Projection type display apparatus
US5808795A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 1996 |
| Grant date | Sep 15, 1998 |
| Priority date | — |
| Expiry date | Mar 6, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3167
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A projection type display apparatus includes a spatial light modulator, a polarizing beam splitter formed of members of a transparent material, and a projection optical system. The polarizing beam splitter includes a dielectric multilayer film, and a first transparent material member and a second transparent material member sandwiching the dielectric multilayer film. Each of the first and second transparent material members is made of a transparent material with a refractive index of at least 1.8 and with an absolute value of the photoelastic constant being no more than 1.5.times.10.sup.-8 cm.sup.2 /N for light of wavelengths 0.4 .mu.m to 0.7 .mu.m, incident to the polarizing beam splitter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.