Patent · US Expired

Solid state based illumination source for a projection display

US6325524A · kind A · utility

51Cited by
12References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 29, 1999
Grant dateDec 4, 2001
Priority date
Expiry dateJan 29, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S362/80
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A light source for generating light that is collected by an optical system that collects light leaving the light source within a predetermined acceptance angle relative to an axis defined in relation to the optical system. The light source includes a plurality of LEDs mounted on a reflecting base. Each of the LEDs generates light that leaves that LED via a top surface, a bottom surface, and one or more side surfaces of the LED. The reflecting base has a reflective surface in contact with the bottom surface of each of the LEDs. Light leaving the side surfaces of the LEDs is reflected into the acceptance angle of the optical system by a plurality of reflectors. In one embodiment of the invention, the reflectors include a plurality of reflecting facets for reflecting light leaving the side surfaces of the LEDs. The facets may be part of the reflective base or separate objects located between the LEDs. In another embodiment of the invention, the reflectors include scattering centers located between the LEDs.

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