Patent ID: 6967682

Claim:
A photoelectric converting device comprising: a photoelectric conversion circuit (PCC) for generating an analog electric signal in accordance with an amount of incident light, said PCC being selectively operable, irrespective of the amount of the light, in either one of (1) a first mode in which said PCC generates the analog electric signal in such a way that intensity thereof is logarithmically proportional to the amount of the light and (2) a second mode in which said PCC generates the analog electric signal in such a way that intensity thereof is linearly proportional to the amount of the light, the PCC comprising: a photoelectric conversion element having a direct-current voltage applied to a first electrode thereof; and a first transistor capable of logarithmic conversions and having a first electrode, a second electrode, and a control electrode, the first electrode of the transistor being connected to a second electrode of the photoelectric conversion element; wherein switching between the first and second modes is achieved by varying a potential at the second electrode of the first transistor.