Focus control method and video camera apparatus
US6275262A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 21, 1997 |
| Grant date | Aug 14, 2001 |
| Priority date | — |
| Expiry date | Mar 21, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/673
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A focus control circuit (34) which controls the focus of a video camera is provided with a horizontal-direction evaluation value generating circuit (62) which generates a plurality of evaluation values for the horizontal direction, a vertical-direction evaluation value generating circuit (63) which generates a plurality of evaluation values for the vertical direction, and a microcomputer (64) which performs a prescribed operation upon receiving the evaluation values for the horizontal and vertical directions. The circuit (62) generates the evaluation values corresponding to preset evaluation windows of different sizes. The microcomputer (64) selects evaluation values corresponding to an appropriate evaluation window for judging the contrast of an object out of the supplied evaluation values and controls the focus of the video camera based on the selected evaluation values. Therefore, appropriate evaluation values of the object can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.