Patent · US Expired

Lens controller

US5196879A · kind A · utility

8Cited by
10References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 4, 1991
Grant dateMar 23, 1993
Priority date
Expiry dateJun 4, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B7/102
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A lens controller comprises a focusing device for driving a focusing lens group; a zooming device for driving a zoom lens group; a focusing position detector for detecting the position of the focusing lens group on an optical axis; a zoom position detector for detecting the position of the zoom lens group on the optical axis corresponding to a focal distance thereof; a calculating device for respectively receiving outputs of the zoom and focusing position detectors and calculating a correction amount with respect to a shift in position of a formed image after the zoom lens group is driven by the zooming device; a control device for receiving the correction amount and controlling the operation of the focusing device such that the focusing lens group is moved to a focusing position with respect to the focal distance thereof; a device for judging whether or not the focusing lens group is located in inhibit regions on infinite and proximate sides respectively formed within a predetermined distance in a direction from an infinite position to a proximate position and in a direction from the proximate position to the infinite position; and a device for receiving an output of the judging d…

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