Light-guiding method of light-guiding plate and key pad assembly using the light-guiding plate
US7534001B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 7, 2007 |
| Grant date | May 19, 2009 |
| Priority date | — |
| Expiry date | Apr 25, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2219/062
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A key pad assembly includes a printed circuit board, a first elastic layer, a second elastic layer, a light-shielding layer, a keycap group, a light-emitting element and a light-shielding piece. The second elastic layer has a light-guiding plate thereon. The light-guiding plate has a chain-like light-shielding structure. The light-shielding structure is constituted of a plurality of penetrating holes with neighboring ones arranged alternatively and divides the light-guiding plate into two light-guiding sections. When the lights with different colors are introduced from the outside of the two light-guiding sections into the light-guiding plate, and the light of either light-guiding section passes through the light-shielding structure, the intensity of the light passing through the penetrating hole is so reduced that it cannot achieve the other light-guiding section, thereby to avoid the mutual interference and mixing of the lights of the two light-guiding sections.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.