2.7~3.0μm波段高反镜反射率测量研究  

Reflectivity measurement of highly reflective mirrors atspectral band of 2.7−3.0 μm

作　　者：周文超 魏千翯[3] 彭琛 黄德权 朱日宏[1] Zhou Wenchao;Wei Qianhe;Peng Chen;Huang Dequan;Zhu Rihong(School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China;Institute of Applied Electronics,CAEP,Mianyang 621900,China;School of Optoelectronic Science and Engineering,University of Electronic Science and Technology of China,Chengdu 610054,China)

机构地区：[1]南京理工大学电子工程与光电技术学院,南京210094 [2]中国工程物理研究院应用电子学研究所,四川绵阳621900 [3]电子科技大学光电科学与工程学院,成都610054

出　　处：《强激光与粒子束》2024年第1期97-102,共6页High Power Laser and Particle Beams

摘　　要：中红外激光领域广泛使用高性能高反射光学元件,高反射率高精度测试技术是制备高性能反射光学元件的基础。针对2.7~3.0μm波段光学元件高反射率测量的实际需求,基于量子级联激光器建立了连续光腔衰荡反射率测试实验装置,通过优选2.7~3.0μm波段反射带内水汽吸收较弱的测试波长,分析空气中水汽吸收对衰荡时间和反射率测量的影响,并比较空气和氮气环境下反射率测量结果,实现了2.7~3.0μm波段高反镜反射率的准确测量,在反射率约99.95%时绝对测量精度优于2×10-5。实验结果显示,采用测试波长2.9μm并在测量时保证初始腔和测试腔腔长相同,无需使用氮气环境,直接在实验室空气环境可实现高反射率的精确测量。The highly reflective(HR)mirrors with high-performance are widely employed in mid-infrared(mid-IR)laser systems.The manufacturing of mid-IR HR mirrors with high reflectivity requires techniques toprecisely measure their high reflectivity.In this paper,a continuous-wave cavity ring-down(CRD)experimentalapparatus in the 2.7−3.0μm spectral range is established based on a quantum-cascade laser for high reflectivitymeasurement.By precisely optimizing the laser wavelength within the reflection band of the mid-IR HR mirrors,analyzing the influence of water vapor absorption on the ring-down time and reflectivity measurements,andcomparing the reflectivity results measured under ambient air in clean-room laboratory and under nitrogen purging,theaccurate measurement of high reflectivity is achieved at the 2.7−3.0μm spectral band with an absolute reflectivitymeasurement accuracy of below 2×10−5 for about 99.95%reflectivity.The experimental results demonstrate that bysetting the laser wavelength precisely to 2.9μm and employing equal lengths of initial and test ring-down cavities(RDC)to avoid the influence of water vapor’s absorption lines,the reflectivity measurement for the 2.7−3.0μmspectral band can be performed under normal clean-room laboratory air,without the need of nitrogen purging.

关 键 词：中红外 高反镜 反射率 光腔衰荡 水汽吸收 

分 类 号：TN247[电子电信—物理电子学]