摘要
固体激光腔内放置薄膜偏振片对P偏振光存在4%~5%反射,当激光器输出P偏振光时,退偏损耗光束中包含较强P偏振光,无法测得腔内光束真实退偏率。实验研究Nd:YAG固体激光在输出P偏振光时,薄膜偏振片对P偏振光反射对腔内光束退偏率测量的影响。结果表明,当损耗光束中所包含P偏振光不被剔除时,不同透射率所对应退偏率曲线间存在较大差异;而当剔除这些P偏振光时,不同透射率所对应退偏率测量曲线趋于一致,测量结果可反映腔内光束的实际退偏率;在激光器输出s偏振光时,其退偏率测量值与当剔除损耗光束中P偏振成分后,输出P偏振光Nd:YAG谐振腔腔内光束退偏率测量值趋于一致。
Thin film polarizer reflects about 4%~5% p-polarized light, when the laser beam is incident on the thin film polarizer at Brewster's angle, which makes the laser beam reflected by intra-cavity thin film polarizer contain depolarized light (s-polarized light)and unignorable p-polarized light. This will result in intra-cavity depolarization rate measurement inaccurate. Intra-cavity depolarization rate measuring inaccuracy caused by intra-cavity thin film polarizer reflecting p-polarized light in an outputting p-polarized Nd : YAG resonator is experimentally investigated. The results show that, for different output mirror transmission in a outputting p-polarized light Nd : YAG resonator, there is obvious difference between the measured depolarization rate plots, when the p-polarized light caused by reflecting effect of thin film polarizer is not filtered from the depolarized light. And that tends to be consistent, if the p-polarized light are filtered from light reflected by the thin film polarizer. The investigation also shows that, for a outputting s-polarized Nd : YAG, the the depolarization rate can be directly measured, because the depolarization light, which is s-polarized light, contains little p-polarized light.
出处
《激光与光电子学进展》
CSCD
北大核心
2015年第9期218-222,共5页
Laser & Optoelectronics Progress
基金
广东省创新强校项目
关键词
激光器
退偏率
薄膜偏振片
P偏振光
S偏振光
lasers
depolarization rate
thin film polarizer
p-polarized light
s-polarized light