Display apparatus
US5894298A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 14, 1997 |
| Grant date | Apr 13, 1999 |
| Priority date | — |
| Expiry date | Mar 14, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D30/70
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An alphanumeric, and graphics liquid crystal display having utility in portable devices used in communications, measurement, and data display systems generally, is disclosed in the environment of a wireless telephone handset. The display includes a transparent viewing screen having a reflective substrate adapted to display thereon transitory opaque symbols in response to data signals received during a telephone call or generated at a keypad of the handset when a call is placed. Positioned under the substrate, an illumination screen has selectable elements which are illuminated in response to control signals generated in correspondence with the data signals. Being in registry with portions of the substrate on which the symbols are displayed, the selected elements of the illumination screen provide backlighting for viewing the symbols under low ambient light levels without illuminating the entire viewing screen, thereby conserving power in an on-board battery.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.