Uniform illumination plate
US5128842A · kind A · utility
92Cited by
6References
7Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 3, 1991 |
| Grant date | Jul 7, 1992 |
| Priority date | — |
| Expiry date | Jun 3, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S200/47
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A laniform illumination plate comprising light emitters at one side thereof to irradiate the display section of the necessary keys with uniform illumination, a light-transmitting thin plate which has total reflection inside the plate thickness, the light emitters located in predetermined intervals, with sloped or curved concave reflecting sections formed on the bottom surface of the thin plate corresponding to the location of the keys, or strip shaped concave reflecting sections which run across the width of the thin plate, whereby the light is directed to the corresponding keys on the top surface of the thin plate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.