Solid-state image pickup element and camera system

A solid-state image pickup element having:

• a pixel portion in which a plurality of pixel circuits each having a mechanism for converting an optical signal into an electrical signal, and accumulating the electrical signal in accordance with exposure time are disposed in a matrix;
• a pixel driving portion which can be driven so as to carry out reset of the pixel portion, and accumulation and output of signal electric charges;
• and
• a pixel signal reading portion for reading signals of pixels from the pixel portion;
• the pixel circuit of the pixel portions including
• an output node,
• a photoelectric conversion element for converting the optical signal into the electrical signal, and accumulating therein the signal electric charges,
• a reset element which is turned ON/OFF in accordance with a reset signal, and resets the output node in an ON state, and
• a transfer element which is turned ON/OFF in accordance with a drive signal, and transfers the electric charges in the photoelectric conversion element in the ON state to the output node,
• the pixel driving portion being able to carry out
• first read drive with which reset read drive with which the reset element is turned ON in accordance with the reset signal to output a signal at the output node, and non-transfer read drive with which the transfer element is turned OFF in accordance with the drive signal to output the signal at the output node are carried out, and
• second read drive with which reset read drive with which the reset element is turned ON in accordance with the reset signal to output the signal at the output node, and transfer read drive with which the transfer element is turned ON in accordance with the drive signal to transfer the signal electric charges to the output node, thereby outputting the signal at the output node are carried out, and
• the pixel signal reading portion having
• a function of outputting a signal corresponding to a difference between a signal read out in accordance with the second read drive, and a signal read out in accordance with the first read drive.

A camera system having:

• a solid-state image pickup element;
• an optical system for imaging an image of a subject on the solid-state image pickup element;
• and
• a signal processing circuit for processing an output image signal from the solid-state image pickup element;
• the solid-state image pickup element having
• a pixel portion in which a plurality of pixel circuits each having a mechanism for converting an optical signal into an electrical signal, and accumulating the electrical signal in accordance with exposure time are disposed in a matrix,
• a pixel driving portion which can be driven so as to carry out the accumulation, and transfer and output of signal electric charges in the pixel portion, and
• a pixel signal reading portion for reading signals of pixels from the pixel portion,
• the pixel circuit of the pixel portions including
• an output node,
• a photoelectric conversion element for converting the optical signal into the electrical signal, and accumulating therein the signal electric charges, and
• a transfer element which is turned ON/OFF in accordance with a drive signal, and transfers the electric charges in the photoelectric conversion element in an ON state to the output node,
• the pixel driving portion being able to carry out
• first read drive with which the transfer element is turned OFF in accordance with the drive signal to output the signal at the output node, and
• second read drive with which the transfer element is turned ON in accordance with the drive signal to transfer the signal electric charges to the output node, thereby outputting the signal at the output node, and
• the pixel signal reading portion having
• a function of outputting a signal corresponding to a difference between a signal read out in accordance with the second read drive, and a signal read out in accordance with the first read drive.

A camera system having:

• a solid-state image pickup element;
• an optical system for imaging an image of a subject on the solid-state image pickup element;
• and
• a signal processing circuit for processing an output image signal from the solid-state image pickup element;
• the solid-state image pickup element having
• a pixel portion in which a plurality of pixel circuits each having a mechanism for converting an optical signal into an electrical signal, and accumulating the electrical signal in accordance with exposure time are disposed in a matrix,
• a pixel driving portion which can be driven so as to carry out reset of the pixel portion, and accumulation and output of signal electric charges, and
• a pixel signal reading portion for reading signals of pixels from the pixel portion,
• the pixel circuit of the pixel portions including
• an output node,
• a photoelectric conversion element for converting the optical signal into the electrical signal, and accumulating therein the signal electric charges,
• a reset element which is turned ON/OFF in accordance with a reset signal, and resets the output node in an ON state, and
• a transfer element which is turned ON/OFF in accordance with a drive signal, and transfers the electric charges in the photoelectric conversion element in the ON state to the output node,
• the pixel driving portion being able to carry out
• first read drive with which reset read drive with which the reset element is turned ON in accordance with the reset signal to output a signal at the output node, and non-transfer read drive with which the transfer element is turned OFF in accordance with the drive signal to output the signal at the output node are carried out, and
• second read drive with which reset read drive with which the reset element is turned ON in accordance with the reset signal to output the signal at the output node, and transfer read drive with which the transfer element is turned ON in accordance with the drive signal to transfer the signal electric charges to the output node, thereby outputting the signal at the output node are carried out, and
• the pixel signal reading portion having
• a function of outputting a signal corresponding to a difference between a signal read out in accordance with the second read drive, and a signal read out in accordance with the first read drive.