Electronic device having force touch function

• US 10,175,804 B2
• Filed: 12/29/2015
• Issued: 01/08/2019
• Est. Priority Date: 09/30/2015
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Yoon, SeungHwan, Kim, KiDuk, Hwang, JongHee, Lim, DongKyun, Kim, EunJung
• Primary Examiner(s): Mishler, Robin
• Application Number:
  US14/982,841
• Publication Number:
  US 20170090637A1
• Time in Patent Office: 1,106 Days
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04144 using an array of force sensing means position sensing using the local deformation of sensor cells G06F3/0447
• 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 3/0446 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: H04M 1/0266 for a display module assembly
• CPC Class Codes: H04M 2201/38 Displays
• CPC Class Codes: H04M 2250/22 including a touch pad, a touch sensor or a touch detector digitizers for touch screens G06F3/041

Abstract

An electronic device has a force touch function. The electronic device includes an image display module having a touch electrode. A cover window attaches to a front surface of the image display module. A housing receives the image display module therein, and supports the cover window. A panel moving part is between the housing and the image display module. A driving circuit senses a touch force based on a distance between the image display module and the housing which are spaced from each other with the panel moving part interposed in-between.

Claims

1. An electronic device having a force touch function comprising:

an image display module having a touch electrode;

a cover window attached to a front surface of the image display module;

an electrically grounded housing for receiving the image display module therein, and supporting the cover window, the housing including a housing plate that covers a rear surface of the image display module;

a panel moving part disposed between the housing plate and the image display module; and

a driving circuit for operating in a first touch mode to sense a touch force based on a sensed mutual capacitance varying with distance between the touch electrode and the housing plate which are spaced from each other with the panel moving part interposed in-between, and the driving circuit operating in a second touch mode to sense a touch position based on a sensed self-capacitance of the touch electrode; and

a host controller to control the image display module to drive display of an image during a display mode set in a first period of a first frame and a first period of a second frame, control the driving circuit to operate in the first touch mode during a second period of the first frame, and control the driving circuit to operate in the second touch mode during a second period of the second frame.

2. The electronic device according to claim 1, wherein the housing further includes a housing sidewall coupled to the housing plate, the housing sidewall covering a lateral surface of the image display module and supporting the cover window.

3. The electronic device according to claim 2, wherein the housing further includes an impact-absorbing member, which is disposed between the cover window and the housing sidewall, the impact-absorbing member for movably supporting the cover window.

4. The electronic device according to claim 1,

wherein the image display module includes a display panel,

wherein the display panel includes:

a lower substrate including gate and data lines crossing each other, and a common electrode prepared in a pixel region defined by the gate and data lines; and

an upper substrate bonded to the lower substrate with a liquid crystal layer interposed therebetween,

wherein the common electrode comprises the touch electrode.

5. The electronic device according to claim 1, wherein the display panel includes a transparent conductive layer prepared on a rear surface of the lower substrate facing the housing plate, and the transparent conductive layer is electrically floating.

6. The electronic device according to claim 1, wherein the display panel includes:

a lower substrate including gate and data lines crossing each other, and a common electrode prepared in a pixel region defined by the gate and data lines; and

an upper substrate bonded to the lower substrate with a liquid crystal layer interposed therebetween,

wherein a transparent conductive layer covers a rear surface of the lower substrate facing the housing plate and is connected with the driving circuit,

the common electrode comprises the touch electrode for sensing the touch position, and

the transparent conductive layer comprises a first touch force electrode for sensing the force touch.

7. The electronic device according to claim 6, wherein the transparent conductive layer includes a plurality of conductive patterns spaced at fixed intervals.

8. The electronic device according to claim 6,

wherein the housing further includes a force electrode member prepared in the housing plate and connected with the driving circuit,

wherein the force electrode member comprises a second touch force electrode for sensing the force touch.

9. The electronic device according to claim 8, wherein the driving circuit generates the force raw data by sensing the change of capacitance between the transparent conductive layer and the force electrode member in accordance with the change of distance between the transparent conductive layer and the force electrode member spaced from each other with the panel moving part interposed in-between, and

wherein the force electrode member includes a single force electrode pattern or a plurality of force electrode patterns spaced at fixed intervals.

10. The electronic device according to claim 1, wherein the driving circuit generates touch driving signals having a same phase and a same potential difference and provides the generated touch driving signals to the gate line, the data line and the touch electrode, wherein the touch electrode provide touch position sensing data in response to the touch driving signal.

11. The electronic device according to claim 1, wherein the display panel includes:

a base substrate;

a back plate attached to a rear surface of the base substrate facing the housing plate;

a pixel array on the base substrate, the pixel array including a pixel having an organic light emitting device;

an encapsulation layer covering the pixel array; and

a touch panel attached to the encapsulation layer, the touch panel having the touch electrode.

12. The electronic device according to claim 1, wherein the display panel includes a conductive layer prepared on a rear surface of the back plate facing the housing plate, and the conductive layer is electrically floating.

13. An electronic device having a force touch function comprising:

an image display module;

a cover window attached to a front surface of the image display module;

a housing for receiving the image display module therein, and supporting the cover window, the housing including a housing plate that covers a rear surface of the image display module;

a base substrate;

a back plate attached to a rear surface of the base substrate facing the housing plate;

a pixel array on the base substrate, the pixel array including a pixel having an organic light emitting device;

an encapsulation layer for covering the pixel array;

a touch panel attached to the encapsulation layer, the touch panel having a touch electrode; and

a conductive layer on a rear surface of the back plate facing the housing plate, wherein the conductive layer comprises a touch force electrode, and includes a single conductive pattern or a plurality of conductive patterns spaced at fixed intervals;

a panel moving part disposed between the housing plate and the image display module; and

a driving circuit for operating in a first touch mode to sense a touch force based on a sensed mutual capacitance varying with distance between the touch force electrode and the housing plate which are spaced from each other with the panel moving part interposed in-between, and the driving circuit to operate in a second touch mode to sense a touch position based on a sensed self-capacitance of the touch electrode; and

a host controller to control the pixel array to drive display of an image during a display mode set in a first period of a first frame and a first period of a second frame, control the driving circuit to operate in the first touch mode during a second period of the first frame, and control the driving circuit to operate in the second touch mode during a second period of the second frame.

14. The electronic device according to claim 13, wherein the housing further includes a force electrode member in the housing plate and connected with the driving circuit, wherein the force electrode member comprises a second touch force electrode for sensing a force touch.

15. The electronic device according to claim 14, wherein the driving circuit senses the touch force by sensing the change of capacitance between the touch force electrode of the conductive layer and the force electrode member in accordance with the change of distance between the touch force electrode of the conductive layer and the force electrode member spaced from each other with the panel moving part interposed in-between,

wherein the force electrode member includes a single force electrode pattern or a plurality of force electrode patterns spaced at fixed intervals.

16. An electronic device for sensing a touch, the electronic device comprising:

an image display module comprising a display panel to display an image in response to an image signal, the image display module including a touch electrode and a transparent conductive layer below the touch electrode;

a cover window attached to the front surface of the image display module;

a housing comprising a housing plate covering a rear surface of the image display module and sidewalls covering lateral surfaces of the image display module and supporting the cover window, the housing supporting the image display module such that a gap exists between the housing plate and the rear surface of the image display module;

a touch driver circuit to sense a position of the touch based on a self-capacitance signal from the touch electrode;

a touch force circuit to sense a touch force of the touch based on a change in a mutual capacitance between the housing plate and the transparent conductive layer, the change in the mutual capacitance caused by a change in distance between the transparent conductive layer and the housing plate in response to the touch force and the touch force circuit to generate force data estimating the touch force applied to the image display module; and

a host controller to control the image display module to drive display of an image during a display mode set in a first period of a first frame and a first period of a second frame, control the touch driver circuit to sense the position of the touch during a second period of the first frame, and to control the touch force circuit to sense the touch force of the touch during a second period of the second frame.

17. The electronic device according to claim 16, wherein the transparent conductive layer is electrically floating, and wherein the housing plate is electrically grounded.

18. The electronic device according to claim 17, wherein the transparent conductive layer includes a plurality of conductive patterns spaced at first intervals.

19. The electronic device according to claim 18, wherein each of the plurality of conductive patterns comprises a bar shape having a length parallel to a first direction and are spaced at the first intervals along a second direction perpendicular to the first direction.

20. The electronic device according to claim 18, wherein each of the plurality of conductive patterns comprises has a length parallel to a first direction and are spaced at the first intervals along a second direction perpendicular to the first direction, wherein each of the plurality of conductive patterns comprises a plurality of pattern electrodes in a polygonal shape spaced at second intervals along the first direction, and bridge electrodes between each pair of neighboring pattern electrodes to connect the neighboring pattern electrodes.

21. The electronic device according to claim 17, wherein the housing plate comprises a force electrode member, wherein the touch driver circuit senses the mutual capacitance between the transparent conductive layer and the force electrode member.

22. The electronic device according to claim 21, wherein the transparent conductive layer comprises a plurality of conductive patterns spaced at first intervals and wherein the force electrode member comprises a uniform layer.

23. The electronic device according to claim 21,

wherein the transparent conductive layer comprises a first plurality of conductive patterns spaced at first intervals wherein each of the first plurality of conductive patterns has a length parallel to a first direction and are spaced at first intervals along a second direction perpendicular to the first direction, and

wherein the force electrode member includes a plurality of force electrode patterns spaced at first intervals wherein each of the plurality of force electrode patterns has a length parallel to the second direction and are spaced at second intervals along the first direction.