| 摘要 |
PURPOSE:To obtain parallel beams so as to be suitable for a liquid crystal projector, etc., in a light source device in which a lamp having plural luminescent points is used. CONSTITUTION:As to the light source device provided with the lamp 2 having plural luminescent points 4 and 5 inside a lamp tube 3, the lamp tube 3 is made to be an ellipse in which the plural luminescent points 4 and 5 are focal positions. The part of the lamp tube 3 of this ellipse, is a reflecting surface 6 reflecting light emitted to one luminescent point 4 which is one of the plural luminescent points 4 and 5 from the other luminescent point 5. Substantially, the device can be used as the lamp having the single luminescent point 4, furthermore, the parallel beams can be obtained by providing a parabolic reflector 9 whose focal position is the luminescent point 4. |
