通过采用无源抑制方法对雪崩光电二极管的弱光探测技术进行了研究，分析了工作在盖革模式下的InGaAs APD的特性。利用APD两端的偏置电压VB在其雪崩后趋于稳定的特性，确定了其雪崩暗击穿电压，并且在水冷温控系统中，测得了APD雪崩暗击穿电压与温度的关系。结果表明，APD的雪崩暗击穿电压随着温度的上升而增大，光子群（弱光）到达时，APD探测到的在某一幅值处的脉冲数明显增加，其脉冲幅度也将增大。

The passive quenching method is used to study on the weak light detection technology based on avalanche photodiode(APD). The characteristics of InGaAs APD operating in Geiger mode is analized. Based on the properties of both ends of the APD bias voltage VB tend to be stabilized after avalanche, its dark avalanche breakdown voltage is identified. By using the water temperature control systems, the relationship between APD dark avalanche breakdown voltage and temperature is determined. The test results show that the APD dark avalanche breakdown voltage increases as the temperature rises, when the photon group(weak light) arrives, the number of pulse amplitude detected by APD will have a marked increasing , and the pulse height will also increase.