摘要
均匀材料表面除镜反射方向的其他散射方向光辐射强度都较微弱。采用信号参量估计中的最大似然估计,应用相关检测技术,利用被测信号与背景噪声不相关特性,设计了适于微弱光电信号检测的装置——锁相放大器。对金刚砂反射天顶角—55°～55°范围测量的实验结果与双向反射率(BRDF)模型比较显示,在可见光0.632 8μm波段,误差为3.43%;近红外1.34μm波段,误差只有0.01%。该锁相放大器适用于材料表面双向反射率的测量。
The radiation intensity of scattered light from the surface of uniform material is weak except for the mirror reflection direction. In this paper, an apparatus for detecting the small photo-electricity signal, lock-in amplifier is designed by using the most likelihood signal parameters estimation, the technology of correlative detection and the incoherence property between signal and noise. Comparison of BRDF model with the experimental results of the measurements on silicon carbide paper within the -55°-55° of reflectance zenith angle shows that the error is ：3. 43% at the visible 0. 632 8 μm and only 0. 01% at the near infrared 1. 34 μm. It is demonstrated that lock-in amplifier is fit for the detection of hi-directional reflectance of the material surface.
出处
《光学与光电技术》
2008年第1期55-58,共4页
Optics & Optoelectronic Technology
基金
黑龙江省自然科学基金(A-F200505)
中国博士后基金(20060390783)资助项目
关键词
双向反射率
弱信号
相关检测
噪声
锁相放大器
hi-directional reflectance
weak signal
correlative detection
noise
lock-in amplifier
