Automatic focus detecting device
US6157783A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 22, 1998 |
| Grant date | Dec 5, 2000 |
| Priority date | — |
| Expiry date | Dec 22, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/346
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An automatic focus adjusting device adapted to detect focus information of an objective lens on the basis of two images of a subject, comprises a photosensor having a number of pixels on which the two images are formed, a focus detecting area setup device for selectively setting up either of first and second focus detecting areas on said photosensor, the first focus detecting areas being initially set up and the second focus detecting areas being less in the number of pixels than the first focus detecting areas, an operation device for performing predetermined operations on outputs of the first focus detecting areas set up on the photosensor to provide focus information of the objective lens, an evaluator for evaluating whether the results of operations are proper or not, and a controller responsive to the evaluator for, when the results of operations are improper, causing the focus detecting area setup device to set up the second focus detecting areas on the photosensor and then causing the operation device to perform the operations on outputs of the second focus detecting areas. This device permits the time taken to detect the focus to be reduced without the need of making a low …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.