New Progress of CO2 Laser Processing Techniquesfor Fused Silica Optics

doi:10.3901/JME.2020.11.202

Abstract

Abstract: Fused silica optics is a typical hard and brittle material, which is inefficient in traditional mechanical processing for the difficult-to-process materials. And the mechanical weakening layer produced on processed surface seriously affects the service life of fused silica optics in the conditions of strong impact, high load, and high energy. Compared with traditional mechanical processing, the advantages of CO₂ laser processing technique are non-contact processing, high removal accuracy and high removal efficiency. Especially, the surface/subsurface cracks and scratches of fused silica optics processed by CO₂ laser do not exist. CO₂ laser processing technique has been widely used in processing of fused silica optics for these advantages. Therefore, this work reviews the development of CO₂ laser processing technique for fused silica optics from four aspects, i.e., the CO₂ laser processing theory of fused silica optics, the CO₂ laser processing technology for large-aperture optical elements, the CO₂ laser mitigating damages in local regions, and the CO₂ laser processing of surface microstructures. The respective capabilities and application status of CO₂ laser processing techniques for large-aperture or local region fused silica optics and surface microstructures have been analyzed. And the negative effects induced in CO₂ laser processing and the problems needing to be solved discussed in detail. This work is expected to provide reference for further application of CO₂ laser processing techniques for fused silica optics.

Key words: fused silica optics, laser processing, microstructure, surface modification, damage mitigation

CLC Number:

TN249

ZHAO Linjie, CHENG Jian, CHEN Mingjun, YUAN Xiaodong, LIAO Wei, YANG Hao, LIU Qi, WANG Haijun. New Progress of CO₂ Laser Processing Techniquesfor Fused Silica Optics[J]. Journal of Mechanical Engineering, 2020, 56(11): 202-218.

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New Progress of CO₂ Laser Processing Techniquesfor Fused Silica Optics

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