Patent · US Expired

Lens control device with AF restart feature

US6356307B2 · kind B2 · utility

11Cited by
3References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 21, 1998
Grant dateMar 12, 2002
Priority date
Expiry dateMay 21, 2018

Classification

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

Abstract

A lens control device comprising a variator lens group for zooming, a focusing lens group for compensating for a change introduced into the focused position as a result of a zooming operation by the variator lens group, a conversion lens group for changing a focusable shifting area of the variator lens group from a first area to a second area, a computing circuit for determining driving information for driving the focusing lens group during the shifting of the variator lens group, based on focused position data, according to object distance, of the focusing lens group relative to the position of the variator lens group, and a control circuit for shifting the variator lens group from the first area to the second area in response to the mounting of the conversion lens group and for controlling a computing operation of the computing circuit so that a focused position of the focusing lens group is determined when the variator lens group moves within the second area.

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