| 摘要 |
PROBLEM TO BE SOLVED: To correspond to the signal of a wide frequency band by providing plural transimpedance amplifiers, slightly shifting respective corresponding frequency bands so that they continue with the adjacent bands and connecting them in parallel. SOLUTION: A light-receiving element 1 receives an optical signal and converts the optical signal into a current signal. The transimpedance amplifiers 3-1 to 3-n convert and amplify the current signals received by the light-receiving element 1 into voltage signals. The respective transimpedance amplifiers 3-1 to 3-n correspond only to the frequency bands of a part of the received current signals (and therefore an amplification factor can be improved). The respective corresponding frequency bands are slightly shifted so that they continue with the adjacent bands and they are connected in parallel. Thus, the resistance values of feedback resistors 2-1 to 2-n are optimized so that they can correspond to all the frequency bands of the received current signals as a whole. |
