Patent Publication Number: US-2020287163-A1

Title: Display substrate and method for manufacturing same, display panel, and display apparatus

Description:
This application is a continuation-in-part of PCT/CN2019/079620, filed on Mar. 26, 2019, which claims priority to Chinese Patent Application No. 201810291817.7, filed Apr. 3, 2018, both of which are fully incorporated by reference herein. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to the field of display technologies, and more particularly to a display substrate, a method for manufacturing same, a display panel and a display apparatus. 
     BACKGROUND 
     Display substrates are products in the technical field of display that are capable of proactively emitting light or passively emitting light. 
     SUMMARY 
     The present disclosure provides a display substrate, method for manufacturing same, display panel and display apparatus. 
     In one aspect, there is provided a display substrate having a display region and a non-display region disposed around the display region, the display substrate includes: 
     a base substrate and a barrier structure disposed on a side of the base substrate, wherein the barrier structure is disposed in the non-display region, and the barrier structure includes a metal structure and a protective layer which are arranged on the substrate in sequence and the protective layer covers the metal structure. 
     Optionally, the metal structure includes at least one closed annular structure, and each of the at least one closed annular structure surrounds the display region. 
     Optionally, the metal structure includes a plurality of closed annular structures ( 021 ) arranged at intervals. 
     Optionally, the plurality of closed annular structures are arranged at equal intervals. 
     Optionally, the non-display region includes a first annular region and a second annular region that respectively surround the display region, and the first annular region is sleeved to a side of the second annular region distal from the display region; and 
     the metal structure is disposed in the first annular region, and a gap exists between the barrier structure and a film layer structure disposed in the second annular region. 
     Optionally, the display substrate further includes a conductive structure disposed in the second annular region; 
     wherein the metal structure and the conductive structure are disposed on the same layer, and a preparation material of the metal structure is as same as that of the conductive structure. 
     Optionally, the conductive structure includes a gate wiring; and 
     the metal structure and the gate wiring are disposed on the same layer, and the preparation material of the metal structure is as same as that of the gate wiring. 
     Optionally, a preparation material of the metal structure includes at least one of molybdenum, titanium, aluminum and silver. 
     Optionally, the display substrate is an organic light emitting diode (OLED) display substrate or a quantum dot light emitting diode (QLED) display substrate. 
     In another aspect, there is provided a method for manufacturing a display substrate, the display substrate having a display region and a non-display region disposed around the display region, the method including: 
     providing a base substrate; and 
     forming a metal structure in the non-display region on the base substrate with a metal material. 
     forming a protective layer in the non-display region on the base substrate having a formed metal structure for causing the protective layer to cover the metal structure. 
     Optionally, forming the metal structure in the non-display region on the base substrate with a metal material includes: 
     forming at least one closed annular structure in the non-display region on the base substrate with the metal material and by a patterning process, wherein each of the at least one closed annular structure surrounds the display region. 
     Optionally, forming at least one closed annular structure in the non-display region on the base substrate with the metal material and by the patterning process includes: 
     forming a plurality of closed annular structures arranged at intervals in the non-display region on the base substrate with the metal material and by the patterning process. 
     Optionally, the non-display region includes a first annular region and a second annular region that respectively surround the display region, and the first annular region is sleeved to a side of the second annular region distal from the display region; and 
     forming the metal structure in the non-display region on the base substrate with a metal material includes: 
     forming the metal structure in the first annular region on the base substrate and forming a conductive structure in the second annular region on the base substrate with the metal material and by a one-patterning process, wherein a gap exists between the barrier structure and the conductive structure. 
     Optionally, forming the metal structure in the first annular region on the base substrate and forming the conductive structure in the second annular region on the base substrate with the metal material and by the one-patterning process includes: 
     forming the metal structure in the first annular region on the base substrate and forming a gate wiring in the second annular region on the base substrate with the metal material and by the one-patterning process, wherein a gap exists between the metal structure and the gate wiring. 
     Optionally, forming the metal structure in the non-display region on the base substrate with the metal material includes: 
     forming the metal structure in the non-display region on the base substrate with at least one of molybdenum, titanium, aluminum and silver and by the patterning process. 
     Optionally, a width of the at least one closed annular structure ranges from 5 μm to 15 μm, and a height of the at least one closed annular structure in a direction vertical to the base substrate ranges from 10 μm to 20 μm. 
     Optionally, a preparation material of the protective layer comprises polyimide. 
     Optionally, the non-display region includes a first annular region and a second annular region that respectively surround the display region, the first annular region is sleeved to a side of the second annular region distal from the display region, the metal structure is disposed in the first annular region, and a gap exists between the metal structure and a film layer structure disposed in the second annular region; 
     the display substrate further includes a conductive structure disposed in the second annular region, the metal structure and the conductive structure are disposed on the same layer, and a preparation material of the metal structure is as same as that of the conductive structure; 
     a preparation material of the metal structure includes at least one of molybdenum, titanium, aluminum and silver; 
     a preparation material of the protective layer includes polyimide. 
     In a further aspect, there is provided a display panel including the display substrate, the display substrate has a display region and a non-display region disposed around the display region, and 
     the display substrate includes a base substrate and a barrier structure disposed on a side of the base substrate; and wherein the barrier structure is disposed in the non-display region, the barrier structure includes a metal structure and a protective layer which are arranged on the substrate in sequence and the protective layer covers the metal structure. 
     In a further another aspect, there is provided a display apparatus, including the display panel as defined in the further aspect. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic structural view of a display substrate according to an embodiment of the present disclosure; 
         FIG. 2  is a top view of a display substrate according to an embodiment of the present disclosure; 
         FIG. 3  is a top view of another display substrate according to an embodiment of the present disclosure; 
         FIG. 4  is a schematic structural view of another display substrate according to an embodiment of the present disclosure; 
         FIG. 5  is a flowchart of a method for manufacturing a display substrate according to an embodiment of the present disclosure; 
         FIG. 6  is a flowchart of another method for manufacturing a display substrate according to an embodiment of the present disclosure; 
         FIG. 7  is a schematic view showing that a gate insulation layer is formed according to an embodiment of the present disclosure; 
         FIG. 8  is a schematic view showing that a metal film layer is formed according to an embodiment of the present disclosure; 
         FIG. 9  is a schematic view showing that a photoresist is formed according to an embodiment of the present disclosure; 
         FIG. 10  is a schematic view showing that the photoresist is exposed according to an embodiment of the present disclosure; 
         FIG. 11  is a schematic view showing that the photoresist is developed according to an embodiment of the present disclosure; 
         FIG. 12  is a schematic view showing that the photoresist is etched according to an embodiment of the present disclosure; and 
         FIG. 13  is a schematic view showing that a metal structure is formed after stripping of the photoresist according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure will be further described in detail with reference to the accompanying drawings, to present the objects, technical solutions, and advantages of the present disclosure more clearly. 
     An organic light emitting diode (OLED) display substrate is a flexible display substrate capable of proactively emitting light. The related art provides an OLED display substrate and an edge of the OLED display substrate is provided with a crack dam. The crack dam is configured to block a crack from extending to the inside of a display region of the OLED display substrate when the crack appears at the edge of the OLED display substrate. In the current OLED display substrate, the crack dam is generally an inorganic dielectric layer formed with silicon oxide, silicon nitride or the like. 
     However, since a film layer made of silicon oxide or silicon nitride has a poor anti-impact capability. When the edge of the OLED display substrate is subjected to external collisions or is twisted, a crack is apt to appear at the crack dam on the edge. If the crack extends to the inside of a display region of the OLED display substrate, package of the OLED display substrate may fail. In this case, moisture or oxygen and the like in the air may enter the inside of the OLED display substrate through the crack, and the internal organic light emitting material is caused to lose efficacy. As such, growing black spots (GDS) may occur on the OLED display substrate, such that quality of the display substrate is affected. 
       FIG. 1  is a schematic structural view of a display substrate according to an embodiment of the present disclosure. As illustrated in  FIG. 1 , the display substrate has a display region A and a non-display region B disposed around the display region A. The display substrate includes a substrate  01  and a barrier structure disposed on a side of the substrate  01 . The barrier structure  02  may also be referred to as a crack dam. 
     Referring to  FIG. 1 , the barrier structure  02  is disposed in the non-display region B. The barrier structure  02  includes a metal structure  02   a  and a protective layer  02   b  which are arranged on the substrate  01  in sequence. The protective layer  02   b  covers the metal structure  02   a.    
     Optionally, the display substrate according to this embodiment of the present disclosure may be a flexible display substrate. A base substrate in the display substrate may be made of a flexible material. Optionally, the display substrate may be an OLED display substrate or a quantum dot light emitting diode (QLED) display substrate. 
     In summary, in the display substrate according to the embodiment of the present disclosure, the barrier structure disposed in the non-display region includes a metal structure made of a metal material and the metal structure is covered by a protective layer. When the edge of the display substrate is subjected to external impacts or is twisted, since the metal material has a high hardness, a good ductility and a strong anti-impact capability and the protective layer may have a certain buffer function, the metal structure is not apt to generate cracks, and thus the internal structure of the display substrate may be effectively protected, and a risk that GDS occurs may be decreased. 
     Optionally, the metal structure may be made of at least one of molybdenum (MO), titanium (Ti), aluminum (Al) and silver (Ag). That is, the preparation material of the metal structure includes at least one of molybdenum, titanium, aluminum and silver. Since the molybdenum has a high melting point which may reach 2620° C., the molybdenum has a good chemical stability, the hardness and the anti-impact capability of the metal molybdenum are also high, the metal structure in the barrier structure made of the molybdenum may ensure all of the structural stability, the hardness and the anti-impact capability of the barrier structure, and thus the internal structure of the display substrate may be effectively protected. Optionally, the preparation material of the metal structure may also include silicon (Si) and the specific preparation material of the metal structure is not limited in the embodiments of the present application. 
     Optionally, the protective layer may be made of organic materials. For example, the preparation material of the protective layer may include polyimide (PI). 
     Optionally, the metal structure includes at least one closed annular structure. That is, the metal structure includes one or a plurality of closed annular structures. Each closed annular structure surrounds the display region. 
     Exemplarily,  FIG. 2  is a top view of a display substrate according to an embodiment of the present disclosure. As illustrated in  FIG. 2 , the metal structure  02   a  includes a closed annular structure  021   a . Further exemplarily,  FIG. 3  is a top view of another display substrate according to an embodiment of the present disclosure. As illustrated in  FIG. 3 , the metal structure  02   a  includes a plurality of closed annular structures  021   a  arranged at intervals. For example, as illustrated in  FIG. 3 , the metal structure  02   a  includes three closed annular structures  021   a  arranged at intervals. 
     Optionally, a center of the closed annular structure may coincide with a center of the display region. Exemplarily, in the display substrate as illustrated in  FIG. 3 , the plurality of closed annular structures may share a common center point. That is, the center points of the plurality of closed annular structures may the same. The same point is the center point of the display region. 
     Optionally, when the metal structure includes a plurality of closed annular structures arranged at intervals, the plurality of closed annular structures may be arranged at equal intervals. That is, a spacing between any two adjacent closed annular structures is the same. 
     Optionally, a width of the closed annular structure ranges from 5 μm to 15 μm, and a height of the closed annular structure in a direction vertical to the base substrate ranges from 10 μm to 20 μm. 
     Optionally, referring to  FIG. 1 , the non-display region B includes a first annular region B 1  and a second annular region B 2  that respectively surround the display region A. The first annular region B 1  is sleeved to a side of the second annular region B 2  distal from the display region A. That is, the second annular region B 2  is disposed between the display region A and the first annular region B 1 , and the display region A is disposed in a region enclosed by the second annular region B 2 . The display region A and the second annular region B 2  may form a package region of the display substrate together. 
     Referring to  FIG. 1 , the barrier structure  02  is disposed in the first annular region B 1 , and a gap exists between the barrier structure  02  and a film layer structure  03  disposed in the second annular region B 2 . 
     It should be noted that since the gap exists between the barrier structure disposed in the first annular region and the film layer structure disposed in the second annular region, when the edge of the display substrate is subjected to external collisions or is twisted and thus the barrier structure generates the crack, the crack on the barrier structure cannot extend to the film layer structure disposed in the second annular region. That is, the crack on the barrier structure may not affect the structure in the package region of the display substrate. Therefore, package failures of the display substrate may be prevented, the GDS may be prevented from the display substrate, and the yield and quality of the display substrate are improved. 
     Optionally, the display substrate further includes a conductive structure disposed in the second annular region. That is, the film layer structure in the second annular region may include the conductive structure. The metal structure and conductive structure may be disposed in the same layer but arranged at intervals. The material of the barrier structure is the same as that of the conductive structure. That is, both the metal structure and the conductive structure may be made of the same metal material. 
     It should be noted that since the metal structure and the conductive structure are disposed in the same layer, the conductive structure and the metal structure that is disposed in the same layer but arranged at intervals with the conductive structure may be formed by a one-patterning process, and thus the manufacture cost and the complexity of the manufacture process of the display substrate may not be increased. 
     Optionally, the conductive structure disposed in the second annular region includes a gate wiring, and the metal structure and the gate wiring may be disposed in the same layer but arranged at intervals. The gate wiring is generally manufactured in the same layer with a gate in the display region. That is, the metal structure and the gate may be disposed in the same layer. 
     Optionally, the conductive structure disposed in the second annular region may also include a source and drain metal wiring or the other metal wiring layers, and the metal structure may be disposed in the same layer with any metal wiring layer in the conductive structure, which is not limited in the embodiment of the present disclosure. 
     Optionally,  FIG. 4  is a schematic structural view of another display substrate according to an embodiment of the present disclosure.  FIG. 4  only illustrates the film layer structure in the non-display region of the display substrate. As illustrated in  FIG. 4 , the second annular region B 2  of the display substrate includes: a first insulation layer M 1 , a second insulation layer M 2 , a first metal wiring layer  04 , a third insulation layer M 3 , a second metal wiring layer  05 , a fourth insulation layer M 4 , a flexible material layer  06  and a package layer  07  that are disposed in sequence on the base substrate  01 . The first metal wiring layer may be the gate wiring, and may be disposed in the same layer with the gate in the display region. The second metal wiring layer may be the source and drain wiring, and may be disposed in the same layer with the source and the drain in the display region. The first annular region B 1  of the display substrate includes a barrier structure  02 . The metal structure  02   a  in the barrier structure  02  and the first metal wiring layer  04  or the second metal wiring layer  05  may be disposed in the same layer. That is, the metal structure  02   a  and the first metal wiring layer  04  may be manufactured by a one-patterning process. Alternatively, the metal structure  02   a  and the second metal wiring layer  05  may be manufactured by a one-patterning process. 
     Optionally, in the display substrate as illustrated in  FIG. 4 , the first insulation layer may be an integral layer structure, or may be only disposed in the second annular region; and the second insulation layer may be an integral layer structure, or may be only disposed in the second annular region, which are not limited in the embodiment of the present disclosure. 
     In summary, in the display substrate according to the embodiment of the present disclosure, the barrier structure disposed in the non-display region includes a metal structure made of a metal material and the metal structure is covered by a protective layer. When the edge of the display substrate is subjected to external impacts or is twisted, since the metal material has a high hardness, a good ductility and a strong anti-impact capability and the protective layer may have a certain buffer function, the metal structure is not apt to generate cracks, and thus the internal structure of the display substrate may be effectively protected and a risk that GDS occurs may be decreased. In addition, since the gap exists between the barrier structure disposed in the first annular region and the film layer structure disposed in the second annular region, when the edge of the display substrate is subjected to external collisions or is twisted and thus the barrier structure generates the crack, the crack on the barrier structure cannot extend to the film layer structure disposed in the second annular region. That is, the crack on the barrier structure may not affect the structure in the package region of the display substrate. Therefore, package failures of the display substrate may be prevented, the GDS may be prevented from the display substrate, and the yield and quality of the display substrate are improved. 
       FIG. 5  is a flowchart of a method for manufacturing a display substrate according to an embodiment of the present disclosure. The display substrate has a display region and a non-display region disposed around the display region. As illustrated in  FIG. 5 , the method may include the processes: 
     In step  501 , a base substrate is provided. 
     In the embodiment of the present disclosure, the base substrate is used as a carrier for manufacturing a film layer structure. Optionally, the base substrate may be a flexible base substrate. For example, the base substrate may be manufactured with a PI material. 
     In step  502 , a metal structure in the non-display region is formed on the base substrate with a metal material. 
     Optionally, the non-display region of the display substrate includes a first annular region and a second annular region that respectively surround the display region, and the first annular region is sleeved to a side of the second annular region distal from the display region. The metal structure is disposed in the first annular region, and a gap exists between the metal structure and a film layer structure disposed in the second annular region. In addition, the metal structure in the first annular region may be formed with a conductive structure in the second annular region (or the display region) by a one-patterning process. 
     In step  503 , a protective layer is formed in the non-display region on the base substrate having a formed metal structure so that the protective layer covers the metal structure. 
     In the embodiments of the present disclosure, a structure formed by the metal structure and the protective layer covering the metal structure is called as a barrier structure. 
     In summary, in the method for manufacturing a display substrate according to the embodiment of the present disclosure, the metal structure is formed in the non-display region of the display substrate with the metal material. When the edge of the display substrate is subjected to external impacts or is twisted, since the metal material has a high hardness, a good ductility and a strong anti-impact capability and the protective layer covering the metal structure may have a certain buffer function, and thus the barrier structure is not apt to generate cracks, the internal structure of the display substrate may be effectively protected, and a risk that GDS occurs may be decreased. 
     Optionally, step  502  specifically includes: at least one closed annular structure is formed in the non-display region on the base substrate with the metal material and by a patterning process, and each of the at least one closed annular structure surrounds the display region. Optionally, a plurality of closed annular structures arranged at intervals may be formed in the non-display region of the base substrate with the metal material and by the patterning process. 
     In the embodiment of the present disclosure, the non-display region may include the first annular region and the second annular region that respectively surround the display region, and the first annular region is disposed on the side of the second annular region distal from the display region. The implement process of the step  502  may include: the metal structure is formed in the first annular region on the base substrate and a conductive structure is formed in the second annular region on the base substrate with the metal material and by a one-patterning process, and a gap exists between the metal structure and the conductive structure. 
     Optionally, the conductive structure includes a gate wiring, and thus the metal structure may be formed in the first annular region on the base substrate and the gate wiring may be formed in the second annular region on the base substrate with the metal material and by a one-patterning process, and a gap exists between the metal structure and the gate wiring. 
     It should be noted that forming the conductive structure and the metal structure in the barrier structure on the base substrate by the one-patterning process can prevent the manufacture cost and the complexity of the manufacture process from been increased, effectively protect the display substrate and improve the yield of the display substrate. 
     Optionally, the metal material may be at least one of molybdenum, titanium, aluminum and silver. The implement process of the step  502  may include: the metal structure is formed in the non-display region on the base substrate with at least one of molybdenum, titanium, aluminum and silver and by the patterning process. Optionally, the metal structure may be formed in the non-display region of the base substrate with molybdenum and by patterning process. Since the metal material of molybdenum has a high hardness and a strong anti-impact capability, the metal structure in the barrier structure made of the molybdenum can ensure all the structural stability, the hardness and the anti-impact capability of the barrier structure so as to realize an effective protection for the internal structure of the display substrate. 
       FIG. 6  is a flowchart of another method for manufacturing a display substrate according to an embodiment of the present disclosure. It takes that the conductive structure is a gate wiring as an example, that is, it takes that the conductive structure and the gate wiring as well as the gate are formed by a one-patterning process as an example to describe the process of manufacturing a display substrate. As illustrated in  FIG. 6 , the method may include the following working processes: 
     In step  601 , a base substrate is provided. 
     In the embodiment of the present disclosure, the base substrate is used as a carrier for manufacturing a film layer structure. Optionally, the base substrate may be a flexible base substrate. For example, the base substrate may be manufactured with a PI material. 
     In step  602 , a gate insulation layer is formed on the base substrate. 
     Optionally, a first insulation layer M 1  may be deposited on the base substrate  01  by a physical vapor deposition (PVD) process, wherein the first insulation layer M 1  may be the gate insulation layer.  FIG. 7  illustrates that the base substrate  01  is deposited with the gate insulation layer M 1 . 
     In step  603 , the base substrate which has a formed the gate insulation layer is cleaned. 
     Optionally, after the gate insulation layer is formed, the display substrate may be cleaned with a hydrofluoric (HF) acid solution to improve an interface morphology of the display substrate. 
     In step  604 , a metal film layer is formed on the base substrate which has a formed gate insulation layer. 
     In the embodiment of the present disclosure, a metal film layer S may be continuously deposited on a side of the gate insulation layer M 1  away from the base substrate  01 . For example, the metal film layer S may be deposited by magnetron sputtering. The metal film layer S may be made of molybdenum. The molybdenum has a high hardness, a good chemical stability and a strong anti-impact capability.  FIG. 8  illustrates the base substrate  01  has a formed metal film layer S. 
     In step  605 , a photoresist is coated on the metal film layer. 
     Optionally, the photoresist may be a photosensitive resin material.  FIG. 9  illustrates the base substrate  01  is coated with a photoresist J. 
     In step  606 , the base substrate which is coated with the photoresist is exposed and developed. 
     In the embodiment of the present disclosure, the base substrate  01  may be exposed with ultraviolet light via a mask plate Y. Exemplarily,  FIG. 10  is a schematic view showing that the photoresist is exposed according to an embodiment of the present disclosure. The base substrate  01  may be exposed by the mask plate Y as illustrated in  FIG. 10 .  FIG. 10  only illustrates a partial exposure pattern for forming the metal structure in the mask plate Y. When the metal structure is a closed annular structure, the exposure pattern in the mask plate Y for forming the metal structure is also a closed annular structure. Afterwards, the exposed base substrate  01  may be placed into a developing solution for development.  FIG. 11  is a schematic view showing that the photoresist is developed according to an embodiment of the present disclosure. 
     In step  607 , the metal film layer is etched, the photoresist is stripped and a gate metal pattern and the metal structure are formed. 
     The gate metal pattern includes the gate in the display region and the gate wiring in the non-display region (the second annular region). 
     Exemplarily,  FIG. 12  is a schematic view showing that the photoresist is etched according to an embodiment of the present disclosure. The part in the metal film layer  04  that is not covered by the photoresist may be etched, and the structure of the etched display substrate may be illustrated in  FIG. 12 . Further, the photoresist J may be stripped such that the gate metal pattern (not illustrated in the drawing) and the metal structure are obtained.  FIG. 13  is a schematic view showing a partial structure of a display substrate according to an embodiment of the present disclosure.  FIG. 13  illustrates a part of a metal structure  02   a  disposed in the non-display region of the display substrate. The metal structure  02   a  may be in an annular shape. 
     In the embodiment of the present disclosure, by the one-patterning process (which is also referred to as a backplane process, BP) in step  601  to step  607 , the gate metal pattern and the metal structure  02   a  are formed, such that the manufacture cost and the complexity of the manufacture process of the display substrate may not be increased, and the metal structure  02   a  may effectively protect the display substrate. 
     In step  608 , the protective layer is formed in the non-display region of the base substrate so that the protective layer covers the metal structure. 
     Optionally, the protective layer covering the metal structure may be formed with PI and by the patterning process. 
     It should be noted that in the method for manufacturing a display substrate according to the embodiment of the present disclosure, the sequence of the steps may be adaptively adjusted, and the steps may also be reduced or increased according to the actual needs. A person skilled in the art would readily envisage method variations without departing from the technical scope disclosed in the present disclosure, and these method variations shall all fall within the protection scope of the present disclosure, which are thus not described herein any further. 
     In summary, in the method for manufacturing a display substrate according to the embodiment of the present disclosure, the metal structure is formed in the non-display region of the display substrate with the metal material. When the edge of the display substrate is subjected external impacts or is twisted, since the metal material has a high hardness, a good ductility and a strong anti-impact capability and the protective layer covering the metal structure may have a certain buffer function, and thus the barrier structure is not apt to generate cracks, the internal structure of the display substrate may be effectively protected, and the risk that GDS occurs may be decreased. In addition, since the gap exists between the barrier structure disposed in the first annular region and the film layer structure disposed in the second annular region, when the edge of the display substrate is subjected to external collisions or is twisted and thus the barrier structure generates the crack, the crack on the barrier structure cannot extend to the film layer structure disposed in the second annular region. That is, the crack on the barrier structure may not affect the structure in the package region of the display substrate. Therefore, package failures of the display substrate may be prevented, the GDS may be prevented from the display substrate, and the yield and quality of the display substrate are improved. 
     An embodiment of the present disclosure provides a display panel. The display panel may include the display substrate as illustrated in any one of  FIGS. 1 to 4 . The display panel may be: a liquid crystal panel, an electronic paper, an OLED panel, an active matrix OLED (AMOLED) panel, a QLED panel, a mobile phone, a tablet computer, a television, a display, a laptop computer, a digital photo frame, a navigator or other product or part having a display function. The AMOLED panel may be a flexible display panel. 
     An embodiment of the present disclosure provides a display apparatus. The display apparatus includes the above described display panel. 
     The foregoing descriptions are merely optional embodiments of the present disclosure, and are not intended to limit the present disclosure. Within the spirit and principles of the disclosure, any modifications, equivalent substitutions, improvements, etc., are within the protection scope of the present disclosure.