双向反射分布函数的绝对测量方法

Measurement Method of Absolute Bidirectional Reflectance Distribution Function

在光谱光度计的校准中，需要在特定的入射和接收的几何条件下进行。在一些情况，校准的几何条件和光谱区受到了限制，因此有必要建立一种可适用于任意几何条件下和更宽光谱区的校准方法。本文介绍了一种校准光谱双向反射的方法，可适用于各种入射和接收的几何条件。从４００～２５００ｎｍ的光谱范围内，确定烧结的聚四氟乙烯标准样品的绝对双向反射系数，参考标准是通过国家计量院传递的方向—半球反射系数。

A method for calibrating spectral bidirectional reflectance in any illumination and viewing geometrics is proposed. The absolute bidirectional reflectance factor of a standard sample made by sintered polyte trafluoroethylene (PTFE) is determined in the range of 400-2500 nm. The reference standard is direction hemisphere reflectance factor transferred by the National Institute of Measurement. The absolute bidirectional reflectance factor can be measured on the instrument of measuring bidirectional reflectance distribution function at nearly all the illumination and viewing geometrics.