LIQUID CRYSTAL DISPLAY DEVICE

• US 20130328757A1
• Filed: 06/07/2013
• Published: 12/12/2013
• Est. Priority Date: 06/08/2012
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display Incorporated
• Inventors: MATSUMOTO, Shuuichirou, AOKI, Yoshinori
• Granted Patent: US 9,378,699 B2
• Time in Patent Office: Days
• US Class Current: 345/87
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/134336 Matrix
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• 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 3/0443 using a single layer of sensing electrodes
• 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 3/3696 Generation of voltages supplied to electrode drivers

Abstract

In a liquid crystal display device with a touch panel function, a second substrate has detection electrodes of a touch panel, each pixel has a pixel electrode and a counter electrode, the counter electrode is divided into a plurality of blocks, and the counter electrodes of the respective divided blocks are shared to the respective pixels of a plurality of display lines side by side, the counter electrodes of the respective divided blocks is also used as scanning electrodes of the touch panel, and a driver circuit is provided to apply a counter voltage and a touch panel scanning voltage to the counter electrodes of the respective divided blocks, and the driver circuit can adjust a supply start timing of the touch panel scanning voltage to be applied to the counter electrodes of the respective divided blocks.

Claims

1. A liquid crystal display device including a liquid crystal display panel having liquid crystal held between a first substrate and a second substrate,

the liquid crystal display panel comprising:

detection electrodes of a touch panel which are arranged on the second substrate;

pixel electrodes which are arranged in each of a plurality of pixels arranged in a matrix and a counter electrode divided into a plurality of blocks; and

a driver circuit that applies a counter voltage and a touch panel scanning voltage to a counter electrode of the respective divided blocks,

wherein the counter electrode of the respective divided blocks is shared to the respective pixels of a plurality of display lines side by side, and is also used as scanning electrodes of the touch panel, and

wherein the driver circuit can adjust a supply start timing of the touch panel scanning voltage to be applied to the counter electrode of the respective divided blocks.

4. The liquid crystal display device according to claim 1,

wherein the first substrate has a plurality of video lines that inputs a video voltage to the respective images, and

wherein the driver circuit applies the touch panel scanning voltage to the counter electrode of the respective divided blocks at a time point later than a voltage transition timing of the video voltage on the video lines by a given time.

5. The liquid crystal display device according to claim 1,

wherein the first substrate has a plurality of scan lines that inputs a scanning voltage to the respective images, and

wherein the driver circuit applies the touch panel scanning voltage to the counter electrode of the respective divided blocks at a time point later than a rise time of the scanning voltage, or a fall time of the scanning voltage by a given time.

6. The liquid crystal display device according to claim 1,

wherein the driver circuit has a timing setting register, and

wherein the driver circuit applies the touch panel scanning voltage to the counter electrode of the respective divided blocks at a later time point by a given time on the basis of data set in the timing setting register.

10. The liquid crystal display device according to claim 1,

wherein each of the counter electrodes is shared to the respective pixels of one display line on the first substrate, and

wherein the respective counter electrodes on a plurality of display lines side by side are electrically connected to each other on the first substrate, and divided in block units.

11. The liquid crystal display device according to claim 1, further comprising:

a counter electrode selector circuit that selects any one of the counter electrodes of the respective divided blocks,

wherein the counter electrode selector circuit includes;

an address decoder circuit that selects any counter electrode of the respective divided blocks for a given period; and

a selector circuit that applies the touch panel scanning voltage to the counter electrode of the block selected by the address decoder circuit, and applies the counter voltage to the counter electrodes of the blocks not selected by the address decoder circuit.

12. The liquid crystal display device according to claim 11,

wherein the counter electrode selector circuit is formed on the first substrate, and incorporated into the liquid crystal display panel.

13. The liquid crystal display device according to claim 12,

wherein the first substrate includes:

a plurality of scanning lines that inputs the scanning voltage to the respective pixels; and

a scanning line driver circuit that applies the scanning voltage to the plurality of scanning lines,

wherein the plurality of pixels arranged in the matrix configures a display area, and

wherein the counter electrode selector circuit is arranged between the scanning line driver circuit and the display area.

14. The liquid crystal display device according to claim 13,

wherein the scanning line driver circuit is formed on the first substrate, and incorporated into the liquid crystal display panel.

15. The liquid crystal display device according to claim 1,

wherein the driver circuit applies the video voltage to the plurality of video lines.

2. A liquid crystal display device including a liquid crystal display panel having liquid crystal held between a first substrate and a second substrate,

the liquid crystal display panel comprising:

detection electrodes of a touch panel which are arranged on the second substrate;

pixel electrodes which are arranged in each of a plurality of pixels arranged in a matrix and a counter electrode divided into a plurality of blocks; and

a driver circuit that applies a counter voltage and a touch panel scanning voltage to a counter electrode of the respective divided blocks,

wherein the counter electrode of the respective divided blocks is shared to the respective pixels of a plurality of display lines side by side, and is also used as scanning electrodes of the touch panel, and

wherein the driver circuit can adjust a pulse width of the touch panel scanning voltage to be applied to the counter electrode of the respective divided blocks.

7. The liquid crystal display device according to claim 2,

wherein the driver circuit has a scanning pulse width register, and

wherein the driver circuit determines the pulse width of the touch panel scanning voltage to be applied to the counter electrode of the respective divided blocks, on the basis of data set in the scanning pulse width register.

3. A liquid crystal display device including a liquid crystal display panel having liquid crystal held between a first substrate and a second substrate,

the liquid crystal display panel comprising:

detection electrodes of a touch panel which are arranged on the second substrate;

pixel electrodes which are arranged in each of a plurality of pixels arranged in a matrix and a counter electrode divided into a plurality of blocks; and

a driver circuit that applies a counter voltage and a touch panel scanning voltage to a counter electrode of the respective divided blocks,

wherein the counter electrode of the respective divided blocks is shared to the respective pixels of a plurality of display lines side by side, and is also used as scanning electrodes of the touch panel, and

wherein the driver circuit can adjust a supply start timing of the touch panel scanning voltage to be applied to the counter electrode of the respective divided blocks, and can adjust a pulse width of the touch panel scanning voltage to be applied to the counter electrode of the respective divided blocks.

8. A liquid crystal display device including a liquid crystal display panel having liquid crystal held between a first substrate and a second substrate,

the liquid crystal display panel comprising:

detection electrodes of a touch panel which are arranged on the second substrate;

pixel electrodes which are arranged in each of a plurality of pixels arranged in a matrix and a counter electrode divided into a plurality of blocks; and

a driver circuit that applies a counter voltage and a touch panel scanning voltage to a counter electrode of the respective divided blocks,

wherein the counter electrode of the respective divided blocks is shared to the respective pixels of a plurality of display lines side by side, and is also used as scanning electrodes of the touch panel, and

wherein the driver circuit digitally adds a pulse voltage having a desired amplitude value to the counter voltage to generate the touch panel scanning voltage to be applied to the counter electrode of the respective divided blocks.

9. The liquid crystal display device according to claim 8,

wherein the driver circuit comprises:

a scanning voltage pulse width setting register;

a counter voltage register;

an arithmetic logic circuit that receives data set in the scanning voltage pulse width setting register, and data set in the counter voltage register;

a scanning voltage setting register that sets data output from the arithmetic logic circuit;

a counter voltage generator circuit that generates the counter voltage on the basis of data set in the counter voltage register; and

a touch panel scanning voltage generator circuit that generates the touch panel scanning voltage on the basis of data set in the scanning voltage setting register.