Imaging device

• US 8,710,422 B2
• Filed: 02/11/2013
• Issued: 04/29/2014
• Est. Priority Date: 08/16/2010
• Status: Active Grant

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Tezuka, Yojiro, Nakayama, Satoshi, Yamanaka, Hideki, Arii, Taku, Motohana, Ryoji, Funamizu, Wataru
• Primary Examiner(s): Sohn, Seung C
• Application Number:
  US13/763,936
• Publication Number:
  US 20130153750A1
• Time in Patent Office: 442 Days
• Field of Search: 250/208.1, 250/214.1, 250/214.R, 348/300, 348/308
• US Class Current: 250/208.1
• CPC Class Codes: H01L 27/14609 Pixel-elements with integrated switching, control, storage or amplification elements scanning details of imagers (circuitry of solid-state image sensors H04N25/00); circuitry of imagers H04N25/70
• CPC Class Codes: H04N 25/626 Reduction of noise due to residual charges remaining after image readout, e.g. to remove ghost images or afterimages
• CPC Class Codes: H04N 25/63 applied to dark current
• CPC Class Codes: H04N 25/745 Circuitry for generating timing or clock signals

Abstract

A horizontal driving control unit of an imaging device supplies dummy pulse signals to a horizontal driving unit at least at a part of period during a period from a start time point of each horizontal blanking period to a last signal sampling time point defined by a sampling control signal.

Claims

1. An imaging device, comprising:

a plurality of pixels being disposed two-dimensionally and each having a photoelectric conversion unit, a charge-voltage conversion unit converting a charge transferred from the photoelectric conversion unit into a voltage, a transfer unit transferring the charge from the photoelectric conversion unit to the charge-voltage conversion unit, an amplifying unit outputting a pixel signal according to the voltage of the charge-voltage conversion unit, and a reset unit resetting the voltage of the charge-voltage conversion unit;

a vertical driving unit supplying a driving signal driving the pixels to the plurality of pixels;

vertical signal lines being provided to correspond to respective columns of the plurality of pixels and to which the pixel signal is supplied;

a sample hold unit sampling and holding the pixel signal supplied to each of the vertical signal lines according to a sampling control signal, and supplying to horizontal signal lines according to a horizontal driving signal;

a horizontal driving unit supplying the horizontal driving signal to the sample hold unit; and

a horizontal driving control unit supplying a plurality of kinds of pulse signals relating to a reading of the pixel signal from the sample hold unit to the horizontal signal lines, wherein;

a circuit controlling the reset unit among the vertical driving unit is operated by an identical current source with the horizontal driving unit;

the horizontal driving control unit supplies the plurality of kinds of pulse signals to the horizontal driving unit at each horizontal reading period; and

the horizontal driving control unit supplies dummy pulse signals to the horizontal driving unit at least at a part of period during a period from a start time point of each horizontal blanking period to a last signal sampling time point at the horizontal blanking period from among signal sampling time points defined by the sampling control signal.

2. The imaging device according to claim 1, wherein

the dummy pulse signals are identical signals with one or more kinds of pulse signals from among the plurality of kinds of pulse signals.

3. The imaging device according to claim 2, wherein

the one or more kinds of pulse signals include at least one kind of pulse signal being supplied to the horizontal driving unit and to make the horizontal driving unit generate the horizontal driving signal.

4. The imaging device according to claim 3, wherein:

the horizontal driving unit includes a shift register unit; and

the at least one kind of pulse signal includes a driving clock signal driving the shift register unit.

5. The imaging device according to claim 1, wherein

the horizontal driving control unit stops the dummy pulse signals at the signal sampling time points.

6. The imaging device according to claim 1, wherein:

the signal sampling time points at each horizontal blanking period includes a second sampling time point sampling a photo signal containing photo information which is photoelectrically converted by the pixels, and a first sampling time point sampling a difference-purpose signal containing a noise component to be subtracted from the photo signal; and

a length of period from a time point when either of the one or more kinds of pulse signals or the dummy pulse signals are stopped just before the first sampling time point at each horizontal blanking period to the first sampling time point at the horizontal blanking period and a length of period from a time point when either of the one or more kinds of pulse signals or the dummy pulse signals are stopped just before the second sampling time point at each horizontal blanking period to the second sampling time point are the same.

7. The imaging device according to claim 1, wherein

the vertical driving unit supplies a driving signal controlling the reset unit to the reset unit to make the reset unit perform a reset operation at least at a part of period from among a period from a last signal sampling time point at the horizontal blanking period to an end time point of the horizontal blanking period at each horizontal blanking period.

8. The imaging device according to claim 1, wherein

the plurality of pixels commonly have the charge-voltage conversion unit, the amplifying unit, and the reset unit by every two or more predetermined number of pixels where each photoelectric conversion unit is sequentially arranged in a column direction.

9. An imaging device, comprising:

a plurality of pixels being disposed two-dimensionally and each having a photoelectric conversion unit, a charge-voltage conversion unit converting a charge transferred from the photoelectric conversion unit into a voltage, a transfer unit transferring the charge from the photoelectric conversion unit to the charge-voltage conversion unit, an amplifying unit outputting a pixel signal according to the voltage of the charge-voltage conversion unit, and a reset unit resetting the voltage of the charge-voltage conversion unit;

a vertical driving unit supplying a driving signal driving the pixels to the plurality of pixels;

vertical signal lines being provided to correspond to respective columns of the plurality of pixels and to which the pixel signal is supplied; and

a sample hold unit sampling and holding the pixel signal according to a signal of each of the vertical signal lines in accordance with a sampling control signal, and supplying the signal being held to horizontal signal lines according to a horizontal driving signal, wherein

the vertical driving unit supplies a driving signal controlling the reset unit to the reset unit to make the reset unit perform a reset operation at least at a part of period from among a period from a last signal sampling time point at the horizontal blanking period to an end time point of the horizontal blanking period at each horizontal blanking period.

10. The imaging device according to claim 9, further comprising:

a horizontal driving unit supplying the horizontal driving signal to the sample hold unit; and

a horizontal driving control unit supplying a plurality of kinds of pulse signals relating to a reading of a signal from the sample hold unit to the horizontal signal lines, wherein

a circuit controlling the reset unit among the vertical driving unit is operated by an identical current source with the horizontal driving unit.

11. The imaging device according to claim 9, wherein

the plurality of pixels commonly have the charge-voltage conversion unit, the amplifying unit, and the reset unit by every two or more predetermined number of pixels where each photoelectric conversion unit is sequentially arranged in a column direction.