An ID recognition system is described that uses optical beacons and a high-speed image sensor. The ID sensor captures a scene like an ordinary camera and recognizes the ID of a beacon emitted over a long distance. The ID recognition system has three features. The system is robust to changes in the optical environment, e.g. complete darkness, spotlights, and sunlight. It can recognize up to 255 multiple optical beacons simultaneously. Furthermore, it can recognize beacons even over a long distance, e.g. 40 m indoors and 20 m outdoors. Implementation and evaluation of this ID recognition system showed that a mobile augmented reality system can be achieved by combining this ID recognition system with a PDA and a wireless network.