Patent · US Expired

Optical system for illuminating a spatial light modulator

US5900981A · kind A · utility

38Cited by
8References
33Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 15, 1997
Grant dateMay 4, 1999
Priority date
Expiry dateApr 15, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/7416
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A novel optical system operative to transfer, with high efficiency, optical power from a line source, such as a LDB, built from a plurality of individual light sources with different angular distribution in two orthogonal axis into a rectangular area with a particular aspect ratio and two different numerical apertures. The near field pattern of a LDB is imaged onto the plane of an SLM. The system utilizes light generated from an LDB having a plurality of individual light sources to illuminate a microlens array. The microlens array, consisting of a plurality of microlenses, functions to collimate the light from the LDB in the slow axis. An optical element adjacent the microlens array refracts the light in the fast axis. In the slow axis, the light from the microlens array is incident upon an optical element which focuses the light onto the SLM plane such that the light from each point light source illuminates the entire active pixel area of the SLM. An additional optical element focuses the light in the fast axis to generate the required spot image. The optical system of the present invention utilizes natural aberrations and/or artificial aberrations to decrease the sensitivity of t…

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