为了研究光电探测器反向偏置电压对能见度测量的影响, 使用光电探测器检测稳定的脉冲光束，改变光电探测器的反向偏置电压，通过精密示波器观察光电探测器输出信号的波形并读取输出信号的响应时间，用真有效值电压表测量相应波形有效值。结果表明，反向偏置电压的漂移会引起光电探测器响应时间的变化，进而影响光电探测器输出信号的有效值，给能见度测量带来不确定性。在选择光电探测器时要考虑反向偏压的影响，并保持反向偏压稳定。

In order to study the effect of photodetector reverse bias voltage on visibility measurement, a photodetector was used to detect the stable pulse beam, the reverse bias voltage of the photodetector was changed, and the response time and root mean square (RMS) of the output signal were read with the oscilloscope observing photodetector output signal waveform. The results show that the drift of the reverse bias voltage causes the photodetector response time changing, and RMS of the photodetector output signal is affected. The drift can affect the uncertainty of visibility measurement. When choosing photodetector in the designing of visibility meter, the influence of the reverse bias voltage should be considered, and the reverse bias voltage must be stable.