Optical component surface defect screening device and screening method

Abstract

The invention relates to a surface defect screening device for an optical element and a screening method thereof. The device comprises a pulse laser source, an electric displacement table, a focusing lens, a PIN tube, a data collection card, a computer and a fixing piece, wherein the optical element to be tested is fixed on the electric displacement table through the fixing piece, the pulse laser source irradiates the optical element, then is reflected, the focusing lens and the PIN tube are sequentially arranged in the direction of a reflected light beam, and the PIN tube is positioned on an image plane of the focusing lens; and signals output by the PIN tube are collected via the data collection card and sent to the computer, and the output end of the computer is connected with the control end of the electric displacement table. According to the device and the method, provided by the invention, positions, basic sizes and other information of surface defects of the optical element can be recorded in real time, and the device and the method have the characteristics of simplicity, real-time property, automation and reliability.

Description

technical field [0001] The invention relates to an optical element surface defect, in particular to an optical element surface defect screening device and screening method. Background technique [0002] Surface defects of optical components include pits and scratches formed during component processing, impurities inside the surface coating, small lenses formed by inhomogeneity of refractive index inside optical components, and laser damage formed during the use of optical components. Some damage points will grow under laser irradiation, and the optical field modulation caused by the damage points will destroy the optical components in the subsequent optical path. [0003] The existing defect detection technology mainly utilizes various effects produced by the interaction between laser and optical components. The common ones are plasma flash method, astigmatism method, photothermal method and so on. [0004] The plasma flash method refers to that when the pulsed laser acts ...

AI Technical Summary

Problems solved by technology

The image subtraction method requires high system stability, otherwise virtual images will appear after the difference, resulting in misjudgment

In addition, due to the small photosensitive area of ​​the area array CCD, the detection of large-aperture optical elements needs to be carried out in blocks, and one optical element needs to collect multiple images, which takes a long time

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