thumb|300px|a microsoft wireless optical mouse an optical computer mouse uses a light source, typically a light-emitting diode, and a light detector, such as an array of photodiodes or an image sensor, to detect movement relative to a surface. it is an alternative to the mechanical mouse, which uses moving parts to perform the same function. the earliest optical mice detected movement on pre-printed mousepad surfaces, whereas the modern optical mouse works on most opaque surfaces; it is usually unable to detect movement on  specular surfaces like glass, although some advanced models can function even on clear glass. laser diodes are also used for better resolution and precision. battery-powered wireless optical mice flash the led intermittently to save power, and only glow steadily when movement is detected. == early optical mice == thumb|xerox optical mouse chip early optical mice, first demonstrated by two independent inventors in 1980, came in two different varieties: some, such as those invented by steve kirsch of mit and mouse systems corporation, used an infrared led and a four-quadrant infrared sensor to detect grid lines printed with infrared absorbing ink on a special metallic surface. predictive algorithms in the cpu of the mouse calculated the speed and direction over the grid. thumb|the optical sensor from a microsoft wireless intellimouse explorer (v. 1.0a) others, invented by richard f. lyon and sold by xerox, used a 16-pixel visible-light image sensor with integrated motion detection on the same chip{{cite book | chapter = the optical mouse, and an architectural methodology for
American_inventions Computing_input_devices History_of_humanacomputer_interaction Pointing_devices Video_game_control_methods