硅双结色敏型器件波长测量中环境光影响的研究

为了提高基于硅双结型色敏器件波长测量系统在有环境光噪声时的测量精度,对该类型波长测量系统中的环境光影响进行了理论分析和实验研究.通过对不同峰值波长和光强的高斯函数环境光下传统方法波长测量精度的仿真分析表明,环境光与被测光峰值波长相差越大、光强比越大,则测量结果的误差就越大.进而提出了一种消除环境光影响的改进方法,即去除含噪光(包含被测信号光和环境光)中环境光引起的两结光电流以求得被测信号光的两路光电流及其比的对数,再根据定标光源的峰值波长与其光电流比的对数的对应关系,获得待测信号光的峰值波长.最后,在日光(DLI)和日光灯光(FLI)同时存在的环境光中对传统方法和改进方法进行了测量精度的对比实验,结果表明,改进方法能够有效地消除环境光对波长测量结果的影响,显著提高在有环境光噪声存在时的系统测量精度.

Study of Ambient Light Influence on Wavelength Measurement Using Silicon Color Sensor with Dual Junctions

The influence of the ambient light on the wavelength measurement was analyzed theoretically and experimentally. An improved method was proposed to eliminate the influence of the ambient light. By removing the photocurrents caused by the ambient light among the noise-included signal light, the two photocurrents from the dual-junction sensor of the signal light was measured and their logarithmical ratio was first obtained. Then the peak wavelength of the signal light was ealcu lated based on the rdationship between the peak wavelengths of the calibrate light and the logarithmical ratios of their corresponding photocurrents. Finally,an experiment was carried out to compare the measurement accuracy of the traditional and improved methods in the environment involving both of the illumination of daylight and fluorescent lamps. The experimental results showed that the improved method eliminated the influence of the ambient light on the wavelength measurement effectively and therefore enhanced obviously the wavdength measurement accuracy in the environment with the existing of ambient light noise.