CURRENT-VOLTAGE CONVERSION DEVICE

PROBLEM TO BE SOLVED: To provide a current-voltage conversion device having a reduced value to the utmost of an offset voltage generated at the reset time, concerning the current-voltage conversion device constituted by an integration circuit. SOLUTION: In this current-voltage conversion device, the integration circuit is constituted by an operation amplifier and an integrating capacitor connected to an input terminal of the operation amplifier, and an input current is integrated into the integrating capacitor by the integration circuit, and a value of the input current is converted into a voltage value by an integration voltage generated on an output terminal of the operation amplifier. The device is constituted by a diode switch having one end connected to the connection side between the integrating capacitor and the input terminal of the operation amplifier, a non-inversion type amplifier having an output terminal connected to the other end of the diode switch and an input terminal connected to the output terminal side of the operation amplifier, and a gain switching means for switching the gain of the amplifier.