Patent · US Expired

Rear projection screen with uniformity of luminance

US6292294A · kind A · utility

12Cited by
13References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 22, 1999
Grant dateSep 18, 2001
Priority date
Expiry dateFeb 22, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B21/625
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A rear projection screen including a Fresnel lens sheet arranged on the projection side, and a lenticular lens sheet arranged on the observation side. The Fresnel lens sheet has a lenticular lens for vertical diffusion on its light-entering side. The lenticular lens for vertical diffusion containing a plurality of convex lenses that extend horizontally, and these plural convex lenses are arranged with a constant pitch. Further, the diffusion angle of the lenticular lens for vertical diffusion continuously increases, and, at the same time, the direction of diffusion is gradually inclined to the central part as the distance from the central part toward each of the edges on the screen surface increases. The diffusion properties (the angle and direction of diffusion) of the lenticular lens thus continuously vary between the central part and the edges of the screen surface.

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