This sphere serves as a diffuse light source, which enables measurements of the hemispherical reflectance, or the directional absorptance, respectively.

这个球作为扩散光源，使测量的半球形或定向吸收率的反射系数，分别使用。

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The directional emissivity is deduced from the Bidirectional Reflectance Distribution Function (BRDF) in the hemispherical scattering space of the objects.

利用双向反射分布函数测量系统，通过对物体表面双向反射分布的测量来获得其方向发射率。

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