Key board switch unit with illumination
US4343975A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 1, 1980 |
| Grant date | Aug 10, 1982 |
| Priority date | — |
| Expiry date | Dec 1, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2223/034
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention provides a novel key board switch unit with illumination in the pushing areas, e.g. push buttons. Different from conventional ones, the pushing areas in the inventive unit are illuminated indirectly with the light emitted from a lamp positioned at a remote place not directly visible from above the pushing areas and, instead, an optical conductor member made of a transparent material is provided between the lamp and the pushing areas to be illuminated. The inventive key board switch unit can be very compactly designed despite the sufficiently high but not glaring intensity of illumination facilitating the operation of the switches even in a dark place.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.