Patent ID: 7326913

Claim:
A control device ( 20 ) particularly for controlling the movements of a cursor on a screen of an electronic apparatus, comprising: an actuation member ( 30 ) in the form of a spherical ball with a detection surface ( 31 ) capable of being manipulated by a user; a ball casing ( 22 ) which forms a concave face ( 42 ) that surrounds at least a portion of the ball ( 30 ); elements ( 56 ) for guiding the ball ( 30 ) in rotation, so that the ball rotates about its centre (C); at least a first detection light source (LS 1 ) to emit at least one incident detection light beam (EL 1 ) towards the ball ( 30 ); and means forming image sensors ( 126 ) that receive the light (RL 1 ) originating from the zone of the ball ( 30 ) lit by the incident detection beam (EL 1 ); characterized in that: the first light source (LS 1 ) emits an invisible light (EL 1 ); and the device comprises at least a second light source (LS 2 ), distinct from the first light source (LS 1 ), for illuminating the ball ( 30 ) which emits a visible illumination light (EL 2 ) towards the ball ( 30 ).