Patent · US Expired

Image pickup apparatus with white balance control based on brightness

US6621519B2 · kind B2 · utility

14Cited by
7References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 20, 1998
Grant dateSep 16, 2003
Priority date
Expiry dateJan 20, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N23/88
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image pickup apparatus such as a video camera has the capability of automatic white balance control whereby the white balance is quickly adjusted for any object even just after an operator has turned on a power supply. An image pickup element converts an optical image of an object into an electrical image signal. The image signal is applied to a signal processing circuit and separated into a luminance signal and color signals. The separated color signals or the R and B signals are amplified by gain control circuits under the control of the correction signals supplied by a correction signal computing part, and then applied to a color-difference signal forming circuit which in turn produces color-difference signals (R−Y) and (B−Y). An encoder circuit generates a television signal in the standard form from the above color-difference signals and the luminance signal. In this processing, the white balance is adjusted according to a white balance control signal generated on the basis of information about a state of illuminance onto an object picked up last time and stored in a data storing part.

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