IEC 61746-1:2009提供了单模光时域反射计（OTDR）的校准程序。它只涵盖OTDR测量误差和不确定性。本标准不包括OTDR响应的校正。IEC 61746-1第一版取消并取代了2005年发布的IEC 61746第二版。它构成了一项技术修订。主要的技术变化是第4条的修改、第10条的取消、一些定义的改进和添加、一些计算的改变以及图形符号学对IEC/TR 61930的改变。 关键词:校准单模光时域反射计（OTDR）

IEC 61746-1: 2009 provides procedures for calibrating single-mode optical time domain reflectometers (OTDR). It only covers OTDR measurement errors and uncertainties. This standard does not cover correction of the OTDR response. This first edition of IEC 61746-1 cancels and replaces the second edition of IEC 61746, published in 2005. It constitutes a technical revision. The main technical changes are the adaptation of Clause 4, the suppression of Clause 10, the improvement and the addition of some definitions, the change of some calculations and the change of graphical symbology to IEC/TR 61930. Keywords: calibrating single-mode optical time domain reflectometers (OTDR)