Optical mouse
Optical mouse is hand held pointing device that uses light-emitting diode (LED) and photodiodes to detect movement rather than the traditional mouse ball and electromechanical transducer.
Modern optical mouse, work by using an optoelectronic sensor to take successive pictures of the surface on which the mouse operates. Most of these mouse use LEDs to illuminate the surface that is being tracked. Optical mouse do not normally require maintenance other than removing debris that might collect under the light-emitter and optical mouse last longer due to having no moving parts.