Smartcard with coupling frame and method of increasing activation distance of a transponder chip module

Patent metadata

Field	Value
Publication number	US-9798968-B2
Application number	US-201414492113-A
Country	US
Kind code	B2
Filing date	Sep 22, 2014
Priority date	Jan 18, 2013
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

A conductive coupling frame (CF) having two ends, forming an open loop having two ends or a discontinuous metal layer disposed surrounding and closely adjacent a transponder chip module (TCM, 610 ), and substantially coplanar with an antenna structure (AS, CES, LES) in the transponder chip module (TCM). A metal card body (MCB, CB) or a transaction card with a discontinuous metal layer having a slit (S) or a non-conductive strip (NCS, 1034 ) extending from a module opening (MO) to a periphery of the card body to function as a coupling frame (CF). The coupling frame (CF) may be thick enough to be non-transparent to RF at frequencies of interest. A switch (SW) may be provided to connect ends of the coupling frame (CF) across the slit (S, 630 ). A reinforcing structure (RS) may be provided to stabilize the coupling frame (CF) and card body (CB). The transponder chip module (TCM) may comprise an antenna structure which may be a laser-etched antenna structure (LES) or a chemical-etched antenna structure (CES), and may comprise and a non-perforated contact pad (CP) arrangement. A coupling frame (CF) may be incorporated onto the module tape (MT, CCT) for a transponder chip module (TCM).

First claim

What is claimed is:

1. A coupling frame (CF) for a smartcard (SC), comprising:
a metal layer (ML) having an opening (MO) for receiving a transponder chip module;
and a discontinuity, comprising a slit (S) or a non-conductive stripe (NCS), extending from the opening to a periphery of the metal layer.

2. The coupling frame of claim 1 , wherein:
the coupling frame is substantially coplanar with an antenna structure (AS) in the transponder chip module.

3. The coupling frame of claim 1 , wherein:
at least a portion of the coupling frame overlaps at least a portion of an antenna structure (AS) in the transponder chip module (TCM).

4. The coupling frame (CF) of claim 1 , wherein:
the transponder chip module (TCM) comprises an etched antenna structure (AS, LES); and
the module opening (MO) is spaced from 50 μm to 300 μm from the antenna structure.

5. The coupling frame (CF) of claim 1 , wherein:
the metal layer (ML) has a thickness greater than a transparency threshold for a material of the metal layer (ML).

6. A method of enhancing coupling of a transponder chip module (TCM) with an external reader, wherein the transponder chip module is disposed in a card body (CB, MCB) of a smart card having a metal layer (ML) and comprises an antenna structure (AS), characterized by:
forming the metal layer as a coupling frame (CF) closely adjacent to and surrounding the transponder chip module, wherein the coupling frame has an opening for receiving the transponder chip module and a slit (S) or a non-conductive stripe (NCS), extending from the opening to a periphery of the metal layer.

7. The method of claim 6 , wherein:
the coupling frame is substantially coplanar with the antenna structure (AS).

8. A smartcard comprising:
a transponder chip module comprising an RFID chip and an antenna; and
a coupling frame, comprising:
a metal layer;
an opening in the metal layer for receiving the transponder chip module; and
a discontinuity, comprising a slit or a non-conductive stripe, extending from the opening to a periphery of the metal layer;

wherein the coupling frame is disposed coplanar with the transponder chip module.

9. The smartcard of claim 8 , wherein, when the transponder chip module is disposed in the opening, the smartcard is characterized by at least one of:
the coupling frame is disposed closely adjacent to the transponder chip module; and
a portion of the coupling frame overlaps a portion of an antenna structure (AS) in the transponder chip module.

10. The smartcard of claim 8 , wherein the smartcard is characterized by at least one of:
the coupling frame extends over substantially the entire area of the smartcard;
the metal layer comprises a metal card body (MCB) of a metal smartcard.

11. The smartcard of claim 8 , wherein the slit is characterized by at least one of:
the slit extends completely through the metal layer;
the slit extends only partially through the metal layer, and remaining material of the metal layer below the slit has a thickness below a transparency threshold for the metal layer;
the slit has a width which is smaller than the opening;
the slit is at least partially filled with an electrically non-conducting material selected from the group consisting of polymer and epoxy resin, reinforced epoxy resin; and
a reinforcing structure (RS) disposed at a location of the slit (S) to reinforce the metal layer (ML).

12. The smartcard of claim 8 , wherein the metal layer comprises a material having a thickness selected from the group consisting of:
a thickness greater than a transparency threshold for absorbing electromagnetic waves at a frequency of interest;
a thickness greater than a skin depth for conducting electricity at a frequency of interest;
a thickness greater than 1 μm;
a thickness greater than 30 μm; and
a thickness up to the total normal thickness of a smartcard.

13. The smartcard of claim 8 , wherein the metal layer is characterized by at least one of:
the metal layer comprises a material selected from the group consisting of copper, aluminum, brass, titanium, tungsten, stainless steel, silver, graphene, silver nanowires and conductive carbon ink;
the metal layer is disposed on a non-conductive layer by a process selected from the group consisting of silk screen printing and vapor deposition;
the metal layer comprises a mesh; and
the metal layer comprises an engraving, embossing, or stamped feature/logo/ID which serves as a security feature for the smartcard.

14. The smartcard of claim 8 , wherein a gap between an inner edge of the coupling frame and an outer feature of an antenna structure (AS) in the transponder chip module is characterized by at least one of:
the gap is less than 300 μm; and
the gap is approximately 50 μm.

15. The smartcard of claim 8 , wherein:
the metal layer (ML) is substantially coplanar with an antenna structure (AS) in the transponder chip module.

16. The smartcard of claim 8 , wherein:
an antenna structure (AS) in the transponder chip module comprises a substantially planar, etched structure having a number of tracks separated by spaces.

17. The smartcard of claim 16 , wherein the spaces between tracks are at least one of:
less than 100 μm;
less than 75 μm;
less than 50 μm;
less than 25 μm; and
less than the width of a laser beam.

18. The smartcard of claim 8 , wherein
an activation distance for a transponder chip module disposed in the opening of the coupling frame is at least one of:
at least 20 mm;
at least 25 mm;
at least 30 mm;
at least 35 mm; and
at least 40 mm.

19. The smartcard of claim 8 , further comprising at least one of:
a switch (SW) connected across ends of the coupling frame (CF); and
an LED connected across ends of the coupling frame (CF).

Assignees

• Finn David
• Lotya Mustafa
• Molloy Darren
• Féinics Amatech Teoranta

Inventors

• Finn David
• Lotya Mustafa
• Molloy Darren

Classifications

• H01Q1/2225

  used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal · CPC title

• G06K19/07794

  the record carrier comprising a booster or auxiliary antenna in addition to the antenna connected directly to the integrated circuit · CPC title

• G06K19/07722

  the record carrier being multilayered, e.g. laminated sheets (flat articles in general, see B32B37/00) · CPC title

• B23K26/40

  taking account of the properties of the material involved · CPC title

• B23K2103/50

  Inorganic materials other than metals or composite materials · CPC title