Patent ID: 8243190

Claim:
A solid state image pickup device, comprising: a pair of a plurality of photosensor arrays, each array including pixels; a control unit for determining an accumulation end of photocarrier accumulation of the plurality of photosensor arrays when a maximum value signal among signals outputted from each of the pixels of the plurality of photosensor arrays reaches an accumulation end voltage; a level shifter for level-shifting a signal outputted from each of the pixels of the plurality of photosensor arrays such that the maximum value signal is set to be an output reference voltage; and an amplifier for amplifying a plurality of signals, which have been level-shifted by the level shifter, and for outputting amplified signals, wherein the level shifter includes: an operational amplifier; a level shift capacitor electrically connected between a non-inverting input terminal of the operational amplifier and one of the pixels; a switch having a first terminal electrically connected to the non-inverting input terminal of the operational amplifier; a first circuit element electrically connected between an inverting input terminal of the operational amplifier and a second terminal of the switch; a second circuit element electrically connected between the inverting input terminal and an output terminal of the operational amplifier; and an input terminal electrically connected to the second terminal of the switch and supplied with the output reference voltage, wherein a gain of the amplifier is varied by the first and second circuit elements.