Interferometric method using partial compensation lens to realize nno-spherical surface shape

Abstract

A interference measuring method of inspherical face form realized by using partial compensating lens belongs to electrooptical technical field, having no requirement that large aberration wave front of inspherical face form has to be compensated completely by compensating lens, but allowing residual wave difference not larger than fifty wavelengthes exists, changing traditional small wave difference interference measuring system into large wave difference by using digit Mohr phase shift phase shift method. The invention has the structure of compensating lens simplified. The difficulty of design, processing of which decreased and the measuring range of which extended; by using refraction principle, interference fringe is very clean because of no perturbance from other light created by holographic element, and which has little lose; the measuring accuracy is high and stability is good; it can be used to measure varies of rotational symmetric aspheric surface especially for aspheric surface with large relative aperture and convex inaspheric surface with large inaspheric ratio.

Description

Technical field [0001] The invention is an interferometric measurement method for realizing an aspheric surface shape by using a partially compensated lens, which belongs to the field of optoelectronics [0002] technology field. Background technique [0003] Measuring the surface shape of optical components by interferometry has the advantages of simplicity and high precision, and is currently widely used. Since the traditional interferometer can only measure wavelet aberration, the optical path of the interferometer is relatively simple when measuring simple wavelet aberration surfaces such as planes and spheres. The complex wave surface with large wave aberration generated is compensated as a wave surface with zero wave aberration. Compared with the standard surface in the interferometer, the irregular shape of the interference fringes represents the surface error of the aspheric surface, so that the measured aspheric surface can be directly measured. Surface error. Si...

AI Technical Summary

Problems solved by technology

The current solution to this problem is to use a holographic element with a spherical lens to compensate the large wave aberration produced by the aspheric surface. The holographic element is manufactured by a numerical control method, which can compensate almost any aspheric surface. However, due to the limitation of its diffraction principle, the transmitted light of the holographic element In addition to the useful measured wave surface, there are also zero-order and high-order sub-wave diffraction light, which makes the measured wave surface have greater stray light interference, interference fringes are not clean, and the quality is poor

In addition, because the diffraction efficiency is not high, and the light is diffracted twice, the loss of the reflected light wave is large

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