光反馈光腔衰荡和脉冲光腔衰荡技术测量腔镜高反射率的对比研究(英文)

Optical Feedback and Pulsed Cavity Ring-down Techniques for High-reflectivity Measurement:a Comparison Study

基于半导体激光器的光反馈效应,提出了光反馈光腔衰荡技术用于测量腔镜的高反射率。相对于没有光反馈的情况,光腔衰荡信号振幅提高了两个数量级,从而大大提高了高反射率测量精度。在四个衰荡腔长采用光反馈光腔衰荡技术测量得到的腔镜反射率非常一致,统计平均值为99.9356±0.0008%。通过实验比较了光反馈光腔衰荡和脉冲光腔衰荡技术。结果表明,光反馈光腔衰荡技术的测量精度比脉冲光腔衰荡技术高。

An optical feedback cavity ring-down （OF-CRD） technique, based on the OF effect of diode laser, was developed for accurate high-reflectivity measurement of cavity mirrors. The amplitude of the OF-CRD signal was enhanced to be about two orders of magnitude larger than that without OF effect. The high-reflectivity of the cavity mirror, measured by the OF-CRD at four RDC lengths, is in excellent agreement and statistically determined to be 99. 935 6±0. 000 8%. The OF-CRD and pulsed-CRD techniques, both based on the exponential decay measurement,were experimentally compared. The measurement accuracy of the OF-CRD is much higher than that of the pulsed-CRD, due to higher beam-propagation losses caused by modemismatching and mode beating effects in the pulse＆CRD experiment.