Multi-directional focus state detection apparatus
US4859842A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 21, 1989 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Feb 21, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/346
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A focus detection apparatus includes: PA0 a first optical device for forming light distributions, associated with an object image, whose relative positional relationship chnages along a first direction in accordance with a focusing state of the objective lens; PA0 a second optical device for forming light distributions, associated with the object image, whose relative positional relationship changes along a second direction in accordance with the focusing state of the objective lens; PA0 a first sensing unit, having a plurality of photosensors, for forming an electrical signal associated with the focusing state of the objective lens in order to sense the light distributions formed by the first optical device; and PA0 a second sensing unit, having a plurality of photosensors, for forming an electrical signal associated with the focusing state of the objective lens in order to sense the light distribution formed by the second optical device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.