A drive, primarily for an optical light forming device, which light forming device can be used in a projector, which light forming device comprises an at least partly open area for light, where at least two light forming devices cooperate in a light path for forming the light, which light forming devices are rotated around a common axis in and out of the light path. To achieve opposite synchronous movement of light forming means, the light forming devices are rotated equal in opposite directions around the common axis by a common motor. Hereby, it can be achieved that the two light forming devices are rotated synchronously, but opposite in relation to each other. The opposite synchronous movement is very important if the light fainting devices are part of a modern computer controlled projector using step motors.