Moving ball mouse:
In old computer systems, we have seen this mouse. Moving ball mouse has a rubber ball to make move over the plane surface to detect the X and Y direction motion. This was the traditional model of the computer mouse. This traditional mouse has a rubber ball inside them. Open one up and you can see the heavy ball clearly and the spring that keeps it in position.
Working of moving ball mouse:
When you move this mouse, the ball moves the rollers that move one or both of the wheels at once. One clever trick is hidden beside the wheels which contain light-generating and sensing units. Each wheel is made up of plastic spokes and, as it turns, the spokes repeatedly break a light beam. The more the wheel turns, the more times the beam is broken, and this beam break count is being used to precisely measure how far the wheel has turned and how far you have pushed the mouse. This calculation is being done by using onboard microchip circuitry and the processed signal sends to the computer system by using the cable. Software of computer system moves the mouse cursor on your display screen as per received signal.
Moving ball mouse internal structure