荧光显微立体成像测量光学元件亚表面损伤深度

Fluorescence Microscopic Stereo Imaging Method to Measure the Depth of Subsurface Damage of Optical Components

光学元件亚表面损伤直接影响光学系统激光损伤阈值,损伤深度是衡量亚表面损伤的关键参数之一,目前尚无成熟的快速定量测量方法。基于荧光显微立体成像技术提出一种损伤深度测量方法。首先,在光学元件加工过程中利用量子点对亚表面损伤进行标记;当激光束以一定角度入射光学元件表面时,标记量子点会受激产生荧光;通过荧光相机对损伤层纵向分布的荧光信号进行显微立体成像,根据成像原理和结构参数计算荧光分布深度,实现光学元件亚表面损伤深度的快速定量测量。通过光学胶和甩胶工艺制备了系列标准件,并开展对比验证测量实验,结果表明所提方法针对损伤深度55~75μm,测量相对误差小于8%。

Subsurface damage of optical components directly affects the laser damage threshold of optical systems,and the damage depth is one of the key parameters for measuring subsurface damage,for which there is no mature and rapid quantitative measurement method.A damage depth measurement method based on fluorescence microscopy stereoscopic imaging is proposed.First,during the processing of optical components,quantum dots are used to mark the subsurface damage;when the laser beam is incident on the surface of the optical component at a certain angle,the marked quantum dots are excited to generate fluorescence;the fluorescence signal of the longitudinal distribution of the damage layer is imaged microscopically by a fluorescence camera,and the fluorescence distribution depth is calculated according to the imaging principle and structural parameters to achieve rapid quantitative measurement of the subsurface damage depth of the optical component.A series of standard parts are prepared by optical glue and glue dumping process,and comparative verification measurement experiments are carried out,and the results show that the proposed method can measure the damage depth of 55~75μm with a relative error of less than 8%.