Patent Publication Number: US-2023134347-A1

Title: Display panel and display device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to Chinese Patent Application No. 202211086332.7, filed on Sep. 6, 2022, the content of which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure relates to the field of display technologies, and in particular, to a display panel and a display device. 
     BACKGROUND 
     For current display panels to achieve a full-screen design, a light-transmission hole is provided at a position in a display region corresponding to a camera arranging position. Since some signal lines may be disconnected by the light-transmission hole provided in the display area, how to ensure a normal driving of sub-pixels arranged corresponding to the light-transmission hole has become the focus of the researchers. 
     SUMMARY 
     In view of this, various embodiments of the present disclosure provide a display panel including a light-transmission hole and a display device including the display panel. 
     In one aspect, some embodiments of the present disclosure provide a display panel. The display panel may include a display region; a first non-display region at least partially surrounding the display region; a first light-transmission hole, the first light-transmission hole including a first light-transmission sub-hole and a second light-transmission sub-hole arranged along a first direction, and the display region at least partially surrounding the first light-transmission hole, and a second non-display region located between the first light-transmission sub-hole and the second light-transmission sub-hole. The display panel may also include signal lines arranged in the display region, the signal lines being arranged along the first direction and each extending along a second direction, and connection lines, each of the connection lines electrically connecting two segments of a respective one of the signal lines located at two sides of the first light-transmission hole. The connection lines may include first-type connection lines and second-type connection lines, each of the first-type connection lines has at least one part located between the first light-transmission sub-hole and the second light-transmission sub-hole, and each of the second-type connection lines has at least one part located between the first light-transmission sub-hole and the first non-display region. A distance between two adjacent first-type connection lines of the first-type connection lines may be smaller than a distance between two adjacent second-type connection lines of the second-type connection lines. 
     In another aspect, some embodiments of the present disclosure provide a display device including the display panel described above. 
     The display panel and display device provided by embodiments of the present disclosure each include the first-type connection lines and the second-type connection lines. Two segments of the first signal line that are disconnected by the first light-transmission hole are connected by the first-type connection line or the second-type connection line, so that a signal transmission path is conductive/connected. 
     Furthermore, in embodiments of the present disclosure, the first-type connection line is arranged in the region between the first light-transmission sub-hole and the second light-transmission sub-hole, and the region between the first light-transmission sub-hole and the second light-transmission sub-hole is the second non-display region that is not used for image displaying, so the second non-display region is utilized more reasonably. 
     Furthermore, one side of the first light-transmission sub-hole close to the second light-transmission sub-hole and one side of the second light-transmission sub-hole close to the first light-transmission sub-hole are provided with a larger number of connection lines for electrically connecting the first signal line that is disconnected by the first light-transmission sub-hole, the second light-transmission sub-hole, or the second non-display region. In embodiments of the present disclosure, the distance between two adjacent first-type connection lines is smaller than the distance between two adjacent second-type connection lines. As a result, the mutual interference between the first-type connection lines located between the first light-transmission sub-hole and the second light-transmission sub-hole is reduced, which is beneficial to reducing the signal crosstalk between the first-type connection lines located between the first light-transmission sub-hole and the second light-transmission sub-hole. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       In order to better illustrate technical solutions in the embodiments of the present disclosure, the accompanying drawings used in the embodiments are briefly introduced as follows. It should be noted that the drawings described as follows are merely part of the embodiments of the present disclosure, and other drawings can also be acquired by those skilled in the art. 
         FIG.  1    is a schematic diagram of a display panel according to some embodiments of the present disclosure; 
         FIG.  2    is a schematic diagram of another display panel according to some embodiments of the present disclosure; 
         FIG.  3    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  4    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  5    is a schematic cross-sectional view taken along BB′ shown in  FIG.  4   ; 
         FIG.  6    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  7    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  8    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  9    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  10    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  11    is a partially enlarged view of a display panel according to some embodiments of the present disclosure; 
         FIG.  12    is a cross-sectional view of a dummy pixel and a sub-pixel according to some embodiments of the present disclosure; 
         FIG.  13    is a partially enlarged view of a first non-display region of a display panel according to some embodiments of the present disclosure; 
         FIG.  14    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  15    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  16    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; 
         FIG.  17    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure; and 
         FIG.  18    is a schematic diagram of a display device according to some embodiments of the present disclosure. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     For better illustrating technical solutions of the present disclosure, embodiments of the present disclosure will be described in detail as follows with reference to the accompanying drawings. 
     It should be noted that the described embodiments are merely exemplary embodiments of the present disclosure, which shall not be interpreted as providing limitations to the present disclosure. All other embodiments obtained by those skilled in the art without creative efforts according to the embodiments of the present disclosure are within the scope of the present disclosure. 
     The terms used in the embodiments of the present disclosure are merely for the purpose of describing particular embodiments but not intended to limit the present disclosure. Unless otherwise noted in the context, the singular form expressions “a”, “an”, “the” and “said” used in the embodiments and appended claims of the present disclosure are also intended to represent plural form expressions thereof. 
     It should be understood that the term “and/or” used herein is merely an association relationship describing associated objects, indicating that there can be three relationships, for example, A and/or B can indicate that three cases, i.e., A alone, A and B, B alone. In addition, the character “/” herein generally indicates that the related objects before and after the character are in an “or” relationship. 
     It should be understood that although the layer can be described using the terms of “first”, “second”, etc., in the embodiments of the present disclosure, the layer will not be limited to these terms. These terms are merely used to distinguish light-transmission holes from one another. For example, without departing from the scope of the embodiments of the present disclosure, a first light-transmission hole can also be referred to as a second light-transmission hole, similarly, a second light-transmission hole can also be referred to as a first light-transmission hole. 
     Some embodiments of the present disclosure provide a display panel.  FIG.  1    is a schematic diagram of a display panel according to some embodiments of the present disclosure. As shown in  FIG.  1   , the display panel has a display region AA, a first non-display region NA 1 , and a first light-transmission hole H 1 . The display panel includes sub-pixels (not shown) located in the display region AA. Exemplarily, the sub-pixel includes a pixel driving circuit and a light-emitting element that are electrically to each other. The light-emitting element includes at least one of an organic light-emitting diode, a micro light-emitting diode, or a quantum dot light-emitting diode. 
     As shown in  FIG.  1   , the first light-transmission hole H 1  includes a first light-transmission sub-hole H 11  and a second light-transmission sub-hole H 12  arranged in a first direction x. The display region AA at least partially surrounds the first light-transmission hole H 1 . The first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  may be fused or arranged optical components, such as a camera. In some embodiments of the present disclosure, the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  may be blind holes that do not run though the display panel in a thickness direction of the display panel or may be through-holes that run though the display panel in the thickness direction of the display panel. In some embodiments of the present disclosure, the shape of the first light-transmission sub-hole H 11  and the shape of the second light-transmission sub-hole H 12  may be the same. In some embodiments of the present disclosure, the shape of the first light-transmission sub-hole H 11  and the shape of the second light-transmission sub-hole H 12  may be different. In some embodiments of the present disclosure, the area of the first light-transmission sub-hole H 11  and the area of the second light-transmission sub-hole H 12  may be the same. In some embodiments of the present disclosure, the area of the first light-transmission sub-hole H 11  and the area of the second light-transmission sub-hole H 12  may be different. The present disclosure does not limit thereto. 
     Exemplarily, as shown in  FIG.  1   , the display panel further has a second non-display area NA 2 . Along the first direction x, the second non-display area NA 2  is located between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 . That is, in embodiments of the present disclosure, no sub-pixel is arranged in the region of the first light-transmission sub-hole H 11 , the region of the second light-transmission sub-hole H 12 , and the region between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  along the first direction x. 
     As shown in  FIG.  1   , the display panel further includes signal lines  1  that are located in the display region and arranged along the first direction x. The signal lines  1  each extend along the second direction y. Each of the signal lines  1  is electrically connected to multiple pixel driving circuits that are arranged along the second direction y, so as to drive the multiple light-emitting elements. 
     Exemplarily, the signal lines  1  at least includes a first signal line  11 , and the first signal line  11  has two segments located at two sides of the first light-transmission hole H 1  along the second direction y. That is, a virtual extension line of the first signal line  11  passes the first light-transmission hole H 1 . 
     As shown in  FIG.  1   , the display panel further includes: at least two first-type connection lines  21  and at least two second-type connection lines  22 . The first-type connection line  21  electrically connects two segments of one first signal line  11  that are located at two sides of the first light-transmission hole H 1 . The second-type connection line  22  electrically connects two segments of another one first signal line  11  that are located at two sides of the first light-transmission hole H 1 . As shown in  FIG.  1   , the first-type connection line  21  has at least one part located between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 , and the second-type connection line  22  has at least one part located between the first light-transmission sub-hole H 11  and the first non-display region NA 1 . 
     In some embodiments of the present disclosure, as shown in  FIG.  1   , among at least a part of the least two first-type connection lines  21 , a distance d 1  between two adjacent first-type connection lines  21  is smaller than a distance d 2  between two adjacent second-type connection lines  22 . 
     The display panel of embodiments of the present disclosure is provided with the first-type connection line  21  and the second-type connection line  22 , the first signal line  11  is disconnected by the first light-transmission hole H 1 , and two segments of the first signal line  11  located at two sides of the first light-transmission hole H 1  are electrically connected by the first-type connection line  21  or the second-type connection line  22 , so that a signal transmission path is conductive/connected. 
     Furthermore, the first-type connection line  21  is arranged in the region between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 , and the region between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  is the second non-display region NA 2  that is not used for image displaying, so the second non-display region NA 2  is utilized more reasonably. 
     Furthermore, one side of the first light-transmission sub-hole H 11  close to the second light-transmission sub-hole H 12  and one side of the second light-transmission sub-hole H 12  close to the first light-transmission sub-hole H 11  are provided with a larger number of connection lines for electrically connecting the first signal line  11  that is disconnected by the first light-transmission sub-hole H 11 , the second light-transmission sub-hole H 12 , or the second non-display region NA 2 . In embodiments of the present disclosure, the distance d 1  between two adjacent first-type connection lines  21  is smaller than the distance d 2  between two adjacent second-type connection lines  22 . As a result, the mutual interference between the first-type connection lines  21  located between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  is reduced, which is beneficial to reducing the signal crosstalk between the first-type connection lines  21  located between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 . 
     Exemplarily, as shown in  FIG.  1   , the at least two first-type connection lines  21  include at least one first A connection line  211 , and each of the at least one first A connection line  211  has at least one part located in the display region AA. With such a configuration, the driving of the pixel driving circuits that are located in a same column and located at two sides of the first light-transmission hole H 1  is realized, and the number of the connection lines arranged at a periphery of the first light-transmission sub-hole H 11  or the second light-transmission sub-hole H 12  is reduced, thereby being beneficial to reducing a width of a non-display region surrounding the first light-transmission sub-hole H 11  or the second light-transmission sub-hole H 12 .  FIG.  1    illustrates an example in which five first A connection lines  211  are arranged between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 , and each of the five first A connection lines  211  has a part in the display region AA. 
       FIG.  2    is a schematic diagram of another display panel according to some embodiments of the present disclosure. In some exemplary embodiment, as shown in  FIG.  2   , the display panel further has a third non-display region NA 3  and a fourth non-display region NA 4 . The display region AA at least partially surrounds the third non-display region NA 3  and the fourth non-display region NA 4 . The third non-display region NA 3  at least partially surrounds the first light-transmission sub-hole H 11 , and the fourth non-display region NA 4  at least partially surrounds the second light-transmission sub-hole H 12 . 
     As shown in  FIG.  2   , the at least two first-type connection lines  21  further include at least one first B connection line  212 , and the at least one first B connection line  212  is located in the third non-display region NA 3  or the fourth non-display region NA 4 . That means, the first B connection line  212  is arranged at least partially surrounding the first light-transmission sub-hole H 11 , or the first B connection line  212  is arranged at least partially surrounding the second light-transmission sub-hole H 12 .  FIG.  2    illustrates an example in which each of the third non-display region NA 3  and the fourth non-display region NA 4  is provided with one first B connection line  212  therein. Exemplarily, the first B connection line  212  has at least one part that extends along an edge of the first light-transmission sub-hole H 11  or extends along an edge of the second light-transmission sub-hole H 12 . In the example shown in  FIG.  2   , one first B connection line  212  partially surrounds the first light-transmission sub-hole H 11 , and another one first B connection line partially surrounds the second light-transmission sub-hole H 12 . With such a configuration, at an aspect, the space of the second non-display region NA 2  between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  can be effectively utilized, thereby avoiding that the first-type connection line  21  occupies other space in the display panel; and at another aspect, a length of the first B connection line  212  does not need to be too large, thereby ensuring that the load of the first signal line  1  connected to the first B connection line  212  is consistent with the load of other signal line  1  that does not pass the first light-transmission hole H 1 . 
     Exemplarily, as shown in  FIG.  1   , the at least two second-type connection lines  22  include at least one second A connection line  221 , and each of the at least one second A connection line  221  has at least one part located in the display region AA. With such a configuration, the driving of the pixel driving circuits that are located in a same column and located at two sides of the first light-transmission hole H 1  is realized, and the number of the connection lines arranged at a periphery of the first light-transmission hole H 1  is reduced, thereby being beneficial to reducing a width of a non-display region surrounding the first light-transmission hole H 1  and thus improving the visual effect.  FIG.  1    illustrates an example in which three second A connection lines  221  are arranged between the first light-transmission sub-hole H 11  and the first non-display region NA 1 , and the three second A connection lines  221  are all located in the display region AA. 
     Exemplarily, as shown in  FIG.  2   , the at least two second-type connection lines  22  include at least one second B connection line  222 , and the at least one second B connection line  222  is located in the third non-display region NA 3 . That is, the second B connection line  222  partially surrounds the first light-transmission sub-hole H 11 . With such a configuration, a length of the second-type connection line  22  does not need to be too large, thereby ensuring that the load of the first signal line  1  connected to the second-type connection line  22  is consistent with the load of other signal line  1  that does not pass the first light-transmission hole H 1 . 
     In some exemplary embodiments, as shown in  FIG.  2   , the display panel includes first-type connection lines  21 , one or more of the first-type connection lines  21  are configured as the first A connection lines  211 , and another one or more of the first-type connection lines  21  are configured as the first B connection lines  212 . That is, one or more of the first-type connection lines  21  each have at least one part located in the display region AA, and another one or more of the first-type connection lines  21  each at least partially surround the first light-transmission sub-hole H 11  or the second light-transmission sub-hole H 12 . Similarly, in some embodiments, the display panel includes second-type connection lines  22 , one or more of the second-type connection lines  22  are configured as the second A connection lines  221 , and another one or more of the second-type connection lines  22  are configured as the second B connection lines  222 . That is, one or more of the second-type connection lines  22  each have at least one part located in the display region AA, and another one or more of the second-type connection lines  22  each at least partially surround the first light-transmission sub-hole H 11 . 
       FIG.  3    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure. In some exemplary embodiments of the present disclosure, the number of the first-type connection lines  21  is less than the number of the second-type connection lines  22 . With such a configuration, the light transmittance of the region between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  is increased. In the display device including the display panel, optical elements can be arranged in the region between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 , thereby enriching the functions of the display panel and improving the user experience. 
       FIG.  4    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure. Exemplarily, as shown in  FIG.  4   , the first-type connection lines  21  include at least two first A connection lines  211  and at least two first B connection lines  212 . The first A connection line  211  includes at least one part located in the display region AA. The first B connection line  212  at least partially surrounds the first light-transmission sub-hole H 11 . In some embodiments, at least one first-type connection line  21  has at least one part surrounds the second light-transmission sub-hole H 12 . In some embodiments of the present disclosure, a distance d 11  of two adjacent first A connection lines  211  is greater than or equal to a distance d 12  of two adjacent first B connection lines  212 . With such a configuration, the space for arranging the first B connection lines  212  is reduced, thereby avoiding that a width of the non-display region surrounding the first light-transmission sub-hole H 11  or the second light-transmission sub-hole H 12  is too large. 
       FIG.  5    is a schematic cross-sectional view taken along BB′ shown in  FIG.  4   . In some embodiments in which the first-type connection lines  21  includes at least two first B connection lines  212 , as shown in  FIG.  5   , two adjacent first B connection lines  212  are located in different layers. Such an arrangement can further reduce a distance between two adjacent first B connection lines  212 , which is beneficial to narrowing the width of the space occupied by the at least two first B connection lines  212 . Accordingly, more first-type connection lines  21  can be arranged in the limited region between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 . In some embodiments, in a direction perpendicular to a plane of the display panel, at least one first B connection line  212  overlaps at least one first A connection line  211 . 
       FIG.  6    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure. Exemplarily, as shown in  FIG.  6   , the display region AA has a symmetry axis Z extending along the second direction y, and the symmetry axis Z passes the first light-transmission hole H 1 . In an exemplary embodiment, the symmetry axis Z overlaps the first light-transmission sub-hole H 11  or the symmetry axis Z overlaps the second light-transmission sub-hole H 12 . In an example as shown in  FIG.  6   , the symmetry axis Z overlaps the second light-transmission sub-hole H 12 . With such a configuration, the region that is surrounded by the display region AA and does not display images is arranged at a position close to a central axis of the display panel, thereby improving the symmetry of the display region AA, and thus improving the overall display effect in a visual aspect. 
     Exemplarily, as shown in  FIG.  1   ,  FIG.  2   ,  FIG.  3    and  FIG.  4   , along the first direction x, a distance d 3  between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  is not equal to a distance d 4  between the first light-transmission sub-hole H 11  and the first non-display region NAL 
     In some embodiments, d 3  is greater than d 4 , so that more first-type connection lines  21  may be arranged between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 . As a result, less second-type connection lines  22  are arranged between the first light-transmission sub-hole H 11  and the first non-display region NA 1 , and the crosstalk between the second-type connection lines  22  and other wires in the display region AA is reduced. 
       FIG.  7    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure. In an embodiment, as shown in  FIG.  7   , d 3  is smaller than d 4 , so that the light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  may be arranged in a more compact manner, which is beneficial to improving the visual effect of the display panel. 
       FIG.  8    and  FIG.  9    are schematic diagrams of yet another two display panels according to some embodiments of the present disclosure. In some exemplary embodiments of the present disclosure, as shown in  FIG.  8    and  FIG.  9   , the display panel further includes a second light-transmission hole H 2 . Along the first direction x, the second light-transmission hole H 2  is located at a side of the second light-transmission sub-hole H 12  away from the first light-transmission sub-hole H 11 . Exemplarily, along the first direction x, a length of the second light-transmission hole H 2  may be smaller than that of the first light-transmission hole H 1 . 
     As shown in  FIG.  8    and  FIG.  9   , the display panel further includes at least one third-type connection line  23 . The third-type connection line  23  has at least one part located between the first light-transmission hole H 1  and the second light-transmission hole H 2 . In some embodiments of the present disclosure, the third-type connection line  23  may be configured to connect two segments of the first signal line  11  that are located at two sides of the first light-transmission hole H 1 . Alternatively, the signal lines  1  further include at least one second signal line  12 . Along the second direction y, each second signal line  12  has two segments that are located at two sides of the second light-transmission hole H 2 . In some embodiments, one or more of the at least one third-type connection line  23  may be configured to connect the two segments of the second signal line  12 . 
     Exemplarily, as shown in  FIG.  8   , the distance d 3  between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  is greater than a distance d 5  between the second light-transmission sub-hole H 12  and the second light-transmission hole H 2 . In some embodiments of the present disclosure, an optical element such as a camera may be arranged between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 . When designing the distance between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  and the distance between the second light-transmission sub-hole H 12  and the second light-transmission hole H 2 , the distance between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  is larger in some embodiments of the present disclosure, so that more optical elements may be arranged between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12 , thereby being beneficial to improving the non-display performance of the display panel, such as photographing. 
     Exemplarily, the region between the first light-transmission hole H 1  and the second light-transmission hole H 2  belongs to the display region AA and is provided with sub-pixels (not shown). 
     Exemplarily, as shown in  FIG.  8    and  FIG.  9   , the third-type connection lines  23  include at least one third A connection line  231 . The third A connection line  231  has at least one part located in the display region AA. The third A connection line  231  is configured to connect two segments of the first signal line  11  that are located at two sides of the first light-transmission hole H 1 ; or the third A connection line  231  is configured to connect two segments of the second signal line  12  that are located at two sides of the second light-transmission hole H 2 . Such arrangement can reduce the number of the connection lines arranged at a periphery of the first light-transmission hole H 1  or at a periphery of the second light-transmission hole H 2 , thereby being beneficial to reducing the width of the non-display region surrounding the first light-transmission hole H 1  or the second light-transmission hole H 12 . 
     In some embodiments, as shown in  FIG.  8   , the third-type connection lines  23  include at least one third B connection line  232 , and the at least one third B connection line  232  is located in the fifth non-display region NA 5 . The fifth non-display region NA 5  at least partially surrounds the second light-transmission hole H 2 . Exemplarily, the third-type connection line  23  has at least one part that may extend along an edge of the second light-transmission hole H 2 . Such arrangement can avoid that a length of the third B connection line  232  is too large and ensure that the load of the signal line  1  connected to the third B connection line  232  is consistent with the load of other signal line  1  that does not pass the first light-transmission hole H 1  or the second light-transmission hole H 2 . 
     Exemplarily, as shown in  FIG.  8   , the width of the fifth non-display region NA 5  is greater than that of the third non-display region NA 3  or that of the fourth non-display region NA 4 . Accordingly, in some embodiments, an aperture diameter of the second light-transmission hole H 2  is smaller than an aperture diameter of the third non-display region NA 3  or an aperture diameter of the fourth non-display region NA 4 . With such a configuration, more third B connection lines  232  may be arranged in the fifth non-display region NA 5 , thereby being beneficial to reducing the length of the third-type connection line  23 . As a result, the load of the second signal line  12  that is electrically connected to the third-type connection line  23  is consistent with the load of other signal line  1  that does not pass the second light-transmission hole H 2 . 
     Exemplarily, as shown in  FIG.  9   , the display panel further includes another type of signal line  6  extending along the first direction x. In some embodiments of the present disclosure, the signal line  1  extending along the second direction y includes a data line, and the signal line  6  extending along the first direction x includes a scan line. 
     Exemplarily, as shown in  FIG.  1   , the first A connection line  211  includes a first connection sub-line  2111  and a second connection sub-line  2112 , and an extending direction of the first connection sub-line  2111  intersects an extending direction of the second connection sub-line  2112 . Exemplarily, as shown in  FIG.  1   , the first connection sub-line  2111  extends along the first direction x, and the second sub-line  2112  extends along the second direction y. 
     Exemplarily, in some embodiments, the first connection sub-line  2111  and the second connection sub-line  2112  are arranged in a same layer, so as to simplify the manufacturing process. Alternatively, each of the first connection sub-line  2111  and the second connection sub-line  2112  may be arranged in a layer different from the layer of the signal line  1 , and the signal line  1  is electrically connected to the first connection sub-line  2111  or the second connection sub-line  2112  via a through-hole. 
     Alternatively, in some embodiments, the first connection sub-line  2111  and the second connection sub-line  2112  are located in different layers and are electrically connected via a through-hole. 
     Exemplarily, in some embodiments, one of the first connection sub-line  2111  and the second connection sub-line  2112  is located in the first non-display region NA 1 . 
       FIG.  10    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure.  FIG.  11    is a partially enlarged view of a display panel according to some embodiments of the present disclosure.  FIG.  12    is a cross-sectional view of a dummy pixel and a sub-pixel according to some embodiments of the present disclosure. In some embodiments, as shown in  FIG.  10   ,  FIG.  11    and  FIG.  12   , the display panel includes a dummy pixel DP in the first non-display region NA 1 . The arrangement of the dummy pixel DP can ensure a density uniformity of the circuit pattern in the display panel, thereby optimizing the etching effect. 
     Exemplarily, in a direction perpendicular to the plane of the display panel, one of the first connection sub-line  2111  and the second connection sub-line  2112  at least partially overlaps the dummy pixel DP. With such a configuration, it does not need to provide an additional space in the first non-display region NA 1  for arranging the first A connection line  211 , thereby being beneficial to reducing the width of the first non-display region NA 1 .  FIG.  11    illustrates an example in which the first connection sub-line  2111  partially overlaps the dummy pixel DP. 
     In some exemplary embodiments of the present disclosure, the dummy pixel DP includes a dummy pixel driving circuit. The dummy pixel driving circuit and the pixel circuit in the display region AA may have a same structure. In some embodiments, the dummy pixel driving circuit may be formed by deleting some elements from the structure of the pixel circuit in the display region AA. As shown in  FIG.  12   , the sub-pixel P in the display region AA includes a pixel driving circuit  31 , a connection electrode  32 , and a light-emitting element  33 . The light-emitting element  33  includes a first electrode  331 , a light-emitting layer  330 , and a second electrode  332  that are stacked in the thickness direction of the display panel. The pixel driving circuit  31  is electrically connected to the light-emitting element  33  through the connection electrode  32 . Exemplarily, as shown in  FIG.  12   , an insulation layer  30  is provided between the pixel driving circuit  31  and the light-emitting element  33 , and the insulation layer  30  includes a though-hole. The through-hole is filled by the connection electrode  32 . 
     It should be noted that in embodiments of the present disclosure, two or more transistors are provided in the pixel driving circuit  31  according to the function that needs to be achieved by the pixel driving circuit  31 . In  FIG.  12   , one transistor T in the pixel driving transistor  31  is shown for illustration. 
     In some exemplary embodiments of the present disclosure, as shown in  FIG.  12   , the dummy pixel DP does not include the above connection electrode  32 . In some exemplary embodiments, at least one part of the first A connection line  211  is arranged in the same layer as the connection electrode  32  in the display region. In an alternative embodiment, during the formation of the dummy pixel DP, a step of forming the though-hole in the insulation layer  30  may be omitted, so as to avoid the connection of the dummy pixel driving circuit and the dummy light-emitting element. 
     In some exemplary embodiments of the present disclosure, as shown in  FIG.  12   , the dummy pixel DP does not include one or more layers of the light-emitting element. In this case, at least one part of the first A connection line  211  may be arranged in the same layer as the electrode of the light-emitting element  33 . For example, the first A connection line  211  and the first electrode  331  of the light-emitting element  33  may be arranged in a same layer, so as to simplify the manufacturing process of the display panel. 
     In addition, if the light-emitting element in the dummy pixel DP includes the electrode, the light-emitting element in the dummy pixel DP may emit light due to a floating state of the electrode. In some embodiments, the light-emitting element in the dummy pixel DP does not include the electrode, and thus the above-mentioned issue is avoided, thereby improving the display effect of the display panel. 
       FIG.  13    is a partially enlarged view of a first non-display region of a display panel according to some embodiments of the present disclosure. In some embodiments of the present disclosure, the display panel includes a constant signal line VL located in the first non-display region NM. In the direction perpendicular to the plane of the display panel, one of the first connection sub-line  2111  and the second connection sub-line  2112  of the first A connection line  211  at least partially overlaps the constant signal line VL. This arrangement can reduce the width of the first non-display region NA 1 . Moreover, this arrangement can reduce the interference of other signal lines to the first A connection line  211 , thereby being beneficial to ensuring the accuracy of the signal transmitted by the first A connection line  211 . 
     In some exemplary embodiments of the present disclosure, as shown in  FIG.  1   , the second non-display region NA 2  located between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  includes a first region A 1  and a second region A 2 . The density of the first-type connection line  21  in the first region A 1  is greater than the density of the first-type connection line  21  in the second region A 2 , so that the light transmittance of the second region A 2  is greater than the light transmittance of the first region A 1 .  FIG.  1    illustrates an example in which no first-type connection line  21  is arranged in the second region A 2 . In some exemplary embodiments, the first region A 1  is located at a side of the second region A 2  close to the first light-transmission sub-hole H 11  or the second light-transmission sub-hole H 12 . In some exemplary embodiments, the optical element may be arranged in the second region A 2 , so as to ensure the light sensing effect of the optical element, thereby enriching the functions of the display panel and improving the user experience. 
     In some exemplary embodiments of the present disclosure, the second non-display region NA 2  between the first light-transmission sub-hole H 11  and the second light-transmission sub-hole H 12  may be provided with a dummy pixel, and the arrangement manner of the dummy pixel in the second non-display region NA 2  may be same as the arrangement manner of the dummy pixel in the first non-display region NA 1 , which is not repeated herein. In the embodiments in which the second non-display region NA 2  is provided with the dummy pixel, the first-type connection line  21  has at least one part that passes the second non-display region NA 2  and overlaps the dummy pixels, so as to fully utilize the space of the second non-display region NA 2 . 
       FIG.  14    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure. In some exemplary embodiments of the present disclosure, the display panel further includes at least two light-transmission holes H, and the display region AA at least partially surrounds the at least two light-transmission holes H. The light-transmission hole H has a first end D 1  and a second end D 2  that are oppositely arranged along the first direction x. The first end D 1  of the light-transmission hole H is located at a side of the second end of the light-transmission hole H away from the first non-display region NA 1 . 
     As shown in  FIG.  14   , the signal lines  1  further include a third signal line  13 . For a same light-transmission hole H, a distance between the third signal line  13  and the first end D 1  of the light-transmission hole H is smaller than a distance between the third signal line  13  and the second end D 2  of the light-transmission hole H. In some embodiments of the present disclosure, two segments of the third signal line  13  that are located at two sides of the light-transmission hole H are electrically connected to each other through a fourth-type connection line  24 . The fourth-type connection line  24  has at least one part located in the display region AA, and the fourth-type connection line  24  is located between the light-transmission hole H and the first non-display region NA 1 . In other words, at least two light-transmission holes H are located at a same side of the fourth-type connection line  24 . Compared with an arrangement in which the fourth-type connection line  24  is located between two adjacent light-transmission holes H, such an arrangement can reduce the number of connection lines arranged between two adjacent light-transmission holes H; moreover, such an arrangement can avoid that a distance between the connection lines between two adjacent light-transmission holes H is too small, thereby being compatible with the current process capabilities. 
     In some exemplary embodiments of the present disclosure, multiple sub-pixels may be arranged between two light-transmission holes H. That is, the region between two light-transmission holes H belongs to the display region AA. With the above-mentioned arrangement provided by the embodiments of the present disclosure, the number of the connection lines in the display region AA between two light-transmission holes H can be reduced, the light transmittance of the display region AA between two light-transmission holes H is ensured, and the signal interference between the connection line and other signal line that is located in the display region AA between two light-transmission holes H is reduced. 
     In some exemplary embodiments of the present disclosure, as shown in  FIG.  14   , the signal lines  1  further include a fourth signal line  14 . For a same light-transmission hole H, a distance between the fourth signal line  14  and the first end D 1  of the light-transmission hole H is greater than a distance between the fourth signal line  14  and the second end D 2  of the light-transmission hole H. 
     In some exemplary embodiments of the present disclosure, the display panel may include multiple fourth-type connection lines  24  that are located between the light-transmission hole H and the first non-display region NA 1 . In some embodiments of the present disclosure, as shown in  FIG.  14   , for one or more fourth signal lines  14  that are disconnected by the light-transmission hole H, two segments of the fourth signal line  14  that are located at two sides of the light-transmission hole H are electrically connected to each other by the fourth-type connection line  24 . 
     In some exemplary embodiments of the present disclosure, as shown in  FIG.  14   , the fourth-type connection line  24  that is electrically connected to the fourth signal line  14  is located between the light-transmission hole H and the fourth-type connection line  24  that is electrically connected to the third signal line  13 . In some exemplary embodiments of the present disclosure, the fourth-type connection line  24  that is electrically connected to the fourth signal line  14  and the fourth-type connection line  24  that is electrically connected to the third signal line  13  may be arranged in a same layer. With such a configuration, intersecting of the fourth-type connection lines  24  that are connected to different signal lines  1  is avoided, which can simplify the manufacturing process of the display panel and ensure a well insulation of different fourth-type connection lines  24 . 
       FIG.  15    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure. In some exemplary embodiments of the present disclosure, as shown in  FIG.  15   , the arranging direction of the two adjacent light-transmission holes H may intersect both the first direction x and the second direction y, so as to improve the arrangement flexibility of the light-transmission holes H. 
       FIG.  16    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure. In some exemplary embodiments of the present disclosure, as shown in  FIG.  16   , the display panel further includes a compensation line  3 , and at least one of the fourth-type connection lines  24  is electrically connected to the compensation line  3 . The compensation line  3  can improve the load uniformity of the signal lines that are electrically connected to different fourth-type connection lines  24  and have different lengths, thereby improving the display uniformity of the display panel. 
     In some exemplary embodiments of the present disclosure, as shown in  FIG.  16   , the fourth-type connection line  24  includes a first connection sub-line  241  and a second connection sub-line  242  that have different extending directions. The compensation line  3  extends from an intersection of the first connection sub-line  241  and the second connection sub-line  242  along a direction away from the first connection sub-line  241  or the second connection sub-line  242 . In the exemplary example illustrated in  FIG.  16   , two compensation lines  3  are provided, one of the two compensation lines  3  is parallel to the first connection sub-line  241 , and the other one of the two compensation lines  3  is parallel to the second connection sub-line  242 . 
     In some exemplary embodiments of the present disclosure, the compensation line  3  may be arranged in the same layer as the first connection sub-line  241  or the second connection sub-line  242 , so as to simplify the manufacturing process of the display panel. In some embodiments of the present disclosure, in addition to improving the load uniformity of different signal lines, the compensation line  3  can also improve the light reflectivity uniformity between a position provided with the fourth-type connection line  24  and a position not provided with the fourth-type connection line  24  in the display panel, thereby being beneficial to improving the display effect of the display panel. 
     In some exemplary embodiments of the present disclosure, a cross-sectional area of the fourth-type connection line  24  that is electrically connected to the third signal line  13  is different from a cross-sectional area of the fourth-type connection line  24  that is electrically connected to the fourth signal line  14 , so as to improve the load uniformity of the signal lines  1  that are electrically connected to different fourth-type connection lines  24  and have different lengths. 
     In some exemplary embodiments of the present disclosure, different fourth-type connection lines  24  have different electrical conductivities, so as to improve the load uniformity of the signal lines  1  that are electrically connected to different fourth-type connection lines  24  and have different lengths. 
     In some exemplary embodiments of the present disclosure, both the cross-sectional areas and the electrical conductivities of different fourth-type connection lines  24  may be adjusted, so as to improve the load uniformity of the signal lines  1  that are electrically connected to different fourth-type connection lines  24  and have different lengths. 
       FIG.  17    is a schematic diagram of yet another display panel according to some embodiments of the present disclosure. In some exemplary embodiments of the present disclosure, as shown in  FIG.  17   , at least two light-transmission holes H include a third light-transmission hole H 3 , a fourth light-transmission hole H 4 , and a fifth light-transmission hole H 5 . The fifth light-transmission hole H 5  is located between the third light-transmission hole H 3  and the fourth light-transmission hole H 4 . 
     The signal lines  1  further include a fifth signal line  15 . Along the second direction y, the fifth signal line  15  has two segments located at two sides of the fifth light-transmission hole H 5 . A distance between the fifth signal line  15  and the second end of the third light-transmission hole H 3  is smaller than a distance between the fifth signal line  15  and the second end of fourth light-transmission hole H 4 . 
     In some embodiments of the present disclosure, at least one of the fourth-type connection lines  24  is electrically connected to the fifth signal line  15 . Such an arrangement can reduce the number of connection lines between the third light-transmission hole H 3  and the fifth light-transmission hole H 5 . If the region between the third light-transmission hole H 3  and the fifth light-transmission hole H 5  is provided with sub-pixels and functions as the display region AA, the above-mentioned arrangement can reduce the number of connection lines between the third light-transmission hole H 3  and the fifth light-transmission hole H 5  compared with the arrangement that the fourth-type connection line electrically connected to the fifth signal line  15  is arranged between the third light-transmission hole H 3  and the fifth light-transmission hole H 5 . Moreover, the above-mentioned arrangement can avoid that the distance between the connection lines between two adjacent light-transmission holes H is too small, thereby being compatible with the current process capabilities. In addition, the above-mentioned arrangement can ensure the light transmittance of the display region AA between the third light-transmission hole H 3  and the fifth light-transmission hole H 5 , and reduce the signal interference between the connection line and other signal line located in the display region AA between the third light-transmission hole H 3  and the fifth light-transmission hole H 5 . 
     In some exemplary embodiments of the present disclosure, as shown in  FIG.  17   , the fourth-type connection line  24  that is electrically connected to the fifth signal line  15  is located at a side of the fourth-type connection line  24  that is electrically connected to the third signal line  13  away from the third light-transmission hole H 3 . With such a configuration, the fourth-type connection line  24  that is electrically connected to the fifth signal line  15  and the fourth-type connection line  24  that is electrically connected to the third signal line  13  may be arranged in a same layer, and do not intersect each other, thereby simplifying the manufacturing process of the display panel while ensuring the well insulation of the two fourth-type connection lines  24 . 
     In some exemplary embodiments of the present disclosure, as shown in  FIG.  14   ,  FIG.  15   ,  FIG.  16    and  FIG.  17   , the display panel further includes a sixth signal line  16  located in the display region AA. The sixth signal line  16  is closer to the first end D 1  of one light-transmission hole H than the second end D 2  of the same light-transmission hole H. Two segments of the sixth signal line  16  that are located at two sides of the light-transmission hole H are electrically connected to each other through a fifth-type connection line  25 . The fifth-type connection line  25  has at least one part located in the display region AA. In some exemplary embodiments of the present disclosure, as shown in  FIG.  14   ,  FIG.  15   ,  FIG.  16    and  FIG.  17   , the fifth-type connection line  25  has at least one part located between two adjacent light-transmission holes H. With such a configuration, the length of the fifth-type connection line  25  can be set short, which is beneficial to reducing the load. 
     In some exemplary embodiments of the present disclosure, as shown in  FIG.  14   ,  FIG.  15   ,  FIG.  16    and  FIG.  17   , along the second direction y, a virtual extension line of the third signal line  13  and a virtual extension line of the sixth signal line  16  pass a same light-transmission hole H, and the third signal line  13  is located at a side of the sixth signal line  16  close to the second end D 2  of this light-transmission hole H. That is, when the space between two light-transmission holes H is limited, this space is preferable to arrange the connection line that is electrically connected to the signal line close to this space, so as to avoid a long connection line, which is beneficial to reducing the load. 
     Embodiments of the present disclosure further provide a display device.  FIG.  18    is a schematic diagram of a display device according to some embodiments of the present disclosure. As shown in  FIG.  18   , the display device includes the display panel  100  described above. A specific structure of the display panel  100  has been explained in the above embodiments and will not be repeatedly described herein. Of course, the display device shown in  FIG.  20    is only a schematic illustration, and the display device can be any electronic device with a display function, such as a mobile phone, a tablet computer, a notebook computer, an electronic paper reader, a television or the like. 
     The above embodiments are merely some embodiments of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent substitutions, and improvements made within the principle of the present disclosure shall fall into the scope of the present disclosure.