Automatic focusing apparatus
US4782356A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 1987 |
| Grant date | Nov 1, 1988 |
| Priority date | — |
| Expiry date | Sep 18, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/305
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An automatic focusing apparatus configured such that a projected light from a light emitting element is reflected on an object and the reflection light is passed through a flat plate so as to be received by a light receiving element. The position where the reflection light is received on the light receiving element varies depending on the distance between the apparatus and the object. This positional variation is corrected so as to receive the reflection light at the same position by changing an angle of inclination of the flat plate. A focusing lens is moved in cooperation with the adjustment of the inclination angle of the flat plate, thereby achieving the automatic focusing operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.