Patent · US Expired

Filter, illumination device and illumination method

US6554454B1 · kind B1 · utility

32Cited by
8References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 27, 2000
Grant dateApr 29, 2003
Priority date
Expiry dateJun 27, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N1/504
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

It is an object to provide an improved filter or illumination device. In order to achieve the above object, an illumination device is provided having multiple optical color filters wherein a first time period, required for at least one of the multiple optical color filters to pass across a light path, is different from a second time period, required for each of the other optical color filters to pass across the light path. According to another aspect of this invention, an illumination device has multiple optical color filters and an optical member wherein a boundary, which extends in a direction, is provided between one of the multiple optical color filters and another one of the multiple optical color filters, and the optical member includes an inlet for receiving light from the optical color filters, wherein the inlet extends in a first direction corresponding to the direction of the boundary when the boundary crosses the light path, for a greater distance than the inlet extends in a second direction.

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