A filter-free projector includes a light source unit to generate light beams with different colors and a color control module coupled to the light source unit for switching the light source unit to emit one color of light at a time. A digital mirror device panel having a plurality of mirror elements is provided so as to reflect light fed from the light source unit. A projection lens is positioned in the reflected light path from the digital mirror device panel to project the image. The switching-on time of independent lights in the light source unit can be overlapped or not overlapped.