Touch sensing method for touch panel

• US 9,146,648 B2
• Filed: 06/09/2014
• Issued: 09/29/2015
• Est. Priority Date: 07/28/2011
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display Incorporated
• Inventors: Doi, Koji, Nagata, Koji
• Primary Examiner(s): Ghebretinsae, Temesgh
• Assistant Examiner(s): Ketema, Benyam
• Application Number:
  US14/299,175
• Publication Number:
  US 20140285470A1
• Time in Patent Office: 477 Days
• Field of Search: 345/174
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• 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

Abstract

A touch sensing method, for sensing a touch point on a touch panel, includes the steps of measuring capacitances of the touch panel, detecting touch points on the touch panel based on the capacitance, determining tentative coordinates of the respective detected touch points, assigning priorities for a given high coordinate precision to the respective touch points based on a state of the touch points, selecting coordinate calculation algorithms corresponding to the assigned priorities by the respective touch points, estimating a calculation time necessary for calculating the coordinates of the touch points detected, determining whether the calculation time estimated is within a specified time or not, and calculating the coordinates of the respective touch points using the selected coordinate calculation algorithms corresponding to the assigned priorities when the calculation time estimated calculation time is within the specified time.

Claims

1. A method for calculating a touch coordinate on a touch panel, wherein the touch panel has a plurality of X electrodes and a plurality of Y electrodes, the method comprising the steps of:

a measuring interelectrode capacitances between the plurality of X electrodes and the plurality of Y electrodes;

storing the measured interelectrode capacitance values between the plurality of X electrodes and the plurality of Y electrodes;

detecting touch points on the touch panel based on the stored interelectrode capacitance values;

determining tentative coordinates of the respective detected touch points;

assigning priorities for a given high coordinate precision to the respective touch points based on a state of the touch points;

selecting coordinate calculation algorithms corresponding to the assigned priorities assigned to the respective touch points;

estimating a calculation time necessary for calculating the coordinates of the touch points detected, the calculation time being estimated using the selected coordinate calculation algorithms;

determining whether the calculation time estimated is within a specified time or not;

changing coordinate calculation algorithms and estimating the calculation time again when the estimated calculation time is not within the specified time; and

calculating the coordinates of the respective touch points using the selected coordinate calculation algorithms corresponding to the priorities when the calculation time is within the specified time.

2. The method for calculating a touch coordinate on the touch panel according to claim 1, wherein the step of selecting coordinate calculation algorithms includes:

a step of referring a predetermined algorithm information list storing the plurality of coordinate calculation algorithms, required times when calculation is performed using the coordinate calculation algorithms, and obtained coordinate precisions; and

a step of selecting the coordinate calculation algorithms corresponding to the assigned priorities.

3. The method for calculating a touch coordinate on the touch panel according to claim 1, further comprising:

a step of referring a predetermined touch detection setting storing a maximum number of touch points that is an upper limit of a number of touch points for which coordinate calculation is performed and a coordinate calculation time allowed in touch detection processing when there are a plurality of touches simultaneously;

wherein detection of the touch points is discontinued in the step of detecting touch points when a total number of detected touch points exceeds the maximum number of touch points; and

wherein the coordinate calculation time stored in the touch detection setting is used as the specified time in the step of determining whether the calculation time estimated is within the specified time or not.

4. The method for calculating a touch coordinate on the touch panel according to claim 1, further comprising:

a step of referring a predetermined region setting storing a specific region on the touch panel and coordinating precision required in the specific region;

wherein a priority corresponding to the coordinate precision of the specific region is assigned as the priority assigned to a touch point in the specific region stored in the region setting in the step of assigning priorities.

5. A touch sensing method, for sensing a touch point on a touch panel, comprising the steps of:

measuring capacitances of the touch panel;

detecting touch points on the touch panel based on the capacitance;

determining tentative coordinates of the respective detected touch points;

assigning priorities for a given high coordinate precision to the respective touch points based on a state of the touch points;

selecting coordinate calculation algorithms corresponding to the assigned priorities by the respective touch points;

estimating a calculation time necessary for calculating the coordinates of the touch points detected;

determining whether the calculation time estimated is within a specified time or not; and

calculating the coordinates of the respective touch points using the selected coordinate calculation algorithms corresponding to the assigned priorities when the calculation time estimated calculation time within the specified time.

6. The touch sensing method according to claim 5, wherein

the step of selecting coordinate calculation algorithms includes a step of referring a predetermined algorithm information list storing the plurality of coordinate calculation algorithms, required times when calculation is performed using the coordinate calculation algorithms, and obtained coordinate precisions.

7. The touch sensing method according to claim 5, further comprising:

a step of referring a predetermined touch detection setting storing a maximum number of touch points that is an upper limit of a number of touch points for which coordinate calculation is performed and a coordinate calculation time allowed in touch detection processing when there are a plurality of touches simultaneously.

8. The touch sensing method according to claim 7, wherein detection of the touch points is discontinued in the step of detecting touch points when a total number of detected touch points exceeds the maximum number of touch points;

and

wherein the coordinate calculation time stored in the touch detection setting is used as the specified time in the step of determining whether the calculation time estimated is within the specified time or not.

9. The touch sensing method according to claim 5, further comprising:

a step of referring a predetermined region setting storing a specific region on the touch panel and coordinating precision required in the specific region;

wherein a priority corresponding to the coordinate precision of the specific region is assigned as the priority assigned to a touch point in the specific region stored in the region setting in the step of assigning priorities.