Patent · US Expired

Image sensor having clamp circuit

US7394491B2 · kind B2 · utility

11Cited by
12References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 30, 2003
Grant dateJul 1, 2008
Priority date
Expiry dateFeb 18, 2026

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N25/78
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image sensor of the present invention prevents the phenomenon that surrounding background of a bright object reflecting or emitting strong light like the sun is presented at dark and improves image quality of the image sensor by controlling the brightness of the bright object. The image sensor using correlated double sampling technology which outputs data of an object by using difference between a reset voltage signal and a data voltage signal of a unit pixel includes a plurality of unit pixels arranged in a matrix, each outputting the reset voltage signal and the data voltage signal; a plurality of clamping means, each coupled to each unit pixels for clamping up the reset signal to a predetermined voltage level; and a voltage controlling block for adjusting voltage level supplied to a gate of each of clamping means.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.