Patent · US Expired

Automatic focusing device wherein lens movement is controlled in accordance with lens hunting

US5402175A · kind A · utility

6Cited by
4References
21Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 24, 1992
Grant dateMar 28, 1995
Priority date
Expiry dateNov 24, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N23/673
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An automatic focusing device including a focus detection circuit for detecting a focus state, and a motor for driving a focusing lens in accordance with an output from the focus detection circuit. The device controls the driving state of the motor in accordance with a result of comparing the amplitude of hunting of the focusing lens with a predetermined value when the direction of the drive of the focusing lens is reversed.

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