CN101776977A - Touch panel with impedance compensation function - Google Patents

Abstract

The invention relates to a touch panel with impedance compensation function, which is characterized in that a scanning bus is coupled with a plurality of scanning lines and used for scanning a touch picture; the detection bus is coupled with a plurality of detection lines, the detection lines respectively cross the scanning lines, and the detection lines detect at least one touch position of the touch screen; the control unit is coupled with the scanning bus and the detecting bus to control the scanning bus and the detecting bus; the plurality of scanning compensation impedance components are respectively coupled between the scanning lines and the scanning bus; the plurality of detection compensation impedance components are respectively coupled between the detection lines and the detection bus, so that signal levels of different touch positions received by the control unit are the same. Therefore, the touch panel can detect the pressure, the usability of the touch panel is further improved, the resolution of the touch panel is increased, and the operation linearity is improved.

Description

Touch panel with impedance compensation function

technical field

The present invention relates to a touch panel, in particular to a touch panel with impedance compensation function.

Background technique

In recent years, all kinds of electronic products are constantly moving towards the direction of easy operation, small size and large screen size, especially portable electronic products have stricter requirements on volume and screen size. Therefore, many electronic products integrate the touch panel and the liquid crystal display panel, so as to omit the space required for the keyboard or the control keys, thereby expanding the configurable area of the screen.

Currently, touch panels can be roughly classified into resistive, capacitive, infrared and ultrasonic touch panels, among which resistive touch panels and capacitive touch panels are the most common products. As far as the capacitive touch panel is concerned, the multi-touch feature provides a more user-friendly operation mode, so that the capacitive touch panel is gradually favored by the market. However, the capacitive touch panel must be operated by touching the touch panel with a conductive material, so the user cannot wear gloves or operate with a non-conductive material.

As for the resistive touch panel, no matter what kind of medium the user uses to touch the touch panel, it can operate, thus improving the convenience of use of the touch panel. In addition, the required cost of the resistive touch panel is relatively low and the technology of the resistive touch panel is relatively mature, so the market share is relatively high.

Please also refer to FIG. 1 , which is a schematic structural diagram of a touch panel in the prior art. As shown in the figure, the touch panel includes a scan bus 10', a detection bus 20' and a control unit 30'. The scan bus 10' is coupled to a plurality of scan lines 11', and these scan lines 11' are used to scan a touch screen, and the detection bus 20' is coupled to a plurality of detection lines 21', and these scan lines 11' are interlaced The detection lines 21', and the scanning lines 11' and the detection lines 21' are located in different layers, and the scanning lines 11' and the detection lines 21' are used to detect at least A touch position, the control unit 30' is coupled to the scan bus 10' and the detection bus 20' to control the scan bus 10' and the detection bus 20' to know that at least one position in the touch screen is touched.

As mentioned above, whether it is a capacitive or resistive touch panel, especially in the application of a multi-touch system, the multi-touch effect is usually achieved through a grid touch panel structure, that is, The scanning lines 11' and the detecting lines 21' form a gridded touch panel structure. Since the scanning lines 11' or the detecting lines 21' have different resistance values at different touch positions on the touch panel due to different paths, this is an inherent shortcoming of the touch panel. As shown in Figure 1, point A and point B must have different equivalent resistance values due to the different lengths of the detection line 21', so even if points A and point B are touched by the same size Force, will also get different magnitudes of potential output. Taking a multi-point resistive or multi-point piezoelectric touch panel as an example, after point A and point B are subjected to equal pressures, the signal seen by the control unit 30 ′ (the voltage signal reading terminal) is A The point will get a voltage value greater than point B, that is because the impedance of point A is smaller than point B (the resistance value of point A in the X direction is smaller than point B).

Based on the above, the multi-point resistive or multi-point piezoelectric touch panel does not compensate for the difference in the resistance values of the scanning line 11' and the detection line 21' in different paths, so it will lead to Under pressure, different paths will get different voltage values, so that the control unit 30' (voltage signal reading terminal) can only simply judge whether there is a signal input on the touch panel, but it is impossible to compare which input has the greater power, so it is impossible to judge The pressure in the Z direction limits the application range of the touch panel. Another disadvantage is that the resolution of the touch panel is limited to the resolution of the scan line 11' and the detection line 21' matrix itself, the actual center of gravity of the touch cannot be obtained through interpolation, and the touch linearity poor.

Contents of the invention

One of the objectives of the present invention is to provide a touch panel with impedance compensation function, which uses a plurality of scanning compensation impedance components and a plurality of detection compensation impedance components to compensate for a plurality of scanning lines and a plurality of detection lines respectively. The impedance value makes a control unit receive the same signal level at different touch positions, so that the touch panel can detect the pressure, thereby increasing the usability of the touch panel.

One of the objectives of the present invention is to provide a touch panel with impedance compensation function, which uses a plurality of scanning compensation impedance components and a plurality of detection compensation impedance components to compensate for a plurality of scanning lines and a plurality of detection lines respectively. Impedance compensation, and according to the different impedance values of scanning lines and detection lines in different paths, impedance compensation is made, so that the signal levels of different touch positions received by the control unit are the same, so as to increase the resolution of the touch panel. And improve the linearity of operation.

In order to achieve the above object, the present invention provides a touch panel with impedance compensation function, which includes:

A scan bus, coupled to a plurality of scan lines, for scanning a touch screen;

A detection bus, coupled to a plurality of detection lines, the detection lines respectively intersect the scan lines, and the detection lines detect at least one touch position of the touch screen;

a control unit, coupled to the scan bus and the detection bus, to control the scan bus and the detection bus;

a plurality of scan compensation impedance components, respectively coupled between the scan lines and the scan bus; and

A plurality of detection compensation impedance components are respectively coupled between the detection lines and the detection bus.

In the present invention, the impedance values of the scanning compensation impedance components are all greater than 1000 ohms.

In the present invention, the impedance values of the detection and compensation impedance components are all greater than 1000 ohms.

In the present invention, the impedance values of the scan compensating impedance components of the scan bus are arranged in descending/increasing order from large to small or from small to large according to the scanning start position of the touch screen.

In the present invention, the scan compensation impedance components between the scan buses and the scan lines further add a scan compensation impedance greater than 1000 ohms.

In the present invention, the impedance values of the detection compensating impedance components of the detection bus are arranged in descending/increasing order from large to small or from small to large according to the detection start position of the touch screen.

In the present invention, the detection compensation impedance components between the detection bus lines and the detection lines are respectively added with a scanning compensation impedance greater than 1000 ohms.

In the present invention, the scanning compensation impedance components and the detection compensation impedance components are respectively located in the scanning bus and the detection bus.

In the present invention, the scanning compensation impedance components and the detection compensation impedance components are a resistive material, a field effect transistor, a bicarrier junction transistor or a resistor; the scanning lines and the detection The measuring line is a conductive film or a conductive material, and the conductive film is a transparent conductive oxide film.

The present invention also discloses a touch panel with impedance compensation function, which includes:

A scan bus, coupled to a plurality of scan lines, for scanning a touch screen;

A detection bus, coupled to a plurality of detection lines, the detection lines respectively intersect the scan lines, and the scan lines detect at least one touch position of the touch screen;

a control unit, coupled to the scan bus and the detection bus, to control the scan bus and the detection bus; and

A plurality of compensating components are respectively coupled between the scan lines and the scan bus, or respectively coupled between the detection lines and the detection bus.

In the present invention, the impedance values of the compensating impedance components are greater than 1000 ohms.

In the present invention, the compensating impedance components are located in the scan bus or the detection bus.

In the present invention, the compensating impedance components are a resistive material, a field effect transistor, a bicarrier junction transistor or a resistor; the scanning lines and the detecting lines are a conductive film or a Conductive material, the conductive film is a transparent conductive oxide film.

The beneficial effect of the present invention: the touch panel with impedance compensation function provided by the present invention enables the touch panel to detect the pressure, thereby increasing the usability of the touch panel, increasing the resolution of the touch panel, and improving the Operating linearity.

Description of drawings

FIG. 1 is a schematic structural diagram of a touch panel in the prior art;

2 is a schematic structural view of a touch panel according to a preferred embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention;

4 is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention;

6 is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention;

FIG. 7 is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention; and

FIG. 8 is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention.

[Simple description of figure numbers]

current technology:

10' scan bus 11' scan line

20' detection bus 21' detection line

30' control unit

this invention:

10 scan bus 12 scan lines

20 detection bus 22 detection lines

30 control unit 40 scanning compensation impedance components

42 Detection Compensation Impedance Component 44 First Compensation Impedance Component

46 second compensation impedance component 50 touch screen

52 Touch position 60 Compensation impedance component

Detailed ways

In order to have a further understanding and understanding of the structural features of the present invention and the achieved effects, the preferred embodiments and accompanying drawings are used for a detailed description, as follows:

Please refer to FIG. 2 , which is a schematic structural diagram of a touch panel according to a preferred embodiment of the present invention. As shown in the figure, the touch panel with impedance compensation function of the present invention includes a scan bus 10 , a detection bus 20 , a control unit 30 , a plurality of scan compensation impedance components 40 and a plurality of detection compensation impedance components 42 . The scan bus 10 is coupled to a plurality of scan lines 12 for scanning a touch screen 50. The detection bus 20 is coupled to a plurality of detection lines 22, and the detection lines 22 are respectively intersected with the scan lines 12. The measuring line 22 detects at least one touch position 52 of the touch screen 50, wherein the scanning lines 12 and the detecting lines 22 are located in different layers, and the scanning lines 12 and the detecting lines 22 A spacer or a non-conductive object such as glass or film is used as a space between the two (not shown in the figure) to form the touch screen 50 . The above-mentioned technologies are well-known to those skilled in the art, so no further praise will be given here. Furthermore, the scanning lines 12 and the detecting lines 22 are a conductive film, and a preferred embodiment of the conductive film is a transparent conductive oxide (TCO) film or a conductive material. The present invention utilizes the grid touch panel structure to achieve multi-touch effects, which is only a preferred embodiment of the present invention, and the present invention is not limited to this touch panel structure. Any touch panel formed by using a conductive film falls within the protection scope of the present invention.

The control unit 30 is coupled to the scan bus 10 and the detection bus 20 to control the scan bus 10 and the detection bus 20, that is, the control unit 30 controls the scan bus 10 to drive the scan lines 12 to scan the touch screen 50, and controls the detection The detection bus 20 drives these detection lines 22 to detect the touch screen 50, so the control unit 30 can scan the touch screen 20 and these detection lines 22 to detect the touch screen 50 according to the scan lines 12, and obtain The touch position 52 is known. In addition, the scanning bus 10 is equivalent to a voltage/current signal input terminal, and the detection bus 20 is equivalent to a voltage/current signal reading terminal, so that the control unit 30 can input the voltage/current signal to the trigger through the scanning bus 10. Control the screen 50 , and then read the voltage/current signal corresponding to the scan bus 10 through the detection bus 20 to obtain at least one touch position 52 .

The scanning compensation impedance components 40 are respectively coupled between the scanning lines 12 and the scanning bus 10, and the detection compensation impedance components 42 are respectively coupled between the detection lines 22 and the detection bus 20, The control unit 30 receives the same signal level at different touch positions 52, wherein, since the scanning lines 12 and the detecting lines 22 are transparent conductive oxide films, the transparent conductive oxide films will be different due to different have different impedance values, so the present invention makes the touch position 52 When located at different positions on the scanning line 12 or the detection line 22, the impedance values obtained on the detection bus 20 (voltage/current signal reading end) will be almost the same, so that the control unit 30 receives the signal through the detection bus 20 The levels of the received signals are all the same, that is, the levels of the voltage signals or current signals received by the control unit 30 are all the same. In this way, the touch panel can detect the pressure, thereby increasing the usability of the touch panel. Wherein, the impedance values of the scanning compensation impedance components 40 and the detection compensation impedance components 42 are greater than 1000 ohms (1kΩ). When the impedance values of the scanning compensation impedance components 40 and the detection compensation impedance components 42 are larger, the The impedance values of different touch positions 52 in the scan line 12 or the detection line 22 are closer.

In addition, the scanning compensation impedance components 40 and the detection compensation impedance components 42 are a resistive material or a field effect transistor (Field Effect Transistor, FET) or a bipolar junction transistor (Bipolar Junction Transistor, BJT) .

Please also refer to FIG. 3 , which is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention. As shown in the figure, the difference between this embodiment and the embodiment of FIG. 2 is that the scanning compensation impedance components 40 and the detection compensation impedance components 42 of this embodiment are respectively arranged on the scanning bus 10 and the detection bus. 20, that is, the scanning compensation impedance components 40 are located in the scanning bus 10, and the scanning compensation impedance components 40 are respectively coupled to the scanning lines 12 to compensate the impedance values of the scanning lines 12; similarly, the The detection compensation impedance components 42 are located in the detection bus 20 , and the detection compensation impedance components 40 are respectively coupled to the detection lines 22 to compensate the impedance value of the detection lines 22 . Other technical features have been described in the previous embodiment, and will not be further praised here.

Please refer to FIG. 4 , which is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention. As shown in the figure, the difference between this embodiment and the above-mentioned embodiments is that the scanning compensation impedance components 40 and the detection compensation impedance components 42 of this embodiment are based on the distance between the scanning lines 12 and the scanning bus 10 The distance between the detection lines 22 and the detection bus 20 is used to control the impedance value of the scanning compensation impedance components 40 and the detection compensation impedance components 42, as shown in FIG. 4 , if The upper left of the touch screen 50 is used as the scanning/detection starting point as an example, the impedance values of the scanning compensation impedance components 40 on the scanning lines 12 decrease from left to right, and the detection lines 22 The impedance values of the detection compensation impedance components 42 on the scan line 12 decrease from top to bottom, that is, the impedance values of the scanning compensation impedance components 40 on the scan line 12 gradually decrease from 8R to R from left to right, and the The impedance value of the detection compensating impedance components 40 on the detection lines 22 gradually decreases from 8R to R from top to bottom. In this way, different touch positions 52 on the touch screen 50 can have different impedance compensations according to the distance between the scan bus 10 and the detection bus 20, that is, when there are points A and B on the touch screen 50 point and C point three touch positions, since the touch position of point A is relatively close to the initial scanning/detection position of the scan bus 10 and the detection bus 20, so the touch position of point A is located on the scan line 12 Both the detection line 22 and the detection line 22 are relatively short, and the compensation impedance value of the scanning compensation impedance component 40 and the detection compensation impedance component 42 corresponding to the scanning line 12 of point A and the detection line 22 is relatively large. Similarly, point C The touch position of point C is relatively far away from the initial scanning/detection position of the scan bus 10 and the detection bus 20, so the scan line 12 and the detection line 22 where the touch position of point C is located are both relatively long, and corresponding to point C The impedance value of the compensation of the scanning compensation impedance component 40 and the detection compensation impedance component 42 of the scanning line 12 and the detection line 22 is also relatively small, and the compensation of the scanning compensation impedance component 40 and the detection compensation impedance component 42 of point B is The impedance value is between point A and point C. In this way, this embodiment can more accurately have different impedance values according to the scanning lines and detection lines of different paths, so that the control unit 30 receives different touch positions. The signal levels of both are the same to increase the resolution of the touch panel and improve the linearity of operation. Moreover, since the control unit 30 receives signals at different touch positions 52 at the same level, the touch panel can detect the magnitude of the pressure, thereby increasing the usability of the touch panel.

In addition, if the setting positions of the scan bus 10 or the detection bus 20 are changed, the impedance values of the scan compensation impedance components 40 and the detection compensation impedance components 42 will vary with the distance from the scan bus 10 or the detection bus 20 The distance is adjusted, that is, when the scan bus 10 is set under the touch screen 50 (not shown in the figure), and the detection bus 20 is set on the right side of the touch screen 50, that is, the right side of the touch screen 50 When the bottom is used as the scanning/detection starting point, the impedance values of the scanning compensation impedance components 40 of the scanning bus 10 decrease from right to left; the impedance values of the detection compensation impedance components 42 of the detection bus 20 are determined by Decrease from bottom to top.

Please also refer to FIG. 5 , which is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention. As shown in the figure, the difference between this embodiment and the embodiment of FIG. 4 lies in that the scanning compensation impedance components 40 and the detection compensation impedance components 42 of this embodiment are respectively arranged on the scanning bus 10 and the detection bus. 20, that is, the scanning compensation impedance components 40 are located in the scanning bus 10, and the scanning compensation impedance components 40 are respectively coupled to the scanning lines 12 to compensate the impedance values of the scanning lines 12; similarly, the The detection compensation impedance components 42 are located in the detection bus 20 , and the detection compensation impedance components 42 are respectively coupled to the detection lines 22 to compensate the impedance value of the detection lines 22 . Other technical features have already been described in the embodiment of FIG. 4 , so no more praises will be given here.

In addition, please refer to FIG. 6 , which is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention. As shown in the figure, the difference between this embodiment and the above-mentioned embodiments is that the scanning compensation impedance components 40 between the scanning buses 10 and the scanning lines 12 in this embodiment are more than 1000 Ohm (1kΩ) scanning compensation impedance, that is, these scanning compensation impedance components 40 are further coupled to a plurality of first compensation impedance components 44, and the impedance value of these first compensation impedance components 44 is greater than 1000 ohms (1kΩ); similarly , the detection compensation impedance components 42 between the detection bus lines 20 and the detection lines 22 are further added with a scanning compensation impedance greater than 1000 ohms (1kΩ), that is, the detection compensation impedance components 42 Furthermore, a plurality of second compensating impedance components 46 are respectively coupled, and the impedance values of the first compensating impedance components 46 are greater than 1000 ohms (1 kΩ). In this way, the performance of the touch panel can be increased. Furthermore, other technical features have been described in the above-mentioned embodiments, so they will not be further praised here.

Please refer to FIG. 7 , which is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention. As shown in the figure, the difference between this embodiment and the above-mentioned embodiments is that the touch panel of this embodiment has a plurality of compensating impedance components 60, and these compensating impedance components 60 can be respectively coupled to the scanning lines 12 and The scan bus lines 10 are coupled between the detection lines 22 and the detection bus lines 20 respectively. In this embodiment, the compensating impedance components 60 are arranged between the scan bus 10 and the scan lines 12. When there are two touch positions of point D and point E on the touch screen 50, the touch position of point D is The impedance value of the touch point E is 2R+X, and the impedance value of the E point touch position is 3R+2X. Therefore, the impedance value difference between the D point touch position and the E point touch position is R+X. Therefore, these compensation impedance components 60 can perform compensation for the touch position of point D, that is, compensate the impedance value of R+X at the touch position of point D. In this way, the complex compensation impedance component 60 of this embodiment only needs to be arranged between the scanning lines 12 and the scanning bus 10, or between the detection lines 22 and the detection bus 20. In this way, as long as the scanning screen 50 The impedance value after compensation by the compensating impedance components 60 is the same as the impedance value of the farthest touch point E at the start of scanning.

Please also refer to FIG. 8 , which is a schematic structural diagram of a touch panel according to another preferred embodiment of the present invention. As shown in the figure, the difference between this embodiment and the embodiment of FIG. 7 is that the compensating impedance components 60 of this embodiment are arranged between the scan bus 10 and the scan lines 12 and between the detection bus 20 and the scan lines 12. Between the detection lines 22, taking FIG. 7 as an example, the impedance difference between the D point touch position and the E point touch position is R+X, and the compensation impedance components located on the scan bus 10 in this embodiment 60 and the impedance values of the compensating impedance components 60 on the detection bus 20 can be added to form R+X. In addition, a compensating impedance component 60 with a larger impedance value can also be used to make the impedance values of the touch point D and the touch point E the same.

To sum up, in the touch panel with impedance compensation function of the present invention, a scan bus is coupled to a plurality of scan lines for scanning a touch screen; a detection bus is coupled to a plurality of detection lines, and the detection lines The detection lines respectively intersect the scanning lines, and the detection lines detect at least one touch position of the touch screen; the control unit is coupled to the scanning bus and the detection bus to control the scanning bus and the detection bus; the scanning compensation The impedance components are respectively coupled between the scan lines and the scan bus; the detection compensation impedance components are respectively coupled between the detection lines and the detection bus. In this way, the touch panel can detect the pressure, thereby increasing the usability of the touch panel, increasing the resolution of the touch panel, and improving the linearity of operation.

In summary, it is only a preferred embodiment of the present invention, and is not intended to limit the implementation scope of the present invention. All equivalent changes and Modifications should be included within the scope of the claims of the present invention.

Claims (13)

1. the contact panel of a tool impedance compensation function, it comprises:

Scan bus couples a plurality of sweep traces, in order to scan a touch-control picture;

One detection bus couples a plurality of detection lines, staggered respectively those sweep traces of those detection lines, and those detection lines are detected at least one position of touch of this touch-control picture;

One control module couples this scanning bus and this detection bus, to control this scanning bus and this detection bus;

A plurality of scan compensation impedance components couple respectively between those sweep traces and this scanning bus; And

A plurality of detecting compensating impedance assemblies couple respectively between those detection lines and this detection bus.

2. contact panel as claimed in claim 1, wherein the resistance value of those scan compensation impedance components is all greater than 1000 ohm.

3. contact panel as claimed in claim 1, wherein the resistance value of those detecting compensating impedance assemblies is all greater than 1000 ohm.

4. contact panel as claimed in claim 1, wherein the resistance value of those scan compensation impedance components of this scanning bus is to do from large to small or by little permutation and combination to big successively decreasing/increase progressively by the scanning starting position of this touch-control picture.

5. contact panel as claimed in claim 4, wherein those scan compensation impedance components between those scanning buses and those sweep traces add the scan compensation impedance greater than 1000 ohm more respectively.

6. contact panel as claimed in claim 1, wherein the resistance value of those detecting compensating impedance assemblies of this detection bus is to do from large to small or by little permutation and combination to big successively decreasing/increase progressively by the detecting reference position of this touch-control picture.

7. contact panel as claimed in claim 6, wherein the detecting of those between those detection bus and those detection lines compensating impedance assembly adds the scan compensation impedance greater than 1000 ohm more respectively.

8. contact panel as claimed in claim 1, wherein those scan compensation impedance components and those detecting compensating impedance assemblies lay respectively in this scanning bus and this detection bus.

9. contact panel as claimed in claim 1, wherein those scan compensation impedance components and those detecting compensating impedance assembly is one to have ohmic material, a field-effect transistor, a two-carrier junction transistor or a resistance; Those sweep traces and those detection lines are a conductive film or a conductive material, and this conductive film is a transparent conductive oxide film.

10. the contact panel of a tool impedance compensation function, it comprises:

Scan bus couples a plurality of scanning linears, in order to scan a touch-control picture;

One detection bus couples a plurality of detection lines, staggered respectively those sweep traces of those detection lines, and those scanning linears are detected at least one position of touch of this touch-control picture;

One control module couples this scanning bus and this detection bus, to control this scanning bus and this detection bus; And

Anti-assembly is organized in a plurality of compensation, couples respectively between those sweep traces and this scanning bus, or couples respectively between those detection lines and this detection bus.

11. contact panel as claimed in claim 11, wherein the resistance value of those compensating impedance assemblies is all greater than 1000 ohm.

12. contact panel as claimed in claim 11, wherein those compensating impedance assemblies are to be positioned at this scanning bus or this detection bus.

13. contact panel as claimed in claim 11, wherein those compensating impedance assemblies are one to have ohmic material, a field-effect transistor, a two-carrier junction transistor or a resistance; Those sweep traces and those detection lines are a conductive film or a conductive material, and this conductive film is a transparent conductive oxide film.

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