| 摘要 |
PROBLEM TO BE SOLVED: To provide a small-sized two-light-source type polarized light source unit which can efficiently light a liquid crystal light valve etc. SOLUTION: In the two-light-source type polarized light source unit 1, pieces of luminous flux from light emission tubes 12 and 22 of light sources 14 and 24 are made into pieces L12 and L22 of parallel luminous flux by using reflectors 13 and 23 and concave lenses 15 and 25 and also compressed to the sizes of incidence opening parts 16b and 26b of a polarized light conversion optical system composed of a prism composite body. The polarized light conversion optical system is equipped with polarized light separating elements 16 and 26 composed of prism composite bodies and reflecting elements 17 and 27, which project four pieces of projection luminous flux in a state corresponding to a lighted area A; while polarized light converting elements 18 and 28 equalize the polarizing directions, the lighted area A is lighted. The projection light after polarized light conversion is made to correspond to the lighted area A, so a light source with high light use efficiency can be actualized. Further, the polarized light conversion optical system is constituted by using the prism composite bodies, so the polarized light source unit which is small-sized and compact can be actualized.
|
