Illumination system and projector
US6513953B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 22, 2000 |
| Grant date | Feb 4, 2003 |
| Priority date | — |
| Expiry date | Feb 22, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B3/0068
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An illumination system includes a light source that emits unpolarized light, a power variation optical relay system that changes the size of a light beam emitted by the light source, a superposition optical system that effects illumination of an illumination region by an incident light beam, a polarization conversion system that is provided at a selected position along a light path from the incident surface of the power variation optical relay system to the exit surface of the superposition optical system to convert an incident beam of unpolarized light to a light beam having linearly polarized components with one type of polarization direction and emits the converted light beam. The size of a light beam entering the polarization conversion system in a prescribed direction is reduced by the power variation optical relay system. The illumination system includes an integrator optical system and polarization conversion system that uses a light source lamp with a higher output than a conventional lamp, and allows the light output to be increased without decreasing the utilization efficiency of the illumination system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.