Apparatus for driving of a touch panel having a dummy electrode and haptic mode

• US 9,851,840 B2
• Filed: 05/05/2016
• Issued: 12/26/2017
• Est. Priority Date: 08/26/2014
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Hwang, Jong Hee, Cho, Sung Yong, Kim, Eun Jung, Kim, Ki Seon
• Primary Examiner(s): Pham, Long D
• Application Number:
  US15/147,506
• Publication Number:
  US 20160283031A1
• Time in Patent Office: 600 Days
• Field of Search: 345173
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• 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 3/0447 Position sensing using the local deformation of sensor cells
• CPC Class Codes: G06F 3/047 using sets of wires, e.g. crossed wires

Abstract

Embodiments relate to a touch panel with a haptic function and a method of operating the touch panel. The touch panel includes first electrodes and second electrodes intersecting the first electrodes. The touch panel further includes an elastic dielectric member disposed between the first electrodes and the second electrodes to separate the first electrodes and the second electrodes. The first electrodes are applied with a touch driving pulse during a sensing mode, and are applied with a voltage during a haptic mode. The second electrodes sense a touch sense signal responsive to the touch driving pulse in the sensing mode, and the second electrodes are applied with a reference voltage in the haptic mode. The elastic dielectric member vibrates in response to the voltage applied to the first electrodes in the haptic mode.

Claims

1. An apparatus comprising:

a touch panel including a plurality of touch driving electrodes, an elastic dielectric member provided on the plurality of touch driving electrodes, and a plurality of touch sensing electrode groups provided on the elastic dielectric member and respectively intersected and overlapped with the plurality of touch driving electrodes, wherein each of the touch sensing electrode groups includes a touch sensing electrode and a first dummy electrode being in parallel to each other on the elastic dielectric member; and

a touch driving circuit configured to;

in a touch point sensing mode, electrically float the first dummy electrode in a unit of a touch sensing electrode group and sense a change of capacitance through the touch sensing electrode of the touch sensing electrode group, and

in a haptic mode, apply a voltage to a touch driving electrode and apply a reference voltage to the touch sensing electrode group, wherein the first dummy electrode of the touch sensing electrode group is electrically connected with the touch sensing electrode in the unit of the touch sensing electrode group in the haptic mode, and

wherein the touch driving circuit generates touch force sensing data by electrically connecting the first dummy electrode to the touch sensing electrode in the unit of the touch sensing electrode group and sensing another change of capacitance through the touch sensing electrode while supplying a touch driving pulse to the touch driving electrode in accordance with a touch force sensing mode.

2. The apparatus according to claim 1, wherein the voltage applied to the touch driving electrode is an AC voltage at a predetermined frequency.

3. The apparatus according to claim 2, wherein the elastic dielectric member varies according to an amplitude of the AC voltage.

4. The apparatus according to claim 1, wherein the elastic dielectric member is comprised of PDMS (polydimethylsiloxane), acrylic or poly-urethane material.

5. The apparatus according to claim 1,

wherein the touch driving circuit generates touch point sensing data by electrically floating the first dummy electrode in a unit of the touch sensing electrode group and sensing the change of capacitance through the touch sensing electrode while supplying the touch driving pulse to the touch driving electrode in accordance with the touch point sensing mode.

6. The apparatus according to claim 5, wherein each of the touch sensing electrode groups includes a second dummy electrode being in parallel to the first dummy electrode with the touch sensing electrode interposed therebetween,

wherein the touch driving circuit electrically floats the first dummy electrode and the second dummy electrode in the unit of the touch sensing electrode group in accordance with the touch point sensing mode, and electrically connects the first dummy electrode and the second dummy electrode with the touch sensing electrode in the unit of the touch sensing electrode group in accordance with the touch force sensing mode.

7. The apparatus according to claim 6, further comprising a haptic control circuit for determining a haptic area and haptic intensity based on at least one of the touch point sensing data and the touch force sensing data, and generating a haptic mode signal corresponding to the determined haptic area and the haptic intensity in accordance with the haptic mode.

8. The apparatus according to claim 7, wherein the touch driving circuit applies the voltage to the touch driving electrode in the haptic area and applies the reference voltage to the first dummy electrode, the second dummy electrode, and the touch sensing electrode for the touch sensing electrode group included in the haptic area based on the haptic mode signal.

9. The apparatus according to claim 8, wherein the touch driving circuit includes:

a driving signal supplying part for supplying the touch driving pulse to the touch driving electrode in accordance with the touch point sensing mode and the touch force sensing mode, and generating the voltage corresponding to the haptic mode signal in accordance with the haptic mode and supplying the generated voltage corresponding to the haptic mode signal to the touch driving electrode;

an electrode connecting part for electrically floating the first dummy electrode and the second dummy electrode in the unit of the touch sensing electrode group in accordance with the touch point sensing mode, electrically connecting the first dummy electrode and the second dummy electrode to the touch sensing electrode in the unit of the touch sensing electrode group in accordance with the touch force sensing mode, and applying the reference voltage to the first dummy electrode, the second dummy electrode, and the touch sensing electrode for the touch sensing electrode group included in the haptic area in accordance with the haptic mode;

a sensing part for generating the touch point sensing data and the touch force sensing data, wherein the sensing part is connected with the touch sensing electrode through the electrode connecting part in accordance with the touch point sensing mode and the touch force sensing mode so as to sense the change of capacitance through the touch sensing electrode; and

a sensing data processing part for storing the touch point sensing data and the touch force sensing data provided from the sensing part in a memory, and transmitting the touch point sensing data and the touch force sensing data stored in the memory to a host system.

10. The apparatus according to claim 9, wherein the electrode connecting part includes:

a first switching device for electrically floating the first dummy electrode by each of the touch sensing electrode groups in accordance with the touch point sensing mode, and electrically connecting the first dummy electrode to the touch sensing electrode by each of the touch sensing electrode groups in accordance with the touch force sensing mode or the haptic mode;

a second switching device for electrically floating the second dummy electrode by each of the touch sensing electrode groups in accordance with the touch point sensing mode, and electrically connecting the second dummy electrode to the touch sensing electrode by each of the touch sensing electrode groups in accordance with the touch force sensing mode or the haptic mode; and

a multiplexer for connecting the touch sensing electrode to the sensing part by each of the touch sensing electrode groups in accordance with the touch point sensing mode or the touch force sensing mode, and supplying the reference voltage to the touch sensing electrode by each of the touch sensing electrode groups in accordance with the haptic mode.

11. The apparatus according to claim 6, wherein each of the touch sensing electrode groups includes a dummy bridge electrode for electrically connecting one side of the first dummy electrode with one side of the second dummy electrode.

12. The apparatus according to claim 11, further comprising a haptic control circuit for determining a haptic area and a haptic intensity based on at least one of the touch point sensing data and the touch force sensing data, and generating a haptic mode signal corresponding to the determined haptic area and the haptic intensity in accordance with the haptic mode.

13. The apparatus according to claim 12, wherein the touch driving circuit applies the voltage to the touch driving electrode in the haptic area and applies the reference voltage to the first dummy electrode, the second dummy electrode, and the touch sensing electrode for the touch sensing electrode group included in the haptic area based on the haptic mode signal.

14. The apparatus according to claim 13, wherein the touch driving circuit includes:

a driving signal supplying part for supplying the touch driving pulse to the touch driving electrode in accordance with the touch point sensing mode and the touch force sensing mode, and generating the voltage corresponding to the haptic mode signal in accordance with the haptic mode and supplying the generated voltage corresponding to the haptic mode signal to the touch driving electrode;

an electrode connecting part for electrically floating the first dummy electrode and the second dummy electrode in the unit of the touch sensing electrode group in accordance with the touch point sensing mode, electrically connecting the first dummy electrode and the second dummy electrode to the touch sensing electrode in the unit of the touch sensing electrode group in accordance with the touch force sensing mode, and applying the reference voltage to the first dummy electrode, the second dummy electrode, and the touch sensing electrode for the touch sensing electrode group included in the haptic area in accordance with the haptic mode;

a sensing part for generating the touch point sensing data and the touch force sensing data, wherein the sensing part is connected with the touch sensing electrode through the electrode connecting part in accordance with the touch point sensing mode and the touch force sensing mode so as to sense the change of capacitance through the touch sensing electrode; and

a sensing data processing part for storing the touch point sensing data and the touch force sensing data provided from the sensing part in a memory, and transmitting the touch point sensing data and the touch force sensing data stored in the memory to a host system.

15. The apparatus according to claim 14, wherein the electrode connecting part includes:

a first switching device for electrically floating the first dummy electrode by each of the touch sensing electrode groups in accordance with the touch point sensing mode, and electrically connecting the first dummy electrode to the touch sensing electrode by each of the touch sensing electrode groups in accordance with the touch force sensing mode or the haptic mode;

a second switching device for electrically floating the second dummy electrode by each of the touch sensing electrode groups in accordance with the touch point sensing mode, and electrically connecting the second dummy electrode to the touch sensing electrode by each of the touch sensing electrode groups in accordance with the touch force sensing mode or the haptic mode; and

a multiplexer for connecting the touch sensing electrode to the sensing part by each of the touch sensing electrode groups in accordance with the touch point sensing mode or the touch force sensing mode, and supplying the reference voltage to the touch sensing electrode by each of the touch sensing electrode groups in accordance with the haptic mode.

16. The apparatus according to claim 1, wherein the plurality of touch driving electrodes are disposed on a first surface of the elastic dielectric member and the plurality of touch sensing electrode groups are disposed on a second surface of the elastic dielectric member, the second surface facing away from the first surface, and wherein the elastic dielectric member is vibrated according to the voltage applied to the touch driving electrode and the reference voltage applied to the touch sensing electrode group in the haptic mode.