Patent · US Expired

Low power drain illuminated sign

US5448843A · kind A · utility

10Cited by
5References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 12, 1993
Grant dateSep 12, 1995
Priority date
Expiry dateOct 12, 2013

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 which are formed by having the perimeter walls of each cavity conform precisely to each individual area of the sign desiring illumination, typically alphabetic characters and the background area they create. The bottom walls of these cavities will project towards the viewers eye parabolically. The midpoint of the cavity, when viewed in cross section, is to be slightly less in height than that of the cavity-defining perimeter walls. The perimeter walls have point source lights such as light emitting diodes (LEDs) distributed along their surface. These cavities may be filled in with transparent substance, fully encapsulating the LEDs thereby eliminating any reflective air space and facilitating light diffusion. The light sources may be provided with circuitry allowing unique powering to each of the individual cavities, resulting in the possibility of a variety of different display effects.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.