目的 提出一种光学玻璃机械加工亚表面损伤深度的检测方法，给光学玻璃超精密抛光的加工深度提供参考依据。方法 首先通过实验分析K9玻璃研磨试样在化学蚀刻过程中亚表面裂纹的结构变化，采用探针式粗糙度仪检测化学蚀刻表面的裂纹深度，并探讨探针半径和化学蚀刻时间对裂纹深度测量结果的影响，建立以蚀刻表面峰谷粗糙度(PV)表征亚表面裂纹深度的测量条件。然后利用激光共聚焦显微镜检测化学蚀刻表面PV粗糙度，确定光学玻璃的亚表面裂纹深度。最后采用截面抛光法直接检测光学玻璃的亚表面裂纹深度，验证上述两种检测方法的可靠性。结果 以蚀刻表面PV粗糙度表征亚表面裂纹深度的测量条件为，测量介质须在蚀刻表面裂纹开始融合之前有效探测至裂纹底部。针对W18和W40磨粒研磨的K9玻璃试样，采用激光共聚焦显微镜检测蚀刻表面PV粗糙度方法测得的两种试样裂纹深度为12.82 μm和20.45 μm，直接测量方法的测量结果为12.50 μm和19.34 μm。两种方法测量结果的偏差分别为2.56%和5.74%，一致性较好。结论 基于化学蚀刻和激光共聚焦显微镜检测光学玻璃亚表面损伤深度的方法不受表面裂纹宽度限制，满足以蚀刻表面PV粗糙度表征亚表面损伤深度的测量条件，且对试样损伤较小，提高了光学玻璃亚表面损伤深度的测量效率和结果可靠性。

The work aims to propose a detection method of the mechanically processed subsurface damage depth of optical glass to provide reference for the ultra-precision polishing depth of optical glass. Firstly, the microstructural evolution of the subsurface crack of K9 glass during HF/NH4F etching was studied, the crack depth of etching surface was detected by probe roughness tester, and the influence of probe radius and etching time on subsurface crack depth was discussed. Therefore, the measuring requirements for characterizing subsurface crack depth based on surface peak-to-valley (PV) roughness curve were established. Then, the PV roughness of etching surface was measured by laser scan confocal microscopy to determine the subsurface crack depth of optical glass. Finally, the subsurface damage depth was measured directly by cross-sectional polishing method to verify the reliability of the above two detection methods. The measurement condition of characterizing the depth of subsurface cracks by PV roughness of etching surface was that the measuring medium must effectively detect the bottom of cracks before the cracks on etching surface began to fuse. For the K9 glass samples lapped with W18 and W40 abrasives, subsurface crack depth of these two samples detected by the method based on etching process and laser scan confocal microscopy was 12.82 μm and 20.45 μm, while the results detected by the cross-sectional method were 12.50 μm and 19.34 μm. The deviation between these two methods was 2.56% and 5.74%, respectively. The obtained results were in concordance in the both used methods. Furthermore, the methods based on chemical etching process and laser scan confocal microscopy are not limited by the width of surface crack, and also meet the requirements for characterizing subsurface crack depth with PV roughness curve, with less damage on samples, which improves measurement efficiency and result reliability of the subsurface damage depth of optical glass.