A color wheel includes lens structures, which are formed on a surface of a substrate opposite to a surface having filter sectors, and which have curved surfaces formed at their abutting ends and positioned along a boundary between adjacent filter sectors. Light impinging on an area of the substrate corresponding to the boundary is deflected due to one of the curved surfaces so as to be surely guided into one of the adjacent filter sectors and to be duly dispersed into a predetermined color, whereby light can be efficiently utilized.