| 摘要 |
PURPOSE:To prevent color shading from occurring when a condenser lens is disposed in front of a liquid crystal panel by eliminating an unnecessary spectrum from a light source from an optical system with the aid of the combination of the characteristics of a set of dichroic mirrors for separating and for composing. CONSTITUTION:The unnecessary spectrum the light source 1 is eliminated from the optical system by the combination of the characteristics of a set of dichroic mirrors for separating and for composing 3, 4, 12 and 14. For example, only a green color spectrum 6 between the green color spectrum G and the unnecessary spectrum N transmitted through the condensor lens 8 and the liquid crystal panel for G 9 is reflected on a second dichroic mirror for G 12 having the same characteristic as a conventional one, composed with a blue color spectrum B and supplied to the dichroic mirror for R 14. Then, the unnecessary spectrum N is transmitted as it is and eliminated from the optical system. Therefore, even when the characteristic of the dichroic mirror is shifted by the uncollimated beam of light, the hue unevenness of the light after it is composed is reduced. Thus, even when a projecting lens is miniaturized by disposing the condenser lenses 6, 8 and 10 in front of the liquid crystal panel, an image having the little color shading is obtained. |
