Optical system for use in an image projector
US6188524A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 4, 1999 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | Feb 4, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/7441
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A projector optical system has a reflection-type display panel, an illumination optical system for illuminating the reflection-type display panel, and a projection optical system for projecting the images displayed on the reflection-type display panel onto a screen. The projection optical system has, from the screen side, a front lens unit and a rear lens unit. A light-deriving means for directing illumination light toward the reflection-type display panel is disposed between the front and rear lens units. Additionally, the following condition is fulfilled: EQU 0.2<.phi.F/.phi.<0.9 where .phi.F represents the optical power of the front lens unit of the projection optical system, and .phi. represents the optical power of the entire projection optical system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.