为提升光腔衰荡高反射率测量技术的精度,提出了一种基于耦合光腔衰荡技术的高反射率测量方法。该方法在耦合光腔衰荡系统中引入衰荡腔腔内模式监测模块,以腔内运行模式为判据寻找初始腔和测试腔耦合效率一致的状态,从而实现更高的测量精度。实验结果表明:在确保腔内模式处于基横模状态时,初始腔和测试腔腔内的等效损耗降低值几乎一致;对于同一高反射率待测样片,该技术对比传统方法可实现10.0%~27.1%测量精度的提升。

To improve the precision of traditional high-reflectivity measurement technology, we propose a high-reflectivity measurement method based on the coupled cavity ring-down technique. We introduce an intracavity mode monitoring module into the coupled cavity ring-down system to determine the state wherein the coupling efficiency between the initial cavity and the measured cavity is consistent. Subsequently, more precise measurements under the fundamental transverse mode condition of the cavity are achieved. The experimental results show that the intracavity equivalent loss remains almost the same while the initial cavity and the measured cavity are solely operating in the fundamental transverse mode. For the same high reflectance sample, the measurement precision of the coupled cavity ring-down technique can be 10.0%--27.1% higher than that of the traditional method.