Patent Publication Number: US-2011057905-A1

Title: Touch Panel and Inspection Method Thereof

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application No. PCT/CN2009/075756 filed on Dec. 21, 2009. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a touch panel and an inspection method thereof, more particularly, to a touch panel with sensing lines that can be inspected separately and an inspection method thereof. 
     2. Description of the Prior Art 
     Along with the development of technology, notebooks, mobile phones, portable media players and other electronic devices are gradually utilizing touch panels to replace traditional keyboards as a new generation of an input interface. Conventional touch panels can be divided into capacitive touch panels and resistive touch panels. Due to the multi-touch function, the capacitive touch panels are receiving much attention. 
     In general, the capacitive touch panel includes a plurality of sensing lines formed on the surface of the substrate. When a user uses its finger or a conductive object to approach or touch the surface of the capacitive touch panel, the capacitance value of the sensing lines will change correspondingly. The touch location on the touch panel can therefore be sensed and calculated by sensing the change of the capacitance value. It is known that the sensing accuracy of the capacitive touch panel depends largely on the electrical characteristics of each sensing line. Therefore, if there are open circuits, short circuits or the phenomenon of uneven capacitance effects in the sensing lines, the touch sensing accuracy will be affected. Accordingly, the inspection of the sensing lines becomes very important. 
     Chinese patent application publication number CN101408825 disclosed a method of inspecting a semi-finished product of a touch panel. However, the inspection method in this patent requires additional inspecting lines on the semi-finished product of the touch panel, therefore decreasing the utilization efficiency of the substrate. Moreover, the inspection method inspects the sensing lines together with the corresponding connecting wires, but it is unable to inspect the electrical characteristics of the sensing lines individually. Chinese patent number CN100498483 disclosed a method of inspecting the terminal parts of an active matrix substrate. However, the inspection method can not inspect the sensing lines individually when applied to the capacitive touch panels. In short, the above-mentioned patents are unable to detect the defects of the sensing lines precisely, and are prone to be affected by the interference of high resistance RC effect of the connecting wires, which might affect the actual capacitance measurements. And due to the large deviation of the measurements, pseudo-defects can easily occur in the subsequent inspecting processes. Consequently, effectively inspecting the sensing lines of the capacitive touch panels to maintain the quality of capacitive touch panels remains an important issue in this field. 
     SUMMARY OF THE INVENTION 
     The present invention provides a touch panel, wherein an inspecting region exposed by an insulation layer is provided on the end of the sensing lines for inspection. 
     The present invention provides an inspection method which is able to precisely detect the capacitance value and the resistance value of the sensing lines. 
     The present invention provides an inspection method which is able to detect the resistance value of the connecting wires precisely. 
     The present invention provides a touch panel, including a substrate, a plurality of first sensing lines, a plurality of first connecting wires corresponding to the first sensing lines, a plurality of second sensing lines, a plurality of second connecting wires corresponding to the second sensing lines, and an insulation layer. The first sensing lines are disposed on the substrate. Each first sensing line extends along a first direction and at least one end of each first sensing line includes a first inspecting region. The second sensing lines are disposed on the substrate. At least one end of each second sensing line includes a second inspecting region and each second sensing line extends along a second direction. The first direction is not parallel to the second direction. The insulation layer covers the first sensing lines and the second sensing lines and exposes the first inspecting regions and the second inspecting regions. 
     In one embodiment of the present invention, the above mentioned insulation layer includes a plurality of openings. The openings expose the first inspecting regions and the second inspecting regions correspondingly. 
     In one embodiment of the present invention, each above mentioned first sensing line and each above mentioned second sensing line are formed by a plurality of sensing pads and a plurality of bridge parts. The sensing pads include a plurality of center sensing pads and two peripheral sensing pads. The center sensing pads are connected to each other by the bridge parts and are disposed between the two peripheral pads. The first inspecting region or the second inspecting region is disposed in the peripheral sensing pads. The substrate includes a display region and a non-display region, and each peripheral sensing pad includes an outer part and an inner part. The outer part is disposed in the non-display region while the inner part and the center sensing pads are disposed in the display region. In addition, the first inspecting region or the second inspecting region is in the outer part. 
     In one embodiment of the present invention, the above mentioned substrate includes a first sensing region and a second sensing region. A portion of the first sensing lines and a portion of the second sensing lines are disposed in the first sensing region. Other portions of the first sensing lines and other portions of the second sensing lines are disposed in the second sensing region. The second sensing lines in the first sensing region are aligned with the second sensing lines in the second sensing region. 
     In one embodiment of the present invention, the above mentioned first sensing lines are disposed on a first side of the substrate and the second sensing lines are disposed on a second side of the substrate. The first side and the second side are disposed opposite to each other. In one embodiment, each first sensing line is formed by a sensing bar and each second sensing line is formed by a sensing bar. Moreover, the touch panel further includes a plurality of dummy pads disposed on the first side of the substrate and between each of the first sensing lines. Specifically, the insulation layer includes a first insulation layer and a second insulation layer. The first insulation layer covers the first sensing lines and exposes the first inspecting regions. The second insulation layer covers the second sensing lines and exposes the second inspecting regions. The first insulation layer, for example, includes a plurality of first openings to expose the first inspecting regions, and the second insulation layer, for example, includes a plurality of second openings to expose the second inspecting regions. 
     In one embodiment of the present invention, the above mentioned touch panel further includes a plurality of first connecting wires and a plurality of second connecting wires. A first connecting terminal of each first connecting wire connects to one of the first sensing lines, and a second connecting terminal of each second connecting wire connects to one of the second sensing lines. The insulation layer further covers the first connecting wires and the second connecting wires. Besides, the insulation layer further exposes a signal terminal of each first connecting wire and a second signal terminal of each second connecting wire. 
     The present invention further provides an inspection method of a touch panel. The inspection method includes providing the above mentioned touch panel and performing an inspecting process to inspect two inspecting regions of the groups consisting of the first inspecting regions and/or the second inspecting regions. 
     In one embodiment of the present invention, the above mentioned inspecting process further includes inspecting one of the first inspecting regions and one of the second inspecting regions. 
     In one embodiment of the present invention, both ends of each first sensing line include the first inspecting regions. The inspecting process includes inspecting the two first inspecting regions on two ends of the same first sensing line. 
     In one embodiment of the present invention, both ends of each second sensing line include the second inspecting regions. The inspecting process includes inspecting the two second inspecting regions on two ends of the same second sensing line. 
     The present invention further provides an inspection method of a touch panel. The inspection method includes providing the above mentioned touch panel, then performing an inspecting process to inspect one of the first inspecting regions and the corresponding first signal terminal, or to inspect one of the second inspecting regions and the corresponding second signal terminal. 
     In light of above, the inspecting regions in the present invention are disposed on the ends of the sensing lines in the touch panel in the present invention, and the insulation layer exposes the inspecting regions. Therefore, in the touch panel of the present invention, the sensing lines can be inspected individually, and the defects of the sensing lines can be detected more accurately without being interfered with by high-resistance RC properties of the connecting wires, which might affect the actual capacitance measurements. In addition, in the touch panel of the present invention, the connecting wires can also be inspected individually to more accurately detect the defects of the touch panel. With the above mentioned touch panel structure, the inspection method of the present invention can more efficiently detect the defects of the sensing lines and the connecting wires. 
     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram showing a top view of the first embodiment of the touch panel in the present invention. 
         FIG. 2  is a schematic diagram of the region I in  FIG. 1 . 
         FIG. 3  is a schematic diagram showing a cross-sectional view along the AA′ line in  FIG. 2 . 
         FIG. 4  is a schematic diagram showing a top view of the second embodiment of the touch panel in the present invention. 
         FIG. 5  is a schematic diagram of region II in  FIG. 4 . 
         FIG. 6  is a schematic diagram showing a cross-sectional view along the BB′ line in  FIG. 5   
         FIG. 7  is a schematic diagram showing a top view of the third embodiment of the touch panel in the present invention. 
         FIG. 8  is a schematic diagram showing a top view of the fourth embodiment of the touch panel in the present invention. 
         FIG. 9  is a schematic diagram showing a cross-sectional view of the fifth embodiment of the touch panel in the present invention. 
         FIG. 10  is a schematic diagram showing a top view of the first side of the touch panel. 
         FIG. 11  is a schematic diagram showing a top view of the second side of the touch panel. 
         FIG. 12  shows a first inspection method of one embodiment of the touch panel in the present invention. 
         FIG. 13  shows a second inspection method of one embodiment of the touch panel in the present invention. 
         FIG. 14  shows a third inspection method of one embodiment of the touch panel in the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     To provide a better understanding of the presented invention, preferred embodiments will be described in detail. The preferred embodiments of the present invention are shown in the accompanying drawings with numbered elements. 
       FIG. 1  is a schematic diagram showing a top view of the first embodiment of the touch panel in the present invention. Please refer to  FIG. 1 . The touch panel  100  includes a substrate  110 , a plurality of first sensing lines  120 , a plurality of second sensing lines  130  and an insulation layer  140 . The first sensing lines  120  and the second sensing lines are both disposed on the substrate  110 . Each first sensing line  120  extends along a first direction D 1 , and each second sensing line  130  extends along a second direction D 2 . The first direction D 1  is not parallel to the second direction D 2 . The first sensing lines  120  can be perpendicular to the second sensing lines  130 . In addition, at least one end of each first sensing line  120  includes a first inspecting region  150 , and at least one end of each second sensing line  130  includes a second inspecting region  160 . The insulation layer  140  covers the first sensing lines  120  and the second sensing lines  130  and exposes the first inspecting regions  150  and the second inspecting regions  160 . 
     In the present embodiment, both ends of each first sensing line  120  include the first inspecting regions  150  while both ends of each second sensing line  130  include the second inspecting regions  160 . In another embodiment, only one end of each first sensing line  120  includes the first inspecting region  150  while only one end of each second sensing line  130  includes the second inspecting region  160 . In addition, the insulation layer  140  in the present embodiment includes a plurality of openings  142 . The shape of openings  142  can be round, oval, rectangular, polygonal, or other varieties of closed shapes formed by curves. Each opening  142  exposes one first inspecting region  150  or exposes one second inspecting region  160 . 
     Moreover, the touch panel  100  further includes a plurality of first connecting wires S 1  and a plurality of second connecting wires S 2 . A first connecting terminal S 1   a  of each first connecting wire S 1  connects to one of the first sensing lines  120 , and a second connecting terminal  52   a  of each second connecting wire S 2  connects to one of the second sensing lines  130 . The other end of each first connecting wire S 1  is a first signal terminal S 1   b  and the other end of each second connecting wire S 2  is a second signal terminal  52   b . The above mentioned connecting wires are integrated into a side of the non-display region of the substrate no by arranging the layout of the connecting wires. All the signal terminals of the connecting wires are connected to a driving chip (not shown). 
     In the present embodiment, the insulation layer  140  further covers the first connecting wires S 1  and the second connecting wires S 2 . Besides, the insulation layer  140  further exposes each first signal terminal S 1   b  and each second signal terminal  52   b . In other words, a portion of the openings  142  of the insulating layer  140  are disposed on the first signal terminals S 1   b  and the second signal terminals  52   b  in order to expose the first signal terminals S 1   b  and the second signal terminals  52   b.    
     In such a design, when inspecting the touch panel  100 , the sensing lines  120 ,  130  and the connecting wires S 1 , S 2  can be inspected separately. In other words, when inspecting the sensing lines  120 ,  130 , the inspecting results will not be affected by the defects of the connecting wires S 1 , S 2 . Similarly, when inspecting the connecting wires S 1 , S 2 , the inspecting results will not be affected by the defects of sensing lines  120 ,  130 . Therefore, the present embodiment can detect the defects of different components in the touch panel  100  more efficiently, and can improve the quality of touch panel  100 . 
     In detail, each first sensing line  120  and each second sensing line  130  in the present embodiment are formed by a plurality of sensing pads  170  and a plurality of bridge parts (not shown in  FIG. 1 ). The sensing pads  170  include a plurality of center sensing pads  172  and two peripheral sensing pads  174 . The center sensing pads  172  are connected to each other and are disposed between the two peripheral pads  174 . The first inspecting region  150  or the second inspecting region  160  is disposed in the two peripheral sensing pads  174 . That is, both ends of the first sensing lines  120  and both ends of the second sensing lines  130  are composed of the peripheral sensing pads  174 . 
     In the present embodiment, the size of the first inspecting region  150  and the second inspecting region  160  can be determined by the design of the peripheral sensing pads  174 . In general, if the peripheral sensing pads  174  have enough large areas, the inspecting process for alignment may be easier. That is, the inspection of the touch panel  100  does not require high-precision alignment equipment and the inspection method can be simplified and speedier. 
       FIG. 2  is a schematic diagram of the region I in  FIG. 1 , and  FIG. 3  is a schematic diagram showing a cross-sectional view along the A-A′ line in  FIG. 2 . Please refer to  FIG. 2  and  FIG. 3 . In the present embodiment, the adjacent center sensing pads  172  can be connected by a bridge part  176 . Certainly, the center sensing pad  172  and the peripheral sensing pad  174  can also be connected by the bridge part  176 . 
     In addition, as shown in  FIG. 3 , the peripheral sensing pad  174  and the center sensing pad  172  can be further connected by the bridge part  176 . However, according to different requirements, it is available to only connect the peripheral sensing pad  174  and the center sensing pad  172  in the second sensing lines  130 , or only connect the plurality of center sensing pads  172 . It is worth noting that the first sensing lines  120  and the second sensing lines  130  should be insulated from one another. Accordingly, an insulation component  180  is disposed between the bridge part  176  of the first sensing line  120  and the bridge part  176  of the second sensing line  130 . 
     The insulation layer  140  in the present embodiment exposes the first inspecting regions  150 , the second inspecting regions  160 , the first signal terminals S 1   b  and the second signal terminals  52   b . Therefore, an inspection of the electrical characteristics of the touch panel  100  can be carried out by using the regions exposed by the insulation layer  140 . In this way, the sensing lines  120 ,  130  and the connecting wires S 1 , S 2  can be inspected separately. In addition, the inspection method of the touch panel  100  is quite simple, and once the defects are detected, it can be repaired in time. Therefore, the touch panel  100  can have good quality. 
       FIG. 4  is a schematic diagram showing a top view of the second embodiment of the touch panel  400  in the present invention.  FIG. 5  is a schematic diagram of region II in  FIG. 4 , while  FIG. 6  is a schematic diagram showing a cross-sectional view along B-B′ line in  FIG. 5 . Please refer to  FIG. 4 ,  FIG. 5  and  FIG. 6 . The touch panel  400  is similar to the touch panel  100  in the first embodiment. The touch panel  400  also includes a substrate  110 , a plurality of first sensing lines  120 , a plurality of second sensing lines  130 , and an insulation layer  140 . However, in the touch panel  400 , the substrate  110  includes a display region  112  and a non-display region  114 . In addition, the peripheral sensing pad  474  includes an outer part  474 A and an inner part  474 B. The outer part  474 A is located in the non-display region  114 , while the inner part  474 B and the center sensing pads  172  are located in the display region  112 . Moreover, the first inspecting region  150  and the second inspecting region  160  are located in the outer part  474 A. 
     Generally speaking, the center sensing pads  172  and the peripheral sensing pads  174  are made by transparent conductive material so as to provide good light transmission for the touch panel  400 . When inspecting the touch panel  400 , a probe is used by the operator to contact the first inspecting region  150  or the second inspecting region  160  for inspection. However, the movement and contact of the probe may cause damage to the transparent conductive material and thus affect the surface flatness of the first inspecting regions  150  or the second inspecting regions  160 . As such, the first inspecting regions  150  and the second inspecting regions  160  in the present embodiment are disposed in the non-display region  114  so as to avoid the light transmittance of the display region  112  being affected. That is, the touch panel  400  not only has good electrical characteristics but also has good light transmittance. 
       FIG. 7  is a schematic diagram showing a top view of the third embodiment of the touch panel in the present invention. Please refer to  FIG. 7 . The touch panel  700  modifies the insulation layer  140  in the touch panel  400  to form a circular opening  442 . The circular opening  442  exposes all of the first inspecting regions  150  and all of the second inspecting regions  160 . In other words, the circular opening  442  is designed to link together all the openings  142  in the second embodiment. 
     However, in another embodiment, it is also available to link a potion of the openings  142  of the insulation layer  140  and to expose a portion of the first inspecting regions  150  or a portion of the second inspecting regions  160  through the linked openings. The first inspecting regions  150  and the second inspecting regions  160  in the present embodiment are exposed such that the defects of the first sensing lines  120  and the second sensing lines  130  can be detected when inspecting the touch panel  700 . The touch panel  700  therefore has good quality. 
       FIG. 8  is a schematic diagram showing a top view of the fourth embodiment of the touch panel in the present invention. Please refer to  FIG. 8 . The touch panel  800  also includes a substrate  110 , a plurality of first sensing lines  120 , a plurality of second sensing lines  130  and an insulation layer  140 . However, in the present embodiment, the substrate  110  includes a first sensing area  116  and a second sensing area  118 . A portion of the first sensing lines  120  and a portion of the second sensing lines  130  are disposed in the first sensing area  116 , while the other portion of the first sensing lines  120  and the other portion of the second sensing lines  130  are disposed in the second sensing area  118 . Besides, the second sensing lines  130  in the first sensing area  116  are aligned with the second sensing lines  130  in the second sensing area  118 . That is, one of the second sensing lines  130  in the first sensing region  116  and one of the second sensing lines  130  in the second sensing region  118  are arranged in a straight line. 
     According to the configuration in the present embodiment, two second sensing lines  130  are aligned such that the sensor error such as ghost point phenomenon can be avoided when touching the touch panel  800 . Moreover, the peripheral sensing pad  874 A has similar structure with the peripheral sensing pad  474  in the second embodiment, which is formed by the inner part  474 A and the outer part  474 B. The peripheral sensing pad  874 B, for example, has a triangular pattern. It is worth noting that the second inspecting region  160  is disposed on only one end of the second sensing line  130  in the present embodiment, while there is no inspecting region disposed on center of the display region. In other words, there is no inspecting region disposed in the peripheral sensing pad  874 B. Such a design helps improve light transmission of the touch panel  800 . Similarly, in the touch panel  800  of the present embodiment, the capacitance value of the sensing lines  120 ,  130  can be inspected individually, so a good quality of the touch panel  800  can be achieved. 
       FIG. 9  is a schematic diagram showing a cross-sectional view of the fifth embodiment of the touch panel in the present invention.  FIG. 10  is a schematic diagram showing a top view of the first side of the touch panel and  FIG. 11  is a schematic diagram showing a top view of the second side of the touch panel. Please refer to  FIG. 9 . The touch panel  900  includes a substrate  910 , a plurality of first sensing lines  920 , a plurality of second sensing lines  930 , a first insulation layer  945  and a second insulation layer  847 . The first sensing lines  920  and the second sensing lines  930  are disposed on the substrate  910 . In particular, the first sensing lines  920  are disposed on a first side  912  of the substrate  910 , while the second sensing lines  930  are disposed on a second side  914  of the substrate  910 . The first side  912  and second side  914  are disposed opposite to each other. 
     Please refer to  FIG. 9 ,  FIG. 10  and  FIG. 11 . Each first sensing line  920  extends along the first direction D 1 , and each second sensing line  930  extends along the second direction D 2 , where the first direction D 1  and the second direction of D 2  are not parallel. In addition, two first inspecting regions  950  are disposed respectively on two ends of the first sensing lines  920  and two second inspecting regions  960  are disposed respectively on two ends of the second sensing lines  930 . The first insulation layer  945  covers the first sensing lines  920  and exposes the first inspecting regions  950 . The second insulation layer  947  covers the second sensing lines  930  and exposes the second inspecting regions  960 . 
     In detail, each first sensing line  920  is formed by a sensing bar and each second sensing line  930  is formed by a sensing bar. In other words, each first sensing line  920  and each second sensing line  930  are formed by a conductive bar-type pattern which includes, for example, transparent conductive material. Besides, in order to improve the uniformity of brightness of the touch panel  900 , the touch panel  900  further includes a plurality of dummy pads  922  disposed on the first side  912  of the substrate  910  and is located between the first sensing lines  920 . 
     In the present embodiment, the first insulation layer  945  includes a plurality of first openings  945 A to expose the first inspecting regions  950 . The second insulation layer  947  includes a plurality of second openings  947 A to expose the second inspecting regions  960 . Particularly, all the second openings  947 A are disposed outside the display region  112 . In another embodiment, the first openings  945 A in the same side can be linked together and the second openings  947 A in the same side can also be linked together. The first openings  945 A and the second openings  947 A expose their corresponding first inspecting regions  950  and their corresponding second inspecting regions  960 , so the first sensing lines  920  and the second sensing lines  930  can be inspected separately. Therefore, the defects of the touch panel  900  can be detected correctly, being able to maintain the quality of the touch panel  900 . 
     In addition, in the present embodiment, the first inspecting regions  950  are disposed on both ends of each first sensing line  920 , and the second inspecting regions  960  are disposed on both ends of each second sensing line  930 . However, according to different inspecting requirements and different layout designs, the first inspecting regions  950  are disposed on only one end of each first sensing line  920 , and the second inspecting regions  960  are disposed on only one end of each second sensing line  930 . 
     The touch panels  100 ,  400 ,  700 ,  800  and  900  described in the above mentioned embodiments respectively provide the inspecting regions on the end of each sensing line. These inspecting regions are exposed by the insulation layer. Therefore, a simple inspection method can be used for the touch panels  100 ,  400 ,  700 ,  800  and  900  to respectively detect whether there are defects between each sensing line or each connecting wire. Specifically, the inspection methods that can be used for the touch panels  100 ,  400 ,  700 ,  800  and  900  are shown as follows.  FIG. 12  shows a first inspection method of one embodiment of the touch panel in the present invention. Please refer to  FIG. 12 . Step  10  is carried out firstly by providing a touch panel. In the inspection method of the present embodiment, the touch panel includes, for example, one of the aforementioned touch panels  100 ,  400 ,  700 ,  800  and  900  or one of the touch panels  100 ,  400 ,  700 ,  800  and  900  whose inspecting regions are disposed only on one end of each sensing line. 
     Then, step  20  is carried out to perform an inspecting process to inspect the first inspecting region of one of the first sensing lines and the second inspecting region of one of the second sensing lines. Specifically, the inspection process includes, for example, using a probe to respectively contact the first inspecting region of one of the first sensing lines and to contact the second inspecting region of one of the second sensing lines. Next, the capacitance value between the set of probes is measured. Then it is determined whether there is a short circuit or an open circuit on the first sensing lines or the second sensing lines according to the measured capacitance values. 
     In addition, when the patterns of the first sensing lines or the patterns of the second sensing lines are inconsistent due to some manufacturing process errors, for example, the size differences between the patterns are too large or the space between each patterns are inconsistent, these errors will change the capacitive coupling effect of the first sensing lines and the second sensing lines at different locations, leading to inaccurate measurements of the touch panel. The present embodiment can detect whether there are defects of the patterns of the sensing lines according to the change of the capacitance values between different sensing lines, and further fix the defects so as to enhance the sensing accuracy of the touch panel. 
     The inspection methods of the present embodiment can directly detect the capacitance value between different sensing lines when accompanying with the layout arrangement of the touch panels  100 ,  400 ,  700 ,  800  and  900 . The inspection method is not affected by the connecting wires so the defects of the sensing lines can be detected more directly. That is, the defects of the sensing lines can be detected correctly and efficiently. 
       FIG. 13  shows a second inspection method of one embodiment of the touch panel in the present invention. Please refer to  FIG. 13 . The inspection method of a touch panel in the present embodiment includes, for example, performing step  10  by providing a touch panel. In this embodiment, the touch panel includes, for example, one of the aforementioned touch panels  100 ,  400 ,  700 ,  800  and  900 . It is noted that, in the touch panel for the inspection method in the present embodiment, both ends of the sensing lines include the inspecting regions. 
     Then, step  30  is carried out by performing an inspecting process to inspect the inspecting regions at respectively two ends in one sensing line. By inspecting the resistance value of one sensing line through the inspecting regions on both ends of the sensing line, a short circuit or an open circuit defect of each sensing line can be detected. Moreover, if the difference of the connecting impedance of the sensing lines is too large, it can also be detected in step  30 . 
     For example, when the method is applied to the touch panel  100 , the probe can simultaneously contact the first inspecting regions  150  on both ends in the same first sensing line  120 . Of course, the probe can also simultaneously access the second inspecting regions  160  on both ends in the same second sensing line  130 . In such an inspecting process, the resistance value error in one of the sensing lines can be detected correctly and the corresponding repair work can be carried out. Thus, the quality of the touch panel can be improved by using such inspection method. 
     The aforementioned two kinds of inspection methods can effectively detect the defects within the sensing lines, but the electrical characteristics of the connecting wires in the touch panel should also be maintained to provide normal touch panel sensing function. Therefore, the present embodiment provides the following inspection method which is directed to inspect the connecting wires in the touch panel.  FIG. 14  shows a third inspection method of one embodiment of the touch panel in the present invention. Please refer to  FIG. 14 . In the inspection method of the present embodiment, step  10  is carried out firstly by providing a touch panel. The touch panel includes one of the aforementioned touch panels  100 ,  400 ,  700 ,  800  and  900 . It is noted that, in the touch panels used in this inspection method, the insulation layer exposes the signal terminals of the connecting wires. In addition, the inspecting region could be disposed only on the end of each sensing line that connects to the signal line. 
     Then, step  40  is carried out by performing an inspecting process to inspect one of the inspecting region and the corresponding signal terminal. For example, when the inspection method is applied to the touch panel  100 , the step  40 , for example, uses a probe to contact one of the first inspecting region  150  or the second inspecting region  160 , and uses another probe to contact the corresponding first signal terminal S 1   b  or the corresponding second terminal  52   b . In this way, by using two probes to inspect the electrical characteristics of the first connecting wire S 1  or the second connecting wire S 2 , the defects of the first connecting wire S 1  or the second connecting wire S 2  could be repaired. Certainly, the inspecting method can also be applied to the touch panels  400 ,  700 ,  800  and  900  so as to improve the quality of the touch panels  400 ,  700 ,  800  and  900 . 
     In light of above, the inspecting regions in the present invention are disposed on the ends of each sensing line, and the insulation layer exposes the inspecting regions. Therefore, the present invention can directly detect whether there are defects in the sensing lines, and the connecting wires and the sensing lines can be inspected separately. The inspection methods of the touch panel are therefore more efficient. When the defects of the touch panel are detected, they can further be repaired. Accordingly, the touch panel in the present invention can have good quality. 
     Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention.