Patent ID: 7642496

Claim:
A photodetector comprising: N photodiodes (N being an integer of 2 or greater) each generating an electric charge by an amount corresponding to an intensity of light incident thereon; N electric charge amount level determining circuits, respectively arranged so as to correspond to the N photodiodes, for determining respective levels of amounts of electric charges generated in the photodiodes and outputting respective level signals indicative of results of level determinations; an integrating circuit including an input terminal, an output terminal, and an integral capacitance part having a variable capacitance value, which is set according to the level signal, accumulating an electric charge fed from the input terminal into the integral capacitance part, and outputting a voltage corresponding to an amount of the accumulated electric charge, from the output terminal; first switches respectively provided so as to correspond to the N photodiodes, and arranged between the respective photodiodes and the input terminal of the integrating circuit; and second switches respectively provided so as to correspond to the N electric charge amount level determining circuits, and arranged between the respective electric charge amount level determining circuits and the integral capacitance part; and wherein: the N photodiodes are arranged on a first substrate; the N electric charge amount level determining circuits, integrating circuit, first switches, and second switches are arranged on a second substrate; and the first and second substrates are connected to each other with a bump, the photodiodes and the first switches corresponding thereto are electrically connected to each other, and the photodetectors and the electric charge amount level determining circuits corresponding thereto are electrically connected to each other.