Abstract: A reader arrangement 22 for an electronic identification system includes a plurality of reader heads 22.1 to 22.4 for energizing transponders 28.1 to 28.n to be read, and a controller 29 therefor. The controller 29 switches activation of the reader heads in a multi-phase sequential pattern including a first phase for activating a first set 22.1 and 22.3 of the reader heads and at least one further phase for activating a further set 22.2 and 22.4 of the reader heads. The switching is such that a complete cycle plus at least the first phase of a subsequent cycle is completed within a time period not longer than a reset period of the transponders. The reset period is the period between removal of an energizing signal from a transponder and the transponder re-entering a normal operational mode.

Abstract: A card containing a programmable microchip having a memory for storing a color identification photograph. A color identification image is digitally compressed from a photograph by a novel method which makes practical the use of a relatively small amount of memory for the storage of the image.