PROJECTION DEVICE

PURPOSE:To prevent the loss of light quantity and to improve the projection characteristic of a picture by separating/synthesizing an illuminating optical system and a projection optical system utilizing a void region on the optical path of an illumination light beam. CONSTITUTION:A light source l, an ellipsoid mirror 2 and a condenser lens 3 are provided in an illuminating optical system and an optical path selecting member 4 is provided on the optical path of the illuminating optical system. A light beam reflected by a light bulb 6 is spacially modulated in conformity with picture information, a scattered reflection beam and a normal reflection beam are generated and a condenser lens 5 converges the normal reflection beam from the light bulb 6 in the void region 10. The reflection part 4a of the optical path selecting member 4 is provided in the void region 10 and the reflection part 4a is arranged so as to make the inclination of 45 deg. to the light bulb 6. Consequently, the reflected beam converged by the condenser lens 5 is converged on the reflection part 4a, reflected, introduced to a projection lens 7 while its optical path is bent by 90 deg. and forms a picture on a screen 8.