雪崩光电二极管在相位式激光测距仪中的应用

Study on application of avalanche photodiode in phase laser distance measurement

雪崩光电二极管作为光敏接收器件,特别适合用于微弱信号的接收检测,它在相位式激光测距系统中用来接收经过漫反射后微弱的激光信号。针对雪崩二极管反向偏压电路中高纹波的问题,本文设计和分析了一种高效的低纹波偏压电路,实验结果表明,该方法有效抑制了纹波电压。针对雪崩二极管温度漂移的问题,本文设计和分析一种新型的温度补偿电路,使雪崩二极管达到了最佳雪崩增益。针对雪崩二极管噪声问题,分析了主要噪声源,设计了一个低噪声的前置放大电路,实验结果表明,该电路有效地提高了信噪比。综合实验结果表明,这些电路设计对于提高相位式激光测距仪的测量精度是有效的。

As a light-sensitive device, avalanche photodiode is particularly suitable for the receiving and detection of weak signal. Therefore, it is always used to receive weak laser signal in the phase laser distance measuring system. To solve the problem of high ripple in the bias voltage circuit, a high efficient circuit with low ripple is designed and analyzed which restrains the ripple effectively. To solve the problem of temperature drift, a new circuit with temperature compensation is designed and analyzed which enables APD to reach the optimal avalanche gain. To solve the problem of noise, the major noises of APD are analyzed and a preamplifier circuit with low noise is designed which raise the signalto-noise ratio effectively. The results of the experiment indicate that these circuit designs raise the measuring accuracy of the phase laser distance measuring system effectively.