单发大口径光束下介质膜损伤阈值测试

针对传统的激光诱导损伤阈值测试中存在的耗时问题,提出了一种利用单发次、大口径光束的介质膜损伤阈值的快速测定方法。该方法以图像处理为基础,通过坐标变换和栅格压缩,建立了样品辐照区域内损伤分布与光斑强度分布之间的精确对应关系。基于对大口径光斑辐照区域内损伤信息的快速提取和统计方法,通过单次激光辐照,获取了待测区域的损伤阈值。根据此方法搭建了单发大口径光束损伤阈值测试平台,并对HfO2/SiO2高反射膜损伤阈值进行了单发次测定的验证。

Single-shot large beam laser induced damage threshold measurement on dielectric coatings

A novel method for laser induced damage threshold (LIDT) test of dielectric coatings is discussed in order to solve the time-consuming problem in traditional LIDT test. Single shot with large beam is used to get the LIDTs based on image processing technique. Following the coordinate conversion, image girding and compression procedure, the damage information could be extracted by comparing the sub-damage-spots distribution with the laser intensity distribution in the irradiated region. And finally the LIDT could be obtained from this information. This new method could greatly increase the efficiency of LIDT test. Moreover, the single-shot large beam LIDT testing bench is introduced and the availability of this method is confirmed on HfO2/SiO2 high reflectors.