Reflective polarizers having extended red band edge for controlled off axis color
US5808794A · kind A · utility
Inventors
Key dates
| Filing date | Jul 31, 1996 |
| Grant date | Sep 15, 1998 |
| Priority date | — |
| Expiry date | Jul 31, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/305
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Reflective polarizers, which transmit one polarization and reflect the other polarization, have an extended red band edge in the off-axis transmission spectrum to control off axis color (OAC) hue. To control the OAC hue, the red band edge of the off-axis transmission spectrum, or OAC spectrum, is shifted beyond the boundary for red light, or to at least 600 nm. Even more preferably, the OAC spectrum is extended further into the red than any red emission peak of an associated lamp providing light into a system in which the reflective polarizer is used. The concept applies equally well to any type of reflective polarizer, such as multilayer reflective polarizers, cholesteric reflective polarizers, and the like. The resulting reflective polarizers are very useful for many different applications, such as liquid crystal displays.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.