Automotive display apparatus
US5172100A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 16, 1991 |
| Grant date | Dec 15, 1992 |
| Priority date | — |
| Expiry date | May 16, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2027/0154
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A prism is installed at a lower part of the windshield near the dashboard with a first surface of the prism directed toward a viewing point of a driver and a second surface held in contact with the inner side of the windshield. The first or second surface of the prism is made a reflecting surface. The third surface is formed with a dark paint layer. The apex of the prism where the first and second surfaces join is tilted toward the driver seat in such a manner that the second surface becomes a total reflection surface for light from the third surface with respect to the viewing point of a driver. The display image of an indicator installed in the dashboard below the prism is reflected either by the first or second reflecting surface of the prism toward the driver's viewing point. Light from the dark third surface of the prism is totally reflected by the second surface toward the driver to provide a dark background for the display, enhancing the display contrast. The prism, when viewed from outside the windshield, appears transparent thus maintaining a good external view of the windshield.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.