TOUCH PANEL, POSITION SENSING METHOD OF TOUCH PANEL, AND INTEGRATED CIRCUIT

• US 20150177901A1
• Filed: 06/29/2012
• Published: 06/25/2015
• Est. Priority Date: 06/25/2012
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Hashimoto, Masashi
• Granted Patent: US 9,639,201 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04112 Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material
• CPC Class Codes: G06F 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry
• 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 3/0445 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 touch panel according to the disclosure includes a touch screen including a plurality of X electrode lines and Y electrode lines, which are alternately disposed with each other, and generating signals that vary depending on a touch position; and a plurality of comparators connected between first and second Y electrode lines adjacent to each other, wherein the touch position on the touch screen is detected based on output codes prepared by using output values of the comparators. A method for detecting a position of a touch panel according to the disclosure includes the steps of generating a position signal that varies according to a touch position between a plurality of X electrode lines and first and second Y electrode lines, which are adjacent to each other and alternately disposed with X electrode lines; detecting adjacent signals from a Y electrode line adjacent to a left of the first Y electrode and a Y electrode line adjacent to a right of the second Y electrode line; inputting the adjacent signal as an input signal of the comparator; overlapping the position signal on one of the detected adjacent signals; and comparing the input signal using the comparator. An integrated circuit according to the disclosure includes a plurality of comparators including a positive input terminal receiving a first input signal that varies depending on a touch position, a negative input terminal receiving a second input signal, and an output terminal outputting a comparison signal of the first and second input signals; and an operation unit generating a position signal by reading out the comparison signal of the comparators.

Claims

1. A touch panel comprising:

a touch screen including a plurality of X electrode lines and Y electrode lines, which are alternately disposed with each other, and generating signals that vary depending on a touch position; and

a plurality of comparators connected between first and second Y electrode lines adjacent to each other,

wherein the touch position on the touch screen is detected based on output codes prepared by using output values of the comparators.

2. The touch panel of claim 1, wherein, when a pitch between the first and second Y electrode lines adjacent to each other is set to 1/n resolution, (n−

1) comparators are disposed in parallel between the first and second Y electrode lines adjacent to each other.

3. The touch panel of claim 2, wherein, when a center of the first Y electrode line is set to 0 and a center of the second Y electrode line is set to Lp, the touch position is divided into three sections of −

Lp/4=XLp/4 (section 0), Lp/4=X3Lp/4 (section 1) and 3Lp/4=X5Lp/4 (section 2).

4. The touch panel of claim 3, wherein the touch position is detected by outputting bits that vary depending on touched sections in a state that a digital output 2 bit code of a pair of the first and second Y electrode line is set as 0₁, an output of the first comparator is set as a high-order bit and an output of the second comparator is set as a low-order bit.

5. A touch panel comprising:

first and second Y electrode lines, which are adjacent to each other and divided into at least two main sections each of which is divided into at least two sub-sections; and

a TD electrode line disposed across the first and second Y electrode lines,

wherein the touch position is detected by comparing a potential difference value at a first time point according to the touch position between the first and second Y electrode lines with a potential value applied to the TD electrode line at a second time point corresponding to a potential value at a boundary point between adjacent sub-sections.

6. The touch panel of claim 5, wherein one main section is divided into odd sub-sections.

7. The touch panel of claim 6, wherein a width of the sub-section disposed at both side ends of the sub-sections is a half of a width of the sub-section disposed at a center of the sub-sections.

8. The touch panel of claim 7, wherein a center of the sub-section located at a center of the sub-sections matches with a center of the main section including the sub-section located at the center of the sub-sections.

9. An integrated circuit comprising:

a plurality of comparators including a positive input terminal receiving a first input signal that varies depending on a touch position, a negative input terminal receiving a second input signal, and an output terminal outputting a comparison signal of the first and second input signals;

a voltage applying unit connected to the positive and negative input terminals to apply a drive voltage; and

an operation unit generating a position signal by reading out the comparison signal of the comparators.

10. The integrated circuit of claim 9, wherein a voltage difference between the positive and negative input terminals is divided into at least two main sections each of which is divided into at least two sub-sections, and a voltage applied from the voltage applying unit corresponds to a voltage at a boundary point between adjacent sub-sections.

11. The integrated circuit of claim 10, wherein the operation unit detects the touch position by comparing a potential difference value according to the touch position between the positive and negative input terminals with a potential value applied from the voltage applying unit corresponding to a potential value at the boundary point between the adjacent sub-sections.

13. The integrated circuit of claim 9, wherein the comparators include first and second comparators connected in parallel to each other.

14. The integrated circuit of claim 13, a plurality of first comparators including a positive input terminal receiving a first input signal which is related to an X-axis and varies depending on a touch position, a negative input terminal receiving a second input signal, and an output terminal outputting a comparison signal of the first and second input signals;

a plurality of second comparators having a positive input terminal receiving a first input signal which is related to a Y-axis and varies depending on a touch position, a negative input terminal receiving a second input signal, and an output terminal outputting a comparison signal of the first and second input signals.

16. The integrated circuit of claim 9, wherein the integrated circuit is independently installed in a touch panel or integrated in a form of a one chip with at least one of a chip of a personal portable terminal and a driving chip of an LCD.

22. The integrated circuit of claim 14, wherein, when the comparators parallel-connected to each other are grouped in one group, the operating part receives comparative signals of comparators belonging to an adjacent another group to generate the position signal.

23. The integrated circuit of claim 14, wherein the dividing the first and second Y electrode lines into three sections by using the first comparators connected in parallel to each other and specifying one of the three sections according to the position signal output from the first comparators.

24. The integrated circuit of claim 14, wherein the dividing the first and second Y electrode lines into three sections by using the first comparators connected in parallel to each other and specifying one of the three sections according to the position signal output from the first comparators.

12. (canceled)

15. (canceled)

17-20. -20. (canceled)

21. The integrated circuit of 14, wherein the operation unit that generates a position signal related to the X-axis by reading out the comparison signal of the first comparators and generates a position signal related to the Y-axis by reading out the comparison signal of the second comparators.