Touch display panel and associated method

• US 8,654,265 B2
• Filed: 11/19/2010
• Issued: 02/18/2014
• Est. Priority Date: 01/29/2010
• Status: Active Grant

• Current Assignee: Ili Technology Corp. (MediaTek, Inc.)
• Original Assignee: MStar Semiconductor Incorporated (MediaTek, Inc.)
• Inventors: Hung, Guo-Kiang, Ho, Kai-Ting
• Primary Examiner(s): Glick, Edward
• Assistant Examiner(s): CHUNG, DAVID Y
• Application Number:
  US12/950,008
• Publication Number:
  US 20110187672A1
• Time in Patent Office: 1,187 Days
• Field of Search: 349/12, 345/173, 345/174
• US Class Current: 349/12
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• 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 conductive layer of a touch sensor and a pixel electrode conductive layer of a display panel are integrated to a touch display panel during the same fabrication. The touch sensor defines a plurality of sensor groups that are insulated from each other in a same conductive layer, and each of the sense groups is divided into a plurality of mutually-coupled first electrodes, a plurality of mutually-coupled second electrodes and a plurality of mutually-coupled third electrodes. The first electrodes and the third electrodes are insulated from each other and are horizontally interlaced. The first electrodes and the second electrodes are insulated from each other and are located on opposite sides of a horizontal symmetry axis. A gain for compensating a vertical coordinate of a touch position is introduced according to capacitance variances of the first electrodes and the second electrodes.

Claims

1. A touch display panel, comprising:

a first polarizer, for passing light in a first polarization direction;

a second polarizer, for passing light in a second polarization direction;

a first conductive layer, disposed between the first polarizer and the second polarizer, the first conductive layer comprising a plurality of electrodes that are insulated from one another, wherein the plurality of electrodes comprises a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes, and the first electrodes, the second electrodes, and the third electrodes are insulated from each other, the first electrodes and the second electrodes are interlaced in a first direction, at least two of the first electrodes are coupled to each other to form a sensing group, and at least two of the third electrodes are coupled to each other to form another sensing group;

a display unit structure, disposed between the first conductive layer and the second polarizer, the display unit structure comprising a plurality of display units; and

a second conductive layer, disposed between the display unit structure and the second polarizer, the second conductive layer comprising a plurality of pixel electrodes.

2. The touch display panel as claimed in claim 1, further comprising:

a color filter, defined between the first polarizer and the second conductive layer, for displaying a plurality of colors on the display units of the touch display panel.

3. The touch display panel as claimed in claim 1, wherein a cross section size of each of the first electrodes in the first direction changes along a second direction, and a cross section size of each of the second electrodes in the first direction changes along the second direction inversely relative to the first electrode, wherein the second direction is perpendicular to the first direction.

4. The touch display panel as claimed in claim 1, wherein the first conductive layer transmits a common voltage, the first conductive layer comprising a plurality of insulation gaps that divide the first conductive layer into the electrodes.

5. The touch display panel as claimed in claim 1, further comprising a third conductive layer, defined between the first conductive layer and the second conductive layer, for transmitting a common voltage.

6. The touch display panel as claimed in claim 5, further comprising a fourth conductive layer, disposed between the first conductive layer and the first polarizer, the fourth conductive layer comprising a plurality of electrodes that are insulated from one another, the electrodes transmitting an electrical signal in response to a touch on the touch display panel.

7. The touch display panel as claimed in claim 5, wherein the third conductive layer comprises a plurality of insulation gaps that divide the third conductive layer into a plurality of electrodes.

8. The touch display panel as claimed in claim 7, wherein a pattern of the electrodes of the first conductive layer is overlapped with a pattern of the electrodes of the third conductive layer.

9. The touch display panel as claimed in claim 1, further comprising:

a glass substrate, defined between the second conductive layer and the second polarizer.

10. The touch display panel as claimed in claim 1, further comprising:

a glass substrate, defined between the first polarizer and the first conductive layer.

11. A method of manufacturing a touch display panel, comprising:

forming a first conductive layer on a first glass substrate, the first conductive layer comprising a plurality of electrodes that are insulated from one another, and the electrodes of the first conductive layer comprising a plurality of first electrodes, a plurality of second electrodes, and a plurality of third electrodes;

forming a color filter, for filtering colors for a plurality of display units of the touch display panel;

forming a second conductive layer on a second glass substrate, the second conductive layer comprising a plurality of pixel electrodes;

insulating each of the first electrodes from each of the second electrodes;

interlacing the first electrodes and the second electrodes in a first direction;

forming a sensing group by coupling at least two of the first electrodes;

insulating the first electrodes and the second electrodes from the third electrodes; and

forming another sensing group by coupling at least two of the third electrodes.

12. The method as claimed in claim 11 further comprising:

forming the first electrodes in a way that a cross-section size of each of the first electrodes in the first direction changes along a second direction; and

forming the second electrodes in a way that a cross-section size of each of the second electrodes in the first direction changes along the second direction inversely relative to the first electrodes, the second direction being perpendicular to the first direction.

13. The method as claimed in claim 11, further comprising forming the electrodes by dividing the first conductive layer by a plurality of insulation gaps.

14. The method as claimed in claim 11, further comprising:

transmitting a common voltage from the first conductive layer; and

dividing the first conductive layer into the electrodes by a plurality of insulation gaps.

15. The method as claimed in claim 11, further comprising forming a third conductive layer for transmitting a common voltage via the conductive fabrication.

16. The method as claimed in claim 15, further comprising dividing the third conductive layer into a plurality of electrodes via a plurality of insulation gaps.

17. The method as claimed in claim 11, further comprising:

gluing a first polarizer and a second polarizer to the first glass substrate and the second glass substrate, respectively.

18. A method for reducing errors due to an insulation gap in a touch sensor, said method comprising the steps of:

sensing a capacitance variance of each of a first set of electrodes to obtain a first variance;

sensing a capacitance variance of each of a second set of electrodes to obtain a second variance;

sensing a capacitance variance of each of a third set of electrodes to obtain a third variance;

obtaining a gain value according to a difference between said first variance and said second variance;

determining a y coordinate offset according to said capacitance variances of each of the first, second, and third sets of electrodes;

compensating said y coordinate offset according to said gain value to obtain a compensated y coordinate offset.