G06K 7/10128

Methods or arrangements for sensing record carriers, {e.g. for reading patterns} by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation {sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the sensing being preceded by at least one preliminary step the step consisting of detection of the presence of one or more record carriers in the vicinity of the interrogation device}