Solid-state image sensor

• US 7,683,954 B2
• Filed: 09/27/2007
• Issued: 03/23/2010
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Brainvision Inc., Stanley Electric Company Limited
• Inventors: Kawata, Tadashi, Tanite, Takanori, Ichikawa, Michinori
• Primary Examiner(s): Ometz; David L
• Assistant Examiner(s): Tejano; Dwight Alex C
• Application Number:
  US11/905,133
• Publication Number:
  US 20080079833A1
• Time in Patent Office: 908 Days
• Field of Search: 348/294, 348/295, 348/297, 348300-302, 348/307, 348/308, 356/4.01, 356/5.01, 257/431, 250/208.1
• US Class Current: 348/308
• CPC Class Codes: G01S 17/894 3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
• CPC Class Codes: G01S 7/4816 of receivers alone
• CPC Class Codes: G01S 7/4863 Detector arrays, e.g. charge-transfer gates
• CPC Class Codes: H01L 27/14623 Optical shielding
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H04N 23/745 Detection of flicker frequency or suppression of flicker wherein the flicker is caused by illumination, e.g. due to fluorescent tube illumination or pulsed LED illumination
• CPC Class Codes: H04N 25/00 Circuitry of solid-state image sensors [SSIS]; Control thereof
• CPC Class Codes: H04N 25/771 comprising storage means other than floating diffusion

Abstract

A solid-state image sensor of a charge sorting method used in a time-of-flight measurement method, in which noise derived from background light, which is caused by the reflection light from the subject derived from background light is eliminated, reflection light from the subject derived from a predetermined light source, which is previously set in the solid-state image sensor, is effectively extracted as a signal component to achieve high sensitivity and low noise, which is a solid-state image sensor that is equipped with a plurality of charge-storage sections, discriminates photoelectrons generated by incoming light on the incoming timing and sort to the above-described plurality of charge-storage sections, and measures the timing of the incoming light, in which the sensor has: a plurality of capacitors that capable of conducting to the plurality of charge-storage sections; and a control section that controls a conducted state between the above-described plurality of charge-storage sections and the above-described plurality of capacitors, in which by selectively conducting the above-described plurality of charge-storage sections and the above-described plurality of capacitors by the control of the above-described control section, the difference component of charge stored in the above-described plurality of charge-storage sections is extracted.

Claims

1. A solid-state image sensor that is equipped with a plurality of charge-storage sections, discriminates photoelectrons generated by incoming light on the incoming timing and sort to said plurality of charge-storage sections, and measures the timing of the incoming light, said sensor comprising:

a plurality of capacitors capable of conducting to the plurality of charge-storage sections; and

a control section that controls a conducted state between said plurality of charge-storage sections and said plurality of capacitors, wherein

by selectively conducting said plurality of charge-storage sections and said plurality of capacitors by the control of said control section, the difference component of charge stored in said plurality of charge-storage sections is extracted.

2. The solid-state image sensor according to claim 1, wherein

the electric capacitance values of said plurality of capacitors are equal to each other, and

the sensor is equipped with connection switching circuits, each of which is constituted by two FET switches, on the both terminals of said plurality of capacitors as said control section.

3. The solid-state image sensor according to claim 2, wherein

one terminal of said FET switch is connected to said plurality of charge-storage sections and the other terminal of said FET switch is connected to bias voltage.

4. The solid-state image sensor according to claim 1, wherein

said plurality of charge-storage sections are made up of two charge-storage sections,

said plurality of capacitors are made up of two capacitors, and

said control section repeats a first connected state where one side of said charge-storage section is connected to one side of said capacitor and the other side of said charge-storage section is connected to the other side of said capacitor and a second connected state where the other side of said charge-storage section is connected to one side of said capacitor and one side of said charge-storage section is connected to the other side of said capacitor, by each given amount of time.

5. The solid-state image sensor according to claim 2, wherein

said plurality of charge-storage sections are made up of two charge-storage sections,

said plurality of capacitors are made up of two capacitors, and

said control section repeats a first connected state where one side of said charge-storage section is connected to one side of said capacitor and the other side of said charge-storage section is connected to the other side of said capacitor and a second connected state where the other side of said charge-storage section is connected to one side of said capacitor and one side of said charge-storage section is connected to the other side of said capacitor, by each given amount of time.

6. The solid-state image sensor according to claim 3, wherein

said plurality of charge-storage sections are made up of two charge-storage sections,

said plurality of capacitors are made up of two capacitors, and

said control section repeats a first connected state where one side of said charge-storage section is connected to one side of said capacitor and the other side of said charge-storage section is connected to the other side of said capacitor and a second connected state where the other side of said charge-storage section is connected to one side of said capacitor and one side of said charge-storage section is connected to the other side of said capacitor, by each given amount of time.