Projection display having an angle-selective coating for enhanced image contrast, and method for enhancing image contrast
US6992830B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 2004 |
| Grant date | Jan 31, 2006 |
| Priority date | — |
| Expiry date | Apr 22, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/14
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A projection display includes a light source, a spatial light modulator that receives a light from the light source, and an angle-selective coating disposed to receive the light beam from the spatial light modulator. The angle-selective coating is oriented at a non-zero inclination angle to the light beam. The angle-selective coating has a higher transmission for light that is incident upon the angle-selective coating at an incidence angle within an acceptance-angle deviation from a design incidence angle, than for light that is incident upon the angle-selective coating at an incidence angle greater than the acceptance-angle deviation from the design incidence angle. The projection display preferably includes a TIR (total internal reflection) prism disposed to reflect a light beam from the light source to the spatial light modulator, and to receive the light beam from the spatial light modulator. The angle-selective coating is preferably buried within the TIR prism.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.