Projection optical system, magnification projection optical system, magnification projection apparatus, and image projection apparatus
US7637621B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 2008 |
| Grant date | Dec 29, 2009 |
| Priority date | — |
| Expiry date | Sep 19, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B17/0852
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A projection optical system for use in an image projection apparatus illuminating an image display panel forming an image in accordance with a modulating signal with illumination light from a light source. The projection optical system includes first and second optical systems arranged along an optical path defining an upstream-downstream direction in the order described from upstream to downstream on the downstream side of the image display panel. The first optical system includes at least one dioptric system and has positive power. The second optical system includes at least one reflecting surface having power and has positive power. The image formed by the image display panel is formed as an intermediate image in the optical path, and the intermediate image is magnified and projected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.