| 摘要 |
PROBLEM TO BE SOLVED: To provide an illumination system in which generated heat is reduced and which is compact and produced at low cost as the illumination system outputting linearly polarized light, and further a compact and high-performance display device using the illumination system. SOLUTION: Natural light emitted from a lamp 1 is condensed by a parabolic reflector and made incident on cholesteric liquid crystal 2, where only circularly polarized light in one rotating direction is transmitted, and the reversely rotated circularly polarized light is reflected. The transmitted light through the liquid crystal 2 is changed to the linearly polarized light by a &Igr;/4 phase plate 3, and made incident on an incident polarizing plate 4 whose polarizing direction is made the same. The loss of the light is only the absorbed one by the material. The transmitted light through the polarizing plate 4 is projected to a screen 7 through an image forming liquid crystal panel 5, an emitting polarizing plate 4' and a projection lens 6. It is conceivable to constitute a polarized light modulation element of cholesteric liquid crystal, a phase plate, a liquid crystal panel and an emitting polarizing plate. |
