介绍了一种通过遗传模拟退火算法进行参数反演获取目标样片BRDF模型参数的方法。将BRDF五参数统计模型中遮蔽函数的四个参数作为未知参数,利用在激光波长下目标样片的BRDF实验测量数据,通过遗传模拟退火算法进行模型参数反演,获得上述样片BRDF统计模型的九个模型参数,结果表明,与遮蔽函数四个参数取经验值情况相比较发现,九参数BRDF统计模型的均方误差更小一些,并且通过反演出的遮蔽函数四个参数,得到上述样片在几种入射角情况下遮蔽函数随散射角的分布情况,所反演的遮蔽函数四个参数能反映材料表面的粗糙程度。
A method of acquiring parameters of the five-parameter BRDF statistic model in object sample using the genetic simulated annealing algorithm was introduced. using four parameters in the shadowing function as unknown parameters in BRDF model, a nine-parameter BRDF model was obtained when the genetic simulated annealing algorithm was applied to the parameter reversion of the BRDF statistic model of the object surface according to the BRDF experimental data at laser wavelength 1.06 μm. The results show that, mean square errors of the nine-parameter BRDF model were small compared with that of five-parameter BRDF model. The distribution of shadowing function with scattering angle is obtained for different incident angles by retrieving the four parameters of shadowing function, which reflect the surface roughness of object sample.