| 摘要 |
PURPOSE:To improve the frequency response characteristic of a photodetector by connecting plural photodetectors in series so as to reduce apparently the parasitic capacitance of the photodetectors. CONSTITUTION:Photodiodes 1 having the same shape and characteristic are connected in series to constitute a photodetection section 2, an output of the photodetection section 2 is subject to current-voltage conversion by an operational amplifier 5 and the optical signal to the photodetection section 2 is outputted to an output terminal 6 as the amplitude of voltage. The frequency characteristic from the photodetection section 2 to the output terminal 6 is improved more than the characteristic IV in using a single photodiode 1 as shown in graph I. |
