Patent Publication Number: US-11047903-B2

Title: Display panel and method for testing for occurrence of crack in display panel

Description:
RELATED APPLICATIONS 
     This application is a National Phase of PCT Patent Application No. PCT/CN2019/084504 having International filing date of Apr. 26, 2019, which claims the benefit of priority of Chinese Patent Application No. 201811446731.3 filed on Nov. 29, 2018. The contents of the above applications are all incorporated by reference as if fully set forth herein in their entirety. 
     FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to an electronic device field, and particularly to a display panel and a method for testing for an occurrence of a crack in a display panel. 
     During fabrication of a display panel, an array including multiple display panels is usually fabricated first, and then the multiple display panels are separated by cutting, and a crack is likely to occur in the display panel during the cutting process, leading to failure of the display panel. Therefore, a key step of product quality inspection is whether crack is decided to exist in the display panel after cutting, however, crack is often small and cannot be observed by the naked eye, which greatly increases the difficulty of testing the crack. Therefore, how to realize a display panel and a crack function test and a method for testing for occurrence of a crack in the display panel is an urgent problem. 
     SUMMARY OF THE INVENTION 
     The application provides a display panel and a method for testing for an occurrence of a crack in a display panel to reduce the difficulty of testing for an occurrence of a crack in the display panel. 
     A display panel includes: 
     a panel body, wherein the panel body includes a display region and a non-display region; 
     a ground line, wherein the ground line is disposed in the non-display region, surrounds the display region, and includes a first end and a second end; 
     a first ground connecting portion and a first testing portion, wherein the first ground connecting portion and the first testing portion are parallel electrically connected to the first end; 
     a second ground connecting portion and a second testing portion, wherein the second ground connecting portion and the second testing portion are parallel electrically connected to the second end; and 
     a switch, wherein the switch is electrically connected between the first ground connecting portion and the first end. 
     In the display panel of the present disclosure, the first ground connecting portion includes a first ground connecting lead and a first ground connecting pin, the first ground connecting lead is electrically connected between the switch and the first ground connecting pin, the second ground connecting portion includes a second ground connecting lead and a second ground connecting pin, and the second ground connecting lead is electrically connected between the second end and the second ground connecting pin. 
     In the display panel of the present disclosure, the first testing portion includes a first testing lead and a first testing pin, the first testing lead is electrically connected between the first end and the first testing pin, the second testing portion includes a second testing lead and a second testing pin, and the second testing lead is electrically connected between the second end and the second testing pin. 
     In the display panel of the present disclosure, the switch is a thin film transistor switch, the switch is disposed in the non-display region of the panel body, and the switch and thin film transistors of the panel body are disposed at a same layer. 
     In the display panel of the present disclosure, the non-display region is disposed around the display region, the non-display region includes a bonding region, the bonding region is disposed at one side of the display region, the first ground connecting portion, the first testing portion, the second ground connecting portion, the second testing portion, and the switch are disposed in the bonding region. 
     In the display panel of the present disclosure, the display panel further includes a flexible circuit board, the flexible circuit board is electrically connected to one side of the panel body, and the second ground connecting portion and the second testing portion are disposed at the flexible circuit board. 
     In the display panel of the present disclosure, the display panel further includes a flexible circuit board, the flexible circuit board is electrically connected to one side of the panel body, and the first ground connecting portion, the first testing portion, the second ground connecting portion, the second testing portion, and the switch are disposed at the flexible circuit board. 
     In the display panel of the present disclosure, the first end includes a first electrically connecting pad, the second end includes a second electrically connecting pad, the first ground connecting portion and the first testing portion are electrically connected to the first electrically connecting pad, the second ground connecting portion and the second testing portion are electrically connected to the second electrically connecting pad, and the first electrically connecting pad and the second electrically connecting pad are disposed in the non-display region. 
     A method for testing for an occurrence of a crack in a display panel includes: 
     providing a display panel, wherein the display panel includes: 
     a panel body, wherein the panel body includes a display region and a non-display region; 
     a ground line, wherein the ground line is disposed in the non-display region, surrounds the display region, and includes a first end and a second end; 
     a first ground connecting portion and a first testing portion, wherein the first ground connecting portion and the first testing portion are parallel electrically connected to the first end; 
     a second ground connecting portion and a second testing portion, wherein the second ground connecting portion and the second testing portion are parallel electrically connected to the second end; 
     a switch, wherein the switch is electrically connected between the first ground connecting portion and the first end; 
     inputting a turn-off voltage to the switch to make an open circuit between the first ground connecting portion and the first end; 
     measuring a voltage, a resistance, or a current between the first testing portion and the second testing portion; and 
     determining whether a crack exists or not in the non-display region according to the measured voltage, resistance, or current. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the step of determining whether a crack exists or not in the non-display region according to the measured voltage, resistance, or current includes: 
     when the voltage is zero, an open circuit is decided to exist in the ground line and a crack is decided to exist in the non-display region. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the step of determining whether a crack exists or not in the non-display region according to the measured voltage, resistance, or current includes: 
     when the resistance is infinity, an open circuit is decided to exist in the ground line and a crack is decided to exist in the non-display region. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the step of determining whether a crack exists or not in the non-display region according to the measured voltage, resistance, or current includes: 
     when the current is zero, an open circuit is decided to exist in the ground line and a crack is decided to exist in the non-display region. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the step of determining whether a crack exists or not in the non-display region according to the measured voltage, resistance, or current includes: 
     when the voltage is within a preset voltage range, the ground line is normal and a crack is decided to not exist in the non-display region. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the first ground connecting portion includes a first ground connecting lead and a first ground connecting pin, the first ground connecting lead is electrically connected between the switch and the ground connecting pin, the second ground connecting portion includes a second ground connecting lead and a second ground connecting pin, and the second ground connecting lead is electrically connected between the second end and the second ground connecting pin. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the first testing portion includes a first testing lead and a first testing pin, the first testing lead is electrically connected between the first end and the first testing pin, the second testing portion includes a second testing lead and a second testing pin, and the second testing lead is electrically connected between the second end and the second ground connecting pin. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the switch is a thin film transistor switch, the switch is disposed in the non-display region of the panel body, and the switch and thin film transistors of the panel body are disposed at a same layer. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the non-display region is disposed around the display region, the non-display region includes a bonding region, the bonding region is disposed at one side of the display region, the first ground connecting portion, the first testing portion, the second ground connecting portion, the second testing portion, and the switch are disposed in the bonding region. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the display panel further includes a flexible circuit board, the flexible circuit board is electrically connected to one side of the panel body, and the second ground connecting portion and the second testing portion are disposed at the flexible circuit board. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the display panel further includes a flexible circuit board, the flexible circuit board is electrically connected to one side of the panel body, and the first ground connecting portion, the first testing portion, the second ground connecting portion, the second testing portion, and the switch are disposed at the flexible circuit board. 
     In the method for testing for an occurrence of a crack in a display panel of the present disclosure, the first end includes a first electrically connecting pad, the second end includes a second electrically connecting pad, the first ground connecting portion and the first testing portion are electrically connected to the first electrically connecting pad, the second ground connecting portion and the second testing portion are electrically connected to the second electrically connecting pad, and the first electrically connecting pad and the second electrically connecting pad are disposed in the non-display region. 
     The present disclosure provides a display panel and a method for testing for an occurrence of a crack in a display panel. The display panel includes a panel body, a ground line, a first ground connecting portion, a first testing portion, a second ground connecting portion, a second testing portion and a switch, the panel body includes a display region and a non-display region, the ground line is disposed in the non-display region and surrounds the display region, the ground line includes a first end and a second end, the first ground connecting portion and the first testing portion are parallel connected to the first end, the second ground connecting portion and the second testing portion are parallel connected to the second end, the switch is electrically connected between the first ground connecting portion and the first end, by measuring a voltage, a resistance, or a current between the first testing portion and the second testing portion, when the voltage is zero, the resistance is infinity or the current is zero, an open circuit is decided to exist in the ground line and a crack is decided to exist in the non-display region, thereby the difficulty of testing for an occurrence of a crack in the display panel is reduced. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       In order to more clearly illustrate the embodiments or the technical solutions in prior art, the drawings to be used in the embodiments or prior art description will be briefly described below. Obviously, the drawings in the following description are merely inventions. For some embodiments, other drawings may be obtained from those skilled in the art without any creative work. 
         FIG. 1  is a schematic view of a display panel of a first embodiment according to the present disclosure. 
         FIG. 2  is a schematic view of a display panel of a second embodiment according to the present disclosure. 
         FIG. 3  is a schematic view of a display panel of a third embodiment according to the present disclosure. 
         FIG. 4  is a schematic view of a display panel of a fourth embodiment according to the present disclosure. 
         FIG. 5  is a schematic view of a display panel of a fifth embodiment according to the present disclosure. 
     
    
    
     DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION 
     Referring to  FIG. 1 , the present disclosure provides a display panel  10 . The display panel  10  includes a panel body  11 , a ground line  12 , a first ground connecting portion  13 , a first testing portion  14 , a second ground connecting portion  15 , a second testing portion  16 , and a switch  17 . 
     The panel body  11  includes a display region  11   a  and a non-display region  11   b . The display panel  10  can be a liquid crystal display panel or an organic light emitting diode display panel. 
     The ground line  12  is disposed in the non-display region  11   b . The ground line  12  surrounds the display region  11   a . The ground line  12  includes a first end  121  and a second end  122 . The ground line  12  and a metal layer of the display panel  10  are disposed at a same layer. 
     The first ground connecting portion  13  and the first testing portion  14  are parallel electrically connected to the first end  121 . The first end  121  includes a first electrically connecting pad  1211 . The first ground connecting portion  13  and the first testing portion  14  are electrically connected to the first electrically connecting pad  1211 . The switch  17  is electrically connected between the first ground connecting portion  13  and the first end  121 . 
     The first ground connecting portion  13  includes a first ground connecting lead  131  and a first ground connecting pin  132 . The first ground connecting lead  131  is electrically connected between the switch  17  and the first ground connecting pin  132 . The first testing portion  14  includes a first testing lead  141  and a first testing pin  142 . The first testing lead  141  is electrically connected between the first end  121  and the first testing pin  142 . 
     The second ground connecting portion  15  and the second testing portion  16  are parallel connected to the second end  122 . The second end includes a second electrically connecting pad  1221 . The second ground connecting portion  15  and the second testing portion  16  are electrically connected to the second electrically connecting pad  1221 . 
     The second ground connecting portion  15  includes a second ground connecting lead  151  and a second ground connecting pin  152 . The second ground connecting lead  151  is electrically connected between the second end  122  and the second ground connecting pin  152 . The second testing portion  16  includes a second testing lead  161  and a second testing pin  162 . The second testing lead  161  is electrically connected between the second end  122  and the second testing pin  162 . 
     In one embodiment, the switch  17  is a thin film transistor switch. The switch  17  and thin film transistors of the display panel  10  are disposed at a same layer. 
     The switch  17  can include a switch body  171 , a switch lead  172  and a switch pin  173 . The switch body  171  is electrically connected between the first ground connecting portion  13  and the first end  121 . The switch lead  172  is electrically connected between the switch body  171  and the switch pin  173 , and a control circuit connected to the switch pin  173  inputs an open voltage or a turn-off voltage to the switch  17 . 
     In one embodiment, the non-display region  11   b  surrounds the display region  11   a . The non-display region  11   b  includes a bonding region  11   b   1 . The bonding region  11   b   1  is disposed at one side of the display region  11   a . The first ground connecting portion  13 , the first testing portion  14 , the second ground testing portion  15 , the second testing portion  16 , and the switch  17  are disposed in the bonding region  11   b   1 . The ground line  12 , the first electrically connecting pad  1211 , the second electrically connecting pad  1221 , the switch lead  172 , the first ground lead  131 , the second ground lead  151 , the first testing lead  141 , and the second testing lead  161  and a metal layer of the display panel  10  can be disposed at a same layer. The switch body  171  and thin film transistors of the display panel  10  can be disposed at a same layer. The first ground connecting pin  132 , the second ground connecting pin  152 , the first testing pin  142 , the second testing pin  162 , and the switch pin  173  are disposed at an edge of the display panel  10 . 
     Referring to  FIG. 2 , the present disclosure further provides a display panel  10 . The difference between the display panel  10  shown in the  FIG. 2  and the display panel  10  shown in the  FIG. 1  is the first end  121 , the first electrically connecting pad  1211 , the first ground connecting portion  13 , the first testing portion  14 , and the switch  17  of the display panel  10  shown in the  FIG. 1  are disposed on a left side of the display panel  10 , the first end  121 , the first electrically connecting pad  1211 , the first ground connecting portion  13 , the first testing portion  14 , and the switch  17  of the display panel shown in the  FIG. 1  are disposed on a right side of the display panel  10 . 
     Referring to  FIG. 3 , the present disclosure further provides a display panel  10 . The difference between the display panel  10  shown in the  FIG. 3  and the display panel  10  shown in the  FIG. 1  further includes a flexible circuit board  18 . The flexible circuit board  18  is electrically connected to one side of the display panel  10 . The ground line  12 , the first electrically connecting pad  1211 , the second electrically connecting pad  1221 , one part of the switch lead  172 , one part of the first ground lead  131 , one part of the second ground connecting lead  151 , one part of the first testing lead  141 , and one part of the second testing lead  161  and a metal layer of the display panel  10  are disposed at a same layer, and disposed in the non-display region  11   b  of the display panel  10  to realize a narrow bezel of the display panel  10 . Another part of the switch lead  172 , another part of the first ground connecting lead  131 , another part of the second ground connecting lead  151 , another part of the first ground testing line  141 , another part of the second testing line  161 , the first ground connecting pin  132 , the second ground connecting pin  152 , the first testing pin  142 , the second testing pin  162 , and the switch pin  173  are disposed in the display panel  10 . The first ground connecting pin  132 , the second ground connecting pin  152 , the first testing pin  142 , the second testing pin  162  and the switch pin  173  are disposed at an edge of flexible circuit board  18 . 
     Referring to  FIG. 4 , the present further provides a display panel  10 . The difference between the display panel  10  shown in the  FIG. 4  and the display panel  10  shown in the  FIG. 1  further includes a flexible circuit board  18 . The flexible circuit board  18  is electrically connected to one side of the display panel  10 . The ground line  12 , the first electrically connecting pad  1211 , and the second electrically connecting pad  1221  and a metal layer of the display panel  10  are disposed at a same layer, and are disposed in the non-display region  11   b  of the display panel  10  to realize a narrow bezel of display panel  10 . The switch  17 , the first ground connecting portion  13 , the second ground connecting portion  15 , the first testing portion  14 , and the second testing portion  16  are disposed in the display panel  10 , for example, the switch body  171 , the switch lead  172 , the first ground connecting lead  131 , the second ground connecting lead  151 , the ground testing line  141 , the second testing lead  161 , the first ground connecting pin  132 , the second ground connecting pin  152 , the first testing pin  142 , the second testing pin  162 , and the switch pin  173  are disposed in the display panel  10 . The first ground connecting pin  132 , the second ground connecting pin  152 , the first testing pin  142 , the second testing pin  162 , and the switch pin  173  are disposed at an edge of the flexible circuit board  18 . 
     Referring to  FIG. 5 , the present disclosure further provides display panel  10 . The difference between the display panel  10  shown in the  FIG. 5  and the display panel  10  shown in the  FIG. 1  further includes a flexible circuit board  18 . The flexible circuit board  18  is electrically connected to one side of the display panel  10 . The ground line  12  and a metal layer of the display panel  10  can be disposed at a same layer, and disposed in the non-display region  11   b  of the display panel  10  to realize a narrow bezel of the display panel  10 . The first electrically connecting pad  1211 , the second electrically connecting pad  1221 , the switch  17 , the first ground connecting portion  13 , the second ground connecting portion  15 , the first testing portion  14 , and the second testing portion  16  are disposed in the display panel  10 , for example, the first electrically connecting pad  1211 , the second electrically pad  1221 , the switch body  171 , the switch lead  172 , the first ground connecting lead  131 , the second ground connecting lead  151 , the first testing lead  141 , the second testing lead  161 , the first ground connecting pin  132 , the second ground connecting pin  152 , the first testing pin  142 , the second testing pin  162  and, the switch pin  173  are disposed in the display panel  10 . The first ground connecting pin  132  and the second ground connecting pin  152 , the first testing pin  142 , the second testing pin  162 , and the switch pin  173  are disposed at an edge of the flexible circuit board  18 . 
     The present disclosure further provides a method for testing a crack in the display panel. The display panel  10  has been described as above, and details therefore are not described again. 
     The method for testing a crack in the display panel  10  includes following steps: firstly, a turn-off voltage is inputted to the switch  17  to make an open circuit between the first ground connecting portion  13  and the first end  121  and between the second ground portion  15  and the second end  122 . Then, confirmation can be made if the ground line  12  is broken by measuring a voltage, a resistance, or a current between the first testing portion  14  and the second testing portion  16 . Finally, it can be inferred if a crack occurs on the display panel  10 . 
     If a crack occurs in the display panel  10  during a cutting process, the ground line  12  will be broken. By measuring a voltage, a resistance, or a current between the first testing portion  14  and the second testing portion  16 , it can be confirmed if the ground line  12  is broken. Then, we can infer if a crack occurs on the display panel  10 . 
     When the voltage is measured by a voltmeter, the voltmeter is electrically connected between the first testing pin  142  and the second testing pin  162 . When the measured voltage is zero, an open circuit must occur on the ground line  12 . Therefore, it can be confirmed that a crack occurs on the non-display area  11   b . On the contrary, when the measured voltage is within a predetermined range, the ground line  12  works normally. Therefore, it can be confirmed that a crack does not occur on the non-display region  11   b.    
     When the resistance is measured by a resistance meter, the resistance meter is electrically connected between the first testing pin  142  and the second testing pin  162 . When the measured resistance is infinity, an open circuit must occur on the ground line  12 . Therefore, a crack is confirmed to occur on the non-display area  11   b . When the measured resistance is within a predetermined range, the ground line  12  works normally. Therefore, a crack is confirmed not to occur on the non-display region  11   b.    
     When the current is measured by an ammeter, the ammeter is electrically connected between the first testing pin  142  and the second testing pin  162 . When a current is measured by an ammeter, the ammeter is electrically connected between the first testing pin  142  and the second testing pin. When the measured current is zero, an open circuit must occur on the ground line  12 . Therefore, a crack is confirmed to occur on the non-display area  11   b . On the contrary, when the measured current is within a predetermined range, the ground line  12  works normally. Therefore, it is confirmed that a crack does not occur on the non-display region  11   b.    
     After finishing the test, when the ground line  12  is normal and a crack is decided to not exist in the non-display region  11   b , the control circuit is turned on by the switch pin  173 , the control circuit inputs an open voltage to the switch  17  to electrically connect the first ground connecting portion  13  with the ground line  12 , and to restore the ground line  12  to a ground function. 
     The present disclosure provides a display panel and a method for testing for an occurrence of a crack in a display panel. The display panel includes a panel body, a ground line, a first ground connecting portion, a first testing portion, a second ground connecting portion, a second testing portion and a switch, the panel body includes a display region and a non-display region, the ground line is disposed in the non-display region and surrounds the display region, the ground line includes a first end and a second end, the first ground connecting portion and the first testing portion are parallel connected to the first end, the second ground connecting portion and the second testing portion are parallel connected to the second end, the switch is electrically connected between the first ground connecting portion and the first end, by measuring a voltage, a resistance, or a current between the first testing portion and the second testing portion, when the voltage is zero, the resistance is infinity or the current is zero, an open circuit is decided to exist in the ground line and a crack is decided to exist in the non-display region, thereby the difficulty of testing for an occurrence of a crack in the display panel is reduced. 
     As is understood by persons skilled in the art, the foregoing preferred embodiments of the present disclosure are illustrative rather than limiting of the present disclosure. It is intended that they cover various modifications and that similar arrangements be included in the spirit and scope of the present disclosure, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structures.