| 摘要 |
PURPOSE:To reduce the fluctuation of pulse duration for the reproduced pulse caused by the amplitude of signal and thus minimize the effect of the temperature fluctuation, by compounding the reference voltage by giving a partial voltage to the output of the reference circuit as well as the maximum value of the input signal. CONSTITUTION:The signal received by the photodiode 13 and converted into the electric signal is applied to the voltage comparator 4 via the preprocess circuit 2-1. At the same time, this signal is applied to the maximum value detecting circuit 3 which holds the maximum value VSM for a certain time, and the output of the circuit 3 is put into the terminal of one side is the partial voltage circuit 6. The output voltage VTHL of the reference preprocess circuit 2-2 is applied to the other terminal of the circuit 6. If the partial voltage ratio of the circuit 6 is set to 1/2, the reference voltage applied to the circuit 4 becomes as VTH=1/2(VSM+VTHL). |
