LEP electroluminescent backlit keypad for a cellular phone
US5971557A · kind A · utility
22Cited by
13References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 13, 1996 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Nov 13, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2219/037
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electroluminescent backlit device utilizing light-emitting polymers (LEP) is disclosed. A sandwich of LEP material and two electrical conductive materials are used to provide back lighting for a keypad or display. The electrical conductive layers are etched to form channels which provide current to and excite the LEP material to produce light at predetermined points. The etchings are directed around existing electrical contacts to facilitate normal operation of the underlying host system, such as a cellular telephone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.