Display device and method of driving the same

• US 9,990,075 B2
• Filed: 11/10/2014
• Issued: 06/05/2018
• Est. Priority Date: 12/10/2013
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Kang, Seong Kyu, Kim, Hoon Bae, Han, Sung Su
• Primary Examiner(s): Edwards, Carolyn R
• Application Number:
  US14/537,534
• Publication Number:
  US 20150161964A1
• Time in Patent Office: 1,303 Days
• 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 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

Disclosed are a display device and method of driving the same in which a display panel may include a plurality of gate lines, a plurality of data lines and a touch panel, the touch panel including a first touch electrode group where s number of horizontal electrodes and k (which is less than s) number of longitudinal electrodes cross each other; and a touch sensing unit that during a first period of a plurality of touch sensing periods included in a one frame period, determines whether at least one of the s number of horizontal electrodes is touched based on a plurality of sensing signals received from at least two of the s number of horizontal electrodes, and during a second period of the plurality of touch sensing periods, determines whether at least one of the s number of horizontal electrodes, which is either the same or different from the at least one of the s number of horizontal electrodes determined during the first period, is touched based on one or more sensing signals received from at least one of the k number of longitudinal electrodes.

Claims

1. A display device comprising:

a display panel including a plurality of gate lines, a plurality of data lines and a touch panel, the touch panel including a first touch electrode group where s number of horizontal electrodes and k (which is less than s) number of longitudinal electrodes cross each other; and

a touch sensing unit that during a first period of a plurality of touch sensing periods included in a one frame period, determines whether at least one of the s number of horizontal electrodes is touched based on a plurality of sensing signals received from at least two of the s number of horizontal electrodes, and during a second period of the plurality of touch sensing periods in the one frame period, determines whether at least one of the s number of horizontal electrodes, which is either the same or different from the at least one of the s number of horizontal electrodes determined during the first period, is touched based on one or more sensing signals received from at least two of the k number of longitudinal electrodes,

wherein a driving voltage is alternatively supplied to the horizontal electrodes and the longitudinal electrodes in the one frame period, wherein the driving voltage is supplied to the longitudinal electrodes during the first period and the driving voltage is supplied to the horizontal electrodes during the second period, and wherein the first and second periods, which are different from each other, are touch sensing periods in the one frame period.

2. The display device of claim 1, wherein,

during the first period, the touch sensing unit sequentially supplies the driving voltage to the longitudinal electrodes, and determines whether the touch panel is touched, by using a plurality of sensing signals received from adjacent horizontal electrodes, and

during the second period, the touch sensing unit sequentially supplies the driving voltage to the horizontal electrodes, and determines whether the touch panel is touched, by using a plurality of sensing signals received from adjacent longitudinal electrodes.

3. The display device of claim 1, wherein,

When the driving voltage is supplied to an nth longitudinal electrode, by using a plurality of sensing signals received from an p (which is less than s number) th horizontal electrode and an p+1st horizontal electrode, the touch sensing unit determines whether the pth horizontal electrode is touched, and

when the driving voltage is supplied to an mth horizontal electrode, by using a plurality of sensing signals received from a first longitudinal electrode and a kth longitudinal electrode, the touch sensing unit determines whether the mth horizontal electrode is touched.

4. The display device of claim 1, wherein,

during first to kth touch sensing periods included in the first period, the touch sensing unit sequentially supplies the driving voltage to first to kth longitudinal electrodes, and by using a plurality of sensing signals received from first to sth horizontal electrodes, the touch sensing unit determines whether the first to s−

1st horizontal electrodes are touched, and

during one of k+1st to sth touch sensing periods included in the second period, the touch sensing unit supplies the driving voltage to the sth horizontal electrode, and by using a plurality of sensing signals received from first to kth longitudinal electrodes, the touch sensing unit determines whether the sth horizontal electrode is touched.

5. The display device of claim 1, wherein the touch sensing unit comprises:

the first touch electrode group formed in one side direction of the plurality of gate lines; and

a second touch electrode group in which s number of horizontal electrodes formed in parallel with the plurality of gate lines and k number of other longitudinal electrodes are formed to intersect each other in the other side direction of the plurality of gate lines.

6. The display device of claim 5, wherein,

during the first period of the plurality of touch sensing periods included in the one frame period, by using a plurality of sensing signals received from the horizontal electrodes constituting the second touch electrode group, the touch sensing unit determines whether the horizontal electrodes are touched, and

during the second period, by using a plurality of sensing signals received from the longitudinal electrodes constituting the second touch electrode group, the touch sensing unit determines whether the horizontal electrodes are touched.

7. The display device of claim 5, wherein,

during first to kth touch sensing periods included in the first period, the touch sensing unit sequentially supplies the driving voltage to first to kth longitudinal electrodes constituting the second touch electrode group, and by using a plurality of sensing signals received from first to sth horizontal electrodes constituting the second touch electrode group, the touch sensing unit determines whether the first to s−

1st horizontal electrodes are touched, and

during one of k+1st to sth touch sensing periods included in the second period, the touch sensing unit supplies the driving voltage to an sth horizontal electrode constituting the second touch electrode group, and by using a plurality of sensing signals received from the first to kth longitudinal electrodes constituting the second touch electrode group, the touch sensing unit determines whether the sth horizontal electrode constituting the second touch electrode group is touched.

8. The display device of claim 1, wherein the touch sensing unit comprises:

a driver configured to sequentially output a driving voltage;

a receiver configured to receive a sensing signal to determine whether there is a touch; and

a switching unit configured to, during first to kth touch sensing periods included in the first period, connect the driver to first to kth longitudinal electrodes and connect the receiver to first to sth horizontal electrodes, and during k+1st to sth touch sensing periods included in the second period, connect the driver to the first to sth horizontal electrodes and connects the receiver to the first to kth longitudinal electrodes.

9. The display device of claim 1, wherein the touch panel is an in-cell type touch panel.

10. The display device of claim 9, wherein the s number of horizontal electrodes are provided substantially in parallel with the plurality of gate lines in the display panel.

11. A method of driving a display device, the method comprising:

during first to kth touch sensing periods included in one frame period, determining whether first to s−

1th horizontal electrodes which are formed in parallel with a plurality of gate lines formed in a panel are touched by using a plurality of sensing signals received from the first to sth horizontal electrodes, in a touch panel which is built into the panel in an in-cell type, wherein s is a natural number more than k;

during at least two of k+1st to sth touch sensing periods included in the one frame period, determining whether the sth horizontal electrode which is formed in parallel with the plurality of gate lines formed in the panel is touched by using a plurality of sensing signals received from first to kth longitudinal electrodes crossing the first to sth horizontal electrodes, in the touch panel; and

during a plurality of image display periods which are executed between the touch sensing periods included in the one frame period, displaying an image in the panel including the touch panel,

wherein a driving voltage is alternatively supplied to the horizontal electrodes and the longitudinal electrodes in the one frame period, wherein the driving voltage is supplied to the longitudinal electrodes during the first period and the driving voltage is supplied to the horizontal electrodes during the second period, and wherein the first and second periods, which are different from each other, are touch sensing periods in the one frame period.

12. The method of claim 11, wherein,

the determining of whether the first to s−

1th horizontal electrodes are touched comprises, during the first to kth touch sensing periods, sequentially driving the driving voltage to the first to kth longitudinal electrodes, determining whether the first to s−

1st horizontal electrodes are touched, and

the determining of whether the sth horizontal electrode is touched comprises, during one of the k+1st to sth touch sensing periods, supplying the driving voltage to the sth horizontal electrode, determining whether the sth horizontal electrode is touched.