Patent ID: 7224390

Claim:
A CMOS image sensor for getting images by outputting in order image signals sensed in each of pixel areas arranged like a matrix on the basis of X-Y addressing, the sensor comprising: pixel circuits each including: a photoelectric conversion element for carrying out the photoelectric conversion of incident light, a reset transistor for resetting a cathode of the photoelectric conversion element to initial voltage, an amplifying transistor for converting electric charges accumulated in the photoelectric conversion element to voltage, and a row selection transistor for outputting voltage output from the amplifying transistor as image signals corresponding to one pixel on the basis of a row selection signal to select signals output from the pixel areas arranged in a row direction; and a voltage control circuit for controlling a cutoff frequency for a low-pass filter formed by ON-state resistance of the reset transistor and parasitic capacitance produced at the cathode of the photoelectric conversion element during a period when the photoelectric conversion element is reset by controlling a potential of a gate of the reset transistor, wherein after setting the potential of the gate of the reset transistor to a power supply potential during the period when the photoelectric conversion element is reset to reset the cathode of the photoelectric conversion element to the initial voltage, the voltage control circuit sets the potential of the gate of the reset transistor to a frequency control potential for controlling the cutoff frequency.