US Patent 9189089 Pointing device with prevention of unintended input

A pointing device such as a scrolling device or trackball, including a ball formed at least partially from an electrically conductive material, and a PCB including a capacitive proximity sensor, wherein movement data representative of ball movement is communicated by a controller to an interface such as a monitor screen, and wherein an electrical switch is actuable in response to the proximity of the sensed object to the ball, such that when a user is not in contact with or in close proximity to the ball, movement data will not be communicated by the controller to the interface.