Patent · US Expired

Optical system for use in an image projector

US6091550A · kind A · utility

9Cited by
2References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 26, 1999
Grant dateJul 18, 2000
Priority date
Expiry dateFeb 26, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B13/04
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A projector optical system has a reflection-type display panel, an illumination optical system for illuminating the reflection-type display panel, a projection optical system for projecting the images displayed on the reflection-type display panel onto a projected surface, and a light-deriving means for directing illumination light toward the reflection-type display panel. The projection optical system has, from the projected-surface side, a front lens unit and a rear lens unit. The light-deriving means is disposed between the front and rear lens units. Additionally, the following condition is fulfilled: EQU -1.5<.phi.F/.phi.<-0.1 where .phi.F represents the optical power of the front lens unit of the projection optical system, and .phi. represents the optical power of the entire projection optical system.

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