Abstract: A trackball includes a ball, a housing including a recess arranged to receive at least part of the ball and means for urging the ball, without physical or direct contact, to remain in the recess, wherein the surface of the recess is fully sealed to form an impenetrable barrier such that foreign substances are prevented from entering the interior of the housing. This arrangement may make the trackball more hygienic to use and easier to clean than conventional trackballs.

Abstract: 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.

Abstract: An electronic pointing cursor control device such as a trackball or mouse, comprising a first chamber adjoined to a second chamber, the chambers being separated by a fluid-tight wall comprising an optically permeable region; wherein the first chamber contains electronic components including optical detectors directed towards the optically permeable region and a ball protruding through an aperture provided in the second chamber, the detectors being operable in use to detect and generate electronic signals representative of motion of the ball. Also provided is an electronic pointing or cursor control device comprising a ball and optical detectors operable to detect and generate electronic signals representative of motion of the ball, wherein the detectors are mounted such that a radial line from the ball to the detectors forms a non-zero angle with a diametric line though the ball normal to the mounting plane of the device.