Low power drain illuminated sign
US5697175A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Dec 16, 1997 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S362/812
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An illuminated sign apparatus comprised of a reflector with dedicated cavities. Each letter and, optionally, background area, comprises a shaped cavity, illuminated indirectly by a plurality of near-point sources such as light-emitting diodes located in the center of the cavity, either on a separate perpendicular circuit board or on a central projection formed in the bottom of the cavity, with the light emitted by the sources pointed outwards. In another embodiment, the letter cavities and background are illuminated by parallel boards along the top, bottom, and (optionally) middle of the letter cavities, with the light sources directed along the axes of the letter strokes. In another embodiment, the light sources in the center of the cavity are electroluminescent and ultraviolet emitting, and the cavity can be coated with a UV activated flourescent coating which is activated by the EL light source. The light is evenly reflected upward toward the viewer, giving the illusion of a solid letter or background. The cavities may be filled with a transparent substance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.