Polarized light illumination device and projection display device
US6042234A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 17, 1999 |
| Grant date | Mar 28, 2000 |
| Priority date | — |
| Expiry date | Feb 17, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3167
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A polarized light illumination device that is able to utilize both polarized light components by using a plurality of light sources without increasing the illumination angle, and a projection display device that is able to project a considerably bright projection image are provided. In a polarized light illumination device, randomly polarized light emitted from first and second light sources is directionally separated into two types of polarized light by a polarized light separating and synthesizing optical element, secondary light-source images, which are offset in the x direction, are formed, and then, the direction of polarization is aligned. In this case, at least two of first to third light-collecting mirror plates are shifted in parallel from about the center axis of the polarized light separating and synthesizing optical element so that secondary light-source images of s-polarized light in emitting light from the first and second light sources overlap each other, and so that secondary light-source images of p-polarized light overlap each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.