Detection of the laser-damage onset in optical coatings by the photothermal deflection method
Detection of the laser-damage onset in optical coatings by the photothermal deflection method
复制标题
通过光热偏转法检测光学涂层中的激光损伤起始点
DOI：
10.1117/12.2068234
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
and T. Jitsuno
中科院分区：
文献类型：
--
作者：
K. Mikami;S. Papernov;S. Motokoshi;S. D. Jacobs;and T. Jitsuno
光热偏转（PD）方法是吸收评估的典型泵浦探针技术之一。在本研究中，PD 方法用于在严重破坏之前检测激光诱导损伤的特征。 PD 技术的设置被纳入纳秒损伤测试系统中，并结合 N-on-1 损伤测试来测量一些光学器件的吸收。首先，吸收随着脉冲激光照射而降低。然后，吸收在某个时刻增加。最后造成激光损伤，吸收下降。还评估了吸收的弛豫时间以揭示变化的原因。测量结果表明，减少的原因是初始污染物的处理，其效果可能被认为是激光调节所致。另一方面，吸收的增加可能归因于激光诱导缺陷（自陷激子）的产生。
Photo-thermal deflection (PD) method is one of the typical pump-probe techniques for absorption evaluation. In this study, the PD method was used for detection of a signature of laser-induced damage prior to critical destruction. A setup for the PD technique was incorporated into the nanosecond damage testing system and the absorption of some optics was measured in combination with N-on-1 damage test. The absorption decreased with pulse-laser irradiation at first. Then, the absorption increased at some point. Finally, the laser damage was caused and the absorption decreased. The relaxation times of the absorption were also evaluated to reveal the reason for the variation. The measured results indicated that the decrease came from the disposal of initial contamination and the effect might be considered as laser conditioning. On the other hand, the increase of the absorption might be attributed to generation of laser-induced defects (self-trapped excitons).