generated by using a computer to control the insertion of an image inversion component, and the absolute surface of planes can be worked out through the rotation of the plane on the second clamping support. According to the detecting device and the method for the tri-plane absolute measurement of the optical surface, the problem of solution of odd-odd functions is solved on the basis of the existing odd-even function method of tri-plane measurement, and measurement frequency needed by the solution of high-frequency component is reduced simultaneously.

Description

technical field [0001] The invention belongs to the technical field of optical detection, and relates to a detection device and method for three-plane absolute measurement of optical surface shape. Background technique [0002] High-precision interferometric surface measurements are becoming more and more important, not only in the traditional field of optical manufacturing, but also in new fields such as the surface of optical discs or the surface of semiconductor crystals. There are more and more requirements for the detection accuracy of surface shape peak-valley PV in the sub-nanometer range. With the rapid development of modern industry and science and technology, especially the continuous improvement of modern large-scale integrated circuit technology, the requirements for system precision are increasing day by day. In lithography systems, shorter and shorter wavelengths require us to use higher precision lithography objectives. Before that, we need higher precision ...

AI Technical Summary

Problems solved by technology

The traditional technology mainly rotates the first plane to be measured

The first plane to be measured is rotated by 180°, 90°, and 45°, among which the 180° rotation can be used to obtain the odd-even and even-odd items, and the 90° and 45° rotations are mainly used to approximate and obtain the odd-odd components, and if it is necessary to obtain more If there are too many odd and odd components, it is necessary to increase the angle rotation, and the traditional method cannot completely find the odd and odd components

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