Polarized light separation device, method of fabricating the same and projection display apparatus using the polarized light separation device
US6394607B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 1997 |
| Grant date | May 28, 2002 |
| Priority date | — |
| Expiry date | Nov 12, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/7441
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The invention provides a plate-shaped polarized light separation device that has a repetitive structure of polarized light separation film surfaces and reflective film surfaces arranged alternately at a fine pitch, along with a projection display apparatus that uses this polarized light separation device. In the process of manufacturing the polarized light separation device, first a glass block is formed by alternately pasting together plate glass with a polarized light separation film made up of a multi-layer thin film of inorganic material upon its surface and plate glass with a reflecting film upon its surface, and this glass block is cut obliquely to the pasted surfaces. A projection that is usable at the time of the positioning of the polarization beam splitter may be provided on at least one side of this plate-shaped block that is thus cut out. By providing a &lgr;/2 phase plate on portions of the light exit surface of this polarized light separation device, one obtains a polarized light separation device that takes light from a light source and emits it as a light flux having only one direction of polarization, either S-polarized light or P-polarized light. Such a polarized …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.