光电位置敏感器件背景光补偿的研究

光电位置敏感器件(PSD)是一种可直接对其光敏面上光斑位置进行检测的光电器件，基于光电位置敏感器件可以构成多种非接触的高精度动态位移监测仪器。根据光电位置敏感器件的原理及特征方程，分析了存在背景光时它的输出信号是非线性的。提出～种基于神经网络的光电位置敏感器件背景光非线性补偿方法。利用神经网络具有逼近任意非线性函数的特点．通过训练使神经网络建立在不同背景光下光电位置敏感器件输出与其标准值之间的非线性映射关系，对其实现全程跟踪补偿。计算机仿真表明，该方法能有效地消除背景光的影响，在神经网络的输出端得到期望的线性输出。

Study on Background Light Compensation of Photo-Electric Position Sensitive Detector

The position sensitive detector (PSD) is photo electronic sensor which can detect the position of a light spot travelling over its surface, and convert the position of light spot to simple electric current signal. The most important problem to use the PSD is how to overcome the influence of background light action on the PSD. Based on the PSD analyses, it is found that the signal of PSD is nonlinear when there exist background light. A method for background light compensation of photo electric position detector based on the artificial neural network is presented in this paper. In order to compensate background light over a full range, the neural network is trained to properly represent the nonlinear mapping between sensor reading and their represent output accurately at different background light. It is revealed from the computer simulation that the influence of background light fluctuation can be eliminated effectively, and a desired linear relationship between the sensor input and the neural network output can be obtained.