Touch sensing method for resistive type touch apparatus

• US 8,405,525 B2
• Filed: 06/17/2010
• Issued: 03/26/2013
• Est. Priority Date: 06/18/2009
• Status: Expired due to Fees

• Current Assignee: Dongguan Masstop Liquid Crystal Display Company Limited (Wintek Corporation), Wintek Corporation
• Original Assignee: Dongguan Masstop Liquid Crystal Display Company Limited (Wintek Corporation), Wintek Corporation
• Inventors: Wang, Wen-Chun, Su, Kuo-Chang, Lai, Chih-Chang
• Primary Examiner(s): Jean Pierre, Peguy
• Application Number:
  US12/818,125
• Publication Number:
  US 20100321214A1
• Time in Patent Office: 1,013 Days
• Field of Search: 341/22, 341/32, 341/28, 341/34, 341/20, 345/173, 340/407
• US Class Current: 341/20
• CPC Class Codes: G06F 2203/04808 Several contacts: gestures triggering a specific function, e.g. scrolling, zooming, right-click, when the user establishes several contacts with the surface simultaneously; e.g. using several fingers or a combination of fingers and pen
• 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 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A touch sensing method for a resistive type touch apparatus includes a touch panel and a driving circuit. In the touch sensing method, a single-touch mode or a multi-touch mode can be selected. In addition, the touch sensing method includes an analog driving method and a digital driving method to equip the resistive type touch apparatus with at least two sorts of resolutions.

Claims

1. A touch sensing method, adapted to a resistive type touch apparatus, wherein the resistive type touch apparatus comprises:

a touch panel comprising;

a first transparent substrate;

a plurality of first conductive patterns disposed on the first transparent substrate, each of the first conductive patterns being parallel to a first direction;

a plurality of first electrodes and a plurality of second electrodes respectively disposed on two ends of the first conductive patterns;

a second transparent substrate disposed opposite to the first transparent substrate;

a plurality of second conductive patterns disposed on the second transparent substrate, the first conductive patterns and the second conductive patterns being located between the first transparent substrate and the second transparent substrate, each of the second conductive patterns being parallel to a second direction, wherein the first direction intersects the second direction;

a plurality of third electrodes and a plurality of fourth electrodes respectively disposed on two ends of the second conductive patterns;

a plurality of spacers located between the first transparent substrate and the second transparent substrate; and

a driving circuit, configured to set the resistive type touch apparatus to operate in a digital mode or in an analog mode, the driving circuit being coupled to the first electrodes, the second electrodes, the third electrodes, and the fourth electrodes,

wherein overlapping portions between the first conductive patterns and the second conductive patterns are defined as a plurality of sensing blocks, and the touch sensing method further comprises;

selecting an operation mode, such that the resistive type touch apparatus operates either in a single-touch mode or in a multi-touch mode;

when the resistive type touch apparatus operates in the single-touch mode, the driving circuit activating a first analog scan and sensing function;

when the resistive type touch apparatus operates in the multi-touch mode, the driving circuit activating either a second analog scan and sensing function or a digital scan and sensing function; and

when the digital scan and sensing function is activated and the driving circuit senses that one of the sensing blocks is touched, the driving circuit then activating the first analog scan and sensing function.

2. The touch sensing method of claim 1, when the driving circuit activates the first analog scan and sensing function, the touch sensing method further comprising:

simultaneously inputting a first voltage to the first electrodes and a second voltage to the second electrodes by applying the driving circuit;

sensing a first voltage division signal and sending back the first voltage division signal to the driving circuit by applying the third electrodes, such that a coordinate X in the first direction is defined;

simultaneously inputting a third voltage to the third electrodes and a fourth voltage to the fourth electrodes by applying the driving circuit;

sensing a second voltage division signal and sending back the second voltage division signal to the driving circuit by applying the first electrodes, such that a coordinate Y in the second direction is defined; and

combining the coordinate X in the first direction and the coordinate Y in the second direction, such that a touch position (X, Y) is determined.

3. The touch sensing method of claim 2, further comprising:

electrically connecting the first electrodes with one another so as to receive the first voltage, and electrically connecting the second electrodes with one another so as to receive the second voltage; and

electrically connecting the third electrodes with one another so as to receive the third voltage, and electrically connecting the fourth electrodes with one another so as to receive the fourth voltage.

4. The touch sensing method of claim 1, when the driving circuit activates the second analog scan and sensing function, the touch sensing method further comprising:

sequentially inputting different voltages to the two ends of the first conductive patterns via the first electrodes and the second electrodes by applying the driving circuit;

sensing at least a first sensing signal and sending back the at least a first sensing signal to the driving circuit by applying the third electrodes, such that at least a coordinate X in the first direction is determined;

sequentially inputting different voltages to the two ends of the second conductive patterns via the third electrodes and the fourth electrodes by applying the third electrodes;

sensing at least a second sensing signal and sending back the at least a second sensing signal to the driving circuit by applying the first electrodes, such that at least a coordinate Y in the first direction is determined; and

combining the at least a coordinate X in the first direction and the at least a coordinate Y in the second direction, such that at least a touch position (X, Y) is determined.

5. The touch sensing method of claim 4, wherein the driving circuit comprises at least an analog-to-digital converter (ADC), and the touch sensing method further comprises:

converting the at least a first sensing signal and the at least a second sensing signal into a first digital signal and a second digital signal by applying the ADC; and

determining the at least a coordinate X in the first direction according to the first digital signal and the at least a coordinate Y in the second direction according to the second digital signal,

wherein when the first digital signal and the second digital signal are between 2 bits and 4 bits, the resistive type touch apparatus is defined as operating in a low resolution analog mode; and

when the first digital signal and the second digital signal are equal to or more than 5 bits, the resistive type touch apparatus is defined as operating in a high resolution analog mode.

6. The touch sensing method of claim 5, wherein the driving circuit comprises at least a first ADC and a second ADC, and the touch sensing method further comprises:

first, operating the resistive type touch apparatus in the low resolution analog mode;

respectively converting the at least a first sensing signal and the at least a second sensing signal into the first digital signal and the second digital signal by applying the second ADC, wherein the first digital signal and the second digital signal are between 2 bits and 4 bits;

then, operating the resistive type touch apparatus in the high resolution analog mode;

respectively converting the at least a first sensing signal and the at least a second sensing signal into a third digital signal and a fourth digital signal by applying the first ADC, wherein the third digital signal and the fourth digital signal are equal to or more than 5 bits; and

determining the at least a coordinate X in the first direction according to the third digital signal and the at least a coordinate Y in the second direction according to the fourth digital signal.

7. The touch sensing method of claim 1, when the driving circuit activates the digital scan and sensing function, the touch sensing method further comprising:

inputting a plurality of fifth voltages to the first electrodes of the first conductive patterns by applying the driving circuit so as to scan;

sensing at least a third sensing signal and sending back the at least a third sensing signal to the driving circuit by applying the third electrodes of the second conductive patterns, such that at least one of the sensing blocks touched by a user is determined.

8. The touch sensing method of claim 7, further comprising:

sensing that at least two of the sensing blocks are touched and outputting a plurality of 1-bit signals corresponding to the touched sensing blocks by applying the driving circuit.

9. The touch sensing method of claim 7, further comprising:

sensing that at least two of the sensing blocks are touched and activating a third analog scan and sensing function by applying the driving circuit;

respectively inputting different voltages to the two ends of the first conductive patterns corresponding to the touched sensing blocks;

one end of each of the second conductive patterns corresponding to the touched sensing blocks sensing at least two fourth sensing signals and sending back the at least two fourth sensing signals to the driving circuit, such that a plurality of first coordinates in the first direction are determined;

respectively inputting different voltages to the two ends of the second conductive patterns corresponding to the touched sensing blocks;

one end of each of the first conductive patterns corresponding to the touched sensing blocks sensing at least two fifth sensing signals and sending back the at least two fifth sensing signals to the driving circuit, such that a plurality of second coordinates in the second direction are determined; and

combining the first coordinates in the first direction and the second coordinates in the second direction, such that a plurality of touch positions (X, Y) are determined.

10. The touch sensing method of claim 9, wherein the driving circuit comprises at least an ADC, and the touch sensing method further comprises:

converting the at least two fourth sensing signals and the at least two fifth sensing signals into a plurality of fifth digital signals and a plurality of sixth digital signals by applying the at least an ADC, such that the first coordinates in the first direction and the second coordinates in the second direction are determined,

wherein when the fifth digital signals and the sixth digital signals are between 2 bits and 4 bits, the resistive type touch apparatus is defined as operating in a low resolution analog mode; and

when the fifth digital signals and the sixth digital signals are equal to or more than 5 bits, the resistive type touch apparatus is defined as operating in a high resolution analog mode.

11. The touch sensing method of claim 10, wherein the driving circuit comprises at least a third ADC and a fourth ADC, and the touch sensing method further comprises:

respectively converting the at least two fourth sensing signals and the at least two fifth sensing signals into the fifth digital signals and the sixth digital signals by applying the fourth ADC, wherein the fifth digital signals and the sixth digital signals are between 2 bits and 4 bits;

then, respectively converting the at least two fourth sensing signals and the at least two fifth sensing signals into a plurality of seventh digital signals and a plurality of eighth digital signals by applying the third ADC, wherein the seventh digital signals and the eighth digital signals are equal to or more than 5-bits; and

determining the first coordinates in the first direction according to the seventh digital signals and the second coordinates in the second direction according to the eighth digital signals.

12. The touch sensing method of claim 1, wherein the driving circuit comprises at least a switch circuit, and the touch sensing method further comprises:

determining whether the resistive type touch apparatus operates in the digital mode or the analog mode according to a control signal by applying the at least a switch circuit.

13. The touch sensing method of claim 1, wherein the driving circuit comprises at least a first ADC and a second ADC, and the touch sensing method further comprises:

determining whether the resistive type touch apparatus operates in a low resolution analog mode or in a high resolution analog mode,

wherein when the resistive type touch apparatus operates in the high resolution analog mode, the driving circuit outputs a signal equal to or more than 5 bits via the at last a first ADC; and

when the resistive type touch apparatus operates in the low resolution analog mode, the driving circuit outputs a signal between 2 bits and 4 bits via the second ADC.