Patent ID: 8190278

Claim:
A method of controlling a device, the method comprising acts of: arranging a plurality of retro-reflective marker elements having a plurality of shapes in unique positions relative to each other in a target area of an object to uniquely identify a device associated with the object; aiming a pointing device comprising a camera and a source of invisible light in the direction of at least one target area on an object associated with the device to be controlled, the plurality of retro-reflective marker elements reflecting at least a part of the invisible light emitted by the light source back to the pointing device; generating a first image of a target area aimed at by the pointing device when the light source is inactive; generating a second image of the target area aimed at by the pointing device whereby, at least during part of an exposure time for generating the second image, invisible light is emitted by the light source in the direction of pointing; extracting image data from at least one of the first target area image and the second target area image; processing the extracted image data to determine the presence of the retro-reflective marker elements; using information pertaining to the retro-reflective marker elements to identify the device to be controlled and/or to determine a control signal for the identified device, the extracted image data is extracted by means of a filter rule which is defined according to the device to be controlled.