光电信号接收器尺寸对光学薄膜弱吸收测量的影响  

Size Effects of Photoelectric Signal Receiver on Weak Absorption Measurement for Optical Coatings

作　　者：符燕燕 李大伟[1] 刘晓凤[1] 赵元安[1] 郭猛[1,2] 张蕾[1] 

机构地区：[1]中国科学院上海光学精密机械研究所,上海201800 [2]中国科学院大学,北京100049

出　　处：《中国激光》2015年第7期182-187,共6页Chinese Journal of Lasers

基　　金：国家自然科学基金(61308021)

摘　　要：基于表面热透镜技术搭建了光学薄膜弱吸收测量系统,使用不同功率的抽运光辐照样品,并通过光束质量分析仪记录经样品表面反射后的探测光强度的空间分布,以探测光强度最强点所对应的像素坐标为中心两边对称取多个像素点表示不同尺寸的接收器,从而分析不同尺寸光电信号接收器得到的光热信号强度。结果表明,随着接收器尺寸的增加,探测面积覆盖范围超过探测光束峰值区域,得到的光热信号与抽运光功率的比值逐渐偏离线性,从而引入的测量误差也就增大。因此,实际测量中应在保证测量极限的前提下尽量缩小探测器尺寸以提高测量的准确度。Based on the weak absorption measurement system with surface thermal lens（STL） technique, different power pump laser is used to irradiate the sample and record the intensity distribution of probe beam with beam quality analyzer. Making the pixel coordinates of the strongest intensity point of the probe beam as the center, by taking multiple pixel from both sides of the center, different sizes of photoelectric signal receiver can be represented and photo- thermal signal intensity which obtained by different sizes of photoelectric signal receiver can be analyzed. The photo-thermal signal as a function of size of photoelectric signal receiver is experimental measured.The experimental results show that with the size of photoelectric signal receiver increasing, the coverage area of detection exceeds the probe beam peak area,and then the photo-thermal signal deviates from linearity gradually,which enlarges the measurement error. Therefore, to improve the accuracy of measurements,the actual size of photoelectric signal receiver should be minimized on the premise of guaranteeing measurement limit.

关 键 词：光学器件 光学薄膜 弱吸收测量 表面热透镜 接收器口径 

分 类 号：O484.5[理学—固体物理]