Touch panel and image display device including the same

• US 9,110,546 B2
• Filed: 12/18/2012
• Issued: 08/18/2015
• Est. Priority Date: 06/21/2012
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Kim, Sung-Chul, Lee, Jung-Han
• Primary Examiner(s): Johnson, Allison
• Assistant Examiner(s): CHOWDHURY, AFROZA Y
• Application Number:
  US13/718,260
• Publication Number:
  US 20130342498A1
• Time in Patent Office: 973 Days
• Field of Search: 345/173, 345/174
• US Class Current: 1/1
• 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 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G09G 2354/00 Aspects of interface with display user
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 2217/960715 Rc-timing; e.g. measurement of variation of charge time or discharge time of the sensor

Abstract

A self capacitance type touch panel includes a touch driver including a plurality of touch ICs; and a touch unit including a plurality of touch groups that are controlled by the plurality of touch ICs, respectively, wherein each of the plurality of touch groups includes a plurality of pattern electrodes, and some touch ICs selected from the plurality of touch ICs apply sensing voltages to respective corresponding touch groups at a same timing.

Claims

1. A self capacitance type touch panel, comprising:

a touch driver including a plurality of touch ICs; and

a touch unit including a plurality of touch groups that are controlled by the plurality of touch ICs, respectively,

wherein each of the plurality of touch groups includes a plurality of pattern electrodes, and some touch ICs selected from the plurality of touch ICs apply sensing voltages to respective corresponding touch groups at a same timing, and

wherein the plurality of touch ICs that apply the sensing voltage to the respective touch groups at the same timing control the respective touch groups using sensing voltages adjusted to have the same phase and stored in advance.

2. The touch panel according to claim 1, wherein each touch IC comprises:

a memory unit configured to store a reference sensing time period for each pattern electrode, taken for the sensing voltage to be charged or discharged to be a sensed voltage before a touch input is generated; and

a comparator configured to compare a changed sensing time period received from the memory unit when the touch input has been generated, to the reference sensing time period, and to determine whether or not a touch has occurred according to the results of the comparison.

3. The touch panel according to claim 1, wherein the touch driver further comprises a voltage switching unit configured to transfer the sensing voltage or a common voltage to the pattern electrodes.

4. The touch panel according to claim 1, wherein the touch driver further comprises a touch group switching unit configured to switch connections of output channels of each touch IC in order to change touch groups that are controlled by the touch IC.

5. An image display device, comprising:

a display panel for displaying an image; and

a self capacitance type touch panel sensing a touch input, including;

a touch driver including a plurality of touch ICs; and

a touch unit including a plurality of touch groups that are controlled by the plurality of touch ICs, respectively,

wherein each of the plurality of touch groups includes a plurality of pattern electrodes, and some touch ICs selected from among the plurality of touch ICs apply sensing voltages to respective corresponding touch groups at a same timing, and

wherein the plurality of touch ICs that apply the sensing voltage to the respective touch groups at the same timing control the respective touch groups using sensing voltages adjusted to have the same phase and stored in advance.

6. The image display device according to claim 5, wherein each touch IC comprises:

a memory unit configured to store a reference sensing time period for each pattern electrode, taken for the sensing voltage to be charged or discharged to be a sensed voltage before a touch input is generated; and

a comparator configured to compare a changed sensing time period received from the memory unit when the touch input has been generated, to the reference sensing time period, and to determine whether or not a touch has occurred according to the results of the comparison.

7. The image display device according to claim 5, wherein the touch driver further comprises a voltage switching unit configured to transfer the sensing voltage or a common voltage to the pattern electrodes.

8. The image display device according to claim 5, wherein the touch driver further comprises a touch group switching unit configured to switch connections of output channels of each touch IC in order to change touch groups that are controlled by the touch IC.