Touch apparatus and driving method

• US 8,810,526 B2
• Filed: 12/16/2010
• Issued: 08/19/2014
• Est. Priority Date: 12/18/2009
• Status: Active Grant

• Current Assignee: InnoLux Corporation
• Original Assignee: InnoLux Corporation
• Inventors: Shih, Po-Sheng, Chen, Po-Yang
• Primary Examiner(s): ABDIN, SHAHEDA A
• Application Number:
  US12/970,868
• Publication Number:
  US 20110148790A1
• Time in Patent Office: 1,342 Days
• Field of Search: 345173-176, 345/204, 345/214, 178/18.01, 178/18.06, 341/20, 156/272.8, 156/275.5
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers

Abstract

A touch apparatus includes a touch panel, voltage storage elements, a voltage supply unit, and a processing unit. The touch panel has electrodes respectively coupled to the voltage storage elements. When the voltage supply unit does not provide the voltage to the voltage storage element, the voltage storage element achieves a voltage balance within an energy storage time and stores a voltage of the corresponding electrode. The energy storage times of a part of the voltage storage elements at least partially overlap. The energy storage times of two the voltage storage elements respectively coupled to two adjacent electrodes do not overlap with each other. The processing unit is coupled to the electrodes and the voltage storage elements and adopts voltages stored in the voltage storage elements when the voltage balance is achieved.

Claims

1. A touch apparatus, comprising:

a touch panel including an upper substrate and a lower substrate, the upper and lower substrates respectively having a plurality of electrodes disposed thereon;

a plurality of voltage storage elements, each of the plurality of voltage storage elements coupled to each of the plurality of electrodes;

a voltage supply unit coupled to the plurality of electrodes and adapted to respectively provide and respectively not to provide a first voltage to the plurality of electrodes, wherein when the voltage supply unit does not provide the first voltage to the plurality of electrodes and one of the plurality of electrodes on the upper substrate electrically connects to one of the plurality of electrodes on the lower substrate, the voltage storage elements corresponding to the electrically connected electrodes are adapted to achieve a voltage balance within an energy storage time and store a second voltage of the electrically connected electrodes, the energy storage times of a part of the plurality of voltage storage elements at least partially overlap with each other, and the energy storage times of two of the plurality of voltage storage elements respectively coupled to two adjacent electrodes do not overlap with each other; and

a processing unit coupled to the plurality of electrodes and the voltage storage elements and adapted to adopt the second voltages stored in the voltage storage elements which correspond to the electrically connected electrodes when the voltage balance is achieved.

2. The touch apparatus as claimed in claim 1, wherein the voltage supply unit comprises a plurality of first switches respectively coupled between the plurality of electrodes and a bias voltage source, when the first switch is conducted, the bias voltage source provides the first voltage to the corresponding electrode, and when the first switch is not conducted, the bias voltage source does not provide the first voltage to the corresponding electrode.

3. The touch apparatus as claimed in claim 2, wherein the processing unit comprises:

a multiplexer coupled to the plurality of electrodes and the voltage storage elements;

an analog-to-digital converter coupled to the multiplexer, wherein the multiplexer is adapted to transmit the second voltages stored in the voltage storage elements after the energy storage time to the analog-to-digital converter, and the analog-to-digital converter is adapted to sequentially and respectively convert the second voltages into a plurality of digital signals; and

a digital signal processor coupled to the analog-to-digital converter and performing an operation according to the digital signals.

4. The touch apparatus as claimed in claim 1, further comprising:

a plurality of second switches respectively coupled between the plurality of electrodes and the corresponding voltage storage elements, wherein each of the second switches is switched off after the energy storage time of the corresponding voltage storage element.

5. The touch apparatus as claimed in claim 4, wherein the processing unit is adapted to respectively adopt the second voltages stored in the corresponding voltage storage elements after a time interval after at least a part of the second switches is switched off.

6. The touch apparatus as claimed in claim 1, further comprising a control unit controlling the voltage supply unit to provide and not to provide the first voltage to the plurality of electrodes and controlling a time point of the processing unit adopting the second voltages stored in the voltage storage elements.

7. The touch apparatus as claimed in claim 1, wherein each of the voltage storage elements comprises a parasitical capacitor coupled between the corresponding one of the plurality of electrodes and a ground, wherein the parasitical capacitor is coupled between the processing unit and the ground.

8. The touch apparatus as claimed in claim 1, wherein each of the voltage storage elements comprises a capacitor coupled between the corresponding one of the plurality of electrodes and a ground, wherein the capacitor is coupled between the processing unit and the ground.

9. The touch apparatus as claimed in claim 1, wherein the touch panel comprises a first conductive film and a second conductive film, and the plurality of electrodes are connected to at least one of the first conductive film and the second conductive film.

10. The touch apparatus as claimed in claim 9, wherein each of the first conductive film and the second conductive film is an anisotropic conductive film.

11. The touch apparatus as claimed in claim 1, wherein the touch panel is a resistive touch panel or a carbon nanotube touch panel.

12. A driving method, adapted to drive a touch apparatus, the driving method comprising:

respectively providing and respectively not providing a first voltage to a plurality of electrodes of the touch apparatus, wherein each of the plurality of electrodes is coupled to a plurality of voltage storage elements of the touch apparatus;

when the first voltage is not provided to the plurality of electrode and one of the plurality of electrodes on an upper substrate of the touch panel electrically connects to one of the plurality of electrodes on the lower substrate of the touch panel, letting the electrically connected electrodes and the voltage storage elements corresponding to the electrically connected electrodes achieve a voltage balance within an energy storage time and store a second voltage, wherein the energy storage times of a first part of the plurality of voltage storage elements at least partially overlap with each other, and the energy storage times of two of the plurality of voltage storage element respectively coupled to two adjacent electrodes do not overlap with each other; and

adopting the second voltages stored in the voltage storage elements when the voltage balance is achieved;

converting the second voltage stored in the voltage storage elements when the voltage balance is achieved into a plurality of digital signals; and

performing an operation according to the digital signals.

13. The driving method as claimed in claim 12, wherein the step of adopting the second voltage stored in the voltage storage elements when the voltage balance is achieved comprising:

after the corresponding energy storage time, adopting the second voltages stored in the voltage storage elements when the voltage balance is achieved.

14. The driving method as claimed in claim 12, wherein the step of adopting the second voltage stored in the voltage storage elements when the voltage balance is achieved comprising:

after the corresponding energy storage time, adopting the second voltage stored in a second part of the voltage storage elements when the voltage balance is achieved; and

after a time interval after the corresponding energy storage time, adopting the second voltages stored in the second part of the voltage storage elements when the voltage balance is achieved.

15. The driving method as claimed in claim 12, wherein the step of respectively providing and respectively not providing the first voltage to the plurality of electrodes of the touch apparatus comprises:

within the energy storage time of the voltage storage element corresponding to each of the plurality of electrodes, not providing the first voltage to the electrode; and

except the energy storage time of the voltage storage element corresponding to each of the plurality of electrodes, providing the first voltage to the electrode.