Patent · US Expired

Image pickup apparatus

US4423436A · kind A · utility

27Cited by
7References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 4, 1981
Grant dateDec 27, 1983
Priority date
Expiry dateMay 4, 2001

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N23/555
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An image pickup apparatus having a light source for providing an illumination light; an endoscope including illumination fiber optics for transmitting the illumination light to a foreground subject, and image fiber optics for sensing an optical image of the subject and transmitting this image; a video circuit for converting the optical image into a video signal; and a feedback circuit for converting the video signal into a light source drive signal and for continuously feeding the light source drive signal back to continuously set the light source so that the video signal is maintained at a substantially constant prescribed level. The light source, illumination fiber optics, image fiber optics, video circuit and feedback circuit jointly constitute an automatic level control loop which is continuously actuated as to continuously set the video signal to the substantially constant prescribed level.

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