Patent ID: 7495655

Claim:
A control device for a display panel, comprising: a) a mobile control unit having an emitter configured to emit a diffuse light beam; wherein the diffuse light beam projects a light field in an area of a plane, and wherein the light field has a pattern, b) an electronic processing unit configured to data-generate a graphic control marker that is freely positioned in a first graphical user interface of the display panel; c) a display unit configured to display a second graphical user interface and the graphic control marker; and d) an optical receiving sensor configured to convert movement directions of the pattern of the light field of the diffuse light beam of the mobile control unit into a control signal, wherein, in the processing unit, the control signal effects tracking of the graphical control marker on the display panel in accordance with the movement directions of the diffuse light beam, wherein the pattern of the light field projected by the diffuse light beam is inhomogeneous.