Patent · US Expired

Optical device for modifying the angular and spatial distribution of illuminating energy

US6123436A · kind A · utility

40Cited by
10References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 5, 1997
Grant dateSep 26, 2000
Priority date
Expiry dateAug 5, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B5/10
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A deconcentrating optic has an input aperture positioned near a point of minimum focus of a reflector, and has an output aperture which is larger than the input aperture. An inner surface connects the two apertures of the optic. The surface is reflective to visible light, and is shaped to decrease the angles of incident light rays from the reflector so that an emerging light beam is bounded by a cone the angle of which is less than or equal to the acceptance cone of a projection lens. The size and shape of the output beam is such that the object lying in the projection plane of the lens is fully illuminated but not overfilled. The inner surface of the reflecting optic may be selectively perturbed so that the object plane of the projection lens is uniformly illuminated. The general shape of the reflecting optic's inner surface may be parabolic, elliptical, hyperbolic, circular, conical, or combinations of these shapes. The perturbations of the inner surface may be protrusions on or indentations in the inner surface, and may have shapes that are circular, planar, triangular, parabolic, random, or any other shape. A solid deconcentrating optic is transparent throughout, having a refle…

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