Rear projection optical system
US6779897B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 2002 |
| Grant date | Aug 24, 2004 |
| Priority date | — |
| Expiry date | May 28, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/005
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An oblique projection optical system for leading rays of light from a display surface on which an image is displayed to a projection surface in such a way that the ray of light from the center of the display surface is obliquely incident on the projection surface in order to project a magnified image of the image displayed on the display surface onto the projection surface includes a plurality of reflecting surfaces having a power. At least two of the reflecting surfaces have a free-form curved surface, and, of all the reflecting surfaces, the one closest to the projection surface has a negative power and at least one of the other has a positive power. Alternatively, in a rear projection optical system having a projection optical system for projecting an image displayed on a panel display surface onto a screen surface, the projection optical system includes at least four curved-surface reflecting mirrors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.