Borderless touch panel design

• US 9,128,560 B2
• Filed: 01/10/2013
• Issued: 09/08/2015
• Est. Priority Date: 01/10/2013
• Status: Active Grant

• Current Assignee: STMicroelectronics International N.V. (STMicroelectronics NV)
• Original Assignee: STMicroelectronics Asia Pacific Pte Limited (STMicroelectronics NV)
• Inventors: Ng, Chee Yu, Chandran, Praveesh
• Primary Examiner(s): PATEL, PREMAL R
• Application Number:
  US13/738,081
• Publication Number:
  US 20140191978A1
• Time in Patent Office: 971 Days
• Field of Search: 345173-179
• US Class Current: 1/1
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• 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: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality

Abstract

A borderless touchscreen panel includes a first conductive layer having rows of capacitive sensors and receiving traces, and a second conductive layer having columns of sensor bars and transmitting traces. The capacitive sensors are coupled to control circuitry via the receiving traces, and the sensor bars are coupled to the control circuitry via the transmitting traces. Peripheral sensor bars are disposed over the receiving traces such that the receiving traces can be routed within an active portion of the borderless touchscreen panel without obstructing its touch-detection capabilities. Furthermore, the receiving traces are comprised of a transparent material such as indium tin oxide, and therefore do not obstruct the display capabilities of the active portion. Thus, there is no need for an inactive border region since the receiving traces are disposed within the active portion without obstructing either the touch-detection or display capabilities of the borderless touchscreen panel.

Claims

1. A borderless touchscreen panel, comprising:

a plurality of transmit electrodes each extending in a first direction, the plurality of transmit electrodes including a first transmit electrode and a last transmit electrode;

a plurality of sensing electrodes extending in a second direction perpendicular to the first direction, wherein a first subset of the plurality of sensing electrodes are coupled to receiving traces routed beneath the first transmit electrode and extending in the first direction along a length of the first transmit electrode, and a second subset of the plurality of sensing electrodes are coupled to receiving traces routed beneath the last transmit electrode and extending in the first direction along a length of the last transmit electrode; and

control circuitry operable during a first mode to apply first drive signals to the plurality of transmit electrodes except the first transmit electrode and to receive first sense signals from the first subset via the receiving traces routed beneath the first transmit electrode.

2. The borderless touchscreen panel of claim 1, wherein the first sense signals are indicative of sensed capacitance at locations where the first subset of the plurality of sensing electrodes intersect the transmit electrodes.

3. The borderless touchscreen panel of claim 1, wherein the control circuitry is further operable during a second mode to apply second drive signals to the plurality of transmit electrodes except the last transmit electrode and to receive second sense signals from the second subset via the receiving traces routed beneath the last transmit electrode.

4. The borderless touchscreen panel of claim 3, wherein the second sense signals are indicative of sensed capacitance at locations where the second subset of the plurality of sensing electrodes intersect the transmit electrodes.

5. A borderless touchscreen panel, comprising:

a first layer comprising rows of series-connected sensing electrodes;

a second layer comprising a plurality of transmit electrodes, including a first transmit electrode and a last transmit electrode, each of the plurality of transmit electrodes extending in a first direction perpendicular to the rows of series-connected sensing electrodes,

wherein the first layer further comprises;

a first set of receiving traces routed beneath the first transmit electrode and extending in the first direction along a length of the first transmit electrode, the first set of receiving traces coupled to a first subset of the rows of series-connected sensing electrodes, and

a second set of receiving traces routed beneath the last transmit electrode and extending in the first direction along a length of the last transmit electrode, the second set of receiving traces coupled to a second subset of the rows of series-connected sensing electrodes; and

control circuitry operable during a first mode to apply first drive signals to the plurality of transmit electrodes except the first transmit electrode and to receive first sense signals from the first subset of the rows of series-connected sensing electrodes via the first set of receiving traces routed beneath the first transmit electrode.

6. The borderless touchscreen panel of claim 5, wherein the first sense signals are indicative of sensed capacitance at locations where the first subset of the rows of series-connected sensing electrodes intersect the transmit electrodes.

7. The borderless touchscreen panel of claim 5, wherein the second layer further comprises transmitting traces coupled to the plurality of transmit electrodes, the transmitting traces operable to transmit drive signals from the control circuitry to respective transmit electrodes.

8. The borderless touchscreen panel of claim 5, wherein the control circuitry is further operable during a second mode to apply second drive signals to the plurality of transmit electrodes except the last transmit electrode and to receive second sense signals from the second subset of the rows of series-connected sensing electrodes via the second set of receiving traces routed beneath the last transmit electrode.

9. The borderless touchscreen panel of claim 8, wherein the second sense signals are indicative of sensed capacitance at locations where the second subset of the rows of series-connected sensing electrodes intersect the transmit electrodes.

10. A borderless touchscreen panel, comprising:

a plurality of rows of series-connected sensing electrodes;

a plurality of transmit electrodes each extending in a first direction perpendicular to the rows of series-connected sensing electrodes, the plurality of transmit electrodes including;

a last transmit electrode, the last transmit electrode operable during a first mode to receive a first drive signal, and

a first transmit electrode, the first transmit electrode operable during a second mode to receive a second drive signal;

a first set of receiving traces routed beneath the first transmit electrode and extending in the first direction along a length of the first transmit electrode, the first set of receiving traces coupled to a first subset of the plurality of rows of series-connected sensing electrodes and operable during the first mode to provide first sense signals from the first subset of the plurality of series-connected sensing electrodes;

a second set of receiving traces routed beneath the last transmit electrode and extending in the first direction along a length of the last transmit electrode, the second set of receiving traces coupled to a second subset of the plurality of rows of series-connected sensing electrodes and operable during the second mode to provide second sense signals from the second subset of the plurality of series-connected sensing electrodes; and

control circuitry operable during the first mode to apply the first drive signal to the plurality of transmit electrodes except the first transmit electrode and to receive the first sense signals from the first set of receiving traces.

11. The borderless touchscreen panel of claim 10, wherein the first sense signals are indicative of sensed capacitance at locations where the first subset of the plurality of rows of series-connected sensing electrodes intersect the transmit electrodes.

12. The borderless touchscreen panel of claim 10, further comprising transmitting traces coupled to the plurality of transmit electrodes, the transmitting traces operable to transmit drive signals from the control circuitry to respective transmit electrodes.

13. The borderless touchscreen panel of claim 10, wherein the control circuitry is further operable during the second mode to apply the second drive signal to the plurality of transmit electrodes except the last transmit electrode and to receive the second sense signals from the second set of receiving traces.

14. The borderless touchscreen panel of claim 13, wherein the second sense signals are indicative of sensed capacitance at locations where the second subset of the plurality of rows of series-connected sensing electrodes intersect the transmit electrodes.