光敏二极管的开路电压随光照强度的增加,成对数式增大,当光强在一定范围内变化时,开路电压随光强变化的斜率很大,利用此特性的光探测电路,对光强的微弱变化十分敏感,适用于侵入监测和需要准确监控光强变化的情况.分析比较了几种可用于光探测的运算放大器电路,提出了实现微光及光微变的光敏二极管探测的方案. With the increase of light intensity, the open circuit voltage of photodiode increases logarithmically. When the light intensity changes within a certain range, the slope of the open circuit voltage varies greatly with the light intensity. By using the light detection circuit of this characteristic, Weak changes are very sensitive and suitable for intrusion monitoring and the need to accurately monitor changes in light intensity.This paper analyzes and compares several op amp circuits that can be used for light detection and proposes a photodiode detection scheme for achieving shimmering and lightly varying photons.