Distance detecting device for an optical system
US6369854B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 1997 |
| Grant date | Apr 9, 2002 |
| Priority date | — |
| Expiry date | Mar 27, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/671
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The AF sensor module primarily comprises condenser lens 16, mirror 17, aperture mask 18, separator lens 19 and CCD 20. Separator lens 19 is located such that its lengthwise center line M may be parallel to the lengthwise center line N of CCD 20 while it is inclined by micro-angle &dgr; with center line M as the rotational axis. By arranging the lens surface of separator lens 19 and the image pickup surface of CCD 20 such that they are non-parallel to each other, reflected light L1 existing due to the reflection of light between separator lens 19 and CCD 20 is prevented from striking CCD 20 once again so that a reduction in the accuracy of focus detection caused by said reflected light may be prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.