Patent · US Expired

Video viewfinder system

US4692006A · kind A · utility

8Cited by
3References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 28, 1986
Grant dateSep 8, 1987
Priority date
Expiry dateFeb 28, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N23/63
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A video viewfinder system according to the preferred teachings of the present invention is shown for use with a camera of a standard design. The video viewfinder system includes video monitors for displaying derived images from a video camera of a primary image formed by the lens of the camera to allow the photographer to view the primary image formed by the camera lens at locations remote from the camera. Specifically, the video viewfinder system of the preferred form includes a viewfinder hood secured to the camera having a ground glass located at its first end for forming the primary image by the camera lens and with the video camera located at its second end and aimed at the primary image. To provide more uniform brightness of the derived image, a fresnel lens is associated with the ground glass for concentrating the outgoing light rays from the ground glass to the video camera and an anti-vignetting filter having gradating density from its center outward is provided for selectively absorbing the outgoing light rays from the ground glass to the video camera.

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