采用微分干涉显微镜、扫描电镜和聚焦离子束观察了偏振分光膜损伤的形貌，从损伤机理出发，研究了清洗对偏振分光膜损伤阈值的影响。结果表明：清洗能有效去除表面杂质，清洗质量越好，基板上的杂质尺寸越小，杂质密度也越小，相应的偏振分光膜S光的损伤阈值越高; 清洗能有效去除基板表面的纳米吸收中心，吸收性杂质分布密度越小，吸收峰越低，P光的损伤阈值越高。

Influence of cleaning process on laser-induced damage threshold of polarizers was studied. Nomarski microscope was used to inspect the cleaned substrate surface, scanning electron microscope combining with focus ion beam technologies was used to characterize the damage morphologies of polarizers. The initiators that trigger laser damage were correlated with cleaning process. Proper cleaning process resulted in fewer residual particles and nodules in the prepared polarizer, which increased the laser induced damage threshold (LIDT) for S-polarization. Moreover, the absorption peak of substrates became lower and sharper when surface contaminations were removed, which improved the LIDT of P-polarization. In conclusion, cleaning is an effective way to increase LIDTs of polarizers.