雪崩光电二极管以其接收灵敏度高、响应速度快等优点 ,常用于扫描式激光成像系统中。由于雪崩光电二极管的工作电压随背景和温度的变化而变化 ,因此正确设置其工作偏压 ,对充分发挥接收系统的探测灵敏度是重要的。主要讨论采用恒虚警率控制法自动设置雪崩光电二极管的偏压 ,调整噪声门限以获得光电接收系统最佳工作状态 Avalanche photodiode with its receiving sensitivity, fast response, etc., commonly used in scanning laser imaging system. Since the operating voltage of the avalanche photodiode varies with the background and the temperature, setting the operating bias properly is important to give full play to the detection sensitivity of the receiving system. The main discussion of constant false alarm rate control method automatically set the avalanche photodiode bias, adjust the noise threshold to obtain the best optical receiving system working condition