Patent · US Expired

Focusing controller

US5485240A · kind A · utility

0Cited by
5References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 3, 1994
Grant dateJan 16, 1996
Priority date
Expiry dateAug 3, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B7/32
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A focusing controller for photographic apparatuses includes: a distance meter which detects film-to-object distance to calculate and emit a distance signal; a lens shifting distance calculating device which calculates a lens shifting distance for effecting focusing in a focusing optical system on the basis of the distance signal by using one or two or more linear expressions; and a driving device for driving the focusing optical system in accordance with the lens shifting distance; the focusing controller allowing both the lens shifting amount for the focusing optical system and the reciprocal of film-to-object distance to be set at equal intervals.

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