Projection-type video-image-displaying device

A projection-type video-image-displaying device comprising:

• a light source which radiates white light;
• a light-collecting optical element which collects light from the light source and emits the light;
• a rotary color filter which is disposed near an emitting surface of the light-collecting optical element and has a plurality of types of filters for selectively transmitting or reflecting light of a specific color in a predetermined order from white light which is emitted from the emitting surface of the light-collecting optical element;
• a light modulation element which has a plurality of pixels and which modulates incident light in accordance with an image signal and performs an image display;
• an illumination optical element which collects emitted light from the rotary color filter and forms illumination light for projecting the emitted light onto the light modulation element;
• a projection lens which projects an image formed by the light modulation element;
• and
• a control device which controls a rotation of the rotary color filter to synchronize with the image display by the light modulation element, wherein
• the rotary color filter forms, on a part thereof, a light-emitting surface using light from the emitting surface of the light-collecting optical element, and
• the illumination optical element is disposed so as to have a substantially conjugate relationship with the light-emitting surface on the rotary color filter;
• whereby the emitting surface of the light-collecting optical element is disposed so as to be slightly inclined at an angle with respect to a surface of the rotary color filter, and the slight inclination angle is set in a range of 1 to 10 degrees.