This application claims the priority benefit of Taiwan application serial no. 96148681, filed on Dec. 12, 2007. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
1. Field of the Invention
The present invention relates to a resistance type touch panel, and in particular, to a detecting method of multiple-point touching.
2. Description of Related Art
With rapid developments and applications of the information technology, wireless mobile telecommunication, and information appliances, the input devices of many information products are changed from a traditional keyboard, a mouse and so forth to touch panels, so as to satisfy the requirements of convenience in carrying, light weight, and user-friendly operations.
Presently, the touch panel that can be operated by human fingers is divided into two categories according to a driving method of the touch panel, i.e. a resistance panel module and a capacitor panel module. With reference to the resistance panel module, a user is required to factually exert pressure on the resistance panel module, so that a portion inside the resistance panel module is electrically connected, and accordingly a corresponding coordinate signal is generated, and thereby the resistance panel module is more likely to be malfunctioned. A detecting method of one-point touching of a conventional resistance panel module is further described below accompanied with drawings.
When detecting the coordinate in the Y direction, the side X− is switched to an open circuit state. A control signal C1 controls a switch 121 to be switched on/off, and thereby a voltage +VCC is supplied to the side Y+. Further, a control signal C2 controls a switch 122 to be switched on/off, and thereby a ground voltage GND is supplied to the side Y−. Then, a voltage difference between the side X+ and the side Y− is measured by an analog-to-digital converter 40. The voltage difference between the side X+ and the side Y− is proportional to the coordinate in the Y direction. Therefore, according to the voltage difference between the side X+ and the side Y−, the coordinate of the point P in the Y direction can be estimated. Similarly, according to the same principle, the coordinate of the point P in the X direction can be estimated, and the detailed descriptions are not repeated herein.
It should be noted that, the conventional resistance panel module can only detect the event of one-point touching. When the event of multiple-point touching occurs, the conventional resistance panel module fails to conduct detection correspondingly. Therefore, the conventional resistance panel module can not meet the demands of multiple functions.
The present invention provides a touch panel capable of detecting an event of multiple-point touching.
The present invention provides a touch panel capable of estimating the event of multiple-point touching according to a variation of the resistance value of the conducting path in the resistance panel module.
The present invention provides a touch panel including a resistance panel module, a voltage dividing resistance, a selector, and a detecting module. The resistance panel module includes a first conducting path and a second conducting path. One end of the voltage dividing resistance receives a voltage source. The selector connects the other end of the voltage dividing resistance, and connects two ends of the first conducting path and two ends of the second conducting path. The detecting module is coupled to the selector. When the event of multiple-touching occurs, the first conducting path is electrically connected to the second conducting path at multiple points, the selector selects the first conducting path to connect the voltage dividing resistance in series, and the detecting module detects the two ends of the first conducting path, so as to estimate the event of multiple-point touching.
According to one embodiment of the present invention, the selector includes a first multiplexer, a second multiplexer, and a third multiplexer. The first multiplexer includes a first input terminal, a second input terminal, and an output terminal respectively connected to the first end of the first conducting path, the first end of the second conducting path, and the voltage dividing resistance. The second multiplexer includes a first input terminal, a second input terminal, and an output terminal respectively connected to the first end of the first conducting path, the first end of the second conducting path, and the detecting module. The third multiplexer includes a first input terminal, a second input terminal, and an output terminal respectively connected to the second end of the first conducting path, the second end of the second conducting path, and the detecting module.
According to one embodiment of the present invention, the detecting module is an analog-to-digital converter having a first input terminal and a second input terminal respectively coupled to the output terminal of the second multiplexer and the output terminal of the third multiplexer.
According to one embodiment of the present invention, the detecting module detects the two ends of the first conducting path means detecting the voltage or the resistance value at the two points of the first conducting path, so as to estimate a relative distance of the event of multiple-point touching. According to another embodiment, a table is constructed based on the result of estimating the event of multiple-point touching according to the resistance value, and the relative distance corresponding to the resistance value is obtained by looking up the table. According to still another embodiment, when no matching data are found in the table, two resistance values adjacent to the resistance value are based to perform an interpolation method to obtain the corresponding relative distance. According to another embodiment of the present invention, the event of multiple-point touching is two-point touching (i.e., the touch panel is touched at two points).
According to one embodiment of the present invention, the resistance panel module includes a first conductive substrate and a second conductive substrate. The first conductive substrate has the first conducting path along a first direction. The second conductive substrate is parallel to the first conductive substrate. The second conductive substrate has the second conductive path along a second direction, wherein the first direction and the second direction are perpendicular to each other. According to another embodiment, the resistance panel module is a 4-wire type resistance panel module.
From another point of view, the present invention provides a touch panel including a resistance panel module, a first voltage dividing resistance, a second voltage dividing resistance, a selector, and a detecting module. The resistance panel module includes a first conducting path and a second conducting path. One end of the first voltage dividing resistance is coupled to the first conducting path. One end of the second voltage dividing resistance is coupled to the second conducting path. The selector receives a voltage source. The selector connects the other end of the first voltage dividing resistance and the other end of the second voltage dividing resistance, and connects two ends of the first conducting path and two ends of the second conducting path. The detecting module is coupled to the selector. When the event of multiple-point touching occurs, the first conducting path is electrically connected to the second conducting path at multiple points, the selector selects the voltage source to connect the first voltage dividing resistance in series, and the detecting module detects the two ends of the first conducting path, so as to estimate the event of multiple-point touching.
According to one embodiment of the present invention, the selector includes a first multiplexer, a second multiplexer, and a third multiplexer. The first multiplexer has a first input terminal, a second input terminal, and an output terminal respectively connected to the other end of the first voltage dividing resistance, the other end of the second voltage dividing resistance, and the voltage source. The second multiplexer includes a first input terminal, a second input terminal, and an output terminal respectively connected to the first end of the first conducting path, the first end of the second conducting path, and the detecting module. The third multiplexer includes a first input terminal, a second input terminal, and an output terminal respectively connected to the second end of the first conducting path, the second end of the second conducting path, and the detecting module.
When the event of multiple-point touching occurs, a portion of the first conducting path in the resistance panel module is connected to a portion of the second conducting path in parallel with multiple points, and thereby the resistance value of the first conducting path is reduced. According to the present invention, the variation of the resistance value/voltage of the first conducting path is measured to estimate the event of multiple-point touching. Therefore, the variation of the resistance value can serve as an input signal of an interface between humans and machines to control an electronic device.
To make the aforesaid features and advantages of the present invention more comprehensible, several embodiments accompanied with figures are described in detail below.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A conventional resistance panel module can only detect a position of touching when a panel is touched at one point. When an event of multiple-point touching occurs, the conventional resistance panel module is not responsive. Accordingly, when the event of multiple-point touching occurs, embodiments of the present invention utilize a variation of the resistance value (voltage) of the resistance panel module to estimate the event of multiple-point touching.
Referring to
In
When the event of two-point touching does not occur, the resistance value between the side Y+ and the side Y− is the sum of the resistance values of the resistances 101, 102, and 103. However, when the event of two-point touching occurs, the resistance value between the point Py1 and the point Py2 is reduced because the resistance 102 is connected in parallel to the circuit consisting of the resistance 107, the resistance 105 and the resistance 108 in series connection. As a distance between the point Py1 and the point Py2 is getting larger along a Y direction, i.e., the resistance value between the point Py1 and the point Py2 is getting larger, the reduction of the resistance value between the point Py1 and the point Py2 increases due to the parallel connection effect of the resistances. In other words, according to the deduction of the resistance value between the side Y+ and the side Y−, the distance between the point Py1 and the point Py2 along the Y direction can be estimated.
Likewise, when the event of two-point touching does not occur, the resistance value between the side X+ and the side X− is the sum of the resistance values of the resistances 104, 105, and 106. However, when the event of two-point touching occurs, the resistance value between the point Px1 and the point Px2 is reduced because the resistance 105 is connected in parallel to the circuit consisting of the resistance 107, the resistance 102 and the resistance 108. As the distance between the point Px1 and the point Px2 is getting larger along an X direction, i.e., the resistance value between the point Px1 and the point Px2 is getting larger, the reduction of the resistance value between the point Px1 and the point Px2 increases due to the parallel connection effect of the resistances. In other words, according to the deduction of the resistance value between the side X+ and the side X−, the distance between the point Px1 and the point Px2 along the X direction can be estimated.
Hereinafter, the step S401 is explained in detail. When the event of touching does not occur yet, the detecting module 50 may first detect a first resistance value between the side Y+ and the side Y−. Then, when the event of two-point touching occurs, the detecting module 50 switches the side X+ and the side X− to an open circuit state, and detects a second resistance value between the side Y+ and the side Y−. According to the difference between the first resistance value and the second resistance value, the variation of the resistance value between the side Y+ and the side Y− can be known. An implementation of measuring the variation of the resistance value between the side Y+ and the side Y− of the touch panel 60 is provided below as a reference for persons of ordinary skill in the art.
The switch 121 can be switched on/off according to a control signal C1, and thereby a voltage +VCC can be supplied to one end of the voltage dividing resistance 201 and the reference voltage terminal +REF of the analog-to-digital converter 40. The switch 122 is switched on/off according to a control signal C2, and thereby a ground voltage GND can be supplied to the input terminal −IN and the reference voltage terminal −REF of the analog-to-digital converter 40.
The selector 30 includes multiplexers 131, 132 and 133. According to the present embodiment, output terminals of the multiplexers 131, 132 and 133 are respectively coupled to the other end of the voltage dividing resistance 201, the output terminals +IN and −IN of the analog-to-digital converter 40. The multiplexers 131, 132 and 133 determine the coupling relationship between the resistance panel module 10 and the analog-to-digital converter 40 according to control signals C3˜C5. The detected data of the detecting module 50 varies according to different control signals C1˜C5. For example, when it is intended to detect the variation of the resistance value between the side Y+ and the side Y− by using the detecting module 50, the switch 121 can be switched to a conducting state according to the control signal C1. The switch 122 can be switched to the conducting state according to the control signal C2. The multiplexer 131 can be switched to 0 according to the control signal C3, so that the voltage dividing resistance 201 is coupled to the side Y+. The multiplexer 132 can be switched to 1 according to the control signal C4, so that the input terminal +IN of the analog-to-digital converter 40 is coupled to the side Y+. The multiplexer 133 can be switched to 1 according to the control signal C5, so that the input terminal −IN of the analog-to-digital converter 40 is coupled to the side Y−.
The resistance values of the voltage VCC, the ground voltage GND, and the voltage dividing voltage 201 are already known. Further, the voltage across the side Y+ and the side Y− can be detected by the analog-to-digital converter 40. Therefore, the resistance value between the side Y+ and the side Y− can be calculated by using the theorem of voltage division, so as to detect the variation of the resistance value between the side Y+ and the side Y−. Similarly, when the switches 121 and 122 are switched to the conducting state, and the multiplexers 131, 132 and 133 are respectively switched to 1, 0 and 0, the analog-to-digital converter 40 can measure the variation of the resistance value between the side X+ and the side X−. It should be noted that the persons of ordinary skill in the art can implement the voltage dividing resistance 201 with a smaller resistance value, so that a dynamic range of the input terminal of the analog-to-digital converter 40 may be prevented from being affected.
Moreover, when the event of one-point touching occurs, the switches 121 and 122 are switched to the conducting state, and the multiplexers 131, 132 and 133 are respectively switched to 0, 0 and 1, the analog-to-digital converter 40 can detect the position of the touch point in the Y direction. When the event of one-point touching occurs, the switches 121 and 122 are switched to the conducting state, and the multiplexers 131, 132 and 133 are respectively switched to 1, 1 and 0, the analog-to-digital converter 40 can detect the position of the touch point in the X direction.
Furthermore, when the event of multiple-point touching occurs, the switches 121 and 122 are switched to the conducting state, and the multiplexers 131, 132 and 133 are respectively switched to 0, 0 and 1, the analog-to-digital converter 40 can detect the position of the middle point with respect to the multiple points in the Y direction. When the event of multiple-point touching occurs, the switches 121 and 122 are switched to the conducting state, and the multiplexers 131, 132 and 133 are respectively switched to 1, 1 and 0, the analog-to-digital converter 40 can detect the position of the middle point with respect to the multiple points in the X direction. A table 1 is provided below for illustrating to the persons of ordinary skill in the art the functions of the detecting module 50 corresponding to the operation states of the switches 121 and 122 and the multiplexers 131˜133.
Please refer to
It should be known by the persons of ordinary skill in the art that the present invention is not limited to the aforesaid example regarding zooming in/out the photo displayed by the display device, as this example is merely an optional implementation for illustration. In other embodiments, the variation of the resistance value between the side Y+ and the side Y− can be applied to control the operation of every electronic device.
Further, the persons of ordinary skill in the art can construct a table illustrating the corresponding relationship of the distance between two touch points and the resistance value between the side Y+ and the side Y−. When the detecting module 50 detects the resistance value between the side Y+ and the side Y−, the distance between the two touching points can be obtained by looking up the table. Furthermore, the persons of ordinary skill can incorporate an interpolation method in the table to increase the resolution of the table. That is to say, if no matching data are found in the table, by looking up two adjacent resistance values to the resistance value, the distance between the two touching points can be obtained by performing the interpolation method.
Moreover,
Although the above embodiment has disclosed a possible type of the touch panel and the detecting method of multiple-point touching, it is common sense to the persons of ordinary skill in this art that different manufacturers may develop different designs of the touch panel and the detecting method of multiple-point touching, and the application of the present invention should not be limited to this type. In other words, as long as the variation of the resistance value of the resistance panel module is utilized to estimate the event of multiple-point touching, such implementations have conformed to the spirits of the present invention. Some other embodiments are further discussed hereinafter to allow people skilled in the art to recognize the spirit of the present invention and embody the present invention.
Please refer to
Please refer to
It is advantageous to do so because the variation of the resistance value between the side X+ and the side X− can serve as the input signal of the interface between the humans and the machines when the distance between the two touch points only varies in the X direction. On the other hand, the variation of the resistance value between the side Y+ and the side Y− can serve as the input signal of the interface between the humans and the machines when the distance between the two touch points only varies in the Y direction.
In summary, the present invention estimates the event of multiple-point touching by measuring the variation of the resistance value of the conducting path in the resistance panel module. Therefore, the variation of the resistance value can serve as the input signal of the interface between the humans and the machines to control the electronic device.
Although the present invention has been described with reference to the above embodiments, it will be apparent to one of the ordinary skill in the art that modifications to the described embodiment may be made without departing from the spirit of the invention. Accordingly, the scope of the invention will be defined by the attached claims not by the above detailed descriptions.
Number | Date | Country | Kind |
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96148681 | Dec 2007 | TW | national |