| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lighting device using a semiconductor light-emitting element capable of attaining both brightness and light utilizing efficiency, and a well-lighted projection type display device capable of integrally enhancing the light utilizing efficiency including a display system by the use of the lighting device. <P>SOLUTION: The lighting device comprises an optical converging point 11, semiconductor light-emitting elements 4 arranged so that emitted light converges into the optical converging point 11, and a fluorescent body 5 arranged at the optical converging point 11 emitting visible light by converting a wave length of the excited light emitted from the semiconductor light-emitting element, wherein light from the fluorescent body is irradiated on an object to be irradiated. The total surface area of the fluorescent body 5 in the visible light emitting direction is set smaller than the total excited light emitting surface area of the semiconductor light-emitting element. By the above, the problem of insufficiency of the light quantity as a lighting device caused by the inadequate light quantity of the semiconductor light-emitting element is coped with by using a number of light-emitting elements or by increasing the area thereof, whereby a problem that, while the illumination light itself gets brighter by the measure, an area of the light source is increased and utilization efficiency of the illumination light including that of the display system is decreased is solved. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
