Ghost-free automotive head-up display employing a wedged windshield
US5013134A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 1989 |
| Grant date | May 7, 1991 |
| Priority date | — |
| Expiry date | Sep 28, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2027/0194
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A substantially ghost-free head-up display for a vehicle such as an automobile is disclosed. A head-up display unit projects the image beam toward the vehicle windshield for reflection back toward the viewer's eye. The windshield is slightly tapered so that the reflected images from the outside and inside surfaces of the windshield are reflected at slightly different angles, chosen so that the images substantially overlap at the viewer's eye. Use of a properly selected taper results in substantially ghost-free operation. The taper can be achieved by sandwiching a tapered layer of transparent material such as polyvinylbutyral between two windshield singlets.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.