Automatic focus adjusting device
US5212516A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 1992 |
| Grant date | May 18, 1993 |
| Priority date | — |
| Expiry date | Feb 11, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/959
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An automatic focus adjusting device comprises an image sensor arranged to convert into a video signal an object image formed on its image sensing plane by a photo-taking lens optical system and to produce the video signal; a circuit which detects a high-frequency component included in the video signal; a circuit which detects from the video signal the degree of sharpness of the image on the basis of the width of the edge part of the image; a driving circuit which changes the position of the optical system relative to the image sensing plane in the direction in which the detection output of the high-frequency component and that of the degree of sharpness increase; and a control circuit which controls the driving speed of the driving circuit according to the detection output of the degree of sharpness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.