TOUCH SENSOR AND LIQUID CRYSTAL DISPLAY INCLUDING THE SAME

• US 20170108973A1
• Filed: 05/24/2016
• Published: 04/20/2017
• Est. Priority Date: 10/20/2015
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: KIM, Sang Mi, GOH, Joon Chul, LIM, Kyoung Ho
• Granted Patent: US 10,209,803 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133394 Piezoelectric elements associated with the cells
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• 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

Abstract

There are provided a touch sensor and a liquid crystal display including the same. A touch sensor includes a plurality of driving electrodes, a plurality of sensing electrodes intersecting the driving electrodes, a plurality of piezoelectric materials disposed between the driving electrodes and the sensing electrodes at intersection points of the driving electrodes and the sensing electrodes, and a touch controller for detecting a touch position and a touch pressure by using sensing signals output from the sensing electrodes.

Claims

1. A touch sensor comprising:

a plurality of driving electrodes;

a plurality of sensing electrodes intersecting the driving electrodes;

a plurality of piezoelectric materials disposed between the driving electrodes and the sensing electrodes at intersection points of the driving electrodes and the sensing electrodes; and

a touch controller configured to detect a touch position and a touch pressure by using sensing signals output from the sensing electrodes.

2. The touch sensor of claim 1, wherein the touch controller includes:

a touch position detector configured to detect the touch position by using alternating current (AC) components of the sensing signals; and

a touch pressure detector configured to detect the touch pressure by using direct current (DC) components of the sensing signals.

3. The touch sensor of claim 2, wherein the touch controller further includes a plurality of AC bypass capacitors disposed between the sensing electrodes and the touch position detector, the plurality of AC bypass capacitors selectively transmitting the AC components of the sensing signals to the touch position detector.

4. The touch sensor of claim 3, wherein the touch pressure detector includes:

an analog-digital converter (ADC) receiving the DC components of the sensing signal and configured to convert the DC components of the sensing signals into digital data; and

a converting unit connected to the ADC and configured to convert the digital data output from the ADC into touch pressure information.

5. The touch sensor of claim 4, wherein the plurality of piezoelectric materials are disposed on a plurality of column spacers, respectively.

6. The touch sensor of claim 5, wherein the plurality of piezoelectric materials and the plurality of column spacers are completely overlap in a plan view.

7. The touch sensor of claim 2, wherein the touch pressure detector includes:

an analog-digital converter (ADC) receiving the DC components of the sensing signal and configured to convert the DC components of the sensing signals into digital data; and

a converting unit connected to the ADC and configured to convert the digital data output from the ADC into touch pressure information.

8. The touch sensor of claim 2, wherein the touch controller further includes a driving signal supply unit configured to supply driving signals to the driving electrodes.

9. The touch sensor of claim 1, wherein the plurality of piezoelectric materials are disposed on a plurality of column spacers, respectively.

10. The touch sensor of claim 6, wherein the plurality of piezoelectric materials and the plurality of column spacers are completely overlap in a plan view.

11. A liquid crystal display, comprising:

a first substrate and a second substrate opposite to each other;

a plurality of driving electrodes formed on the first substrate;

a black matrix formed under the second substrate;

a plurality of column spacers disposed under the black matrix, the plurality of column spacers extending toward the first substrate;

a plurality of sensing electrodes formed over the column spacers and the black matrix, the plurality of sensing electrodes intersecting the driving electrodes;

a plurality of piezoelectric materials disposed between the driving electrodes and the sensing electrodes at intersection points of the driving electrodes and the sensing electrodes; and

a touch controller configured to detect a touch position and a touch pressure by using sensing signals output from the sensing electrodes.

12. The liquid crystal display of claim 11, wherein the plurality of driving electrodes overlap the black matrix.

13. The liquid crystal display of claim 11, further comprising a liquid crystal layer disposed between the first substrate and the second substrate.

14. The liquid crystal display of claim 11, wherein the touch controller includes:

a touch position detector configured to detect the touch position by using AC components of the sensing signals; and

a touch pressure detector configured to detect the touch pressure by using DC components of the sensing signals.

15. The liquid crystal display of claim 14, wherein the touch controller further includes a plurality of AC bypass capacitors disposed between the sensing electrodes and the touch position detector, the plurality of AC bypass capacitors selectively transmitting the AC components of the sensing signals to the touch position detector.

16. The liquid crystal display of claim 14, wherein the touch pressure detector includes:

an ADC receiving the DC components of the sensing signal and configured to convert the DC components of the sensing signals into digital data; and

a converting unit connected to the ADC and configured to convert the digital data output from the ADC into touch pressure information.

17. The liquid crystal display of claim 14, wherein the touch controller further includes a driving signal supply unit configured to supply driving signals to the driving electrodes.

18. The touch sensor of claim 11, wherein the plurality of piezoelectric materials are disposed on the plurality of column spacers, respectively.

19. The touch sensor of claim 18, wherein the plurality of piezoelectric materials and the plurality of column spacers are completely overlap in a plan view.