本文件规定了测量光束宽度（直径）、发散角和光束传输比的方法。本文件适用于一般像散光束或未知类型的光束。对于柱头像散和简单像散光束，ISO？11146？1适用。 在本文件中，激光束的描述是通过维格纳分布的二阶矩，而不是光束宽度和发散角等物理量来完成的。然而，这些物理量与维格纳分布的二阶矩密切相关。在ISO/TR？11146？3中，给出了根据测量的二阶矩计算所有相关物理量的公式。

This document specifies methods for measuring beam widths (diameter), divergence angles and beam propagation ratios of laser beams. This document is applicable to general astigmatic beams or unknown types of beams. For stigmatic and simple astigmatic beams, ISO？11146？1 is applicable. Within this document, the description of laser beams is accomplished by means of the second order moments of the Wigner distribution rather than physical quantities such as beam widths and divergence angles. However, these physical quantities are closely related to the second order moments of the Wigner distribution. In ISO/TR？11146？3, formulae are given to calculate all relevant physical quantities from the measured second order moments.