Touch sensitive display device, and driving method thereof

• US 20080314652A1
• Filed: 04/01/2008
• Published: 12/25/2008
• Est. Priority Date: 06/21/2007
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Group)
• Original Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Inventors: Park, Cheol-Woo, Kim, Joo-Young, Choi, Uk-Chul
• Granted Patent: US 8,081,167 B2
• Time in Patent Office: Days
• US Class Current: 178/18.01
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/042 by opto-electronic means

Abstract

A display device having a contact sensing function, and a driving method thereof are disclosed in one embodiment. The driving method of a display device includes reading sense data signals of a current sensing unit row, determining whether the sense data signals are included in a contactable range and converting the sense data signals into preliminary signals that each have a predetermined value based on the determination result, determining whether a sensed area (an X axis sensed area) in an X axis direction exists using the preliminary signals, determining whether the X axis sensed area is effective when the X axis sensed area exists, determining whether a sensed area (a Y axis sensed area) in a Y axis direction exists when the X axis sensed area is effective, determining whether the Y axis sensed area is effective when the Y axis sensed area exists, determining a contact position when the Y axis sensed area is effective, and reading sense data signals of a next sensing unit row when the X axis sensed area or the Y axis sensed area is not effective.

Claims

1. A driving method of a display device, comprising:

reading sense data signals of a first sensing unit row, the sense data signals being sequentially input;

determining whether the sense data signals are included in a contactable range;

converting the sense data signals into preliminary signals, each of which has a predetermined value based on whether the sense data signals are included in the contactable range;

determining whether an X axis sensed area exists using the preliminary signals;

determining whether the X axis sensed area is effective when the X axis sensed area exists;

determining whether a Y axis sensed area exists when the X axis sensed area is effective;

determining whether the Y axis sensed area is effective when the Y axis sensed area exists;

determining a contact position when the X axis sensed area is effective.

reading sense data signals of a second sensing unit row when the X axis sensed area or the Y axis sensed area is not effective.

2. The driving method of claim 1, wherein converting the sense data signals into preliminary signals comprises:

converting the sense data signals included in a first range into preliminary signals having a first value; and

converting the sense data signals included in a second range into preliminary signals having a second value,

wherein the first range and the second range differ.

3. The driving method of claim 2, wherein determining whether the X axis sensed area exists comprises:

determining that the X axis sensed area starts when the value of the preliminary signal is changed from the first value or the second value to the second value or the first value, respectively; and

determining that the X axis sensed area finishes when the value of the preliminary signal is changed from the second value or the first value to the first value or the second value, respectively.

4. The driving method of claim 2, wherein the preliminary signals output from sensing units included in the X axis sensed area have the same values.

5. The driving method of claim 3, wherein determining whether the X axis sensed area is effective comprises:

determining whether the X axis sensed area exists;

calculating a row length and determining whether the row length is included in a first effective range, when the X axis sensed area exists;

calculating a first center position value when the row length is included in the first effective range;

determining whether a center start position value exists;

storing the calculated first center position value as the center start position value when the center start position value does not exist and storing a number of the first sensing unit row as a Y axis start position value;

calculating a distance between the center start position value and the first center start position value when the center start position value exists;

determining whether the distance is included in a second effective range; and

storing the number of the first sensing unit row as a Y axis end position value when the distance is included in the second effective range and storing the first center position value as the center start position value.

6. The driving method of claim 5, wherein determining whether the X axis sensed area is effective further comprises:

determining whether the Y axis sensed area exists when the X axis sensed area does not exist, when the row length is not included in the first effective range, or whether the distance is not included in the second effective range.

7. The driving method of claim 6, wherein determining whether the X axis sensed area is effective further comprises:

outputting a signal indicating a state in which the row length is not included in the first effective range or a state in which the distance is not included in the second effective range.

8. The driving method of claim 5, wherein determining whether the Y axis sensed area is effective comprises:

determining whether the Y axis end value exists;

calculating a column length based on the Y axis start position value and the Y axis end position value when the Y axis end position value exists;

determining whether the calculated column length is included within a third effective range;

determining the contact position when the calculated column length is included in the third effective range; and

initializing variables when the calculated column length is not included in the third effective range.

9. The driving method of claim 8, wherein determining the contact position comprises:

defining the center start position value as an X axis coordinate of the contact position;

calculating a Y axis coordinate of the contact position based on the Y axis start position value and the Y axis end position value; and

initializing variables.

10. The driving method of claim 9, wherein determining the contact position further comprises defining a center position value of the Y axis start position value and the Y axis end position value as the Y axis coordinate of the contact position.

11. The driving method of claim 6, wherein the first effective range is the same as the second effective range.

12. A display device, comprising:

a display panel having a plurality of sensing units and a plurality of sense data lines connected to the sensing units;

a sense signal processor connected to the display panel, the sense signal processor receiving analog sense data signals from the sense data lines, and converting the analog sense data signals to digital sense data signals; and

a contact position determiner connected to the sense signal processor for determining a contact position based on the digital sense data signals,

wherein the contact position determiner comprises;

a processor reading the sense data signals of a first sensing unit row, the sense data signals being sequentially input, and determining whether the sense data signals are included in a contactable range to convert the sense data signals into preliminary signals; and

an operator determining whether an X axis sensed area exists, determining whether the X axis sensed area is effective when the X axis sensed area exists, determining whether a Y axis sensed area exists when the X axis sensed area is effective, determining whether the Y axis sensed area is effective when the Y axis sensed area exists, determining a contact position when the Y axis sensed area is effective, and reading sense data signals of a second sensing unit row when the X axis sensed area or the Y axis sensed area is not effective.

13. The display device of claim 12, wherein each of the digital sense data signals has a predetermined number of bits, and the processor converts the digital sense data signals having values that are included in a predetermined range to preliminary signals having a first value, and converts the digital sense data signals having values that are not included in a predetermined range to preliminary signals having a second value.

14. The display device of claim 13, wherein each of the preliminary signals is a one-bit signal.

15. The display device of claim 13, wherein the X axis sensed area starts when the value of the preliminary signal is changed from the second value to the first value, and finishes when the value of the preliminary signal is changed from the first value to the second value.

16. The display device of claim 13, wherein the operator:

calculates a row length and determines whether the row length is included in a first effective range, when the X axis sensed area exists;

calculates a first center position value when the row length is included within the first effective range;

determines whether a center start position value exists, stores the calculated first center position value as the center start position value when the center start position value does not exist, and stores a number of the current sensing unit row as a Y axis start position value;

calculates a distance between the center start position value and the calculated first center start position value when the center start position value exists;

determines whether the distance is included within a second effective range; and

stores the number of the current sensing unit row as a Y axis end position value when the distance is included within the second effective range and stores the calculated first center position value as the center start position value.

17. The display device of claim 16, wherein the operator determines whether the Y axis sensed area exists when the X axis sensed area does not exist, when the row length is not included in the first effective range, or whether the distance is not included in the second effective range.

18. The display device of claim 17, wherein the operator determines whether the Y axis end value exists, calculates a column length based on the Y axis start position value and the Y axis end position value when the Y axis end position value exists, determines whether the calculated column length is included in a third effective range, and determines the contact position when the calculated column length is included in the third effective range.

19. The display device of claim 18, wherein the operator initializes variables when the calculated column length is not included in the third effective range.