Patent · US Expired

Indirect luminaire having a secondary source induced low brightness lens element

US4939627A · kind A · utility

56Cited by
3References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 14, 1989
Grant dateJul 3, 1990
Priority date
Expiry dateSep 14, 2009

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF21Y2103/00
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An indirect lighting system having a generally visible light transmissive element, such as a prismatic lens element or a diffuser strip, which modifies the direction of the light incident thereon from a secondary light source. The lighting system has a primary light source and structural means for positioning the primary light source proximate a reflective surface which reflects light back toward the light transmissive element and which thereby acts as a secondary source of light for illuminating this element. A light foil means is disposed between the primary light source and light transmissive element for substantially blocking direct transmission of light to the latter from the former. The light foil means, by keeping primary source light from directly striking the light transmissive element, forces the observable brightness in this element to be induced substantially entirely by the reflected light from the secondary source.

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