中红外量子级联激光器偏振合束实验研究

Study on polarization beam combining experimental of mid-infrared quantum cascade laser

合束是实现量子级联激光器高功率输出的关键技术,基于激光的偏振特性,研究了偏振合束的实验原理及实验方法。使用线栅偏振片和中波半波片组成偏振合束装置,对两路4.05μm量子级联激光器进行偏振合束,测试了中波半波片对4.05μm激光的透过率以及中波线栅偏振片对4.05μm激光透射率和反射率与入射角的关系,通过实验研究,当透射路光束和反射路光束与线栅偏振片的夹角为30°时,透射路的透射率为81%,反射路反射率为91%,其光束合束效率达到约86%,并使用光束质量分析仪对合束之后的光束质量进行测试分析。结果表明:两路光束通过该合束装置合束之后,在保证合束效率的条件下,具有较好的光束质量。

Beam combining is a key technology to achieve high-power output of quantum cascade lasers.Based on the polarization characteristics of lasers,the experimental principles and methods of polarization beam combining were studied.The polarization beam combining device was composed of a wire grid polarizer and a mid-wave half-wave plate to perform polarization combining of two 4.05μm quantum cascade lasers.The transmission rate of the mid-wave half-wave plate to 4.05μm laser and the relationship between the transmission rate and reflectance of the wire grid polarizer to 4.05μm laser and the angle of incidence were tested.When the angle of the wire grid polarizer was 30°,the transmittance was 81%,the reflectivity was 91%,and its beam combining efficiency reached about 86%.The beam quality after combining was tested and analyzed by a beam quality analyzer.The results show that the beam after beam combination has better beam quality under the condition of ensuring beam combination efficiency.