Illuminating optical system and projector utilizing the same
US5749642A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1997 |
| Grant date | May 12, 1998 |
| Priority date | — |
| Expiry date | Mar 17, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/2066
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
This invention provides a projector capable of effectively utilizing the light from the light source and significantly reducing the light illuminating the outside of the area to be illuminated, thereby attaining an excellent efficiency of light utilization. In the illuminating system of the present invention provided with a light source and a reflector, there is further provided a circular reflector of a spherical surface, for returning the light, which emerges from the light source to the outside of the area to be illuminated, without being reflected on the reflector, to the light source. Also there is provided a flat mirror or a substantially spherical sub reflector for returning the light, which proceeds to the outside of the area to be illuminated, after being reflected on the reflector, to the light source. The sub reflector may be provided in the vicinity of the light source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.