DETECTING METHOD AND DEVICE FOR TOUCH SCREEN

• US 20130321331A1
• Filed: 05/17/2013
• Published: 12/05/2013
• Est. Priority Date: 05/18/2012
• Status: Active Grant

• Current Assignee: eGalax_eMPIA Technology Inc.
• Original Assignee: eGalax_eMPIA Technology Inc.
• Inventors: CHANG, CHIN-FU
• Granted Patent: US 9,665,231 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• 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 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/044 by capacitive means
• 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 3/047 using sets of wires, e.g. crossed wires

Abstract

One driving electrode or one set of driving electrode of a touch screen are designated as a base electrode or base electrodes. When the base electrode or base electrodes are provided by a driving signal, the detected signal from the sensing electrodes is designated as a level signal. The level signal is used to adjust the detected signal when other non-base electrodes are provided by the driving signal, whereby the detected image from the touch screen can be leveled.

Claims

1. A detecting device for touch screen, comprising:

a touch screen comprising a plurality of parallel driving electrodes and a plurality of parallel detecting electrodes is provided, wherein the driving electrodes and the detecting electrodes cross each other at intersections;

a driving circuit, providing a driving signal to one driving electrode or one set of driving electrodes, wherein one driving electrode or one set of driving electrodes are designated as one base electrode or one set of base electrodes, and the others of the driving electrodes are not designated as base electrodes;

a detecting circuit, by signals of at least one detecting electrode, generating an evaluating signal for the driving electrodes, to which the driving signal is provided, based on one of a plurality of parameter sets when the driving signal is provided each time; and

a control circuit selects one of the parameter sets as an initial parameter set of the base electrode so as to designate the evaluated signal, which is produced by detecting circuit based on the initial parameter set, as a level signal, and the initial parameter set of each one or each set of the non-base electrode is selected from the mentioned parameter set, wherein the evaluated signal of each one or each set of the non-base electrode based on the initial parameter set is the closet one to the level signal comparing to other evaluated signals produced by other parameter sets.

2. The detecting device of claim 1, wherein the control circuit controls the detecting circuit to produce the evaluated signal of the base electrode produced based on one of the parameter sets in order, and the parameter set producing the largest evaluated signal of base electrode is designated as the initial parameter set of the base electrode.

3. The detecting device of claim 1, wherein the control circuit controls the detecting circuit to produce the evaluated signal of the base electrode based on one of the parameter sets in order, and the parameter set, on which the evaluated signal of the base electrode firstly conforms to a condition based, is designated as the initial parameter set of the base electrode.

4. The detecting device of claim 1, wherein the evaluated signal is produced from one of the detecting electrodes.

5. The detecting device of claim 1, wherein the evaluated signal is produced from the sum of at least two of the detecting electrodes.

6. The detecting device of claim 1, wherein the driving signal passes through a variable resistor to at least one detecting electrode, wherein the impedance of the variable resistor is changed based on the initial parameters be provided the driving signal.

7. The detecting device of claim 1, wherein the detecting circuit changes the detecting duration based on the initial parameter of the electrode receiving the driving signal.

8. The detecting device of claim 1, wherein the driving signal is provided to at least one detecting electrode after amplified by an amplifier, wherein the amplification factor of the amplifier is changed by the detecting circuit based on the initial parameters of the electrodes be provided the driving signal.

9. The detecting device of claim 1, wherein the signal of at least one of the detecting electrodes in detecting circuit is measured after one delay phase difference. The detecting circuit changes delay phase difference by the initial parameter of electrode receiving driving signal.

10. A detecting method for touch screen, comprising:

providing a touch screen, wherein the touch screen includes a plurality of parallel driving electrodes and a plurality of parallel detecting electrodes, and the driving electrodes and the detecting electrodes cross each other at intersections;

selecting one driving electrode or one set of electrodes as the base electrode, and other electrodes or other sets of electrodes are as non-base electrode;

providing a driving signal to the base electrode, and measuring the signals of at least one detecting electrode based on the one of the parameter sets;

measuring signals of at least one detecting electrode in order based on one of other parameter sets until a signal of at least one detecting electrode is within the preset signal range when the signal of at least one detecting electrode are without a preset signal range;

designating the signal of at least one detecting electrode which is within the preset signal range as a level signal, and the parameter set on which the base electrode is based is as an initial parameter set when the driving signal is provided to the base electrode;

providing the driving signal to each one of each set of non-base electrodes in order;

measuring signals of at least one detecting electrode in order based on one of the parameter sets when the driving signal is provided to each one or each set of non-base electrodes; and

determining the initial parameter set of each one or each set of non-base electrodes, wherein the driving signal is provided separately to each one or each set of non-base electrodes, and the signal of at least one detecting electrode detected based on the initial parameter set is the closest level signal than the signals of at least one detecting electrode detected based on other parameter sets.

11. The detecting method of claim 10, wherein the driving signal passes through a variable resistor to at least one detecting electrode, wherein the impedance of the variable resistor is changed based on the initial parameters be provided the driving signal

12. The detecting method of claim 10, wherein the detecting duration is changed based on the initial parameter of the electrode receiving the driving signal.

13. The detecting method of claim 10, wherein the driving signal is provided to at least one detecting electrode after amplified by an amplifier, wherein the amplification factor of the amplifier is changed by the detecting circuit based on the initial parameters of the electrodes be provided the driving signal.

14. The detecting method of claim 10, wherein the signal of at least one of the detecting electrodes in detecting circuit is measured after one delay phase difference. The detecting circuit changes delay phase difference by the initial parameter of electrode receiving driving signal.