Apparatus for head up display comprising a parabolic reflective mirror
US5504622A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1994 |
| Grant date | Apr 2, 1996 |
| Priority date | — |
| Expiry date | Mar 17, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2027/0129
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides an apparatus for a head up display for the use of a motor vehicle, which can make a presentation of an image information in a remote place and which can remove a height-wise positional displacement of a double image and distortion of the double image caused by the curved shape of a vehicle front glass to the extent possible. In the apparatus for a head up display for the use of a motor vehicle according to the present invention, a projector (3) has a middle mirror (6) for reflecting an image information (9) such as characters or marks toward a reflective face. The middle mirror (6) includes a portion (18) of the parabolic reflective face which is located away from a main axis of a parabolic mirror. The portion (18) of the parabolic reflective face includes a first curved surface having a small curvature, corresponding to that portion of a vehicle front glass (2) which has a large curvature, and a second curved surface having a large curvature, corresponding t that portion of the vehicle front glass (2) which has a small curvature, so that distortion of the image information due to difference in curvature of the vehicle front glass (2) is corrected and…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.