岩石表面的BRDF特征模型研究

Study on BRDF Feature Model of Rock Surface

观察总结岩石在2π空间的BRDF光谱特征,构建了岩石表面的多角度双向反射分布函数特征模型.通过实验测定多种岩石在2π空间上的反射光谱与光线入射角、探测角、方位角等因子之间的关系数据,结果表明光线入射角对岩石的反射光谱影响较大,随着光线入射角的不同显著地影响岩石表面反射的波形曲线.并且,在相同探测角下,空间水平方位角对光谱具有极化特征,表现为椭圆分布;测定一些关键方向的e、p值,可完整描述岩石在不同入射角下的2π空间上的反射波谱特征,进而确定BRDF模型.构建多角度的BRDF反射特征模型,可以对现有的地质遥感影像进行光谱辐射数值纠正.

The multi-angle reflectance spectrum of rock surface in 2π space was studied in this paper. By studying the BRDF spectral characteristics of more than 10 kinds of rock in 2π space, we summed up the multi-angle rock surface bidirectional reflectance distribution function（BRDF） feature model. Four factors＇ data： reflectance spectrum, light incidence angle, detection angle, and azimuth angle were measured for these 10 kinds of rock in the experiment. The results showed that the impact of the incident angle of light was most important in the experiment. The reflection spectra of rock, varies significantly with the angle change of incidence of the light. Secondly, under the same detection angle, space horizontal azimuth impacts polarization characteristics on spectrum, and these spectra performed the elliptical distribution. We will be able to fully describe the reflection spectrum characteristics of rock under different incident angles in 2π space, and then determine the BRDF model, only using or measuring some of the key data of the direction of e, p value. If the BRDF reflection by the multi-angle feature model is established, we can use it to correct the existing geological remote sensing spectral image.