Laminar light guide
US4323951A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 16, 1980 |
| Grant date | Apr 6, 1982 |
| Priority date | — |
| Expiry date | Jun 16, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG12B11/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention relates to laminar light guides which are particularly suitable for providing illumination from one or more light sources to a plurality of instruments and other display devices as in a vehicle instrument panel. The guide makes efficient use of the light available from the light sources. The guide comprises a transparent lamina (1,2,3) having at least one integrally formed light input socket (4) for receiving a light source (14). The socket (4) is formed with lens means (13) and reflecting means (15) for directing light from the source into the plane of the lamina where it is internally reflected until encountering extracting means including roughened surfaces (6,7,8,9) for reflecting light diffusely out of the plane of the lamina or conical apertures (5) for reflecting light into a beam transverse to the plane of the lamina. The light is extracted to illuminate display characters (16) or areas in an otherwise opaque screen (17), or to direct light into pointers of instruments, for example clocks, speedometers etc.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.