Abstract: A lamp cartridge according to the present invention includes a lamp as a light source; a reflecting mirror for converging the light emitted from the lamp; and several side surfaces forming a case for covering the lamp, the reflecting mirror and for supporting the reflecting mirror. In the present invention, one of the surfaces forming the case where light is emitted out of the lamp cartridge and away from the reflecting mirror is provided with a hole having a diameter smaller than that of the end of the reflecting mirror. In addition, an optical axis of the hole is directly aligned with an optical axis of the end of the reflecting mirror where light is emitted out of the lamp cartridge. Further, a fan is provided on one of the side surfaces forming the lamp cartridge case. Outside air is introduced through the hole and into the interior of the lamp cartridge whereby heat generated by the lamp and the reflecting mirror is exhausted by the fan.

Abstract: An image display apparatus includes an arc lamp as a white-light source, an ellipsoidal mirror for collecting a light beam from the arc lamp, a color filter for producing sequentially three primary colors of light from the white-light beam, a condenser lens for transmitting a light beam transmitted through the color filter, and a single spherical mirror or non-spherical mirror for reflecting the light beam transmitted through the condenser lens. The image display apparatus further includes a digital micromirror device. This device receives the light beam reflected from the reflecting mirror and produces on and off states by varying the tilt of a micromirror of each of a number of two-dimensionally arrayed pixels to vary the angle of reflection of the light beam reflected therefrom. From there, a projection lens enlarges and projects the light beam reflected from a pixel.