Solid-state image sensing device and operation method thereof

A partial scanning method for reading a necessary charge from a predetermined first area of a solid-state image sensing device and discarding an unessential charge from a second area which is other than the first area, while scanning the solid-state image sensing device having pixel elements for storing charges, vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements toward a horizontal charge transfer device, the horizontal charge transfer device for transferring charges to output the charges to outside of the solid-state image sensing device, and a buffer storage device provided between the vertical charge transfer devices and the horizontal charge transfer device, said method comprising:

• a first charge transfer step of transferring charges from the vertical charge transfer devices to the buffer storage device;
• a second charge transfer step of transferring charges from the buffer storage device to the horizontal charge transfer device;
• a discarding step of discarding charges, out of the charges transferred in said second charge transfer step, obtained from the second area by operating the horizontal charge transfer device;
• a reading step of reading charges, out of the charges transferred in said second charge transfer step, obtained from the first area by operating the horizontal charge transfer device;
• a third charge transfer step of transferring charges in the vertical charge transfer devices toward the buffer storage device in said discarding step;
• and
• a fourth charge transfer step of, when there is a remaining charge in the horizontal charge transfer device after said reading step, transferring charges from the buffer storage device to the horizontal charge transfer device so that the remaining charge is added to a charge obtained from the second area,
• wherein said discarding step, said reading step, said third charge transfer step, and said fourth charge transfer step are repeatedly performed during period when charges in horizontal lines, of the solid-state image sensing device, including charges obtained from the first area, are transferred from the vertical charge transfer devices to the horizontal charge transfer device.

A solid-state image sensor comprising:

• pixel elements for storing charges;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element, for transferring charges to output the charges to outside of the solid-state image sensor;
• vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements toward said horizontal charge transfer device, each of said vertical charge transfer device having a plurality of transfer elements for sequentially passing charges from a transfer element to an adjoining transfer element;
• and
• a buffer device having electrodes with a capacitance smaller than the capacitance of electrodes of the vertical charge transfer devices, provided between said vertical charge transfer devices and said horizontal charge transfer device, for enabling to operate said vertical charge transfer devices during operating said horizontal charge transfer device;
• wherein said horizontal charge transfer device has a horizontal drain for draining charges which exceed a capacitance of said horizontal charge transfer device, and a gate capable of changing a wall of said horizontal drain by changing a potential applied to the gate.

A solid-state image sensor comprising:

• pixel elements for storing charges;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element, for transferring charges to output the charges to outside of the solid-state image sensor;
• vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements toward said horizontal charge transfer device, each of said vertical charge transfer devices having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element;
• and
• a gate having electrodes with a capacitance smaller than the capacitance of electrodes of the vertical charge transfer devices provided between said vertical charge transfer devices and said horizontal charge transfer device and connected to the transfer elements at ends of said vertical charge transfer devices;
• wherein said horizontal charge transfer device has a horizontal drain for draining charges which exceed a capacitance of said horizontal charge transfer device, and a gate capable of changing a wall of said horizontal drain by changing a potential applied to the gate.

An image sensing apparatus comprising:

• a plurality of pixel elements forming an image sensing area for storing charges;
• vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements in the vertical direction, each of said vertical charge transfer devices having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element, for transferring charges in the horizontal direction;
• and
• operation means for reading charges from a predetermined first area of the image sensing area and discarding charges from a second area which is other than the first area by transferring charges from said vertical charge transfer devices to said horizontal charge transfer device, discarding charges out of the transferred charges obtained from the second area by operating said horizontal charge transfer device, reading charges out of the transferred charges obtained from the first area by operating said horizontal charge transfer device, and when there is a remaining charge in the horizontal charge transfer device after reading all the charges from the first area, transferring charges from the vertical charge transfer devices to the horizontal charge transfer device so that the remaining charge is added to a charge obtained from the second area.

An image sensing apparatus comprising:

• a plurality of pixel elements forming an image sensing area for storing charges;
• vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements in the vertical direction, each of said vertical charge transfer devices having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element, for transferring charges in the horizontal direction;
• and
• operation means for reading a charge from a first area of the image sensing area and discarding a charge from a second area, which is other than the first area, by, when there is a remaining charge transferred from the second area at first timing in said vertical charge transfer device after all the charges transferred from said first area at the first timing are transferred from said vertical charge transfer devices to said horizontal charge transfer device, transferring charges from the pixel elements to the vertical charge transfer devices at second timing so that the remaining charge is added to a charge transferred from the second area at second timing in said vertical charge transfer devices.

An image sensing apparatus comprising:

• a plurality of pixel elements forming an image sensing area for storing charges;
• vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements in the vertical direction, each of said vertical charge transfer devices having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element, for transferring charges in the horizontal direction;
• a discarding portion, provided between said vertical charge transfer devices and said horizontal charge transfer device, used for discarding charges from a first area and reading charges from a second area of the image sensing area wherein both of the first area and the second area are included in a row of said plurality of pixel elements;
• and
• an operating unit for, while charges transferred from said pixel elements in a predetermined row remain in said horizontal charge transfer device, transferring charges stored in said pixel elements in another row to the horizontal charge transfer device.

A image sensing apparatus comprising:

• pixel elements for storing charges;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element, for transferring charges to output the charges to outside of the image sensing apparatus;
• vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements toward said horizontal charge transfer device, each of said vertical charge transfer device having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element;
• a buffer device provided between said vertical charge transfer devices and said horizontal charge transfer device;
• a plurality of first pulse input lines, connected to different charge transfer elements of said vertical charge transfer devices, each inputting a common pulse to every predetermined number of the plurality of transfer elements of said vertical charge transfer devices;
• a second pulse input line, provided independently of said first pulse input line, for providing a pulse to said buffer device to transfer a charge from said buffer device to said horizontal charge transfer device;
• and
• an operating unit for operating said first and second pulse input lines and said horizontal transfer device so as to operate paid vertical charge transfer devices during operating said horizontal charge transfer device.

An image sensing apparatus comprising:

• pixel elements for storing charges;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing charges from a transfer element to an adjoining transfer element, for transferring charges to output the charges to outside of the image sensing apparatus;
• vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements towards said horizontal charge transfer device, each of said vertical charge transfer devices having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element;
• a gate provided between said vertical charge transfer devices and said horizontal charge transfer device and connected to the transfer elements at ends of said vertical charge transfer devices;
• a plurality of first pulse input lines, connected to different charge transfer elements of said vertical charge transfer devices, each inputting a common pulse to every predetermined number of the plurality of transfer elements of said vertical charge transfer devices;
• a second pulse input line, provided independently of said first pulse input line, for providing a pulse to said gate to transfer a charge from said vertical transfer devices to said horizontal charge transfer device;
• and
• an operating unit for operating said first and second pulse input lines and said horizontal transfer device to operate said vertical charge transfer devices during operating said horizontal charge transfer device.

An image sensing apparatus comprising:

• a plurality of pixel elements forming an image sensing area for storing charges;
• a vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements in the vertical direction, each of said vertical charge transfer devices having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing charges from a transfer element to an adjoining transfer element, for transferring charges in the horizontal direction;
• a discarding portion used for discarding charges from a first pixel area and reading charges from a second pixel area, wherein both of the first and second pixel areas are included in each of the plurality of lines formed by said plurality of pixel elements;
• and
• an operating unit for, while a first charge transferred from a first line of the plurality of lines remain in a first transfer area of said horizontal charge transfer device after the first charge is transferred from a second transfer area of said horizontal charge transfer device, transferring a second charge transferred from a second line of the plurality of lines to the second transfer area.

An image sensing apparatus comprising:

• a plurality of pixel elements forming an image sensing area for storing charges;
• vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements in the vertical direction, each of said vertical charge transfer devices having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing charges from a transfer element to an adjoining transfer element, for transferring charges in the horizontal direction;
• an operating unit for controlling the transferring of charges from a first line to said horizontal charge transfer device under a state that charges from a second line are transferred midway within said horizontal charge transfer device, wherein each of the first and second lines is a separate line formed by said plurality of pixel elements.

An image sensing apparatus comprising:

• a plurality of pixel elements forming an image sensing area for storing charges;
• vertical charge transfer devices, arranged in parallel, for transferring charges stored in the pixel elements in the vertical direction, each of said vertical charge transfer devices having a plurality of transfer elements for sequentially passing a charge from a transfer element to an adjoining transfer element;
• a horizontal charge transfer device, having a plurality of transfer elements for sequentially passing charges from a transfer element to an adjoining transfer element, for transferring charges in the horizontal direction;
• and
• an operating unit for, while a first charge transferred from a first line of the plurality of lines remain in a first transfer area of said horizontal charge transfer device after the first charge is transferred from a second transfer area of said horizontal charge transfer device, transferring a second charge transferred from a second line of the plurality of lines to the second transfer area.