Solid-state image pickup device, a method of driving the same, a signal processing method for the same, and image pickup apparatus

• US 7,622,699 B2
• Filed: 04/22/2008
• Issued: 11/24/2009
• Est. Priority Date: 04/23/2007
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Oike, Yusuke, Sakakibara, Masaki
• Primary Examiner(s): LE, QUE TAN
• Application Number:
  US12/107,208
• Publication Number:
  US 20080258047A1
• Time in Patent Office: 581 Days
• Field of Search: 250/208.1, 250/214.R, 257290-292, 257/440, 348294-308
• US Class Current: 250/208.1
• CPC Class Codes: G01J 1/44 Electric circuits for command of an exposure part G03B7/02
• CPC Class Codes: H01L 27/14603 Special geometry or disposition of pixel-elements, address-lines or gate-electrodes
• CPC Class Codes: H04N 25/583 with different integration times
• CPC Class Codes: H04N 25/616 involving a correlated sampling function, e.g. correlated double sampling [CDS] or triple sampling
• CPC Class Codes: H04N 25/63 applied to dark current
• CPC Class Codes: H04N 25/633 by using optical black pixels
• CPC Class Codes: H04N 25/65 applied to reset noise, e.g. KTC noise related to CMOS structures by techniques other than CDS
• CPC Class Codes: H04N 25/67 applied to fixed-pattern noise, e.g. non-uniformity of response
• CPC Class Codes: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors
• CPC Class Codes: H04N 25/771 comprising storage means other than floating diffusion
• CPC Class Codes: H04N 25/778 comprising amplifiers shared between a plurality of pixels, i.e. at least one part of the amplifier must be on the sensor array itself

Abstract

Disclosed herein is a solid-state image pickup device including: a pixel array portion; a dummy pixel; a differential circuit; a reset voltage supplying section; and a common phase feedback circuit.

Claims

1. A solid-state image pickup device, comprising:

a pixel array portion constituted by arranging unit pixels each including a photoelectric conversion element, a transfer transistor for transferring signal charges obtained through photoelectric conversion in said photoelectric conversion element to a floating diffusion capacitor, a reset transistor connected between said floating diffusion capacitor and an output node, a capacitive element having a minuter capacitance than that of said floating diffusion capacitor, said capacitive element being connected between said floating diffusion capacitor and said output node, and an amplification transistor for reading out a voltage signal obtained through conversion in said capacitive element;

a dummy pixel having characteristics equal to those of said unit pixel, said dummy pixel being provided every pixel column of said pixel array portion;

a differential circuit composed of said unit pixel and said dummy pixel;

reset voltage supplying means for supplying a reset voltage to said reset transistor through said output node, said reset voltage supplying means being adapted to adjust a voltage value of the reset voltage; and

a common phase feedback circuit for controlling a current source for said differential circuit so that a center of a difference between differential outputs from said differential circuit becomes a control voltage adjusted by an external voltage source after completion of a reset operation by said reset transistor.

2. The solid-state image pickup device according to claim 1, wherein said common phase feedback circuit has a function of said reset voltage supplying means.

3. The solid-state image pickup device according to claim 1, wherein said dummy pixel is designed to have a larger size than that of said unit pixel.

4. A method of driving a solid-state image pickup device including a pixel array portion constituted by arranging unit pixels each including a photoelectric conversion element, a transfer transistor for transferring signal charges obtained through photoelectric conversion in said photoelectric conversion element to a floating diffusion capacitor, a reset transistor connected between the floating diffusion capacitor and an output node, a capacitive element having a minuter capacitance than that of said floating diffusion capacitor, said capacitive element being connected between said floating diffusion capacitor and said output node, and an amplification transistor for reading out a voltage signal obtained through conversion in said capacitive element;

a dummy pixel having characteristics equal to those of said unit pixel, said dummy pixel being provided every pixel column of said pixel array portion; and

a differential circuit composed of said unit pixel and said dummy pixel, said driving method comprising the steps of;

making a voltage value of a reset voltage supplied to said reset transistor through said output node variable; and

controlling a current source for said differential circuit so that a center of a difference between differential outputs from said differential circuit becomes a control voltage adjusted by an external voltage source after completion of a reset operation by said reset transistor.

5. An image pickup apparatus, comprising:

a solid-state image pickup device, having a pixel array portion constituted by arranging unit pixels each including a photoelectric conversion element, a transfer transistor for transferring signal charges obtained through photoelectric conversion in said photoelectric conversion element to a floating diffusion capacitor, a reset transistor connected between said floating diffusion capacitor and an output node, a capacitive element having a minuter capacitance than that of said floating diffusion capacitor, said capacitive element being connected between said floating diffusion capacitor and said output node, and an amplification transistor for reading out a voltage signal obtained through conversion in said capacitive element; and

an optical system for focusing an incident light onto an imaging area of said solid-state image pickup device;

wherein said solid-state image pickup device includes

a dummy pixel having characteristics equal to those of said unit pixel, said dummy pixel being provided every pixel column of said pixel array portion,

a differential circuit composed of said unit pixel and said dummy pixel,

reset voltage supplying means for supplying a reset voltage to said reset transistor through said output node, said reset voltage supplying means being adapted to adjust a voltage value of said reset voltage, and

a common phase feedback circuit for controlling a current source for said differential circuit so that a center of a difference between differential outputs from said differential circuit becomes a control voltage adjusted by an external voltage source after completion of a reset operation by said reset transistor.