Providing near field communication through a touch screen

• US 9,513,756 B1
• Filed: 08/28/2015
• Issued: 12/06/2016
• Est. Priority Date: 08/28/2015
• Status: Active Grant

• Current Assignee: Clover Network, Inc. (Fiserv Incorporated)
• Original Assignee: Clover Network, Inc. (Fiserv Incorporated)
• Inventors: Mishra, Abhinayak, Pan, Victor
• Primary Examiner(s): Awad, Amr
• Assistant Examiner(s): Flores, Roberto
• Application Number:
  US14/839,600
• Time in Patent Office: 466 Days
• Field of Search: 345/173, 345/174, 345/178, 455/41.1, 343/720
• US Class Current: 1/1
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06Q 20/20 Point-of-sale [POS] network systems
• CPC Class Codes: G06Q 20/3278 RFID or NFC payments by means of M-devices
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/72 for local intradevice communication

Abstract

Embodiments of the present invention enable near field communication (NFC) through a touch display. Some embodiments include specialized touch displays with lower electromagnetic dissipation factors than standard touch displays. Some embodiments include methods and devices for detecting the activation or deactivation of NFC communication using the touch display and adapting the touch display to that activation or deactivation. Disclosed techniques for adapting the touch display include optimizing the behavior of the touch display for operation in the face of electromagnetic interference when NFC is activated and conducting a partial recalibration of the touch display when NFC is deactivated.

Claims

1. A device comprising:

a body of the device

a transparent cover layer with an exposed surface;

a touch stack covered by the transparent cover layer, wherein the touch stack includes;

(i) an array of capacitive touch detection points; and

(ii) a transparent dielectric;

a plastic frame;

a display with a set of components and a diagonal dimension in excess of five inches, covered by the touch stack; and

a near field communication antenna covered by the display and located entirely within the lateral extent of the display; and

a printed circuit board within the body of the device and including a touch controller and a near field communication controller;

wherein the antenna is located between the printed circuit board and the display;

wherein at least a portion of the plastic frame is covered by the display;

wherein the plastic frame supports the display;

wherein the plastic frame holds and aligns the set of components of the display;

wherein there are no solid planes of conductive material that;

(i) span the diagonal dimension; and

(ii) are located between the near field communication antenna and the transparent cover layer; and

wherein there is no ground plane in the touch stack.

2. The device of claim 1, wherein:

the near field communication antenna is a near field communication antenna and includes a coiled inductor;

the display is a liquid crystal display; and

each capacitive touch detection point in the array of capacitive touch detection points is defined by a cross over point between a transmission line and a receiving line separated from the transmission line by a dielectric layer.

3. The device of claim 1, further comprising:

a touch controller that is communicatively coupled to the array of capacitive touch detection points; and

a comparator instantiated in the touch controller to compare a current baseline of the array of capacitive touch detection points to a trigger level;

wherein the trigger level is stored in the touch controller and is higher than a noise floor baseline of the array of capacitive touch detection points when the near field communication antenna is not activated.

4. The device of claim 1, further comprising:

an antenna controller that is communicatively coupled to the near field communication antenna; and

a touch controller that is communicatively coupled to the antenna controller via a digital communication interface and communicatively coupled to the array of capacitive touch detection points;

wherein the touch controller receives an indication that the near field communication antenna is active via the digital communication interface.

5. The device of claim 1, further comprising:

a touch controller that is communicatively coupled to the array of capacitive touch detection points;

a memory that stores;

(i) a current set of calibration values for access by a processor of the touch controller; and

(ii) a set of prior calibration values;

wherein the set of prior calibration values are stored to the memory before the near field communication antenna is deactivated; and

wherein the set of prior calibration values are read from the memory by the processor after the near field communication antenna is deactivated.

6. The device of claim 5, wherein the set of prior calibration values includes at least two of:

a noise floor baseline level, a baseline increase threshold, a noise filter enable flag, a touch array report rate, and a touch array touch point count.

7. A system comprising:

a device having;

a body;

a plastic frame;

an internal near field communication antenna;

a capacitive touch display having a set of components, a diagonal dimension of at least 5 inches and entirely covering the internal near field communication antenna;

a transparent cover layer covering the capacitive touch display and having an exposed surface;

a printed circuit board within the body of the device and including a touch controller and a near field communication controller;

wherein the antenna is located between the printed circuit board and the display;

wherein at least a portion of the plastic frame is covered by the display;

wherein the plastic frame supports the display;

wherein the plastic frame holds and aligns the set of components of the display; and

wherein there are no solid planes of conductive material that;

(i) span the diagonal dimension; and

(ii) are located between the near field communication antenna and the transparent cover layer; and

an external near field communication antenna in operative communication with the internal near field communication antenna through the capacitive touch display.

8. The system of claim 7, further comprising:

a touch stack in the capacitive touch display;

wherein there are no solid planes of conductive material that;

(i) span the diagonal dimension; and

(ii) are located between the internal near field communication antenna and the transparent cover layer; and

wherein there is no ground plane in the touch stack.

9. The system of claim 7, further comprising:

a plastic frame;

wherein at least a portion of the plastic frame is covered by the capacitive touch display; and

wherein the plastic frame supports the capacitive touch display.

10. The system of claim 7, further comprising:

a communication path between the external near field communication antenna and the internal near field communication antenna that is intersected by the capacitive touch display;

wherein the capacitive touch display is the most prominent contributor to an electromagnetic dissipation factor of the communication path.

11. The system of claim 7, further comprising:

a communication path between the external near field communication antenna and the internal near field communication antenna that is intersected by the capacitive touch display;

wherein the electromagnetic dissipation factor of the communication path is low enough to allow the near field communication antenna to induce a direct current voltage of greater than 2.55 Volts in a contactless analog test card at a distance of 4 Centimeters from the exposed surface with an input of 2 Watts to the near field communication antenna.

12. The system of claim 7, further comprising:

an array of capacitive touch detection points located in the capacitive touch display; and

a touch controller in operative communication with the array of capacitive touch detection points;

wherein the touch controller stores instructions to execute a method comprising;

measuring a stream of touch values received from the array of capacitive touch detection points;

determining a current baseline of the stream of touch values;

comparing the current baseline of the stream of touch values to a trigger level to produce a comparison; and

switching the touch controller from an antenna-deactivated mode to an antenna-activated mode based upon the comparison.

13. The system of claim 7, further comprising:

an array of capacitive touch detection points located in the capacitive touch display; and

a touch controller in operative communication with the array of capacitive touch detection points;

wherein the touch controller stores instructions to execute a method comprising;

detecting deactivation of the internal near field communication antenna using a measurement from the capacitive touch detection points; and

reading a stored set of calibration values from a memory of the touch controller after detecting deactivation of the internal near field communication antenna.