In a color wheel comprising plurality of color filter segments, one of the filter segments consists of a sector portion, and a circular core portion which is formed intergrally at the inner circumferential area of the sector portion, and which is located at the center of the wheel assembled. The inner circumferences of the remaining filter segments are fitted directly to the outer perimeter of the circular core portion of the one segment, whereby the geometric accuracy of the color wheel can be achieved. Also, the alignment process of the filter segments for preventing the color wheel from generating vibrations and noises at the time of spinning at high speed can be simplified or even eliminated thus preventing the number of manufacturing processes from increasing.