Color filtering device

A color filtering device, suitable for being used in a projection apparatus, the projection apparatus comprising a lamp module, a light integration rod, and a light valve, the lamp module being capable of providing an illumination beam, the light integration rod being disposed on a transmission path of the illumination beam and having a light input end and a light output end, and the light valve being disposed on a transmission path of the illumination beam and being capable of converting the illumination beam into an image beam, the color filtering device comprising:

• a color filter, having a plurality of filtering parts and a plurality of light shielding parts alternately arranged thereon, the color filter being disposed on the transmission path of the illumination beam and between the light integration rod and the light valve, and the color filter being capable of being moved or rotated, so as to make each of the filtering parts face the light output end of the light integration rod in turn;
• a plurality of polarization beam splitting units, respectively disposed in front of the filtering parts, each of the polarization beam splitting units making an angle with a corresponding filtering part;
• and
• a plurality of reflecting units, respectively disposed in front of the light shielding parts, each of the reflecting units making an angle with a corresponding light shielding part;
• a plurality of wave plates, substantially parallel to the filtering parts respectively, each of the polarization beam splitting units being disposed between a pair of a corresponding wave plate and a corresponding filtering part.