Patent ID: 7436121
Filing Date: 2008-10-14
Classification: F21V,G03B,H01J

Abstract:
1. Light source device which comprises a discharge lamp having a silica glass discharge vessel containing a pair of opposed electrodes and at least 0.15 mg/mm a concave reflector which surrounds the discharge lamp and which reflects light emitted from the discharge lamp in a given direction through a light exit opening thereof; a power supply device which is adapted to selectively supply power to the discharge lamp of at least a first wattage and second wattage, the first wattage being higher than the second wattage; and a reflection heating means, said reflection heating means being adapted to return at least part of the light emitted by the discharge lamp in the direction of the discharge lamp during operation of the discharge lamp with the second lower wattage, and to return less light in the direction of the discharge lamp during operation of the discharge lamp at the higher first wattage than is returned during operation with the second wattage; wherein the reflection heating means is arranged movably in front of the light exit opening of the concave reflector.