Patent ID: 7188973

Claim:
A light source device, comprising: a light-emitting tube including a light-emitting portion that generates a light beam by an electric discharge between electrodes and a pair of sealing portions respectively provided on both sides of the light-emitting portion; an ellipsoidal reflector having a substantially ellipsoidal reflecting surface and reflecting a light beam irradiated by the light-emitting tube after converging at a predetermined position; a sub-reflection mirror having a reflecting surface thereof being opposed to the reflecting surface of the ellipsoidal reflector and covering a front side of the light-emitting tube in the light-irradiation direction to reflect visible light of the light beam emitted by the light-emitting tube toward the ellipsoidal reflector and transmit the other light of the light beam; a transparent member provided in front of the ellipsoidal reflector in the light-irradiation direction to transmit the light beam; and a holder provided at a front end of the ellipsoidal reflector in the light-irradiation direction to hold an outer periphery of the transparent member, wherein the holder has a double structure with an absorber for absorbing the other light transmitted through the sub-reflection mirror provided on an inner side thereof.