| 摘要 |
<p>PROBLEM TO BE SOLVED: To efficiently and uniformly irradiate an image forming means with illuminating light even in the case of a light source having a large light emitting part in an illumination optical device using a lens array plate and used for a projection display device. SOLUTION: A light guide array 17 where plural light guides 16 guiding light from the lens 13 of the 1st lens array plate 12 to the corresponding lens 15 of the 2nd lens array plate 14 are arranged is arranged between the 1st and the 2nd lens array plates 12 and 14. By such constitution, luminous flux lost after it is emitted from the 1st lens array plate 12 is effectively guided to the corresponding lens 15 of the array plate 14 by the light guide 16, whereby the losing of light when the light guide 16 does not exist is eliminated even in the case of a lamp 10 having the large light emitting part, that is, having long arc length, and the illumination optical device whose light utilization efficiency is high is obtained.</p> |
