Patent · US Expired

Projection system having low astigmatism

US6672721B2 · kind B2 · utility

19Cited by
12References
102Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 11, 2001
Grant dateJan 6, 2004
Priority date
Expiry dateJun 11, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/3167
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Generally, the present invention relates to an apparatus for reducing astigmatism in a projection system that is particularly well suited to reducing astigmatism in LCD projection systems. A projection system includes a light source to generate light, conditioning optics to condition the light from the light source and an imaging core to impose on image on conditioned light from the conditioning optics to form image light. The imaging core includes a polarizing beamsplitter and at least one imager, and at least one element in the imaging core is adapted to reduce astigmatism in the image light. The astigmatism may arise in the polarizing beamsplitter. A projection lens system projects the astigmatism-reduced image light from the imaging core.

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