The digital signal processor in an optical mouse receives images captured by the camera. Once all images are received, it compares the pictures and looks for differences between them. Even the minutest differences can easi\y be picked up. This helps the processor determine the exact distance and speed covered by the mouse. The coordinates are then measured and sent to the computer. As a result
the mouse pointer moves to a particular location on the screen according to the movement of the mouse.



The digital signal processor which was placed in the first optical mouse created by Microsoft could take in 18 million instructions per second, thus drastically reducing jerks caused by mouse movements on the screen.