Patent ID: 8665243

Claim:
A sensor device having a plurality of sensor elements arranged in a matrix form, and a sensor driving section driving the plurality of sensor elements, each of the plurality of sensor elements comprising: a photoelectric conversion element generating electric charge according to an amount of received light; a storage node storing electric charge generated by the photoelectric conversion element, to show a voltage which fluctuates according to the stored electric charge; a reset transistor having an end connected to an end of the photoelectric conversion element and resetting the voltage in the storage node to a predetermined reset voltage; and a readout section reading the voltage value resulted from the stored electric charge in the storage node, to output the resultant voltage value as a sensor detection signal, wherein the sensor driving section controls the reset transistor so that the storage nodes of the sensor elements over a plurality of sensor element lines are reset into the predetermined reset voltage at a time, and then performs read control after a lapse of a predetermined exposure period so as to allow the sensor detection signals to be sequentially outputted from the respective sensor elements arranged in each of the sensor element lines, wherein the sensor driving section performs, after the lapse of the exposure period, control of holding the voltage in the storage nodes in the sensor elements over the plurality of sensor element lines at a time so as to be prevented from fluctuation due to the electric charge generated in the photoelectric conversion element, wherein the sensor driving section performs, while the voltage in the storage nodes are maintained in such a hold state, read control so as to allow the sensor detection signals to be sequentially outputted from the respective sensor elements arranged in each of the sensor element lines, wherein the sensor driving section controls, after the lapse of the exposure period, the voltage in the storage node to be maintained in the hold state, through electrically controlling an impedance between the photoelectric conversion element and the storage node to be higher than an impedance during the exposure period, and wherein each of the plurality of sensor elements further includes a switching transistor interposed between a connection point between the photoelectric conversion element and the reset transistor and the storage node, the switching transistor allowing the impedance between the photoelectric conversion element and the storage node to be electrically high, and the sensor driving section controls the impedance between the photoelectric conversion element and the storage node through switching control of the switching transistor.