METHOD FOR PRODUCING A METAL RADIO-FREQUENCY SMART CARD HAVING IMPROVED PERMITTIVITY WITH EXTENDED PERFORATIONS

摘要

The invention concerns a method for producing a metal insert for a radio-frequency smart card, the method comprising the steps of forming or providing an assembly (1) comprising an insulating substrate (2) carrying: - at least one antenna coil (3) with two terminal ends (4, 5) or a coupling interface, resting on the substrate, - a metal plate (7) comprising radio-frequency permittivity perforations and a recess (8) for receiving a radio-frequency chip module, passing through the plate and arranged respectively opposite the antenna coil and its ends. The method is characterised in that it comprises forming, in the plate, at least one slot-shaped perforation (19, 21) or at least two slot-shaped perforations (19, 21) each extending between perforations situated on coil portions (L3, L4) arranged symmetrically or diametrically opposite each other in the coils or separated by a portion of the coupling surface (6) situated inside the coils. The invention also relates to a card corresponding to that obtained by the method.