基于检测光纤的漫射高光谱采集的Monte Carlo仿真  

Monte Carlo Simulation Based on Diffuse Hyperspectrum Collection with Detection Fiber

作　　者：林凌[1] 张林娜[1] 李晓霞[2] 李刚[1] 王为[3] 刘瑞安[3] 

机构地区：[1]天津大学精密测试技术及仪器国家重点实验室,天津300072 [2]河北工业大学电气工程学院电磁场与电器可靠性省部共建重点实验室,天津300130 [3]天津师范大学电子与通信工程学院,天津300387

出　　处：《光谱学与光谱分析》2014年第1期185-190,共6页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(30973964);天津市应用基础及前沿技术研究计划(11JCZDJC17100)资助

摘　　要：从漫射高光谱中可以获得被测物体成分、结构及其分布等信息。采用光纤光谱仪获取漫射高光谱是一种常用的方法。Monte Carlo方法在研究光在浑浊介质的传播方面得到了广泛的应用。然而,使用Monte Carlo方法研究漫射高光谱时,必须考虑实际的检测条件对信号采集的影响。将光纤参数引入到Monte Carlo模型中,研究了光纤参数对被检测光学信号的影响。仿真结果表明,孔径角和半径增大,检测的漫射高光谱随之增大,而光纤与被测物质表面的距离小于1mm时对漫射高光谱的影响在一定程度上可以忽略。进一步研究发现存在固定的修正系数使不同孔径角的光纤所采集的漫射高光谱转化为孔径角为π/2的光纤对应的信号。同时,得到了实际光纤孔径角范围内的修正系数拟合曲线。不同半径的光纤通过面积归一化可以得到很好的一致性。研究检测光纤参数对漫射高光谱的影响对实际测量有重要的指导意义,而且不同光纤所对应的检测结果可以通过修正系数和面积归一化进行移植。The present paper brings the parameters of the detection fiber into Monte Carlo model, and we studied the influence of fiber optic parameters and the distance of fiber from the detector on the detected optic signal, The simulation results show that signals are obviously different when the NA （numerical aperture） and diameter of the fiber are different respectively. With the increase in NA and diameter of the fiber, the diffuse reflectance and diffuse transmission increase gradually. However, the dis- tance from the sample surface, to some extent, brings little influence when we control it within 1 Ilma. By further study of the simulation result, we found that the collection efficient of the fiber is the same in different spatial positions. And the collection efficient of strong scattering material is a constant, in spite of absorption coefficient and scattering coefficient. We can normalize the diffuse signals collected by fibers with different angular aperture 13 by the collection efficient. Meanwhile, this paper provided the fitting curve of the collection efficient in a certain range. For fibers with different diameters, we can get a good consistence by area normalization. Therefore, the research on the effects of the difference of the detection fiber on diffuse hyper-spectrum has great significance for practical measurement. And the detection results can be transplanted by collection efficient and area nor- realization when we change the actual detecting fiber.

关 键 词：MONTE Carlo仿真 检测光纤 漫射高光谱 浑浊介质 

分 类 号：TH744.1[机械工程—光学工程]