Compact keypad system and method
US5612690A · kind A · utility
Inventor
Key dates
| Filing date | Jun 3, 1993 |
| Grant date | Mar 18, 1997 |
| Priority date | — |
| Expiry date | Jun 3, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2223/0345
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a key pad key cap symbols are placed at the interstices between key caps as well as at their centers. The key pad electronics are designed to register simultaneously actuated key caps at an interstice as an input uniquely associated with the symbol locate at the interstice. The linear dimension of a row of key caps are approximately one-half that of a conventional key cap requiring approximately two key caps to form a linear dimension sizable enough to comfortably accommodate the tip of an adult finger. Additionally, the symbols located at the centers of key caps are elevated slightly, allowing unimpeded and ergonomic access to individual keys as well as the interstices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.