Patent Publication Number: US-2016231853-A1

Title: Touch panel and touch display device comprising the same

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefits of the Chinese Patent Application Serial Number 201510061892.0, filed on Feb. 6, 2015, the subject matter of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a touch panel and particularly to a touch panel in which the linearity and touch precision of the periphery of the touch panel may be improved and the cutting ratio of panel glass may be increased to reduce the production cost of the panel. 
     2. Description of Related Art 
     In recent years, with the trend to the development of user-friendly and simplified operation technology, display devices with touch panels have been widely used in daily life. Since users can input signals by touching the touch panels with fingers or other articles, the users&#39; dependence on other input devices, such as keyboards, mice, remote controllers, and the like, may be diminished or even eliminated. The convenience in operation can be drastically improved. 
     Conventionally, touch electrodes of a touch display panel have the same size. Accordingly, the touch electrodes in the periphery of the touch panel often encounter problems of poor linearity and precision. Thus, in some touch panels, the periphery of the touch panel is widened to solve the aforesaid problem. However, the widening will result in the reduction of the cutting ratio of panel glass and the cost for a single piece of glass will increase consequently. 
     Therefore, there is a need for an improved touch panel to solve the problems of poor peripheral linearity and precision as well as to increase glass cutting ratio to reduce production cost. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a touch panel, in which the area of a touch electrode disposed on a peripheral touch area is less than the area of a touch electrode disposed on a central touch area, to improve touch precision and to increase panel glass cutting ratio. 
     According to some embodiments, the touch panel comprises: a substrate having a first edge and a second edge adjacent to the first edge, and a central touch area and a first peripheral touch area outside the central touch area disposed on the substrate; a plurality of first touch electrodes disposed on the central touch area; a plurality of second touch electrodes disposed on the first peripheral touch area between the central touch area and the first edge; a plurality of third touch electrodes disposed on the first peripheral touch area between the central touch area and the second edge; and at least one fourth touch electrode disposed on the first peripheral touch area closest to an intersecting portion of the first edge and the second edge. An area of at least one of the first touch electrodes is greater than an area of at least one of the second touch electrodes, and the area of at least one of the first touch electrodes is greater than an area of at least one of the third touch electrodes. An area of at least one of the second touch electrodes is greater than an area of the fourth touch electrode, and an area of at least one of the third touch electrodes is greater than the area of the fourth touch electrode. 
     In a touch panel of an embodiment of the present invention, the first touch electrodes are arranged in an m×n array on the central touch area; the second touch electrodes are arranged in an m×n′ array on the first peripheral touch area between the central touch area and the first edge; the third touch electrodes are arranged in an m′×n array on the first peripheral touch area between the central touch area and the second edge; and the fourth touch electrode is or the fourth touch electrodes are arranged in an m′×n′ array on the first peripheral touch area closest to an intersecting portion of the first edge and the second edge. Each of m and n is an integer greater than 1, and each of m′ and n′ is an integer greater than or equal to 1. In some embodiments, m′ and n′ can be the same integer. In some embodiments, at least one of the second touch electrodes and at least one of the third touch electrodes can have the same area. 
     In a touch panel of an embodiment of the present invention, a border area is further disposed on the substrate outside the first peripheral touch area, and the touch panel may further comprise: a plurality of first border electrodes disposed on the border area between the first peripheral touch area and the first edge; a plurality of second border electrodes disposed on the border area between the first peripheral touch area and the second edge; and at least one third border electrode disposed on the border area closest to an intersecting portion of the first edge and the second edge. An area of at least one of the first border electrodes is greater than an area of the third border electrode, and an area of at least one of the second border electrodes is greater than an area of the third border electrode. An area of at least one of the first border electrodes may be less than or equal to an area of at least one of the second touch electrodes. An area of at least one of the second border electrodes may be less than or equal to an area of at least one of the third touch electrodes. An area of the third border electrode may be less than or equal to an area of the fourth touch electrode. In some embodiments, a ratio of a width of at least one of the first border electrodes to a width of at least one of the second touch electrodes is from 1:1 to 1:3; a ratio of a width of at least one of the second border electrodes to a width of at least one of the third touch electrodes is from 1:1 to 1:3; and/or a ratio of a width of the third border electrode to a width of the fourth touch electrode is from 1:1 to 1:3. 
     In a touch panel of an embodiment of the present invention, a second peripheral touch area may be further disposed on the substrate outside the first peripheral touch area and between the first peripheral touch area and the border area. The touch panel further comprises: a plurality of fifth touch electrodes disposed on the second peripheral touch area between the first peripheral touch area and the first edge; a plurality of sixth touch electrodes disposed on the second peripheral touch area between the first peripheral touch area and the second edge; and at least one seventh touch electrode disposed on the second peripheral touch area closest to an intersecting portion of the first edge and the second edge. An area of the seventh touch electrode is less than an area of at least one of the fifth touch electrodes, less than an area of at least one of the sixth touch electrodes, and less than an area of the at least one fourth touch electrode. In some embodiments, an area of at least one of the fifth touch electrodes and an area of at least one of the sixth touch electrodes can be the same. 
     In an embodiment, the fifth touch electrodes are arranged in an m×n″ array on the second peripheral touch area between the first peripheral touch area and the first edge; the sixth touch electrodes are arranged in an m″×n array on the second peripheral touch area between the first peripheral touch area and the second edge; and the seventh touch electrode is or the seven touch electrodes are arranged in an m″×n″ array on the second peripheral touch area closest to an intersecting portion of the first edge and the second edge. Each of m″ and n″ is an integer greater than or equal to 1. In some embodiments, m″ and n″ can be the same integer. 
     In a touch panel of an embodiment of the present invention, an area of at least one of the second touch electrodes may be greater or equal to an area of at least one of the fifth touch electrodes. In some embodiments, a ratio of a width of at least one of the fifth touch electrodes to a width of at least one of the second touch electrodes can be from 1:1 to 1:3. Likewise, in a touch panel of an embodiment of the present invention, an area of at least one of the third touch electrodes may be greater or equal to an area of at least one of the sixth touch electrodes. In some embodiments, a ratio of a width of at least one of the sixth touch electrodes to a width of at least one of the third touch electrodes can be from 1:1 to 1:3. In addition, in a touch panel of an embodiment of the present invention, an area of the fourth touch electrode may be greater or equal to an area of the seventh touch electrode. In some embodiments, a ratio of a width of the seven touch electrode to a width of the fourth touch electrode can be from 1:1 to 1:3. 
     In a touch panel of an embodiment of the present invention, a border area may be further disposed on the substrate outside the second peripheral touch area, and the touch panel may further comprise: a plurality of fourth border electrodes disposed on the border area between the second peripheral touch area and the first edge; a plurality of fifth border electrodes disposed on the border area between the second peripheral touch area and the second edge; and at least one sixth border electrode disposed on the border area closest to an intersecting portion of the first edge and the second edge. An area of at least one of the fourth border electrodes is greater than an area of the sixth border electrode, and an area of at least one of the fifth border electrodes is greater than an area of the sixth border electrode. In some embodiments, an area of at least one of the fourth border electrodes can be equal to an area of at least one of the fifth touch electrodes. Or, in some embodiments, an area of at least one of the fifth border electrodes can be equal to an area of at least one of the sixth touch electrodes. Or, in some embodiments, an area of the sixth border electrode can be equal to an area of the seventh touch electrode. 
     In a touch panel of an embodiment of the present invention, the pulse width for driving the fourth touch electrode is different from the pulse widths for driving the second touch electrodes and the third touch electrodes. The pulse widths for driving the second touch electrodes and the third touch electrodes are different from the pulse widths for driving the first touch electrodes. As a result, the final touch sensing signals perceived by the second touch electrodes, the third touch electrodes, and the fourth touch electrode are adjusted to be consistent with the touch sensing signals received by the first touch electrodes. Alternatively, a first gain is applied to a signal sensed by the first touch electrodes. A second gain is applied to a signal sensed by the second touch electrodes. A third gain is applied to a signal sensed by the third touch electrodes. A fourth gain is applied to a signal sensed by the fourth touch electrode. The fourth gain is different from each of the second gain and the third gain. The second gain and the third gain are each different from the first gain. The result is that the final touch sensing signals perceived by the second touch electrodes, the third touch electrodes, and the fourth touch electrode are adjusted to be consistent with the touch sensing signals received by the first touch electrodes. Alternatively, in addition to the utilization of different pulse widths for driving the first touch electrodes, the second touch electrodes, the third touch electrodes and the fourth touch electrode as described above, the first gain, the second gain, the third gain, and the fourth gain may be applied at the same time based on the signals sensed. 
     In a touch panel of an embodiment of the present invention, the peripheral linearity and precision may be improved through the disposition of touch electrodes in different sizes on the substrate. In particular, the area of the touch electrodes disposed on the peripheral touch area/areas is less than that of the touch electrodes disposed on the central touch area. Moreover, the touch electrode/electrodes closest to the intersecting portion of the two edges has/have the smallest area. In addition to the improvement of the peripheral linearity and precision, the panel glass cutting ratio may also be improved through the design in which the area of the border electrodes on the border area is less than that of the touch electrodes on the central touch area and the same as that of the touch electrodes on the peripheral touch area/areas. The additional utilization of different pulse widths for driving and the application of different gains may improve the resolution of coordinate reports to the system to improve touch precision. Furthermore, a touch display device is also provided in the present invention and it includes: a display panel; and a touch panel described above disposed on the display panel. 
     In the present invention, the type of display panel is not particularly limited. The display panel may be a liquid crystal display panel or an organic light-emitting diode display panel. 
     In the present invention, the “area” mentioned above means an area of a single touch electrode or a single border electrode. For example, an area of the first touch electrodes means an area of one of the first touch electrode. 
     Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top view of a touch panel of the Comparative Embodiment of the present invention; 
         FIG. 2  is a block diagram showing the operation of a touch panel of the Comparative Embodiment of the present invention; 
         FIG. 3  is a top view of a touch panel of Embodiment 1 of the present invention; 
         FIG. 4  is a schematic diagram showing the wiring for driving the touch electrodes of a touch panel of Embodiment 1 of the present invention; 
         FIG. 5  is a signal timing diagram of a touch panel of Embodiment 1 of the present invention; 
         FIG. 6  is a block diagram showing the operation of a touch panel of Embodiment 1 of the present invention; 
         FIG. 7  is a flow chart showing the operation of a touch panel of Embodiment 1 of the present invention; 
         FIG. 8  is a schematic top view of a touch panel of Embodiment 2 of the present invention; and 
         FIG. 9  is a schematic diagram of a touch display panel of Embodiment 3 of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention will be further described by the following embodiments in detail. It will be apparent to those skilled in the art to understand other advantages and functions of the present invention in view of the content disclosed herein. The present invention may also be used or applied in other different embodiments. Modifications and variations of the present invention may be made in the light of different viewpoints and applications without departing from the spirit of the present invention. 
     Comparative Embodiment 
       FIG. 1  is a top view of a touch panel of a Comparative Embodiment. In the touch panel of the Comparative Embodiment, a plurality of first touch electrodes  12  with the same size are disposed on a touch area  111  of a substrate  11 . As a result, the pitch (or the spacing) between every first touch electrodes  12  is the same in the Comparative Embodiment. Herein, the term “pitch” means the distance between the centers of two adjacent first touch electrodes  12 . 
       FIG. 2  is a block diagram showing the operation of a touch panel of the Comparative Embodiment. A microprocessor  24  (MCU) controls a driving circuit  22  to generate pulses for driving touch electrodes (not shown) in the touch panel  21 . Thereafter, signals sensed by sensing electrodes (not shown) in the touch panel  21  are received by a digital-to-analog converter  23  (ADC) and then transferred to the microprocessor  24  (MCU). The calculation is performed through an algorithm  25 . The resulting coordinates of points are reported to a system  26 . 
     In the Comparative Embodiment, the touch panel as shown in  FIG. 1  mainly works with a digital-to-analog converter having the same number of bits. However, with respect to the first touch electrodes  12  near a periphery area  112 , no real point is calculated by the algorithm. Thus, the peripheral linearity and precision are reduced, resulting in unsatisfied quality of touch control. Accordingly, in the Comparative Embodiment, the periphery area  112  needs to have a certain width to solve the aforesaid problem to improve the quality of touch control. However, when the periphery area  112  has a certain width, the panel cutting ratio will be lowered and the cost of a single panel will be increased. 
     Embodiment 1 
       FIG. 3  is a top view of a touch panel of Embodiment 1 of the present invention. A touch panel of the present embodiment includes a substrate  31  having a surface  311  and a first edge  31   a  and a second edge  31   b  in which the first edge  31   a  is adjacent to the second edge  31   b . A central touch area  311   a  and a first peripheral touch area  311   b  surrounding the central touch area  311   a  and outside the central touch area  311   a  are disposed on the surface  311  of the substrate  31 . A plurality of first touch electrodes  321  are disposed on the substrate  31  and on the central touch area  311   a . A plurality of second touch electrodes  322  are disposed on the substrate  31  and arranged on the first peripheral touch area  311   b  between the central touch area  311   a  and the first edge  31   a . A plurality of third touch electrodes  323  are disposed on the substrate  31  and arranged on the first peripheral touch area  311   b  between the central touch area  311   a  and the second edge  31   b . A plurality of fourth touch electrodes  324  are disposed on the substrate  31  and arranged on the first peripheral touch area  311   b  closest to an intersecting portion of the first edge  31   a  and the second edge  31   b . The area of the first touch electrodes  321  can be greater than that of the second touch electrodes  322 . The area of the second touch electrodes  322  can be greater than that of the fourth touch electrodes  324 . 
     In the present embodiment, the area of the second touch electrodes  322  can be the same as that of the third touch electrodes  323 . The only difference between the second touch electrodes  322  and the third touch electrodes  323  can be where the long sides and short sides of the rectangular touch electrodes are disposed. Nevertheless, these two areas may be different in other embodiments. 
     In addition, in the touch panel of the present embodiment, with respect to the width along the extension direction of the second edge  31   b , the width of the second touch electrodes  322  (the touch electrodes represented by B) can be a half of the width of the first touch electrodes  321  (the touch electrodes represented by A). With respect to the width along the extension direction of the first edge  31   a , the width of the third touch electrodes  323  (the touch electrodes represented by C) can be a half of the width of the first touch electrodes  321 . With respect to the fourth touch electrodes  324  (the touch electrodes represented by D), the widths thereof along the extension directions of the first edge  31   a  and the second edge  31   b  can be both half of the widths of the first touch electrodes  321 . Nonetheless, other embodiments of the present invention are not limited thereto. 
     In some embodiments, the area of at least one of the first touch electrodes  321  can be greater than the area of at least one of the third touch electrodes  323 . The area of at least one of the second touch electrodes  322  can be greater than an area of the fourth touch electrode  324 , and the area of at least one of the third touch electrodes  323  can be greater than the area of the fourth touch electrode  324 . 
     In some embodiments, the area of the second touch electrodes  322  and the area of the third touch electrodes  323  are each from a half to one fourth of the area of the first touch electrodes  321 , and the area of the fourth touch electrodes  324  can be from a half to one fourth of the area of the second touch electrodes  322  and from a half to one fourth of the area of the third touch electrodes  323 . For example, the area of the second touch electrodes  322  and the area of the third touch electrodes  323  can be each a half of the area of the first touch electrodes  321 , and the area of the fourth touch electrodes  324  can be a half of the area of the second touch electrodes  322  and a half of the area of the third touch electrodes  323 . 
     In addition, in the touch panel of the present embodiment, the substrate  31  may further have a third edge  31   c  and a fourth edge  31   d . The third edge  31   c  is opposite to the first edge  31   a  and the fourth edge  31   d  is opposite to the second edge  31   b . Accordingly, the substrate  31  in the present embodiment can be rectangular. When the substrate  31  is rectangular, some of the fourth touch electrodes  324  are arranged on the first peripheral touch area  311   b  closest to the intersecting portion of the first edge  31   a  and the second edge  31   b , some of the fourth touch electrodes  324  are arranged closest to the intersecting portion of the first edge  31   a  and the fourth edge  31   d , some of the fourth touch electrodes  324  are arranged closest to the intersecting portion of the third edge  31   c  and the second edge  31   b , and some of the fourth touch electrodes  324  are arranged closest to the intersecting portion of the third edge  31   c  and the fourth edge  31   d.    
     In the touch panel of the present embodiment, the first touch electrodes  321  can be arranged in an m×n array on the central touch area  311   a . The second touch electrodes  322  can be arranged in an m×n′ array on the first peripheral touch area  311   b  and in a region between the central touch area  311   a  and the first edge  31   a  and in a region between the central touch area  311   a  and the third edge  31   c , respectively. The third touch electrodes  323  can be arranged in an m′×n array on the first peripheral touch area  311   b  and in a region between the central touch area  311   a  and the second edge  31   b  and in a region between the central touch area  311   a  and the fourth edge  31   d , respectively. The fourth touch electrodes  324  can be arranged in an m′×n′ array on the first peripheral touch area  311   b  closest to the intersecting portion of the first edge  31   a  and the second edge  31   b , the intersecting portion of the first edge  31   a  and the fourth edge  31   d , the intersecting portion of the third edge  31   c  and the second edge  31   b , and the intersecting portion of the third edge  31   c  and the fourth edge  31   d . Each of m and n is an integer greater than 1 and each of m′ and n′ is an integer greater than or equal to 1. Furthermore, in some embodiments, m′ and n′ can be the same integer. 
     In other embodiments of the present invention, m, n, m′, and n′ are not limited to the numbers shown in  FIG. 3 . Instead, they can be adjusted according to the size of the touch panel and the touch precision. Nevertheless, the present invention is not limited thereto. 
     According to some embodiments, since the first touch electrodes  321 , the second touch electrodes  322 , the third touch electrodes  323 , and the fourth touch electrodes  324  have different sizes, the pitch (or the spacing) between every first touch electrodes  321  is different from the pitch (or the spacing) between every second touch electrodes  322 . The pitch (or the spacing) between every second touch electrodes  322  is also different from the pitch (or the spacing) between every fourth touch electrodes  324 . Herein, the term “pitch (or the spacing)” means the distance between the centers of two adjacent touch electrodes. 
     Furthermore, a border area  311   d  can be further disposed on the substrate  31  surrounding the first peripheral touch area  311   b  and outside the first peripheral touch area  311   b . Accordingly, the touch panel of the present embodiment further comprises: a plurality of first border electrodes  331  disposed on the border area  311   d  between the first peripheral touch area  311   b  and the first edge  31   a  and between the first peripheral touch area  311   b  and the third edge  31   c ; a plurality of second border electrodes  332  disposed on the border area  311   d  between the first peripheral touch area  311   b  and the second edge  31   b  and between the first peripheral touch area  311   b  and the fourth edge  31   d ; and a plurality of third border electrodes  333  disposed on the border area  311   d  closest to an intersecting portion of the first edge  31   a  and the second edge  31   b , an intersecting portion of the first edge  31   a  and the fourth edge  31   d , an intersecting portion of the third edge  31   c  and the second edge  31   b , and an intersecting portion of the third edge  31   c  and the fourth edge  31   d . An area of the first border electrodes  331  can be greater than that of the third border electrodes  333 . An area of the second border electrodes  332  can be also greater than that of the third border electrodes  333 . 
     Herein, the shape and area of the first border electrodes  331  (represented by B′) can be the same as those of the second touch electrodes  322  (represented by B). The shape and area of the second border electrodes  332  (represented by C′) can be the same as the third touch electrodes  323  (represented by C). The shape and area of the third border electrodes  333  (represented by D′) can be the same as the fourth touch electrodes  324  (represented by D). In other embodiments of the present invention, the area of the first border electrodes  331  may be from a half to one third of the area of the second touch electrodes  322 . In other embodiments, the area of the first border electrodes  331  can be from a half to one third of the area of the second touch electrodes  322 . The area of the second border electrodes  332  can be from a half to one third of the area of the third touch electrodes  323 . The area of the third border electrodes  333  can be from a half to one third of the area of the fourth touch electrodes  324 . 
     In other embodiments, a ratio of the width of the first border electrodes  331  to the width of the second touch electrodes  322  can be from 1:1 to 1:3. A ratio of the width of the second border electrodes  332  to the width of the third touch electrodes  323  can be from 1:1 to 1:3. A ratio of the width of at least one third border electrode  333  to the width of at least one fourth touch electrode  324  can be from 1:1 to 1:3. The width mentioned above can be the width along the extension direction of the first edge  31   a  or the second edge  31   b.    
     When the touch panel of the present embodiment works with a digital-to-analog converter having the same number of bits, since the area of the second touch electrodes  322 , the third touch electrodes  323 , and the fourth touch electrodes  324  on the first peripheral touch area  311   b  are less than the area of the first touch electrodes  321 , and the area of the first border electrodes  331 , the second border electrodes  332 , and the third border electrodes  333  on the border area  311   d  are less than the area of the first touch electrodes  321 , the peripheral linearity and precision of the touch panel can be improved to achieve satisfied touch quality without widening the periphery area as done in Comparative Embodiment. Thereby, compared to the touch panel of Comparative Embodiment, the panel glass cutting ratio can be improved and the cost for a single panel can be reduced. 
     In the present embodiment, the first touch electrodes  321 , the second touch electrodes  322 , the third touch electrodes  323 , and the fourth touch electrodes  324  have different areas. The touch signals can be adjusted according to the area sizes of the touch electrodes, in order to adjust the final touch sensing signals perceived by the second touch electrodes  322 , the third touch electrodes  323 , and the fourth touch electrodes  324  to be consistent with the touch sensing signals perceived by the first touch electrodes  321 . Likewise, the first touch electrodes  321 , the first border electrodes  331 , the second border electrodes  332 , and the third border electrodes  333  also have different sizes. The final sensing signals perceived by the first border electrodes  331 , the second border electrodes  332 , and the third border electrodes  333  can be adjusted to be consistent with the touch sensing signals perceived by the first touch electrodes  321 . For example, in order to achieve good touch quality, different gains can be applied in accordance with the calculation of algorithm, different driving waveforms, or adjustment of the sensed signals. 
     Please refer to  FIGS. 3-7 .  FIG. 4  is a schematic diagram showing the wiring for driving the touch electrodes of the touch panel of the present embodiment.  FIG. 5  is a signal timing diagram of the touch panel of the present embodiment.  FIG. 6  is a block diagram showing the operation of the touch panel of the present embodiment.  FIG. 7  is a flow chart showing the operation of the touch panel of the present embodiment. Herein, for clearer explanation, in  FIGS. 3-7 , the first touch electrodes  321  on the central touch area  311   a  are each represented by A; the second touch electrodes  322  on the first peripheral touch area  311   b  between the central touch area  311   a  and the first edge  31   a  and between the central touch area  311   a  and the third edge  31   c  respectively are each represented by B; the third touch electrodes  323  on the first peripheral touch area  311   b  between the central touch area  311   a  and the second edge  31   b  and between the central touch area  311   a  and the fourth edge  31   d  respectively are each represented by C; and the fourth touch electrodes  324  on the first peripheral touch area  311   b  closest to the intersecting portion of the first edge  31   a  and the second edge  31   b , the intersecting portion of the first edge  31   a  and the fourth edge  31   d , the intersecting portion of the third edge  31   c  and the second edge  31   b , and the intersecting portion of the third edge  31   c  and the fourth edge  31   d  are each represented by D. In addition, for clearer explanation, in  FIGS. 3-7 , the first border electrodes  331  on the border area  311   d  between the first peripheral touch area  311   b  and the first edge  31   a  and between the first peripheral touch area  311   b  and the third edge  31   c  respectively are each represented by B′; the second border electrodes  332  on the border area  311   d  between the first peripheral touch area  311   b  and the second edge  31   b  and between the first peripheral touch area  311   b  and the fourth edge  31   d  respectively are each represented by C′; and the third border electrodes  333  on the border area  311   d  closest to the intersecting portion of the first edge  31   a  and the second edge  31   b , the intersecting portion of the first edge  31   a  and the fourth edge  31   d , the intersecting portion of the third edge  31   c  and the second edge  31   b , and the intersecting portion of the third edge  31   c  and the fourth edge  31   d  are each represented by D′. Furthermore, some electrodes A, A′, B, B′, C, C′, D, and D′ shown in  FIG. 3  are omitted in  FIG. 4  and  FIG. 5 . Nonetheless, the person skilled in the art may understand that  FIGS. 3-5  are just schematic diagrams and the amount of touch electrodes included by the touch panel can be adjusted in accordance with, for example, panel size, panel area, touch precision, and so forth. 
     As shown in  FIGS. 4-6 , a driving circuit  62  is connected to the electrodes B, B′, D, and D′ of the touch panel  61  through signal transmission lines Tx(D 0 ), Tx(D 1 ), Tx(D 4 ), and Tx(D 5 ) and connected to the electrodes A, C, and C′ of the touch panel  61  through signal transmission lines Tx(D 2 ) and Tx(D 3 ). An integrating circuit  67  is connected to the electrodes D, D′, and C near the fourth edge  31  of the touch panel as shown in  FIG. 3  through signal receiving lines Rx( 1 ,D) and Rx( 1 ,C), respectively, connected to the electrodes B, B′, and A of the touch panel through signal receiving lines Rx( 2 ,B) and Rx( 2 ,A), respectively, and connected to the electrodes D′ and C′ near the second edge  31   b  of the touch panel as shown in  FIG. 3  through signal receiving lines Rx( 3 ,D) and Rx( 3 ,C), respectively. 
     As shown in  FIG. 4  and  FIG. 5 , in the driving circuit  62 , driving pulses are provided to electrodes A, B, B′, C, C′, D, and D′ through Tx(D 0 ) to Tx(D 5 ), respectively. The driving pulses with different pulse widths can be provided in accordance with the sizes of the electrodes A, B, B′, C, C′, D, and D′. This is to adjust the final touch sensing signals perceived by the second touch electrodes  322 , the third touch electrodes  323 , and the fourth touch electrodes  324  to be consistent with the touch sensing signals received by the first touch electrodes  321 . This is also to adjust the final sensing signals perceived by the first border electrodes  331 , the second border electrodes  332 , and the third border electrodes  333  to be consistent with the touch sensing signals received by the first touch electrodes  321  at the same time. 
     In the present embodiment, driving pulses with a pulse width Tx_ 1  are provided to the electrodes D and D′ through Tx(D 0 ), Tx(D  1 ), Tx(D 4 ), and Tx(D 5 ). Driving pulses with a pulse width Tx_ 2  are provided to the electrodes C and C′ through Tx(D 2 ) and Tx(D 3 ). 
     In some embodiments, a pulse width for driving at least one fourth touch electrode  324  (D) is different from a pulse width for driving the second touch electrodes  322  (B) and a pulse width for driving the third touch electrodes  323  (C). A pulse width for driving the second touch electrodes  322  (B) and a pulse width for driving the third touch electrodes  323  (C) are different from a pulse width for driving the first touch electrodes  321  (A). 
     In some embodiments, the area of the electrodes D and D′ is less than that of the electrodes C and C′, the pulse width Tx_ 1  provided to the electrodes D and D′ can be adjusted to be greater than the pulse width Tx_ 2  provided to the electrodes C and C′. In some embodiments, the area of the electrodes D and D′ can be a half of the area of the electrodes C and C′, the pulse width Tx_ 1  can be adjusted to be two times of the pulse width Tx_ 2 . Likewise, in some embodiments, driving pulses with a pulse width Tx_ 1  can be provided to the electrodes B and B′ through Tx(D 0 ), Tx(D 1 ), Tx(D 4 ), and Tx(D 5 ). Driving pulses with a pulse width Tx_ 2  can be provided to the electrode A through Tx(D 2 ) and Tx(D 3 ). The area of the electrodes B and B′ can be a half of the area of the electrode A. Accordingly, the pulse width Tx_ 1  can be adjusted to be two times of the pulse width Tx_ 2 . 
     Accordingly, as shown in  FIG. 3  and  FIG. 5 , in the present embodiment, when the corresponding third touch electrodes  323  (electrodes C), fourth touch electrodes  324  (electrodes D), second border electrode  332  (electrodes C′), and third border electrodes  333  (electrodes D′) are considered, the pulse widths driving the fourth touch electrodes  324  and the third border electrode  333  (electrodes D and D′) can be greater than the pulse widths driving the third touch electrodes  323  and the second border electrode  332  (electrodes C and C′). When the corresponding first touch electrodes  321  (electrodes A), second touch electrodes  322  (electrodes B), and first border electrodes  331  (electrodes B′) are considered, the pulse widths driving the second touch electrodes  322  (touch electrodes B) and the first border electrode  331  (electrodes B′) can be greater than the pulse width driving the first touch electrode  321  (electrodes A). 
     Regarding the receiving of the touch electrode signals, as shown in  FIG. 4  and  FIG. 5 , when the electrodes D′ as shown on the left side of the drawing are being driven, Rx( 1 ,D) senses and receives the touch signals of its adjacent electrodes D and D′. When the electrodes C′ as shown on the left side of the drawing are being driven, Rx( 1 ,C) senses and receives the touch signals of its adjacent electrodes C. When the electrodes B and B′ are being driven, Rx( 2 ,B) senses and receives the touch signals of the electrodes B and B′. When the electrodes A are being driven, Rx( 2 ,A) senses and receives the touch signals of the electrodes A. When the electrodes D and D′ as shown on the right side of the drawing are being driven, Rx( 3 ,D) senses and receives the touch signals of its adjacent electrodes D′. When the electrodes C as shown on the right side of the drawing are being driven, Rx( 3 ,C) senses and receives the touch signals of its adjacent electrodes C′. 
     Thereafter, in order to adjust the final touch sensing signals perceived by the second touch electrodes  322 , the third touch electrodes  323 , the fourth touch electrodes  324 , the first border electrodes  331 , the second border electrodes  332 , and the third border electrodes  333  to be consistent with the touch sensing signals received by the first touch electrodes  321 , different gains may be applied to the touch sensing signals sensed in accordance with the sizes of the touch electrodes A, B, B′, C, C′, D, and D′. As shown in  FIG. 6  and  FIG. 7 , when the integrating circuit  67  receives the touch signals of Rx( 1 ,C), Rx( 1 ,D), Rx( 2 ,A), Rx( 2 ,B), Rx( 3 ,C), and Rx( 3 ,D), it converts the charge signals sensed into voltage signals. The voltage signals are then transferred to a programmable gain amplifier  68  (PGA). At this time, as shown by  FIGS. 3 and 5-7 , a first gain (Gain  1 ) is applied to a sensing signal sensed by the first touch electrodes  321  (the touch electrodes A). A second gain (Gain  2 ) is applied to a sensing signal sensed by the second touch electrodes  322  and the first border electrodes  331  (the electrodes B and B′). A third gain (Gain  3 ) is applied to a sensing signal sensed by the third touch electrodes  323  and the second border electrodes  332  (the electrodes C and C′). A fourth gain (Gain  4 ) is applied to a sensing signal sensed by the fourth touch electrode  324  and the third border electrodes  333  (the electrodes D and D′). With regards to the corresponding electrodes C, C′, D, and D′, the fourth gain (Gain  4 ) can be greater than the third gain (Gain  3 ). With regards to the corresponding electrodes A, B, and B′, the second gain (Gain  2 ) can be greater than the first gain (Gain  1 ). 
     As shown in  FIG. 5  and  FIG. 6 , the final touch sensing signals perceived by the second touch electrodes  322 , the third touch electrodes  323 , the fourth touch electrodes  324 , the first border electrodes  331 , the second border electrodes  332 , and the third border electrodes  333  can be adjusted to be consistent with the touch sensing signals received by the first touch electrodes  321  through the adjustments of driving waveform and the application of different gains with respect to the sensing signals sensed. 
     Thereafter, as shown in  FIG. 6  and  FIG. 7 , the signals after the gains have been applied are converted by a digital-to-analog converter  63  (ADC) and then transferred to a microprocessor  64  (MCU). The data are calculated through an algorithm  69  and the resulting coordinates of points are reported to a system  66 . Herein, the microprocessor  64  further controls the driving circuit  62  in order to adjust the pulse widths of the touch electrodes. 
     In the touch panel of the present embodiment, the touch precision can be improved through the dynamic control of switching the pulse widths of the touch electrodes in combination with the applied gains. 
     Embodiment 2 
     As shown in  FIG. 8 , the structure and the driving mode of the touch panel in the present embodiment is similar to that of Embodiment 1. However, the touch panel of the present embodiment further includes a second peripheral touch area  311   c  surrounding the first peripheral touch area  311   b  and disposed outside the first peripheral touch area  311   b . The second peripheral touch area  311   c  can be between the first peripheral touch area  311   b  and the border area  311   d . Accordingly, the touch panel of the present embodiment further includes: a plurality of fifth touch electrodes  325  disposed on the second peripheral touch area  311   c  between the first peripheral touch area  311   b  and the first edge  31   a ; a plurality of sixth touch electrodes  326  disposed on the second peripheral touch area  311   c  between the first peripheral touch area  311   b  and the second edge  31   b ; and at least one seventh touch electrode  327  disposed on the second peripheral touch area  311   c  closest to an intersecting portion of the first edge  31   a  and the second edge  31   b.    
     In some embodiments, the plurality of fifth touch electrodes  325  are disposed on the substrate  31  and arranged on the second peripheral touch area  311   c  between the first peripheral touch area  311   b  and the first edge  31   a  and between the first peripheral touch area  311   b  and the third edge  31   c . The plurality of sixth touch electrodes  326  are disposed on the substrate  31  and arranged on the second peripheral touch area  311   c  between the first peripheral touch area  311   b  and the second edge  31   b  and between the first peripheral touch area  311   b  and the fourth edge  31   d . The plurality of seventh touch electrodes  327  are disposed on the substrate  31  and arranged on the second peripheral touch area  311   c  closest to an intersecting portion of the first edge  31   a  and the second edge  31   b , an intersecting portion of the first edge  31   a  and the fourth edge  31   d , an intersecting portion of the third edge  31   c  and the second edge  31   b , and an intersecting portion of the third edge  31   c  and the fourth edge  31   d . The area of the second touch electrodes  322  can be greater than that of the fifth touch electrodes  325 . The area of the third touch electrodes  323  can be greater than that of the sixth touch electrodes  326 . The area of the fourth touch electrodes  324  can be greater than that of the seventh touch electrodes  327 . The area of the first touch electrodes  321  can be greater than each of the area of the fifth touch electrodes  325  and the area of the sixth touch electrodes  326 . Each of the area of the fifth touch electrodes  325  and the area of the sixth touch electrodes  326  can be greater than the area of the seventh touch electrodes  327 . 
     Furthermore, in the touch panel of the present embodiment, the fifth touch electrodes  325  can be arranged in an m×n” array on the second peripheral touch area  311   c  between the first peripheral touch area  311   b  and the first edge  31   a  and the third edge  31   c , respectively. The sixth touch electrodes  326  can be arranged in an m″×n array on the second peripheral touch area  311   c  between the first peripheral touch area  311   b  and the second edge  31   b  and the fourth edge  31   d , respectively. The seventh touch electrodes  327  can be arranged in an m″×n″ array on the second peripheral touch area  311   c  closest to an intersecting portion of the first edge  31   a  and the second edge  31   b , an intersecting portion of the first edge  31   a  and the fourth edge  31   d , an intersecting portion of the third edge  31   c  and the second edge  31   b , and an intersecting portion of the third edge  31   c  and the fourth edge  31   d . Each of m″ and n″ can be an integer greater than or equal to 1. Herein, the numbers of m″ and n″ are not particularly limited to the numbers shown in  FIG. 8 . They can be adjusted in accordance with the sizes of the touch panel and the touch precision. Nevertheless, the present invention is not limited thereto. 
     In addition, in the touch panel of the present embodiment, a border area  311   d  can be further disposed on the substrate  31  outside the second peripheral touch area  311   c . Accordingly, the touch panel of the present embodiment further includes: a plurality of fourth border electrodes  334  disposed on the border area  311   d  between the second peripheral touch area  311   c  and the first edge  31   a  and the third edge  31   c , respectively; a plurality of fifth border electrodes  335  disposed on the border area  311   d  between the second peripheral touch area  311   c  and the second edge  31   b  and the fourth edge  31   d , respectively; and a plurality of sixth border electrodes  336  disposed on the border area  311   d  closest to an intersecting portion of the first edge  31   a  and the second edge  31   b , an intersecting portion of the first edge  31   a  and the fourth edge  31   d , an intersecting portion of the third edge  31   c  and the second edge  31   b , and an intersecting portion of the third edge  31   c  and the fourth edge  31   d . Each of the area of the fourth border electrodes  334  and the area of the fifth border electrodes  335  can be greater than that of the sixth border electrodes  336 . 
     In addition, in the touch panel of the present embodiment, a ratio of a width of the fifth touch electrode  325  to a width of the second touch electrode  322  along the extension direction of the second edge  31   b  can be from 1:1 to 1:3. For example, this ratio can be 1:2. In addition, a ratio of a width of the sixth touch electrode  326  to a width of the third touch electrode  323  along the extension direction of the first edge  31   a  can be from 1:1 to 1:3. For example, this ratio can be 1:2. In addition, a ratio of a width of the seventh touch electrode  327  to a width of the fourth touch electrode  324  along each extension direction of the first edge  31   a  and the second edge  31   b  can be from 1:1 to 1:3. For example,this ratio can be 1:2. 
     In addition, in the touch panel of the present embodiment, a ratio of a width of the fourth border electrode  334  to a width of the fifth touch electrode  325  can be from 1:1 to 1:3. A ratio of a width of the fifth border electrode  335  to a width of the sixth touch electrode  326  can be from 1:1 to 1:3. A ratio of a width of the sixth border electrode  336  to a width of the seventh touch electrode  327  can be from 1:1 to 1:3. In the present embodiment, the shape and area of the fourth border electrodes  334  can be the same as those of the fifth touch electrodes  325 . The shape and area of the fifth border electrodes  335  can be the same as those of the sixth touch electrodes  326 . The shape and area of the sixth border electrodes  336  can be the same as those of the seventh touch electrodes  327 . 
     In the aforesaid Embodiments 1 and 2 of the present invention, rectangular touch panels are taken as examples; however, other embodiments of the present invention are not limited thereto. In other embodiments of the present invention, the substrates may be in other shapes, such as pentagons, hexagon, and so forth. The only limitation is that the touch electrodes disposed on the first peripheral touch area and/or the second peripheral touch area closest to an intersecting portion of two edges have smaller shapes than the first touch electrodes on the central touch area. 
     Embodiment 3 
     As shown in  FIG. 9 , the present embodiment provides a touch display device including a display panel  92  and a touch panel  91  disposed on the display panel  92 . The touch panel  91  may be one of the touch panels described above in the aforesaid embodiments. The display panel  92  may be a conventional display panel, such as a liquid crystal display panel or an organic light-emitting diode display panel. 
     The touch panel and the display panel made in the aforesaid embodiments of the present invention may be applied to any conventional electronic devices requiring touch control function, especially to touch display devices, such as display devices, mobile phones, notebooks, video cameras, cameras, music players, portable navigation devices, televisions, and so forth. 
     Although the present invention has been explained in relation to its preferred embodiments, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.