Optical-mechanical roller with ratchet

A pointing device, such as a mouse, track ball or joystick, having a roller. The roller itself has either a plurality of slits or reflective strips for optical detection. A photoemitter and photodetector are positioned to detect rotation of the roller. Thus, the present invention eliminates the need for coupling to a separate optical encoder. The roller can be depressed to cause the actuation of a microswitch. In a preferred embodiment, the photoemitter and photodetector are aligned along a vertical axis, such that the position information is not affected by the vertical depressing of the roller.