Patent Publication Number: US-2022221752-A1

Title: Display panel and display device

Description:
This application is a division of U.S. patent application Ser. No. 16/314,863 filed Jan. 3, 2019, which is hereby incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to a field of display technology, and in particular to a display panel and a display device. 
     BACKGROUND 
     The description herein provides only background information related to this application, but does not necessarily constitute the existing technology. 
     A display apparatus has advantages, such as having a thin body, saving-power, low radiation, and is widely used. A conventional display apparatus mostly is a backlight display apparatus, which comprises a liquid crystal display (LCD) panel and a backlight module. Operating principle of the display apparatus is that liquid crystal (LC) molecules are disposed between two substrates, where the two substrates are parallelly disposed, and a driver voltage applies on the two substrates to control rotation direction of the LC molecules, so that light of a backlight module are refracted to generate images. 
     Technology development of a thin film transistor-liquid crystal display (TFT-LCD) is relatively mature in the prior art, and the TFT-LCD has economic benefits advantages. For surrounding metal wiring of the TFT-LCD, a double-layer metal wiring design is adopted to reduce resistance and prevent distortion caused by signal transmission delay. 
     With an advent of narrow bezels, a distance between the double-layer metal wiring disposed on the TFT-LCD to provide a common voltage and an edge of the glass substrate is also reducing. That is to say, the distance between the metal wiring and the edge of the glass substrate is reduced. Because of a limited accuracy of cutting machines, exterior gases are easily getting into an effective display area along with a corroded gap of the TFT-LCD after cut, and finally cause the TFT-LCD to display abnormality. 
     SUMMARY 
     The present disclosure provides a display panel and a display device to prevent a generation of bubbles in a display area, thereby effectively improving a display quality. 
     To achieve the above object, the present disclosure provides a display panel comprising a display area and an outer peripheral area. The display panel comprises: 
     a first substrate, a second substrate disposed opposite to the first substrate, and a liquid crystal layer sandwiched between the first substrate and the second substrate. The outer peripheral area of the first substrate comprises a glass substrate. A first metal layer is formed on the glass substrate. An insulating layer is formed on the first metal layer. A second metal layer is formed on the insulating layer. A passivation protective layer is formed on the second metal layer. The glass substrate comprises a cutting edge, and a distance between the second metal layer and the cutting edge of the glass substrate is greater than a distance between the first metal layer and the cutting edge of the glass substrate. 
     To achieve the above object, the present disclosure provides a display panel comprising a display area and an outer peripheral area. The display panel comprises: 
     a first substrate, a second substrate disposed opposite to the first substrate, and a liquid crystal layer sandwiched between the first substrate and the second substrate. The outer peripheral area of the first substrate comprises a glass substrate. A first metal layer is formed on the glass substrate. An insulating layer is formed on the first metal layer. A second metal layer is formed on the insulating layer. A passivation protective layer is formed on the second metal layer. The glass substrate comprises a cutting edge. The first metal layer comprises a first side close to the cutting edge of the glass substrate and the second metal layer comprises a second side close to the cutting edge of the glass substrate. A distance between the second side of the second metal layer and the cutting edge of the glass substrate is 1.5 microns to 2.5 microns longer than a distance of the first side of the first metal layer and the cutting edge of the glass substrate. The second side of the second metal layer and a side of the insulating layer close to the cutting edge of the glass substrate is stepped. A angle formed between a side edge of the second side of the second metal layer close to the cutting edge of the glass substrate and a bottom edge of the second metal layer ranges from 20-80 degrees. A thickness of the second metal layer is 0.5 microns. 
     Another object of the present disclosure is to provides a display device. The display device comprise a control component and the display panel above. 
     For surrounding metal wiring of the TFT-LCD, a double-layer metal wiring design is adopted to reduce a resistance and prevent a distortion caused by signal transmission delay. With an advent of a narrow bezel, a distance between the double-layer metal wiring to provide a common voltage and an edge of the glass substrate is also reduced. That is to say, the distance between the metal wiring and the edge of the glass substrate is reduced. Because of a limited accuracy of cutting machines, the cutting edge of the glass substrate is likely to be close to or very approach to a metal edge, which causes the passivation protective layer configured to protect the second metal layer to lift or fall off, thus, causing contaminants such as moisture to corrode an upper metal. Further, exterior gases are easily getting into an effective display area along with a corroded gap of the display panel, and finally resulting in display abnormality of the display panel. A distance between the second metal layer and the cutting edge of the glass substrate is greater than a distance between the first metal layer and the cutting edge of the glass substrate. After cutting, a distance between the metal wiring and the cutting edge of the glass substrate is increased, and an area of the passivation protective layer covering the second metal layer and the insulating layer is larger, which protects the metal well, and prevent the second metal layer from being corroded, thus, effectively preventing a generation of bubbles in the display area and effectively improving a display quality. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The drawings are included to provide a further understanding of embodiments of the present disclosure, which form portions of the specification and are used to illustrate implementation manners of the present disclosure and are intended to illustrate operating principles of the present disclosure together with the description. Apparently, the drawings in the following description are merely some of the embodiments of the present disclosure, and those skilled in the art are able to obtain other drawings according to the drawings without contributing any inventive labor. In the drawing: 
         FIG. 1  is a schematic diagram of a display device according to an embodiment of the present disclosure; 
         FIG. 2  is a schematic diagram of a cross-sectional view of an ideal narrow bezel (a cross-sectional view along CC′ in  FIG. 1 ) of an embodiment of the present disclosure; 
         FIG. 3  is a schematic diagram of a second cross-sectional view of a risk narrow bezel (a cross-sectional view along CC′ in  FIG. 1 ) according to an embodiment of the present disclosure; 
         FIG. 4  is a schematic diagram of a third cross-sectional view of a risk narrow bezel (a cross-sectional view along CC′ in  FIG. 1 ) according to an embodiment of the present disclosure; 
         FIG. 5  is a schematic diagram showing a design of a glass substrate double-layer metal wiring according to an embodiment of the present disclosure; 
         FIG. 6  is a schematic diagram of a first convex block of an embodiment of the present disclosure; 
         FIG. 7  is a schematic diagram of a second convex block of an embodiment of the present disclosure; 
         FIG. 8  is a schematic diagram of a first groove of an embodiment of the present disclosure; 
         FIG. 9  is a schematic diagram of a first bulge of an embodiment of the present disclosure; and 
         FIG. 10  is a schematic diagram of a second groove and a second bulge of an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Specific structure and function details disclosed herein are only representative and are used for the purpose of describing exemplary embodiments of the present disclosure. However, the present disclosure may be achieved in many alternative forms and shall not be interpreted to be only limited to the embodiments described herein. 
     It should be understood in the description of the present disclosure that terms such as “central”, “horizontal”, “upper”, “lower”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, etc. indicate direction or position relationships shown based on the drawings, and are only intended to facilitate the description of the present disclosure and the simplification of the description rather than to indicate or imply that the indicated device or element must have a specific direction or constructed and operated in a specific direction, and therefore, shall not be understood as a limitation to the present disclosure. In addition, the terms such as “first” and “second” are only used for the purpose of description, rather than being understood to indicate or imply relative importance or hint the number of indicated technical features. Thus, the feature limited by “first” and “second” can explicitly or impliedly comprise one or more features. In the description of the present disclosure, the meaning of “a plurality of” is two or more unless otherwise specified. In addition, the term “comprise” and any variant are intended to cover non-exclusive inclusion. It should be noted in the description of the present disclosure that, unless otherwise regulated and defined, terms such as “installation,” “bonded,” and “bonding” shall be understood in broad sense, and for example, may refer to fixed bonding or detachable bonding or integral bonding; may refer to mechanical bonding or electrical bonding; and may refer to direct bonding or indirect bonding through an intermediate medium or inner communication of two elements. For those of ordinary skill in the art, the meanings of the above terms in the present disclosure may be understood according to concrete conditions. The terms used herein are intended to merely describe concrete embodiments, not to limit the exemplary embodiments. Unless otherwise noted clearly in the context, singular forms “one” and “single” used herein are also intended to comprise plurals. It should also be understood that the terms “comprise” and/or “include” used herein specify the existence of stated features, integers, steps, operation, units and/or assemblies, not excluding the existence or addition of one or more other features, integers, steps, operation, units, assemblies and/or combinations of these. 
     In the drawings, structurally similar elements are denoted by the same reference numerals. 
     An exemplary method is as follows: 
     A narrow bezel design is a trend of a development of thin film transistor-liquid crystal display (TFT-LCD). The narrow bezel is the pursuit of the market. A technology development of the TFT-LCD is relatively mature in the prior art, and the TFT-LCD has an advantage of economic benefits. For surrounding metal wiring of the TFT-LCD, a double-layer metal wiring design is adopted to reduce a resistance and prevent a distortion caused by signal transmission delay. 
     With an advent of the narrow bezel and a glass substrate double-layer metal wiring design, in one aspect, a distance between a double-layer metal wiring disposed on a side of a TFT-LCD metal wiring array substrate to provide a common voltage and an edge of the glass substrate is also reducing. That is to say, the distance between the metal wiring and an cutting edge  111  of the glass substrate is reduced. Thus, contaminants such as moisture corrodes an upper metal from edges. Further, exterior gases are easily getting into an effective display area along with a corroded gap, and finally resulting in display abnormality of the TFT-LCD. On the other hand, because of a development and etching precision of the second metal layer  14 , the relative position of the second metal layer  14  changes with the first metal layer  12 . As shown in  FIG. 3  and  FIG. 4 , an edge of the second metal layer  14  in  FIG. 3  is aligned with an edge of a lower insulating layer  13 , and a passivation protective layer  15  disposed at the edge of second metal layer  14  becomes thinner and thinner, resulting in the second metal layer  14  being easily corroded. A worst case is shown in  FIG. 4 , the edge of the second metal layer  14  is beyond the edge of the first metal layer  12 , and a bottom surface of the second metal layer  14  forming the slope is not protected by the passivation protective layer  15 , thus, the second metal layer  14  is most easily to be corroded. 
     To achieve the above object, the present disclosure provides a display panel  2  comprising a display area and an outer peripheral area. The display panel comprises: 
     a first substrate  10 , a second substrate  20  disposed opposite to the first substrate  10 , and a liquid crystal layer sandwiched between the first substrate  10  and the second substrate  20 . The outer peripheral area of the first substrate  10  comprises a glass substrate  11 . A first metal layer  12  is formed on the glass substrate  11 . An insulating layer  13  is formed on the first metal layer  12 . A second metal layer  14  is formed on the insulating layer  13 . A passivation protective layer  15  is formed on the second metal layer  14 . The glass substrate  11  comprises a cutting edge  111 , and a distance between the second metal layer  14  and the cutting edge  111  of the glass substrate  11  is greater than a distance between the first metal layer  12  and the cutting edge  111  of the glass substrate  11 . 
     For surrounding metal wiring of the glass substrate  11 , the double-layer metal wiring design is adopted to reduce the resistance and prevent the distortion caused by signal transmission delay. With the advent of the narrow bezel, the distance between the double-layer metal wiring to provide a common voltage and an edge of the glass substrate is also reduced. That is to say, the distance between the metal wiring and the cutting edge  111  of the glass substrate  11  is reduced. Because of a limited accuracy of cutting machines, the cutting edge  111  of the glass substrate  11  is likely to be close to or very approach to a metal edge, which causes the passivation protective layer  15  configured to protect the second metal layer  14  to lift or fall off, thus, causing contaminants such as moisture to corrode an upper metal. Further, exterior gases are easily getting into an effective display area along with the corroded gap, and finally resulting in the display abnormality of the display panel  2 . A distance between the second metal layer  14  and the cutting edge  111  of the glass substrate  11  is greater than a distance between the first metal layer  12  and the cutting edge  111  of the glass substrate  11 . After cutting, a distance between the metal wiring and the cutting edge  111  of the glass substrate  11  is increased, and an area of the passivation protective layer  15  covering the second metal layer  14  and the insulating layer  13  is larger, which protects the metal well, and prevent the second metal layer  14  from being corroded, thus, effectively preventing a generation of bubbles in the display area and effectively improving a display quality. 
     In an alternative embodiment, the first metal layer  12  comprises a first side  121  close to the cutting edge  111  of the glass substrate  11 . The second metal layer  14  comprises a second side  141  close to the cutting edge  111  of the glass substrate  11 . A distance between the second side  141  of the second metal layer  14  and the cutting edge  111  of the glass substrate  11  is 1.5 microns to 2.5 microns longer than a distance of the first side  121  of the first metal layer  12  and the cutting edge  111  of the glass substrate  11 . 
     When the distance between the second side  141  of the second metal layer  14  and the cutting edge  111  of the glass substrate  11  is less than 1.5 microns longer than the distance of the first side  121  of the first metal layer  12  and the cutting edge  111  of the glass substrate  11 . When cutting, since the limited accuracy of cutting machines, the cutting edge  111  of the glass substrate  11  is likely to be close to or very approach to the metal edge, which causes the passivation protective layer  15  configured to protect the second metal layer  14  to lift or fall off, thus, causing contaminants such as moisture to corrode the upper metal. Further, exterior gases are easily getting into an effective display area along with the corroded gap, and finally resulting in the display abnormality of the display panel  2 . When the distance between the second side  141  of the second metal layer  14  and the cutting edge  111  of the glass substrate  11  is more than 2.5 microns longer than the distance of the first side  121  of the first metal layer  12  and the cutting edge  111  of the glass substrate  11 , a narrow bezel requirement of an ideal narrow bezel may not be realized, and a lot of glass material is wasted, resulting in an increase in production costs. When the distance between the second side  141  of the second metal layer  14  and the cutting edge  111  of the glass substrate  11  is 1.5 microns to 2.5 microns longer than the distance of the first side  121  of the first metal layer  12  and the cutting edge  111  of the glass substrate  11 , the cutting edge  111  of the glass substrate  11  does not close to or very approach to the metal edge, which prevents the passivation protective layer  15  configured to protect the second metal layer  14  from lifting or falling off. Thus, the passivation protective layer  15  can well protect the second metal layer  14  when it does not lift or fall off, and contaminants such as moisture does not corrode the second metal layer  14 , preventing the exterior gases from getting into an effective display area along with the corroded gap such that the display abnormality would not happened in the display panel  2 . Moreover, a best utilization rate of the glass material is obtained, which saves material and cost. 
     In an alternative embodiment, a side of the second metal layer  14  close to the cutting edge  111  of the glass substrate  11  and a side of the insulating layer  13  close to the cutting edge  111  of the glass substrate  11  is stepped. 
     Because the edge of the second metal layer  14  is closer to the cutting edge relative to an edge of the insulating layer  13 , both of a side edge of the insulating layer  13  forming on the second metal layer  14  and a side edge of the insulating layer  13  covering the second metal layer  14  are closer to the cutting edge  111  of the glass substrate  11  than a side edge of the second metal layer  14 , of which formed two steps to ensure to ensure the thickness of the passivation protective layer  15  at the edge of the second metal layer  14 . Thus, the thickness of the passivation protective layer  15  is ensured, and a adhesion of the passivation protective layer  15  is relatively good, and the passivation protective layer  15  after cutting does not easily lift or fall off, which protect the second metal layer  14  better. 
     In an alternative embodiment, a angle formed between a side edge of the second metal layer  14  close to the cutting edge  111  of the glass substrate  11  and a bottom edge of the second metal layer  14  ranges from 20-80 degrees. 
     The angle formed between the side edge of the second metal layer  14  close to the cutting edge  111  of the glass substrate  11  and the bottom edge of the second metal layer  14  ranges from 20-80 degrees. If the angel is less than 20 degrees, considering effects of exposure, development, and etching precision, the thickness of the passivation protective layer  15  at the edge of the second metal layer  14  is not ensured, and the passivation protective layer  15  is relatively thin, resulting that the second metal layer  14  is easily corrode and the exterior gases are easily getting into the effective display area along with the corroded gap, and finally resulting in the display abnormality of the display panel  2 . If the angle is more than 80 degrees, a adhesion between the motivation protective layer  15  and the second metal layer  14  is relatively poor, which make the motivation protective layer  15  easily to lift, and makes the contaminants such as moisture to corrode the upper metal. Thus, the exterior gases is easily getting into the effective display area along with the corroded gap, and finally resulting in the display abnormality in the display panel  2 . When the angle is in a range of 20-80 degrees, the thickness of the motivation protective layer  15  is ensured, and the adhesion between the motivation protective layer  15  and the second metal layer  14  is ensured, which prevent the passivation protective layer  15  from lifting or falling off, prevent the second metal layer  14  from being corroded, and ensure the display effect. 
     In an alternative embodiment, a thickness of the second metal layer  14  is 0.3-0.7 microns. 
     The thickness of the second metal layer  14  is 0.5 microns, and the thickness of the second metal layer  14  is not thin relative to other layers, which ensures a performance of the second metal layer  14  on the circuit. The thickness of the second metal layer  14  is not thick relative to other layers. If it is too thick, it may affect an electrical conductivity of the second metal layer  14  and it may lead to an exposure of a gate electrode when the edge of the second metal layer  14  comes into contact with the passivation protective layer  15 , and further, the protection function of the passivation protective layer  15  is gone. Mainly according to that a width precision d1 of the first metal layer  12  and the second metal layer  14  is about ±1 um, a thickness precision d2 of the second metal layer  14  is about 0.5 um, the angle of the second metal layer  14  is 20-80°, and d3=d2*tan(a). Taking d1, d2, and d3 into account, a shrinkage width of the second metal layer  14  is 1.5 to 2.5 um, which ensure the second metal layer  14  to form a step with two lower layers, ensure the thickness of the passivation protective layer  15  formed on the edge of the second metal layer  14 , and prevent the second metal layer  14  from being corroded. 
     As another embodiment of the present disclosure,  FIG. 6  is a schematic view of a first convex block  122  of an embodiment of the present disclosure, which is an expansion based on  FIG. 1  to  FIG. 5 . It can be known from an conjunction of  FIG. 1  to  FIG. 5 : 
     In an alternative embodiment, a first convex block  122  is disposed on the glass substrate  11 . The first convex block  122  is disposed between the first side  121  of the first metal layer  12  and the cutting edge. The first convex block  122  and the first metal layer  12  are formed by a same process. A height of the first convex block  122  is no more than a thickness of the first metal layer  12 . The first convex block  122  is insulated from a circuit disposed on the first substrate  10 . 
     The first convex block  122  and the first metal layer  12  are formed by a same process. The first convex block  122  and the first metal layer  12  are formed by a same mask process. No additional process steps is needed, and no additional material is required. The first convex block  122  is disposed between the first side  121  of the first metal layer  12  and the cutting edge, and a height of the first convex block  122  is no more than a thickness of the first metal layer  12 , which effectively prevent the passivation protective layer  15  from lifting, and increase a production efficiency of the display panel  2  at the same time. Moreover, the first convex block  122  is insulated from a circuit disposed on the first substrate  10 . The cutting edge  111  of the glass substrate  11  is close to the first convex block  122 , and the passivation protective layer  15  covers the first convex block  122 . The first convex block  122  has a large contact area with the passivation protective layer  15 , and has high adhesion, preventing the passivation protective layer  15  from lifting, thus preventing contamination such as moisture from corroding the second metal layer  14  and ensuring the display effect. 
     As another embodiment of the present disclosure,  FIG. 7  is a schematic view of a second convex block  142  of an embodiment of the present disclosure, which is an expansion based on  FIG. 1  to  FIG. 5 . It can be known from an conjunction of  FIG. 1  to  FIG. 5 : 
     In an alternative embodiment, a second convex block  142  is disposed on the insulating layer  13 . The second convex block  142  is disposed between the first side  121  of the first metal layer  12  and the second side  141  of the second metal layer  14 . The second convex block  142  and the second metal layer  14  are formed by a same process. A height of the second convex block  142  is no more than a thickness of the second metal layer  14 . The second convex block  142  is insulated from a circuit disposed on the first substrate  10 . 
     The second convex block  142  is disposed between the first side  121  of the first metal layer  12  and the second side  141  of the second metal layer  14 . The second convex block  142  and the second metal layer  14  are formed by a same process. And the second convex block  142  is insulated from a circuit disposed on the first substrate  10 . The cutting edge  111  of the glass substrate  11  is close to the second convex block  142 , and the passivation protective layer  15  covers the second convex block  142 . The second convex block  142  has a large contact area with the passivation protective layer  15 , and has high adhesion, preventing the passivation protective layer  15  from lifting, thus preventing contamination such as moisture from corroding the second metal layer  14 . 
     As another embodiment of the present disclosure,  FIG. 8  is a schematic view of a first groove  132  of an embodiment of the present disclosure, which is an expansion based on  FIG. 1  to  FIG. 5 . It can be known from an conjunction of  FIG. 1  to  FIG. 5 : 
     In an alternative embodiment, a first groove  132  is disposed on the insulating layer  13 . The first groove  132  is disposed between the second side  141  of the second metal layer  14  and the cutting edge. The first groove  132  is recessed from the insulating layer  13  to the glass substrate  11 . The first groove  132  and the insulation layer  13  are formed by a same process. 
     Because of the limited accuracy of cutting machines, the cutting edge  111  of the glass substrate  11  is likely to be close to or very approach to the metal edge, which causes the passivation protective layer  15  to lift or fall off. Thus, the first groove  132  is disposed on the insulating layer  13  to increase a contact area of the passivation protective layer  15  and the insulating layer  13 , and the passivation protective layer  15  is not easily to lift or fall off, which prevent the contamination such as moisture from corroding the second metal layer  14 . 
     As another embodiment of the present disclosure,  FIG. 9  is a schematic view of a first bulge  131  of an embodiment of the present disclosure, which is an expansion based on  FIG. 1  to  FIG. 5 . It can be known from an conjunction of  FIG. 1  to  FIG. 5 : 
     In an alternative embodiment, the first bulge  131  is arranged on the insulating layer  13 . The first bulge  131  is disposed between the second side  141  of the second metal layer  14  and the cutting edge. The first bulge  131  is raised from a direction form the insulating layer  13  to the second metal layer  14 . The first bulge  131  and the insulating layer  13  are formed by a same process. 
     Because of the limited accuracy of cutting machines, the cutting edge  111  of the glass substrate  11  is likely to be close to or very approach to the metal edge, which causes the passivation protective layer  15  to lift or fall off. Thus, the convex structure is disposed on the insulating layer  13  to increase the contact area of the passivation protective layer  15  and the insulating layer  13 , and the passivation protective layer  15  is not easily to lift or fall off after cutting, which prevent the contamination such as moisture from corroding the second metal layer  14 . 
     In an alternative embodiment, a height of the first bulge  131  relative to the insulating layer  13  is no more than the thickness of the second metal layer  14 . 
     Because of the limited accuracy of cutting machines, the cutting edge  111  of the glass substrate  11  is likely to be close to or very approach to the metal edge, which causes the passivation protective layer  15  to lift or fall off. Thus, the convex structure is disposed on the insulating layer  13  to increase the contact area of the passivation protective layer  15  and the insulating layer  13 , the adhesion is good, and the passivation protective layer  15  is not easily to lift or fall off after cutting. In addition, when a vacuum alignment is formed, the first bulge  131  prevents a height of the passivation protective layer  15  herein from being higher than other areas, this preventing the convex structure herein from being stressed so much, preventing the convex structure herein from being easily damaged, and preventing the protection function of the passivation protective layer  15  to the second metal layer  14  from being lost. 
     In an alternative embodiment, a second groove  134  and a second bulge  133  are disposed on the insulating layer  13 . The second groove  134  and the second bulge  133  are disposed between the second side  141  of the second metal layer  14  and the cutting edge. 
     Because of the limited accuracy of cutting machines, the cutting edge  111  of the glass substrate  11  is likely to be close to or very approach to the metal edge, which causes the passivation protective layer  15  to lift or fall off. Thus, the convex structure and the groove is disposed on the insulating layer  13  to increase the contact area of the passivation protective layer  15  and the insulating layer  13 , and the passivation protective layer  15  is not easily to lift or fall off after cutting, which prevent the contamination such as moisture from corroding the upper metal layers. 
     To achieve the above object, the present disclosure provides a display panel  2  comprising a display area and an outer peripheral area. The display panel comprises: 
     a first substrate  10 , a second substrate  20  disposed opposite to the first substrate  10 , and a liquid crystal layer sandwiched between the first substrate  10  and the second substrate  20 . The outer peripheral area of the first substrate  10  comprises a glass substrate  11 . A first metal layer  12  is formed on the glass substrate  11 . An insulating layer  13  is formed on the first metal layer  12 . A second metal layer  14  is formed on the insulating layer  13 . A passivation protective layer  15  is formed on the second metal layer  14 . The glass substrate  11  comprises a cutting edge  111  of the glass substrate  11 . The first metal layer  12  comprises a first side  121  close to the cutting edge  111  of the glass substrate  11 . The second metal layer  14  comprises a second side  141  close to the cutting edge  111  of the glass substrate  11 . A distance between the second side  141  of the second metal layer  14  and the cutting edge  111  of the glass substrate  11  is 1.5 microns to 2.5 microns longer than a distance of the first side  121  of the first metal layer  12  and the cutting edge  111  of the glass substrate  11 . The second side  141  of the second metal layer  14  and a side of the insulating layer  13  close to the cutting edge  111  of the glass substrate  11  is stepped. A\angle formed between the second side  141  of the second metal layer  14  and a bottom edge of the second metal layer  14  ranges from 20-80 degrees. The thickness of the second metal layer  14  is 0.5 microns. 
     For surrounding metal wiring of the glass substrate  11 , the double-layer metal wiring design is adopted to reduce the resistance and prevent the distortion caused by signal transmission delay. With the advent of the narrow bezel, the distance between the double-layer metal wiring to provide a common voltage and an edge of the glass substrate is also reduced. That is to say, the distance between the metal wiring and the cutting edge  111  of the glass substrate  11  is reduced. Because of a limited accuracy of cutting machines, the cutting edge  111  of the glass substrate  11  is likely to be close to or very approach to a metal edge, which causes the passivation protective layer  15  configured to protect the second metal layer  14  to lift or fall off, thus, causing contaminants such as moisture to corrode an upper metal. Further, exterior gases are easily getting into an effective display area along with the corroded gap, and finally resulting in the display abnormality of the display panel  2 . Mainly according to that a width precision d1 of the first metal layer  12  is about ±1 um, a thickness precision d2 of the second metal layer  14  is about 0.5 um, the angle of the second metal layer  14  is 20-80°, and d3=d2*tan(a). Taking d1, d2, and d3 into account, a shrinkage width of the second metal layer  14  is 1.5 to 2.5 um. That is to say, the distance between the second side  141  of the second metal layer  14  and the cutting edge  111  of the glass substrate  11  is 1.5 microns to 2.5 microns longer than the distance of the first side  121  of the first metal layer  12  and the cutting edge  111  of the glass substrate  11 , which ensure the second metal layer  14  to form a step with two lower layers, ensure the thickness of the passivation protective layer  15  formed on the edge of the second metal layer  14 , and prevent the second metal layer  14  from being corroded. The distance between the second metal layer  14  and the cutting edge  111  of the glass substrate  11  is greater than the distance between the first metal layer  12  and the cutting edge  111  of the glass substrate  11 . After cutting, the distance between the metal wiring and the cutting edge  111  of the glass substrate  11  is increased, and the area of the passivation protective layer  15  covering the second metal layer  14  and the insulating layer  13  is larger, which protects the metal well, and prevent the second metal layer  14  from being corroded, thus effectively preventing the generation of bubbles in the display area and effectively improving the display quality. 
     Another object of the present disclosure is to provide a display device  1 . The display device comprises a control component  3  and the display panel  2  described above. 
     A panel of the present disclosure is selected from a twisted nematic (TN) panel, an in-plane switching (IPS) panel, and a vertica alignment (VA) panel. Of course, other types of panels are used as long as they are applicable 
     The above content is a further detailed description of the present disclosure in conjunction with the specific preferred embodiments, and the specific implementation of the present disclosure is not limited to the description. It will be apparent to those skilled in the art that a number of simple deductions or substitutions may be made without departing from the conception of the present disclosure, which should be considered as being within the scope of the present disclosure