利用光腔衰荡技术开展了中远红外波段的高反镜反射率测量研究。以中心波长9.7 μm 附近的脉冲量子级联激光器为光源,构建了高反射率测量实验装置。利用该装置对不同腔长下腔镜的反射率进行了测量,最终测定其反射率为99.946 4%,测量重复性误差优于0.001 4%。实验表明该测量装置重复性精度高,可用于中远红外高反镜反射率的精确测量。

The reflectivity measurement on high reflective mirrors in the mid-and-far infrared range was performed based on the Cavity Ring-down (CRD) technique. A pulsed quantum cascade laser with center wavelength of 9.7μm was used as the light source in the experimental setup,with which the reflectivity of the cavity mirrors at different cavity lengths was measured. The reflectivity was determined statistically to be 99.946 4% and the measured repeatability error is better than ±0.001 4%. The experimental results indicated that the CRD setup has a high repeatability and accuracy,and can be applied in high reflectivity measurements of mid-and-far infrared mirrors.