Voss K J, Chapin A, Monti M, Zhang H
Appl Opt. 2000 Nov 20;39(33):6197-206. doi: 10.1364/ao.39.006197.
A new instrument to measure the in situ bidirectional reflectance distribution function (BRDF) of surfaces is described. This instrument measures the BRDF for eight illumination angles from 0 to 65 deg, three colors (475, 570, and 658 nm), and at over 100 selected viewing angles. The viewing zenith angles range from 5 to 65 deg, and the azimuth angles, relative to the illumination direction, range from 0 to ?180 deg. Many tests of the system have been run and show that for flat surfaces the BRDF of a sample surface can be measured with a precision of 1-5% and an accuracy of 10% of the measured reflectance. The BRDF for a dry and wet sand sample is presented as a demonstration of the instrument.
本文描述了一种用于测量表面原位双向反射分布函数（BRDF）的新型仪器。该仪器可测量0至65度的八个照明角度、三种颜色（475、570和658纳米）以及100多个选定视角下的BRDF。观测天顶角范围为5至65度，相对于照明方向的方位角范围为0至180度。该系统已进行了多次测试，结果表明，对于平面，样品表面的BRDF测量精度可达1-5%，测量反射率的准确度为10%。作为该仪器的演示，给出了干燥和潮湿沙子样品的BRDF。
