Uniform illumination device for the dial of a display device
US5984485A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1998 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Jan 30, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04B19/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Illumination device for the dial (4) of a display device formed by a case (1) sealed by a crystal (8) arranged above the dial (4) and held by a fitting ring (9), said device including at least one light source (13, 33, 35, 43, 53) arranged in at least one recess arranged in at least one light guide (20, 30, 40, 50) positioned at the periphery of the dial (4), said guide having a polished internal surface (21) oriented towards the dial (4) and an external surface (22) held in a space delimited by the dial (4), the crystal (8) and the inner wall (10) of the fitting ring (9), characterised in that all or part of said external surface (22) of the guide is arranged to allow a progressive increase along the guide (20, 30, 40, 50) of the quantity of light diffused by said external wall gradually as one moves away from one of the light sources (13, 33, 35, 43, 53).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.