| 摘要 |
<p>An I/F converter 10 contained in a photodetector is provided with a first comparing portion 11 1 , a second comparing portion 11 2 , a current mirror circuit 14, an SR type flip-flop circuit 16, a buffer amplifier 18, a first capacitor C 1 , a second capacitor C 2 , a switch SW 1 , a switch SW 2 , a switch SW 11 and a switch SW 21 . The operation characteristics of the first comparing portion 11 1 and the second comparing portion 11 2 are identical to each other. The capacitance values of the two capacitors C 1 and C 2 are equal to each other. The input terminal 10a of the I/F converter 10 is connected to a photodiode, and the I/F converter 10 inputs current generated by the photodiode through the input terminal 10a thereof and outputs a signal having the frequency corresponding to the magnitude of the input current from a buffer amplifier 18.</p> |
