用于355nm紫外激光器的消偏振二向色镜  

Depolarised Dichroic Mirror for the 355nm Ultraviolet Laser System

作　　者：庄秋慧[1,2] 刘国军[1] 付秀华[1] 马孜[3] 王三强[4] 

机构地区：[1]长春理工大学光电工程学院,长春130022 [2]重庆理工大学电子信息与自动化学院,重庆400050 [3]西南技术物理研究所,成都610000 [4]国网重庆市电力公司电力科学研究院,重庆401123

出　　处：《光子学报》2016年第7期160-164,共5页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.51275551;51505053);重庆市基础科学与前沿技术研究专项(No.cstc2015jcyjA40022)资助~~

摘　　要：采用离子束辅助电子束成膜,用双重膜厚监控方法监控各膜层厚度,制备了45°入射、808nm高反、1064nm高透的消偏振二向色镜,并用于全固态355nm激光器.将部分薄膜样品在250℃进行退火处理后,用Lambda950分光光度计测试该样品的光谱性能;用表面热透镜技术测量退火前后该样品的弱吸收值;用激光阈值损伤装置测试该样品在1064nm调Q激光下的损伤阈值;用NIKON显微镜观察样品在不同激光能量辐照下的破斑形貌.实验结果表明:波长为808nm和1 064nm时,薄膜透射率分别为0.04%和99.6%,符合设计要求,满足全固态355nm紫外激光器系统所要求的光学性能指标;退火后的弱吸收值较退火前有所降低;在激光作用下薄膜产生微破坏喷出,说明膜层不会向灾难性破坏演变.By using the ion beam assisted deposition to evaporate the materials and utilizing the double film thickness monitoring method to control the thickness of each layer, a depolarised dichroic mirror with the incidence angle of 45°, the spectrum 808nm reflected and 1064nm transmitted was prepared, which was used in an all solid state 355 nm laser. The partial thin film samples were annealed at 250℃, then the transmittance was measured with a Lambda 950 spectrophotometer; the weak absorption value of coatings was measured by a surface thermal lensing technique before and after annealing; the laser-induced damage threshold was tested by a 1 064 nm Q-switch pulsed laser; the morphology of the samples was observed by NIKON microscope under the different laser energy. The experimental results show that, the transmittances of the films are T1064 is 99.6%, T808 is 0.04%, which meet the design requirements, and the optical performance of the film can meet the requirements of the all solid state 355nm ultraviolet laser system;the weak absorption value is decreased after annealing; Micro destruction of the film is emitted under the action of laser, which proves that the film will not evolve to a catastrophic failure.

关 键 词：薄膜光学 紫外激光器 激光损伤 消偏振 光学性质 膜厚 

分 类 号：O484.4[理学—固体物理]