Reflection type image forming optical system and projector
US6612704B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 10, 2002 |
| Grant date | Sep 2, 2003 |
| Priority date | — |
| Expiry date | Dec 10, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/7416
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A reflection type image forming optical system and a projector are compact with wide view angle, in expensive and having uniform illumination intensity. The reflection type image forming optical system includes a first reflection mirror having a rotation symmetric aspheric shape concave reflection surface directed to an image forming surface arranged an image forming element thereon, a second reflection mirror having a rotation symmetric aspheric shape convex reflection surface directed toward a flux of light from the first reflection mirror, a third reflection mirror having a rotation symmetric aspheric shape concave reflection surface directed toward a flux of light from the second reflection mirror and a fourth reflection mirror having a rotation symmetric aspheric shape convex reflection surface directed toward a flux of light from the third reflection mirror. The first, second, third and fourth reflection mirrors form a telecentric optical system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.