Head-up display with polarized light source and wide-angle p-polarization reflective polarizer
US6952312B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 2002 |
| Grant date | Oct 4, 2005 |
| Priority date | — |
| Expiry date | Aug 30, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2027/012
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A head-up display includes a projection system and a window having a target area where a reflective polarizer is positioned to reflect light from the projection system to a viewing area. Light from the projection system is p-polarized and strikes exposed window surface(s) at an acute angle to reduce or eliminate multiple or “ghost” images. The acute angle is closely matched to a Brewster angle of the exposed window surface(s). The reflective polarizer includes a multilayer stack with refractive indices of individual layers chosen to reflect p-polarized light substantially more than s-polarized light over a wide angular range that includes the acute angle. The reflective polarizer also can reflect infrared light to reduce cabin heating from solar radiation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.