Patent · US Expired

Light diffusing apparatus with U-shaped light guide

US5581683A · kind A · utility

66Cited by
10References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 9, 1995
Grant dateDec 3, 1996
Priority date
Expiry dateFeb 9, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S385/901
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A light diffusing apparatus, which may be used as an elongate visual indicator in telephone sets, video cassette recorders etc, provides very even illumination (i.e., evenly diffused light without any discernible bright spots) when illuminated by spot light from one or two light emitting diodes. The apparatus includes a light guide having a light path of sufficient length to disperse the spot light from the emitting diodes. The dispersed light from the light guide then passes through a light diffuser. The light output end of the light guide and the light input surface of the light diffuser have uniform texture surfaces to further diffuse the dispersed light. The light diffuser may include diffusing particles. Very even illumination without any discernible bright spots is provided.

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