PROJECTOR

PURPOSE:To improve projection characteristics by providing a projector with a light valve means, an illumination optical system and an imaging means and disposing a luminous flux section deforming element in the optical path of this illumination optical system. CONSTITUTION:The light of a light source 101 is condensed onto one point on the optical axis of a reflection mirror 102 and is made incident on a condenser lens 103. This light is made incident on a prism 104 which is the luminous flux section deforming element. Its optical path is bent by this prism and is expanded in the luminous flux diameter in the curving direction. The luminous flux for illumination from the prism 104 is emitted perpendicularly from the exit surface and its sectional shape is so adjusted as to be inscribed with the four corner parts of the image information display surface of the light valve 105 in its irradiation region. The magnification rate of the prism 104 is determined by a vertex phi1 and incident angle theta1. The luminous flux reflected by the light valve 105 is spatially modulated according to the image information of the image information display surface and is projected by an imaging lens 106 to form image.