DLP projectors use a high-speed, rotating colour wheel to create an image, the projector reflects light off of thousands of micromirrors (one mirror per pixel). Portable DLP projectors can only display one colour at a time so moving images can suffer from an annoying rainbow patterning on the screen. In most single-chip DLP projectors, a clear (white) panel is included in the colour wheel along with red, green, and blue in order to boost brightest. This can reduce colour saturation, making the DLP picture appear not quite as rich and vibrant.