Contactless card standards encompass a variety of types as embodied in International Standards

• ISO/IEC 10536 (Close-coupled cards)
• ISO/IEC 14443 (Proximity cards)
• ISO/IEC 15693 (Vicinity cards).

These device types are intended, respectively, for operation when very near, nearby and at a longer distance from associated coupling
devices.

ISO/IEC 15693

ISO/IEC 15693 defines the technology-specific requirements for identification cards conforming to ISO/IEC 7810 and thin flexible cards conforming to ISO/IEC 15457-1 and the use of such cards to facilitate international interchange.

However, it also recognizes that the technology offers the possibility that vicinity objects may be provided in forms other than that of the international standard card formats.

Furthermore, it does not preclude the incorporation of other standard technologies on the card. ISO/IEC 15693 accommodates the operation of Vicinity cards in the presence of other contactless cards conforming to ISO/IEC 10536 and ISO/IEC 14443 standards.

As the vicinity cards have to operate at a greater distance, the necessary magnetic field is less (0.15 to 5 A/m) than that for a proximity card (1.5 to 7.5 A/m).