本文件规定了精确测定光学激光组件高反射率或高透射率（>；99？%）的测量程序。 本文件中给出的方法旨在用于测试和表征凹面镜和平面镜的高反射率，或激光系统和基于激光的仪器中使用的平面窗的高透射率。还可以通过考虑镜面曲率半径或透镜焦距来测试凸面镜的反射率或正透镜或负透镜的透射率。本文件是对ISO 15368的补充，ISO 15368规定了用分光光度法测定光学元件反射率和透射率的测量程序。ISO 15368适用于0%到100%范围内的反射率和透射率测量，典型精度为±0.3%，因此不适用于高于99.9%的反射率和透射率的精确测量。

This document specifies measurement procedures for the precise determination of the high reflectance or high transmittance (>99 %) of optical laser components. The methods given in this document are intended to be used for the testing and characterization of high reflectance of both concave and plane mirrors or high transmittance of plane windows used in laser systems and laser-based instruments. The reflectance of convex mirrors or transmittance of positive or negative lenses can also be tested by taking into consideration the radius of curvature of the mirror surface or the focal length of the lens. This document is complementary to ISO 15368 which specifies the measurement procedures for the determination of reflectance and transmittance of optical components with spectrophotometry. ISO 15368 is applicable to the measurements of reflectance and transmittance in the range from 0 % to 100 % with a typical accuracy of ±0,3 %, and is therefore not applicable to the precise measurements of reflectance and transmittance higher than 99,9 %.