Solid-state image sensing device including reset circuitry and image sensing device including the solid-state image sensing device and method for operating the same

• US 7,839,442 B2
• Filed: 09/27/2005
• Issued: 11/23/2010
• Est. Priority Date: 10/05/2004
• Status: Expired due to Fees

• Current Assignee: Sony Semiconductor Solutions Corporation (Sony Group Corp.)
• Original Assignee: Konica Minolta Holdings Incorporated (Konica Minolta Inc.)
• Inventors: Kakumoto, Tomokazu, Tanaka, Yoshihiro, Kusuda, Masayuki, Yano, So, Sato, Kazuchika
• Primary Examiner(s): Misleh; Justin P
• Application Number:
  US11/236,388
• Publication Number:
  US 20060072025A1
• Time in Patent Office: 1,883 Days
• Field of Search: None
• US Class Current: 348/308
• CPC Class Codes: H04N 25/672 between adjacent sensors or output registers for reading a single image

Abstract

An object of the present invention is to provide a solid-state image sensing device configured to change a bias voltage given to the photoelectric converting section at the time of resetting so that an operative condition of the photoelectric converting section after the resetting can be maintained a constant condition regardless of an amount of the incident light. To achieve the object, an MOS transistor T5 is provided. The drain of the MOS transistor T5 is connected with a gate and a drain of an MOS transistor T2 and the source of the MOS transistor T5configured to be applied a DC voltage VRS. Here, a signal Φ V is given, an MOS transistor T4is turned on, and image data is output. A signal Φ RS is given and the MOS transistor T5 is turned on. As a result, a gate voltage Vg of the MOS transistor T2 is maintained as a constant voltage value. Then, a reset operation for pixels is stared.

Claims

1. A solid-state image sensing device comprising:

a signal control unit and

a pixel, the pixel including;

a photoelectric converting element for producing a photoelectric charge according to an amount of incident light,

a first transistor adapted to connect to the photoelectric converting element and adapted to generate an electric signal according to the photoelectric charge from the photoelectric converting element,

an output unit for outputting the electric signal from the first transistor,

a switch located between the photoelectric converting element and the first transistor, and

a reset voltage supplying unit connected to a node between the photoelectric converting element and the first transistor

wherein the signal control unit is programmed;

to cause the switch to electrically connect the photoelectric converting element and the first transistor during an image sensing operation and a first reset step,

to cause the reset voltage supplying unit to supply a voltage substantially equal to a voltage value produced at a node between the photoelectric converting element and the switch when light having a higher brightness value than a photographable brightness range is incident on the photoelectric converting element to a node between the photoelectric converting element and the first transistor to inject an electric charge into the photoelectric converting element and the first transistor during the first reset step after an image reading operation is completed,

to cause the switch to electrically disconnect the photoelectric converting element and the first transistor to reset an operative condition of the first transistor during a second reset step, and

to cause the switch to electrically connect the photoelectric converting element and the first transistor to reset a remaining electric charge in the photoelectric converting element during a third reset step.

2. A solid-state image sensing device according to claim 1,

wherein the reset voltage supplying unit includes a first electrode configured to have applied a predetermined voltage and a second electrode configured to be connected with a node between the photoelectric converting element and the first transistor, and

wherein the reset voltage supplying unit is a second transistor configured to be turned on and off in a predetermined timing.

3. A solid-state image sensing device according to claim 1, wherein the image reading operation includes outputting from the output unit an electric data to be used as screen image data obtained by an image sensing operation performed by the photoelectric converting element and the first transistor.

4. An image sensing device including a solid-state image sensing device for outputting an electric signal obtained in an image sensing operation as image data and outputting an electric signal obtained after a reset operation as correcting data, and a subtracter for outputting a value obtained by subtracting the image data and the correcting data from the solid-state image sensing device,

wherein the solid-state image sensing device is the solid-state image sensing device claimed in claim 1.

5. An image sensing device including a solid-state image sensing device for outputting an electric signal obtained in an image sensing operation as image data and outputting an electric signal obtained after resetting as correcting data, a subtracter for outputting image signal obtained by subtracting the image data and the correcting data from the solid-state image sensing device, and a signal processing unit for performing signal processing on the image signal from the subtracter, comprising:

the solid-state image sensing device which is the solid-state image sensing device claimed in claim 1,

a comparator for comparing the correcting data output from the solid-state image sensing device with a reference value, and

a determining unit for determining whether or not to select the image signal from the subtracter as image data for signal processing according to a comparison result in the comparator.

6. An image sensing device according to claim 5, wherein, in a case that the determining unit confirms that a value of the correcting data is in a brightness range which is substantially changed from a brightness value according to the comparison result in the comparator, not an image signal from the subtracter but an image signal set in a value based on a highest brightness value is selected as an image signal for the signal processing.

7. An image sensing device according to claim 5, comprising:

a memory for previously storing the correcting data, wherein, in a case that the determining unit confirms that a value of the correcting data is in a brightness range which is substantially changed from a brightness value according to the comparison result in the comparator, not an image signal from the subtracter but an image signal obtained by subtracting the image data output from the solid-state image sensing device and the correcting data stored in the memory is selected as an image signal for the signal processing.

8. An image sensing device according to claim 7, wherein the correcting data stored in the memory is a correcting data stored in a condition that a value of the correcting data is in a brightness range which is approximately constant to brightness value, according to the comparison result in the comparator.

9. A method of resetting a solid-state image sensing device having a pixel, the pixel including a photoelectric converting element and a first transistor, the method comprising the steps of:

performing an image data reading operation to output electric data to be used as image data obtained by an image sensing operation performed by the photoelectric converting element and the first transistor while the photoelectric converting element and the first transistor are electrically connected;

supplying a voltage substantially equal to a voltage value which is produced in a node between the photoelectric converting element and the first transistor when light having a higher brightness value than a photographable brightness range is emitted to the photoelectric converting element to a node between the photoelectric converting element and the first transistor after the image data reading operation to inject an electric charge into the photoelectric converting element and the first transistor;

electrically disconnecting the photoelectric converting element and the first transistor to reset an operative condition of the first transistor; and

electrically connecting the photoelectric converting element and the first transistor to reset a remaining electric charge in the photoelectric converting element.

10. A method according to claim 9,

wherein the pixel includes a switch for electrically connecting and disconnecting the photoelectric converting element and the first transistor,

wherein when the pixel performs an image sensing operation, the switch is turned on to connect the photoelectric converting element and the first transistor, and

wherein when the pixel performs a reset operation, the switch is turned off to disconnect the photoelectric converting element and the first transistor to reset an operative condition of the first transistor, and the switch is turned on to connect the photoelectric converting element and the first transistor to reset remained electric charge in the photoelectric converting element.

11. A pixel for use in a solid-state image sensing device, the pixel comprising:

a photoelectric converting element that produces a photoelectric charge according to an amount of incident light,

a first transistor connected to the photoelectric converting element that generates an electric signal according to the photoelectric charge from the photoelectric converting element,

an output unit that outputs the electric signal from the first transistor,

a reset voltage supplying unit that supplies a voltage substantially equal to a voltage value produced in a node between the photoelectric converting element and the first transistor when light having a higher brightness value than a photographable brightness range is incident on the photoelectric converting element to a node between the photoelectric converting element and the first transistor during a first reset step to inject electric charge into the photoelectric converting element and the first transistor after an image data reading operation, and

a switch that electrically connects the photoelectric converting element and the first transistor during an image sensing operation and the first reset step, and electrically disconnects the photoelectric converting element and the first transistor to reset an operative condition of the first transistor and electrically connects the photoelectric converting element and the first transistor to reset a remaining electric charge in the photoelectric converting element during a second reset step.

12. An image sensing device including a solid-state image sensing device that outputs an electric signal obtained in an image sensing operation as image data and output an electric signal obtained after a reset operation as correcting data, and a subtracter that outputs a value obtained by subtracting the correcting data from the image data,

wherein the solid-state image sensing device includes a pixel as claimed in claim 11.

13. The image sensing device according to claim 12, further comprising:

a signal processing unit adapted to perform signal processing on the value outputted from the subtracter;

a comparator adapted to compare the correcting data output from the solid-state image sensing device with a reference value, and

a determining unit adapted to determine whether or not to select the value outputted from the subtracter as an image signal for signal processing according to a comparison result in the comparator.

14. The image sensing device according to claim 13, wherein the image sensing device is adapted to set the image signal for signal processing to a value based on a highest brightness value when the determining unit confirms that a value of the correcting data is in a brightness range which is substantially changed from a brightness value according to the comparison result in the comparator.

15. A method of resetting a pixel in a solid-state image sensing device, the pixel including a photoelectric converting element and a first transistor, the method comprising the steps of:

performing an image data reading operation to output electric data to be used as image data obtained by an image sensing operation performed by the photoelectric converting element and the first transistor while the photoelectric converting element is electrically connected to the first transistor;

supplying a voltage substantially equal to a voltage value produced in a node between the photoelectric converting element and the first transistor when light having a higher brightness value than a photographable brightness range is incident on the photoelectric converting element to a node between the photoelectric converting element and the first transistor after the image data reading operation to inject an electric charge into the photoelectric converting element and the first transistor;

electrically disconnecting the photoelectric converting element and the first transistor to reset an operative condition of the first transistor; and

electrically connecting the photoelectric converting element and the first transistor to reset a remaining electric charge in the photoelectric converting element.