TOUCH SENSING DISPLAY DEVICE AND DRIVING METHOD THEREOF

• US 20090146964A1
• Filed: 07/03/2008
• Published: 06/11/2009
• Est. Priority Date: 12/10/2007
• Status: Abandoned Application

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Lee, Joo-Hyung, Park, Jong-Woung, Uh, Kee-Han, Kim, Hyung-Guel, Lee, Sung-Woo, Ma, Won-Seok, Jeon, Byung-Ki
• Application Number:
  US12/167,733
• Publication Number:
  US 20090146964A1
• Time in Patent Office: Days
• US Class Current: 345/173
• 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 3/047 using sets of wires, e.g. crossed wires

Abstract

In a touch sensing display device, a plurality of sensor scanning lines extend in a first direction and sequentially receive a first voltage, and a plurality of sensor data lines extend in a second, different, direction. A plurality of sensing elements are formed in regions defined by the sensor scanning lines and the sensor data lines, and each sensing element transmits the first voltage from a corresponding sensor scanning line to a corresponding sensor data line responsive to an external touch. A sensing signal processor converts voltages of the sensor data lines into sensing data, and, a touch determining unit processes the sensing data corresponding to the sensor scanning lines by at least one scanning line to determine positions of touch regions generated during at least one frame.

Claims

1. A display device comprising:

a plurality of sensor scanning lines extending in a first direction and sequentially receiving a first voltage;

a plurality of sensor data lines extending in a second, different, direction;

a plurality of sensing elements respectively formed in regions defined by the sensor scanning lines and the sensor data lines, and configured to transmit the first voltage from an associated sensor scanning line among the plurality of sensor scanning lines to an associated sensor data line among the plurality of sensor data lines according to an external touch;

a sensing signal processor configured to convert voltages of the sensor data lines into sensing data; and

a touch determining unit configured to determine positions of touch regions receiving external touches during at least one frame by processing sensing data for at least one sensor scanning line, wherein sensing data for at least one sensor scanning line is generated by sensing elements connected to one of the plurality of scanning lines.

2. The display device of claim 1, further comprising:

a plurality of sensor gate lines;

an sensor scanning driver configured to sequentially transmit a gate-on voltage to the sensor gate lines;

a plurality of switching elements, each switching element having an input terminal corresponding to a signal line for supplying the first voltage, a control terminal corresponding to the sensor gate line, and an output terminal corresponding to the sensor scanning line, wherein each switching element is configured to be turned on in response to the gate-on voltage transmitted to the control terminal.

3. The display device of claim 1, wherein the touch determining unit comprises:

a sensing data reader configured to receive and store the sensing data of at least one scanning line from the sensing signal processor; and

a touch position determining unit configured to read the sensing data of at least one scanning line stored in the sensing data reader to determine the positions of the touch regions, wherein the sensing data reader is configured to receive and store the sensing data of at least one next scanning line from the sensing signal processor after the touch position determining unit reads the sensing data of the at least one scanning line.

4. The display device of claim 3, wherein the touch position determining unit is configured to determine the number of touch regions generated during at least one frame and the position of each touch region.

5. The display device of claim 1, wherein the sensing signal processor is configured to maintain the voltage of a sensor data line not receiving the first voltage with a second voltage different from the first voltage, generate a sensing data with a first value when the sensor data line has the first voltage, and generate a sensing data to a second value when the sensor data line has the second voltage.

6. The display device of claim 5, wherein the sensing signal processor includes a plurality of resistors, at least one of which is connected between each of the sensor data lines and a voltage source supplying the second voltage.

7. The display device of claim 5, wherein the touch determining unit is configured to determine a first start position and a first end position in the column direction of each touch region generated during at least one frame, and determine a representative value from the first start position and the first end position as a position in the second direction.

8. The display device of claim 7, wherein the touch determining unit is configured to determine a representative position in each scanning line corresponding to each touch region, and determine a representative value of the representative positions in the sensor scanning lines corresponding to each touch region as a position in the first direction.

9. The display device of claim 8, wherein the touch determining unit is configured to determine a second start position and a second end position in each scanning line of each touch region, and determine a representative value from the second start position and the second end position as the representative position of each scanning line.

10. The display device of claim 9, wherein the representative value is the average value.

11. The display device of claim 9, wherein the touch determining unit is configured to determine a position at which the sensing data is changed from the second value to the first value in each scanning line as the second start position, and determines a position at which the sensing data is changed from the first value to the second value as the second end position.

12. The display device of claim 8, wherein the touch position determining unit is configured to search each scanning line of sensing data to determine the first start position and the first end position of each touch region.

13. The display device of claim 12, wherein the touch position determining unit is configured to determine a position of a scanning line at which the representative position is first determined in each touch region as the first start position.

14. The display device of claim 12, wherein the touch position determining unit is configured to determine a previous scanning line as the first end position when the sensing data of a current scanning line corresponding to the representative position of the previous scanning line in each touch region is the second value.

15. The display device of claim 12, wherein when the first end position is not determined in each touch region and at least one among the sensing data of a current scanning line respectively corresponding to the second start position, the second end position, and the representative position of a previous scanning line is the first value, the touch position determining unit is configured to set the representative position of the current scanning line to be within the same touch region as the representative position of the previous scanning line.

16. A method of driving a display device including a plurality of sensor scanning lines extending in a first direction, a plurality of sensor data lines extending in a second direction, and a plurality of sensing elements formed in the regions defined by the sensor scanning lines and the sensor data lines and connected to a corresponding sensor scanning line and a corresponding sensor data line, the method comprising:

sequentially applying a reference voltage to the sensor scanning lines;

transmitting the reference voltage from a sensor scanning line connected to a sensing element receiving an external touch to a sensor data line connected to the sensing element;

converting voltages of the sensor data lines into sensing data; and

determining positions of touch regions generated during one frame by processing the sensing data by one scanning line.

17. The method of claim 16, wherein the conversion of the voltages comprises:

generating a sensing data having a first value when the voltage of a sensor data line is the reference voltage; and

generating a sensing data having a second value when the voltage of a sensor data is not the reference voltage.

18. The method of claim 17, wherein the determination of the positions comprises:

searching the sensing data sequentially in the first direction to detect a start of a first touch region;

determining a position of the first touch region in the second direction; and

determining a position of the first touch region in the first direction.

19. The method of claim 18, wherein the determination of the position in the second direction comprises:

determining a first start position and a first end position of the first touch region in the second direction; and

determining a representative value of the first start position and the first of the first touch region end position as the position in the second direction; and

further wherein the determination of the position in the first direction comprises;

determining a representative position of the first touch region in each scanning line; and

determining a representative value of the representative positions in scanning lines of the first touch region as the position of the first touch region in the first direction.

20. The method of claim 19, wherein the determination of the representative position comprises:

determining a second start position and a second end position of the first touch region in each scanning line; and

determining a representative value of the second start position and the second end position as the representative position.

21. The method of claim 20, wherein the determination of the second start position and the second end position comprises:

determining a position at which the sensing data is changed from the second value to the first value in each scanning line of the first touch region as the second start position; and

determining a position at which the sensing data is changed from the first value to the second value in each scanning line of the first touch region as the second end position.

22. The method of claim 20, wherein the determination of the first start position and the first end position comprises determining a scanning line at which the representative position is firstly determined in the first touch region as the first start position.

23. The method of claim 20, wherein the determination of the first start position and the first end position comprises determining a previous scanning line as the first end position when the sensing data of a current scanning line corresponding to the representative position of the previous scanning line in the first touch region is the second value.

24. The method of claim 20, wherein the determination of the positions further comprises determining the representative position of a current scanning line to be included in the first touch region if at least one among the sensing data of the current scanning line corresponding to the second start position, the second end position, and the representative position of a previous scanning line has the first value when the first end position is not determined in the first touch region.

25. The method of claim 20, wherein the determination of the positions further comprises determining the representative position of a current scanning line to be within a second touch region that is different from the first touch region if the sensing data of the current scanning line corresponds to the second start position, the second end position, and the representative position of a previous scanning line have the second value and the first end position is not determined in the first touch region.