Method for Transmitting and Detecting Touch Sensing Signals and Touch Device Using the Same

• US 20130076691A1
• Filed: 09/27/2012
• Published: 03/28/2013
• Est. Priority Date: 09/28/2011
• Status: Active Grant

• Current Assignee: Hung-Ta Liu
• Original Assignee: Hung-Ta Liu
• Inventors: Liu, Hung-Ta
• Granted Patent: US 9,046,976 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• 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: G06F 3/046 by electromagnetic means

Abstract

A method for transmitting and detecting touch sensing signals in a touch device having a set of parallel conducting lines includes: providing a work signal and a touch sensing signal to a selected portion of the conducting lines that serve as touch sensing lines and that cooperate to define a touch sensing area; and detecting the touch sensing lines to obtain a detecting signal that corresponds to the touch sensing signal and that indicates occurrence of a touch event, so as to determine at least one of a position and an intensity of the touch event. For each of the touch sensing lines, the work signal is provided during a first time interval and the touch sensing signal is provided during a second time interval.

Claims

1. A method for transmitting and detecting touch sensing signals in a touch device having a set of parallel conducting lines, said method comprising:

a) providing a work signal and a touch sensing signal to a selected portion of the conducting lines that serve as touch sensing lines and that cooperate to define a touch sensing area,

wherein, for each of the touch sensing lines, the work signal is provided during a first time interval and the touch sensing signal is provided during a second time interval; and

b) detecting the touch sensing lines to obtain a detecting signal that corresponds to the touch sensing signal and that indicates occurrence of a touch event, so as to determine at least one of a position and an intensity of the touch event.

2. The method as claimed in claim 1, wherein, for each of the touch sensing lines, the first and second time intervals are non-overlapping time intervals.

3. The method as claimed in claim 2, wherein, in step a),

for each of the touch sensing lines, a reference voltage signal is further provided during a third time interval that occurs before the second time interval and that does not overlap with the first time interval.

4. The method as claimed in claim 2, wherein, for each of the touch sensing lines, the touch sensing signal is mixed with a reference voltage signal.

5. The method as claimed in claim 1, wherein, for each of the touch sensing lines, the touch sensing signal is mixed with the work signal and the first and second time intervals overlap.

6. The method as claimed in claim 1, wherein the touch device is a touch display, and the set of conducting lines is one of a set of data lines and a set of scan lines of the touch display.

7. The method as claimed in claim 1, wherein step a) includes coupling and uncoupling each of the touch sensing lines to one of a ground, a conductor, and a capacitor during a third time interval that occurs before the second time interval and that does not overlap with the first time interval.

8. The method as claimed in claim 1, wherein the touch device is a touch display including a switch circuit coupled to the touch sensing lines, the touch sensing lines being switchable to serve as common electrodes of the touch display via the switch circuit.

9. The method as claimed in claim 1, wherein the touch device is a touch display selected from a liquid crystal display including a liquid crystal layer and another set of parallel conducting lines that cross and cooperate with said one set of parallel conducting lines to drive the liquid crystal layer, a liquid-crystal-on-silicon microdisplay, an electrowetting display, an electrophoretic display, and an organic light-emitting diode display.

10. The method as claimed in claim 1, wherein the touch device is a touch display, the first time interval is a display interval of the touch display, and the second time interval is included in a blanking interval of the touch display.

11. A method for transmitting and detecting touch sensing signals in a touch device having a set of conducting lines and a set of touch sensing lines, said method comprising:

i) providing a work signal to the set of conducting lines;

ii) providing a reference voltage signal to one of the set of conducting lines and the set of touch sensing lines;

iii) providing a touch sensing signal to the set of touch sensing lines; and

iv) detecting the touch sensing lines to obtain a detecting signal that corresponds to the touch sensing signal and that indicates occurrence of a touch event, so as to determine at least one of a position and an intensity of the touch event.

12. The method as claimed in claim 11, wherein, in step ii), the reference voltage signal is provided to the set of touch sensing lines, and in step iii), the touch sensing signal is mixed with the reference voltage signal such that steps ii) and iii) occur at the same time.

13. The method as claimed in claim 11, wherein, in step ii), the reference voltage signal is provided to all of the touch sensing lines simultaneously, and in step iii), the touch sensing signal is respectively provided to the touch sensing lines after step ii).

14. The method as claimed in claim 13, wherein steps i) and ii) occur at the same time.

15. The method as claimed in claim 13, further comprising providing the reference voltage signal to the touch sensing lines while the work signal is provided to the conducting lines,

wherein, in step ii), the reference voltage signal is provided to the conducting lines, and steps ii) and iii) occur at the same time.

16. The method as claimed in claim 13, wherein step ii) follows step i), the reference voltage signal is provided to the set of touch sensing lines in step ii), and step iii) follows step ii).

17. The method as claimed in claim 16, further comprising providing the reference voltage signal to the conducting lines while either of the reference voltage signal and the touch sensing signal is provided to the touch sensing lines.

18. The method as claimed in claim 11, wherein:

in step ii), the reference voltage signal is provided to the touch sensing lines in sequence, and

in step iii), the touch sensing signal is provided to the touch sensing lines in sequence after step ii).

19. The method as claimed in claim 11, wherein:

in step ii), the reference voltage signal is provided to the touch sensing lines in sequence; and

in step iii), the touch sensing signal is provided to one of the touch sensing lines immediately after providing the reference voltage signal to said one of the touch sensing lines.

20. The method as claimed in claim 11, wherein step iii) includes coupling and uncoupling each of the touch sensing lines to one of a ground, a conductor, and a capacitor before providing the touch sensing signal to the touch sensing lines.

21. The method as claimed in claim 11, wherein the touch device is a touch display selected from a liquid crystal display including a liquid crystal layer and another set of conducting lines that cross and cooperate with said one set of conducting lines to drive the liquid crystal layer, a liquid-crystal-on-silicon microdisplay, an electrowetting display, an electrophoretic display, and an organic light-emitting diode display.

22. The method as claimed in claim 21, wherein the touch device is the liquid crystal display further includes a backlight module serving as a light source, said method further comprising one of dimming light output of the backlight module and turning off the backlight module simultaneous with step ii) when the reference voltage signal is provided to the set of conducting lines.

23. The method as claimed in claim 11, wherein:

the touch device is a touch display including a liquid crystal display (LCD), and a capacitive touch sensing layer disposed on the LCD, the conducting lines being included in the LCD, the touch sensing lines being included in the capacitive touch sensing layer;

in step ii), the reference voltage signal is provided to the conducting lines after step i); and

in step iii), the touch sensing signal is provided to the touch sensing lines after step ii).

24. The method as claimed in claim 23, wherein the LCD further includes a backlight module serving as a light source, said method further comprising one of dimming light output of the backlight module and turning off the backlight module simultaneous with step ii).

25. The method as claimed in claim 23, wherein step iii) includes coupling and uncoupling each of the touch sensing lines to one of a ground, a conductor, and a capacitor before providing the touch sensing signal to the touch sensing lines.

26. A method for transmitting and detecting touch sensing signals in a capacitive touch sensing circuit having a set of touch sensing lines, said method comprising:

coupling and uncoupling each of the touch sensing lines to one of a ground and a capacitor;

providing a touch sensing signal to the touch sensing lines; and

detecting the touch sensing lines to obtain a detecting signal that corresponds to the touch sensing signal and that indicates occurrence of a touch event, so as to determine at least one of a position and an intensity of the touch event.