Patent · US Expired

Dual focus range apparatus for TV camera

US4972268A · kind A · utility

4Cited by
7References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 21, 1989
Grant dateNov 20, 1990
Priority date
Expiry dateJun 21, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N23/54
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A focusing system for closed circuit video cameras. A carrier block to which the image sensing device is attached is moved parallel to the lens axis for focusing images at close range because of the use of lenses normally focused at infinity or changes of focus required by system tolerances. The carrier block motion is accomplished by the use of two cams on a single shaft. The cams press against the carrier block and move the carrier block on guide rods as the cam shaft is turned. In order to attain two focusing ranges, the cam shaft itself is located within two pivoting saddles rather than being fixed. The saddles pivot on a fixed shaft which permits the entire focusing mechanism to be moved in one step between two preset positions. Each of the two positions is selected to be appropriate for one of two lenses.

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