DISPLAY PANEL AND PREPARATION METHOD THEREFOR

A display panel and a preparation method therefor are provided. The display panel includes: a driving backplate, a first surface of which is provided with normal bonding areas and redundant bonding areas, at least one of first distances between every two normal bonding areas, which are adjacent to each other is greater than at least one of second distances between each normal bonding area and a corresponding redundant bonding area which is adjacent to the normal bonding area, and at least one normal bonding area and at least one redundant bonding area adjacent thereto constitute a bonding group; and a light emitting layer, located on the first surface and including sub-pixels electrically connected to the normal bonding areas or the redundant bonding areas, and the normal bonding area and the redundant bonding area of the same bonding group are electrically connected to sub-pixels with the same emitting color.

TECHNICAL FIELD

The present disclosure relates to the field of display, and in particular to a display panel and a preparation method of the display panel.

BACKGROUND

Micro-LED, as a novel display technology, is receiving more and more widespread attention. However, the yield of the mass transfer technology for Micro-LEDs is relatively low at present, and it needs to repair defective pixels after transfer to meet display standards. Due to the tight arrangement of Micro-LEDs, how to improve both the yield of the mass transfer and the yield of repair is an urgent technical problem to be solved.

SUMMARY OF THE DISCLOSURE

The present disclosure provides a display panel and a preparation method of the display panel.

In one aspect, a technical solution adopted by the present disclosure is to provide a display panel. The display panel includes: a driving backplane, a first surface of the driving backplane is provided with a plurality of normal bonding areas and a plurality of redundant bonding areas; a distance between every two of the plurality of normal bonding areas adjacent to each other is defined as a first distance; a distance between each of the plurality of normal bonding areas and a corresponding one of the redundant bonding areas which is adjacent to the each of the plurality of normal bonding areas is defined as a second distance, and at least one of the first distances is greater than at least one of the second distances; and at least one of the plurality of normal bonding areas and at least one of the plurality of redundant bonding areas adjacent to the at least one of the plurality of normal bonding areas constitute a bonding group; and a light emitting layer, located on the first surface and comprising a plurality of sub-pixels, the plurality of sub-pixels are electrically connected to the normal bonding areas or the redundant bonding areas, and the normal bonding area and the redundant bonding area of the same bonding group are configured to be electrically connected to sub-pixels with the same emitting color.

In another aspect, a technical solution adopted by the present disclosure is to provide a preparation method of a display panel. The method includes: providing a driving backplane; a first surface of the driving backplane is provided with a plurality of normal bonding areas and a plurality of redundant bonding areas; a distance between every two of the plurality of normal bonding areas adjacent to each other is defined as a first distance; a distance between each of the plurality of normal bonding areas and a corresponding one of the redundant bonding areas which is adjacent to the each of the plurality of normal bonding areas is defined as a second distance, and at least one of the first distances is greater than at least one of the second distances; and at least one of the plurality of normal bonding areas and at least one of the plurality of redundant bonding areas adjacent to the at least one of the plurality of normal bonding areas constitute a bonding group; disposing a plurality of sub-pixels in the normal bonding areas of the driving backplane; and introducing a patched sub-pixel with the same emitting color as a defective sub-pixel in the redundant bonding area, in response to the sub-pixel bonded to the normal bonding area of the same bonding group being determined to be the defective sub-pixel.

Different from the related art, the present disclosure may have the following technical effects: on one hand, the driving backplane of the display panel provided by some embodiments of the present disclosure is provided with the plurality of normal bonding areas and the plurality of redundant bonding areas, the normal bonding areas and the redundant bonding areas adjacent to the normal bonding areas may constitute the bonding group. In a practical application process, when the sub-pixel bonded to the normal bonding area is determined to be a defective pixel, a patched sub-pixel with the same emitting color as the defective pixel may be introduced in the redundant bonding area of the same bonding group, increasing the yield of repair compared with in-situ repair. On the other hand, in some embodiments of the present disclosure, at least one of the first distances between every two of the plurality of normal bonding areas, which are adjacent to each other is greater than at least one of the second distances between each of the plurality of normal bonding areas and a corresponding one of the redundant bonding areas which is adjacent to the each of the plurality of normal bonding areas. During the mass transfer process, when the sub-pixels are bonded to the normal bonding areas, the above design may increase a distance between adjacent sub-pixels, reduce interference between adjacent sub-pixels, and reduce probability of rotation and offset of the sub-pixels to improve the yield of transfer. The design may appropriately increase convex areas of transfer heads configured to transfer the sub-pixels, so as to increase tolerances of the offset of the sub-pixels and improve the yield of transfer.

DETAILED DESCRIPTION

The technical solutions in the embodiments of the present disclosure will be clearly and completely described below in combination with accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are merely parts of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments of the present disclosure, any other embodiments obtained by those skilled in the art without inventive effort fall within a protection scope of the present disclosure.

FIG.1is a schematic structural view of a display panel according to an embodiment of the present disclosure, andFIG.2is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to an embodiment of the present disclosure. The display panel may be a Micro-LED display panel, etc. The display panel1includes a driving backplane10and a light emitting layer12located on a first surface100of the driving backplane10.

As shown inFIG.2, the first surface100of the driving backplane10is provided with a plurality of normal bonding areas1020and a plurality of redundant bonding areas1022. A distance between every two of the plurality of normal bonding areas1020adjacent to each other is defined as a first distance D1. A distance between each normal bonding area1020and a corresponding one of the redundant bonding areas1022which is adjacent to the each normal bonding area1020is defined as a second distance D2. At least one of the first distances D1is greater than at least one of the second distances D2. At least one normal bonding area1020and at least one redundant bonding area1022adjacent to the at least one normal bonding area1020may constitute one bonding group102. In some embodiments, the first distance D1may be a distance between edges of the every adjacent two normal bonding areas1020, and the second distance D2may be a distance between an edge of each normal bonding area1020and an edge of the corresponding redundant bonding area1022adjacent to the each normal bonding area1020. Or, the first distance D1may be a distance between center points of the every adjacent two normal bonding areas1020, and the second distance D2may be a distance between a center point of each normal bonding area1020and a center point of the corresponding redundant bonding area1022adjacent to the each normal bonding area1020. In some embodiments, one normal bonding area1020and one redundant bonding area1022adjacent to the normal bonding area1020may constitute one bonding group102. In other embodiments, one normal bonding area1020and a plurality of redundant bonding areas1022adjacent to the one normal bonding area1020may also constitute one bonding group102.

The light emitting layer12includes a plurality of sub-pixels120. The sub-pixels120may be Micro-LEDs, etc. The sub-pixels120may emit red light, green light, or blue light, etc. . . . The sub-pixels120are electrically connected to the normal bonding areas1020or the redundant bonding areas1022. The normal bonding area1020and the redundant bonding area1022of the same bonding group102are configured to be electrically connected to sub-pixels120with the same emitting color.

In this embodiment, an appearance structure of the normal bonding area1020and an appearance structure of the redundant bonding area1022may be the same, and a distinguishing standard of the normal bonding area1020and the redundant bonding area1022is mainly in that priority of the normal bonding area1020and priority of the redundant bonding area1022are different from each other when the sub-pixels120of the light emitting layer12are bonded to the normal bonding areas1020or the redundant bonding areas1022. In some embodiments, during the mass transfer process, the sub-pixels120are preferentially bonded to the normal bonding areas1020of the bonding group102. When the sub-pixel120bonded to the normal bonding area1020is determined to be a defective sub-pixel, the defective sub-pixel is removed. Or, the defective sub-pixel is remained or retained when the defective sub-pixel is disconnected, a patched sub-pixel is introduced into the redundant bonding area1022of the same bonding group102, and an emitting color of the patched sub-pixel is the same as an emitting color of the defective sub-pixel when the defective sub-pixel emits light as usual or emits light normally. That is, a bonding time point of the sub-pixel120electrically connected to the normal bonding area1020is earlier than a bonding time point of the sub-pixel120electrically connected to the redundant bonding area1022, which means the time point for bonding the sub-pixel120to the normal bonding area1020is earlier than the time point for bonding the sub-pixel120to the redundant bonding area1022. For the same boding group102, the normal bonding area1020is electrically connected to the sub-pixels120in preference to or prior to the redundant bonding areas1022.

In some embodiments, for the same bonding group102, only one sub-pixel120is disposed in the normal bonding area1020or the redundant bonding area1022. Or, for the same bonding group102, one sub-pixel120is disposed in the normal bonding area1020, another sub-pixel120is disposed in the redundant bonding area1022, the sub-pixel120in the normal bonding area1020is disconnected from a corresponding pixel driving circuit, and the sub-pixel120in the redundant bonding area1022is electrically connected to the corresponding pixel driving circuit. SinceFIG.2is a schematic partial view of the display panel1shown inFIG.1before the defective pixel is repaired, it may be considered that an area covered by the sub-pixel120inFIG.2is the normal bonding area1020, and an area size of the normal bonding area1020and an area size of the redundant bonding area1022may be the same as an area size of the sub-pixel120.

In some embodiments, for the display panel1, a number of the sub-pixels120electrically connected to the normal bonding areas1020on the display panel1is greater than a number of sub-pixels120electrically connected to the redundant bonding areas1022. For example, a ratio of the number of sub-pixels120electrically connected to the normal bonding areas1020to the number of sub-pixels120electrically connected to the redundant bonding areas1022may be much greater than 100. In some embodiments, all the sub-pixels120are electrically connected to the normal bonding areas1020. In some embodiments, at least one of the plurality of redundant bonding areas1022is not electrically connected to (i.e., disconnected from) the corresponding sub-pixel120.

On one hand, some embodiments of the present disclosure introduce a redundant repair method, which reduces repair difficulty and increases the yield of repair compared with in-situ repair. On the other hand, in some embodiments of the present disclosure, at least one of the first distances D1between every two of the plurality of normal bonding areas1020, which are adjacent to each other, is greater than at least one of the second distances D2between each normal bonding area1020and a corresponding one of the redundant bonding areas1022adjacent to the each normal bonding area1020. During the mass transfer process, when the sub-pixels120are bonded to the normal bonding areas1020, the above design may increase distances between adjacent sub-pixels120, reduce interference between adjacent sub-pixels120, and reduce the probability of rotation and offset of the sub-pixels120, so as to improve the yield of transfer. The design may appropriately increase convex areas of transfer heads configured to transfer the sub-pixels120, so as to increase tolerances of the offset of the sub-pixels120and improve the yield of transfer.

In one embodiment, as shown inFIG.2, the plurality of normal bonding areas1020and the plurality of redundant bonding areas1022are arranged in an array along a first direction X and a second direction Y, and the first direction X and the second direction Y are intersected with each other. In some embodiments, the first direction X and the second direction Y are substantially perpendicular to each other. At least one of the first distances D1between every two of the plurality of normal bonding areas1020adjacent to each other in the first direction X is greater than at least one of the second distances D2between each normal bonding area1020and a corresponding one of the redundant bonding areas1022adjacent to the each normal bonding area1020in the first direction X or the second direction Y. In some embodiments, at least one of the first distances D1between every two of the plurality of normal bonding areas1020adjacent to each other in the second direction Y is greater than at least one of the second distances D2between each normal bonding area1020and a corresponding one of the redundant bonding areas1022adjacent to the each normal bonding area1020in the first direction X or the second direction Y. In some cases, as shown inFIG.2, two adjacent normal bonding areas1020may also be arranged in an oblique direction, that is, a direction intersected with the first direction X or the second direction Y inFIG.2. At this time, at least one of the first distances D1between every two of the plurality of normal bonding areas1020adjacent to each other in the oblique direction is still greater than at least one of the second distances D2between each normal bonding area1020and a corresponding one of the redundant bonding areas1022adjacent to the each normal bonding area1020in the first direction X or the second direction Y. The plurality of normal bonding areas1020and the plurality of redundant bonding areas1022are arranged in a regular manner, and the producing process is easy to implement. In some embodiments, the emitting colors of the sub-pixels120bonded in the two adjacent normal bonding areas1020may be the same or different, which is not limited in some embodiments of the present disclosure.

As further shown inFIG.2, for each of at least one pair of normal bonding areas1020adjacent to each other in at least one of the first direction X and the second direction Y, a corresponding one of the redundant bonding areas1022is arranged between one of the pair of the normal bonding areas1020and the other of the pair of normal bonding areas1020. This design may increase the first distance D1between two adjacent normal bonding areas1020. During the mass transfer process, when the sub-pixels120are bonded to the normal bonding areas1020, the above design may further reduce the interference between the adjacent sub-pixels120, and reduce the probability of rotation and offset of the sub-pixels120, so as to improve the yield of transfer. Besides, the design may increase the convex areas of the transfer heads configured to transfer the sub-pixels, so as to increase the tolerances of the offset of the sub-pixels.

As shown inFIG.2, a plurality of adjacent sub-pixels120constitute at least one pixel unit (not labeled), and a plurality of bonding groups102electrically connected to the at least one pixel unit constitute at least one combination unit104. For each combination unit104, the normal bonding areas1020and the redundant bonding areas1022of the each combination unit104are arranged in two rows in the first direction X, the normal bonding areas1020of the each combination unit104are alternately arranged in the two rows (i.e., alternately arranged up and down), and the redundant bonding areas1022of the each combination unit104are alternately arranged in the two rows (i.e., alternately arranged up and down). This design may make the distances between adjacent normal bonding areas1020larger. During the mass transfer process, when the sub-pixels120are bonded to the normal bonding areas1020, the above design may further reduce the interference between the adjacent sub-pixels120, and reduce the probability of rotation and offset of the sub-pixels120, so as to improve the yield of transfer. Besides, the design may increase the convex areas of the transfer heads configured to transfer the sub-pixels, so as to increase the tolerances of the offset of the sub-pixels.

In some embodiments, as shown inFIG.2, a number of every two adjacent sub-pixels120arranged in the oblique direction is greater than a number of every two adjacent sub-pixels120arranged in the same row in the first direction X or the second direction Y. The oblique direction is intersected with the first direction X and the second direction Y. For example, three sub-pixels120of one combination unit104inFIG.2are taken as an example, a red sub-pixel R and a green sub-pixel G are adjacent in a first oblique direction, the green sub-pixel G and a blue sub-pixel B are adjacent in a second oblique direction, and the first oblique direction is different from the second oblique direction, but both the first oblique direction and the second oblique direction are intersected with the first direction X and the second direction Y. The above design may make the distance between two adjacent sub-pixels120as large as possible.

In one embodiment, the driving backplane10further includes a plurality of pixel driving circuits (not shown), and the normal bonding areas1020and the redundant bonding areas1022of the same bonding group102are electrically connected to the same pixel driving circuit. This design may save wiring spaces of the pixel driving circuits, and be more suitable for high PPI or closely-arranged sub-pixel arrangement scenarios. In some embodiments, structures of the pixel driving circuits may be any one structure in the related art, for example, 2T1C, 7T1C, etc., which is not limited in some embodiments of the present disclosure.

In some embodiments, the sub-pixels120may be horizontal light-emitting elements. A side of each sub-pixel120facing the first surface100is provided with a first electrode (not shown) and a second electrode (not shown). As shown inFIG.2, each normal bonding area1020or redundant bonding area1022includes a first electrode bonding area1060configured to be electrically connected to the first electrode and a second electrode bonding area1062configured to be electrically connected to the second electrode. For example, the first electrode corresponding to the first electrode bonding area1060labeled inFIG.2is a P-electrode, and the second electrode corresponding to the second electrode bonding area1062labeled inFIG.2is an N-electrode. In other embodiments, the first electrode corresponding to the first electrode bonding area1060may also be the N-electrode, and the second electrode corresponding to the second electrode bonding area1062may also be the P-electrode. In some embodiments, two first electrode bonding areas1060of the same bonding group102are electrically connected to an output terminal of the same pixel driving circuit. That is, the normal bonding areas1020and the redundant bonding areas1022of the same bonding group102are electrically connected to the same pixel driving circuit, and the sub-pixels arranged in the normal bonding areas1020and the patched sub-pixels arranged in the redundant bonding areas1022may be driven by the same pixel driving circuit. This design may save the wiring spaces of the pixel driving circuits, and be more suitable for high PPI or closely-arranged sub-pixel arrangement scenarios.

In one application scenario, as shown inFIG.2, the normal bonding areas1020and the redundant bonding areas1022of the same bonding group102are arranged adjacently along the first direction X, and multiple bonding groups102of the same combination unit104are arranged at intervals along the second direction Y. In the above design, the redundant bonding area1022is designed along the first direction X of the normal bonding area1020, the structural is relatively simple and the producing process is easy to implement.

In some embodiments, as shown inFIG.2, the plurality of normal bonding areas1020and the plurality of redundant bonding areas1022arranged in the same row are alternately arranged at intervals in the second direction Y. The normal bonding areas1020and the redundant bonding areas1022in upper and lower rows in the first direction X are arranged alternately in an opposite manner, and the upper and lower rows are aligned with each other.

On this basis, as shown inFIG.2, in the first direction X, two first electrode bonding areas1060of the same bonding group102face each other and are arranged at intervals. The two first electrode bonding areas1060of the same bonding group102are located between two second electrode bonding areas1062. That is, in the first direction X, the first electrode bonding areas1060and the second electrode bonding areas1062of the same bonding group102are sequentially arranged at intervals in the following manner: the second electrode bonding area1062, the first electrode bonding area1060, the first electrode bonding area1060, and the second electrode bonding area1062. In this case, an orthographic projection of the output terminal of the pixel driving circuit projected on the first surface100in the first direction X (as shown by a dotted line box labeled108inFIG.2) is located between the two first electrode bonding areas1060. The above structure is relatively simple and the producing process is easy to implement.

In some embodiments, as shown inFIG.2andFIG.3,FIG.3is a schematic top view of a pixel driving circuit and associated wiring shown inFIG.2according to an embodiment of the present disclosure. In some embodiments, the driving backplane10includes a thin film transistor layer and an insulating layer disposed above the thin film transistor layer. A plurality of pixel driving circuits103are located in the thin film transistor layer, and a surface of the insulating layer facing away from the thin film transistor layer forms the first surface100. The first electrode bonding areas1060and the second electrode bonding areas1062may be exposed from the first surface100of the driving backplane10for bonding with the sub-pixels120. In this case, a position of the insulating layer corresponding to the output terminal of the pixel driving circuit103may define a conductive hole (i.e., the position indicated by the dotted line box labeled108inFIG.2andFIG.3). The conductive hole is further electrically connected to the two first electrode bonding areas1060disposed on opposite sides of the conductive hole through metal wirings. It may be seen fromFIG.2andFIG.3that, the output terminals of the pixel driving circuits103are arranged at intervals along the second direction Y, so that the pixel driving circuits103may be repeatedly arranged in the second direction Y, thereby reducing the layout difficulty of the pixel driving circuits103.

As shown inFIG.2, the pixel unit inFIG.2includes three adjacent sub-pixels120(a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B). The combination unit104includes three bonding groups102electrically connected to the sub-pixels120in the corresponding pixel unit. Three normal bonding areas1020of the combination unit104are arranged alternately up and down, and three redundant bonding areas1022of the combination unit104are arranged alternately up and down. In some embodiments, the display panel1includes multiple repeating units106. Two adjacent combination units104arranged in the second direction Y constitute one repeating unit106. A plurality of normal bonding areas1020of the repeating unit106are arranged alternately up and down. A plurality of redundant bonding areas1022of the repeating unit106are arranged alternately up and down. The design of the repeating units106may reduce the complexity for producing the display panel1.

Of course, in other embodiments, the combination units104inFIG.2may also be arranged in other manner. For example, as shown inFIG.4,FIG.4is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. The pixel unit shown inFIG.4includes three adjacent sub-pixels120(a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B). The combination unit104includes three bonding groups102electrically connected to the sub-pixels120in the corresponding pixel unit. In the first direction X, the combination units104of at least one pair of combination units104adjacent to each other are arranged axially symmetrically. At least parts of the normal bonding areas1020of two adjacent combination units104arranged axially symmetrically, which correspond to the sub-pixels with the same emitting color are arranged adjacent to each other. This design may make parts of the two sub-pixels120in the normal bonding areas1020in two bonding groups102adjacent to each other in the first direction X may be transferred and bonded at the same time or simultaneously, so as to improve the bonding efficiency. Besides, the two sub-pixels will not be affected by the sub-pixels120on the remaining normal bonding areas1020during the bonding transfer process, so as to improve the yield of bonding. For example, as shown inFIG.4, two adjacent blue sub-pixels having no redundant bonding area1022disposed there between in the first direction X may be transferred and bonded at the same time. The two blue sub-pixels will not be squeezed or collided by adjacent red sub-pixels or green sub-pixels during the bonding process due to the redundant bonding areas1022surrounding the two blue sub-pixels.

In some embodiments, as shown inFIG.4, a third distance D3between two adjacent normal bonding areas1020from two adjacent combination units104in the first direction X is shorter than a fourth distance D4between another two adjacent normal bonding areas1020of the same combination unit104. This design may increase the arrangement density of the pixels to improve the display effect. In some embodiments, the third distance D3and the fourth distance D4may be the distance between edges of two adjacent normal bonding areas1020. Or, the third distance D3and the fourth distance D4may be the distance between center points of two adjacent normal bonding areas1020.

In some embodiments, as shown inFIG.4, four combination units104adjacent to each other in the first direction X and the second direction Y (the four adjacent combination units104in the up, down, left, and right directions) constitute one repeating unit106. The normal bonding areas1020and the redundant bonding areas1022in the same row of the repeating unit106are arranged alternately in the second direction Y. This design may reduce the difficulty of producing process.

In another application scenario, as shown inFIG.5,FIG.5is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. The normal bonding areas1020and the redundant bonding areas1022of the same bonding group102are arranged at intervals along the second direction Y. Multiple bonding groups102of the same combination unit104are arranged in two rows along the first direction X, and the bonding groups102in the two rows are staggered or misaligned or offset from each other. In some embodiments, the amount of misalignment or offset between the bonding groups102in the two rows is one redundant bonding area1022or one normal bonding area1020. In the above design, the redundant bonding area1022is designed along the second direction Y of the normal bonding area1020, the structure is relatively simple and the producing process is easy to implement.

In some embodiments, as shown inFIG.5, the plurality of normal bonding areas1020and the plurality of redundant bonding areas1022arranged in the same row are alternately arranged at intervals in the second direction Y. The normal bonding areas1020and the redundant bonding areas1022in upper and lower rows are arranged alternately in the first direction X in the same manner, and the normal bonding areas1020and the redundant bonding areas1022in the upper and lower rows are staggered or offset from each other.

On this basis, as shown inFIG.5, in the second direction Y, the two first electrode bonding areas1060of the same bonding group102face each other and are arranged at intervals, and the two second electrode bonding areas1062of the same bonding group102face each other and are arranged at intervals. A gap is defined between two rows of the bonding groups102of the same combination unit104. The orthographic projection of the output terminal of the pixel driving circuit103projected on the first surface100(as shown in the dotted box labeled108inFIG.5) is located in the gap and between two first electrode bonding areas1060of the same bonding group102. This design may reduce the difficulty of wiring and producing process. In some embodiments, as shown inFIG.5, in the second direction Y, an intermediate region105is defined between the two first electrode bonding areas1060of the same bonding group102. The orthographic projection of the output terminal of the pixel driving circuit103projected on the first surface100(as shown in the dotted box labeled108inFIG.5) and the intermediate region105are arranged at intervals in the first direction X.

In some embodiments, as shown inFIG.5andFIG.6,FIG.6is a schematic top view of the pixel driving circuit and associated wiring shown inFIG.5according to an embodiment of the present disclosure. In some embodiments, the driving backplane10includes a thin film transistor layer and an insulating layer disposed above the thin film transistor layer. The pixel driving circuits103are located in the thin film transistor layer, and a surface of the insulating layer facing away from the thin film transistor layer forms the first surface100. The first electrode bonding areas1060and the second electrode bonding areas1062may be exposed from the first surface100of the driving backplane10for bonding with the sub-pixels120. In this case, a position of the insulating layer corresponding to the output terminal of the pixel driving circuit103may define a conductive hole (i.e., the position indicated by the dotted line box labeled108inFIG.5andFIG.6). The conductive hole is further electrically connected to the two first electrodes bonding area1060on opposite sides of the conductive hole through the metal wirings. It may be seen fromFIG.5andFIG.6that, the output terminals of the pixel driving circuits103are arranged at intervals along the second direction Y, so that the pixel driving circuits103may be repeatedly arranged in the second direction Y, thereby reducing the layout difficulty of the pixel driving circuits103.

As shown inFIG.5, the pixel unit inFIG.5includes three adjacent sub-pixels120(a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B). The combination unit104includes three bonding groups102electrically connected to the sub-pixels120in the corresponding pixel unit. Three normal bonding areas1020of the combination unit104are arranged alternately up and down, and three redundant bonding areas1022of the combination unit104are arranged alternately up and down. In some embodiments, the display panel1includes multiple repeating units106. In the second direction Y, two adjacent combination units104constitute one repeating unit106. A plurality of normal bonding areas1020of the repeating unit106are arranged alternately up and down. A plurality of redundant bonding areas1022of the repeating unit106are arranged alternately up and down. The design of the repeating units106may reduce the complexity for producing the display panel1.

Of course, in other embodiments, the combination units104inFIG.5may also be arranged in other manner. For example, as shown inFIG.7,FIG.7is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. The pixel unit shown inFIG.7includes three adjacent sub-pixels120(a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B). The combination unit104includes three bonding groups102electrically connected to the sub-pixels120in the corresponding pixel unit. In the first direction X, the combination units104of at least one pair of combination units104adjacent to each other are arranged axially symmetrically. At least parts of the normal bonding areas1020, which correspond to the sub-pixels with the same emitting color, of two adjacent combination units104arranged axially symmetrically, are arranged adjacent to each other. This design may make parts of the two sub-pixels120in the normal bonding areas1020in two bonding groups102adjacent to each other in the first direction X may be transferred and bonded at the same time or simultaneously, so as to improve the bonding efficiency. Besides, the two sub-pixels will not be affected by the sub-pixels120on the remaining normal bonding areas1020during the bonding transfer process, so as to improve the yield of bonding. For example, as shown inFIG.7, two adjacent blue sub-pixels having no redundant bonding area1022disposed there between in the first direction X may be transferred and bonded at the same time. The two blue sub-pixels will not be squeezed or collided by adjacent red sub-pixels or green sub-pixels during the bonding process due to the redundant bonding areas1022surrounding the two blue sub-pixels.

In some embodiments, as shown inFIG.7, a third distance D3between two adjacent normal bonding areas1020from two adjacent combination units104in the first direction X is shorter than a fourth distance D4between another two adjacent normal bonding areas1020of the same combination unit104. This design may increase the arrangement density of the pixels to improve the display effect. In some embodiments, the third distance D3and the fourth distance D4may be the distance between edges of two adjacent normal bonding areas1020. Or, the third distance D3and the fourth distance D4may be the distance between center points of two adjacent normal bonding areas1020.

In some embodiments, as shown inFIG.7, the display panel1includes a plurality of repeating units106, and four combination units104adjacent to each other in the first direction X and the second direction Y (the four adjacent combination units104in the up, down, left, and right directions) constitute one repeating unit106. The normal bonding areas1020and the redundant bonding areas1022in the same row of the repeating unit106are arranged alternately in the second direction Y. This design may reduce the difficulty of producing process.

In the above embodiments, the normal bonding areas1020and the redundant bonding areas1022of the same combination unit104are arranged alternately up and down. In other embodiments, the normal bonding areas1020may be arranged in a row and the redundant bonding areas1022of the same combination unit104may be arranged in another row.

In an application scenario, as shown inFIG.8,FIG.8is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. A plurality of adjacent sub-pixels120constitute one pixel unit122, and a plurality of bonding groups102electrically connected to the pixel unit122constitute one combination unit104. The normal bonding areas1020and the redundant bonding areas1022of the same bonding group102are arranged along the first direction X. A plurality of normal bonding areas1020of the combination unit104are adjacently arranged in the same row along the second direction Y. A plurality of redundant bonding areas1022of the combination unit104are adjacently arranged in another same row along the second direction Y. A row of redundant bonding areas1022is provided between two rows of normal bonding areas1020of two adjacent combination units104in each of the first direction X and the second direction Y. The structural is relatively simple and the producing process is easy to implement. The transfer head may pick up three sub-pixels120bonded to the same combination unit104at the same time or simultaneously during the process of bonding the sub-pixels120to the normal bonding area1020, so as to improve the bonding efficiency.

On this basis, as shown inFIG.8, the driving backplane10includes a plurality of pixel driving circuits103, and the normal bonding area1020and the redundant bonding area1022of the same bonding group102may be electrically connected to output terminals of the same pixel driving circuit103. In some embodiments, in the first direction X, two first electrode bonding areas1060of the same bonding group102face each other and are arranged at intervals. The two first electrode bonding areas1060of the same bonding group102are located between two second electrode bonding areas1062. That is, in the first direction X, the first electrode bonding areas1060and the second electrode bonding areas1062of the same bonding group102are sequentially arranged at intervals in the following manner: the second electrode bonding area1062, the first electrode bonding area1060, the first electrode bonding area1060, and the second electrode bonding area1062. In this case, an orthographic projection of the output terminal of the pixel driving circuit103projected on the first surface100in the first direction X (as shown by the dotted box labeled108inFIG.8) is located between the two first electrode bonding areas1060. The above structure is relatively simple and the producing process is easy to implement. In this case, the corresponding pixel driving circuit103and associated wiring inFIG.8may be depicted as shown inFIG.3.

In addition, the pixel unit122inFIG.8includes three adjacent sub-pixels120(a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B). The combination unit104includes three bonding groups102electrically connected to sub-pixels120in the corresponding pixel unit122. Three normal bonding areas1020of the combination unit104are arranged in the same row. Three redundant bonding areas1022of the combination unit104are arranged in another same row. The display panel includes multiple repeating units106. In the second direction Y, two adjacent combination units104constitute one repeating unit106, and two rows of the normal bonding areas1020of two combination units104of the repeating unit106are arranged alternately up and down. The design of the repeating unit106may reduce the complexity for producing the display panel.

In some embodiments, as shown inFIG.8, a number of every two adjacent pixel units122arranged in the oblique direction is greater than a number of every two adjacent pixel units122arranged in the same row in the first direction X or the second direction Y. The oblique direction is intersected with the first direction X and the second direction Y. All the sub-pixels120in each pixel unit122in two adjacent pixel units122are arranged in the same row along the first direction X or the second direction Y. The sub-pixels120in a certain pixel unit122which not arranged in the same row are not included in a counting range. For example, takingFIG.8as an example, a pixel unit122corresponding to the combination unit104in an upper left corner is adjacent to a pixel unit122corresponding to the combination unit104in an upper right corner in the first oblique direction, and the pixel unit122corresponding to the combination unit104in the upper left corner is adjacent to a pixel unit122corresponding to the combination unit104in a lower right corner in the second oblique direction. The first oblique direction is different from the second oblique direction, but both the first oblique direction and the second oblique direction are intersected with the first direction X and the second direction Y. The above design may make the distance between two adjacent pixel units122as large as possible.

Of course, in other embodiments, the combination units104inFIG.8may also be arranged in other manner. For example, as shown inFIG.9,FIG.9is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. The pixel unit122inFIG.9includes three adjacent sub-pixels120(a red sub-pixel R, a green sub-pixel G and a blue sub-pixel B). The combination unit104includes three bonding groups102electrically connected to the sub-pixels120in the pixel unit122. Three normal bonding areas1020of the combination unit104are arranged in the same row, and three redundant bonding areas1022of the combination unit104are arranged in another same row. In the first direction X, the combination units104of at least one pair of combination units104adjacent to each other are arranged axially symmetrically. The normal bonding areas1020, which correspond to the sub-pixels with the same emitting color, of two adjacent combination units104arranged axially symmetrically, face each other.

In some embodiments, as shown inFIG.9, the display panel1includes a plurality of repeating units106, and four combination units104adjacent to each other in the first direction X and the second direction Y (the four adjacent combination units104in the up, down, left, and right directions) constitute one repeating unit106. In the second direction Y, the arrangement of the redundant bonding areas1022and the normal bonding areas1020in two adjacent combination units104of the repeating unit106is reversed. This design may reduce the difficulty of the producing process. In another application scenario, as shown inFIG.10,FIG.10is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. The difference between the embodiment shown inFIG.10and the embodiment shown inFIG.8is that a row of redundant bonding areas1022is provided between two rows of normal bonding areas1020of two adjacent combination units104in the first direction X, and two rows of normal bonding areas1020of two adjacent combination units104in the direction Y are arranged adjacently, that is, on the same straight line. The structural is relatively simple and the producing process is easy to realize.

In addition, the pixel unit122inFIG.10includes three adjacent sub-pixels120(a red sub-pixel R, a green sub-pixel G, and a blue sub-pixel B). The combination unit104includes three bonding groups102electrically connected to sub-pixels120in the corresponding pixel unit122. In this case, one combination unit104constitutes one repeating unit106. The design of the repeating unit106may reduce the complexity for producing the display panel.

Of course, in other embodiments, the combination units104inFIG.10may also be arranged in other manner. For example, as shown inFIG.11,FIG.11is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. In the first direction X, the combination units104of at least one pair of combination units104adjacent to each other are arranged axially symmetrically. The normal bonding areas1020of two adjacent combination units104arranged axially symmetrically, which correspond to the sub-pixels120with the same emitting color, are arranged adjacent to each other. Further, the display panel1includes a plurality of repeating units106, and two adjacent combination units104arranged in the first direction X constitute one repeating unit106.

As shown inFIG.2,FIG.4,FIG.5,FIG.7, orFIG.8, the second electrode bonding areas1062of all the normal bonding areas1020and the redundant bonding areas1022in the same row in the second direction Y are located on the same straight line, and all the second electrode bonding areas1062on the same straight line are electrically connected to a same power supply voltage line101. This design may save wiring areas of the pixel driving circuits103, and is suitable for high PPI or closely-arranged display pixel arrangement scenarios.

In some embodiments, as shown inFIG.2,FIG.4,FIG.5,FIG.7, orFIG.8, the power supply voltage line101is located between two rows of the second electrode bonding areas1062in the first direction X, and the power supply voltage line101is electrically connected to the two rows of the second electrode bonding areas1062adjacent to the power supply voltage line101. This design may further save the wiring areas of the pixel driving circuits103, and is suitable for high PPI or closely-arranged display pixel arrangement scenarios.

In some embodiments, as shown inFIG.2,FIG.4,FIG.5,FIG.7, orFIG.8, the power supply voltage line101may provide a VSS low power supply voltage when the second electrode bonding areas1062electrically connected to the power supply voltage line101are configured to be bonded to N-electrodes. Of course, the power supply voltage line101may provide a VDD high power supply voltage when the second electrode bonding areas1062electrically connected to the power supply voltage line101are configured to be bonded to P-electrodes, which are not limited in some embodiments of the present disclosure.

In addition, as shown inFIG.2, each sub-pixel120defines a first axis of symmetry L1. An extension direction of the first axis of symmetry L1is substantially parallel to the first direction X. In other embodiments, the extending direction of the first axis of symmetry L1of the sub-pixel120may also be intersected with the first direction X, and an intersection angle between the extending direction of the first axis of symmetry L1and the first direction X may be approximately 30 degrees, approximately 45 degrees, or approximately 90 degrees.

For example, as shown inFIG.12,FIG.12is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. As shown inFIG.12, the first axis of symmetry L1of each sub-pixel120is intersected with the first direction X, and the first axis of symmetry L1of all the sub-pixels120are arranged substantially parallel to each other. In this case, positions of the first electrode bonding areas1060and the second electrode bonding areas1062in the redundant bonding areas1022and the normal bonding areas1020shown inFIG.2will be rotated to positions inFIG.10in accordance with positions of the sub-pixels120. The above design is relatively simple and easy to be implemented.

For another example, as shown inFIG.13,FIG.13is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. As shown inFIG.13, the first axis of symmetry L1of each sub-pixel120is intersected with the first direction X, and the extending direction of the first axis of symmetry L1of each of a first row of sub-pixels120is intersected with an extending direction of the first axis of symmetry L1of each of a second row of sub-pixels120adjacent to the first row in the first direction X. In some embodiments, an intersection angle between the first direction X and the extending direction of the first symmetry axis L1of each of the first row of sub-pixels120is substantially equal to an intersection angle between the first direction X and the extending direction of the first symmetry axis L1of each of the second row of sub-pixels120adjacent to the first row in the first direction X. The above design is relatively simple and easy to implement.

As shown inFIG.2, the orthographic projection of each sub-pixel120projected on the first surface is substantially in shape of a rectangle. Or, as shown inFIG.14,FIG.14is a partial top view of the display panel shown inFIG.1before a defective pixel is repaired according to another embodiment of the present disclosure. The orthographic projection of each sub-pixel120projected on the first surface is substantially in shape of a rounded rectangle. In other embodiments, the orthographic projection of each sub-pixel120projected on the first surface may also be a circular, elliptical, triangular, trapezoidal, pentagonal, hexagonal, or other special-shaped structures, which is not limited herein. The sub-pixels120of the above shape are easy to produce. As shown inFIG.14, a distance P1between the center points of the sub-pixels120in the two adjacent normal bonding areas1020is greater than a distance P2between the center point of the sub-pixel120in the normal bonding area1020and the center point of the sub-pixel120in the redundant bonding area1022adjacent to the normal bonding areas1020.

As shown inFIG.15,FIG.15is a schematic flow chart of a preparation method of a display panel according to an embodiment of the present disclosure. The preparation method may include operations executed by the following blocks.

At block101, a driving backplane is provided. A first surface of the driving backplane is provided with a plurality of normal bonding areas and a plurality of redundant bonding areas. A distance between every two of the plurality of normal bonding areas, which are adjacent to each other, is defined as a first distance. A distance between each normal bonding area and a corresponding one of the redundant bonding areas, which is adjacent to the each normal bonding area, is defined as a second distance. At least one of the first distances is greater than at least one of the second distances. At least one of the plurality of normal bonding areas and at least one of the plurality of redundant bonding areas adjacent to the at least one of the plurality of normal bonding areas constitute one bonding group.

In some embodiments, the structure of the driving backplane may refer to any of the foregoing embodiments, and details are not repeated here.

At block102, a plurality of sub-pixels are disposed in the normal bonding areas of the driving backplane.

In some embodiments, a plurality of sub-pixels may be simultaneously transferred to the normal bonding areas at corresponding positions by a mass transfer device, and the sub-pixels may be bonded and connected to the normal bonding areas by substances such as solder. In some embodiments, the diagram corresponding to the block102may refer toFIG.2.

At block103, a patched sub-pixel with the same emitting color as a defective sub-pixel is introduced on or bonded to the redundant bonding area, in response to the sub-pixel bonded to the normal bonding area of the same bonding group being determined to be the defective sub-pixel.

In some embodiments, after the block102, a lighting test may be performed on the sub-pixels in the normal bonding areas by the driving backplane. If the brightness of one sub-pixel is abnormal (including the situations that the brightness is lower than a first threshold or the brightness exceeds a second threshold), the sub-pixel is determined as a defective sub-pixel. The defective sub-pixel may be removed from the normal bonding area by means of laser, etc., and the patched sub-pixel with the same emitting color may be provided in the redundant bonding area of the same bonding group to replace the sub-pixel in the original normal bonding area. For example, as shown inFIG.16,FIG.16is a schematic structural view of a display panel shown inFIG.2after being repaired according to an embodiment of the present disclosure. Assuming that a green sub-pixel G in an upper left portion ofFIG.2is found to be a defective sub-pixel after the lighting test, after the defective sub-pixel is removed, a patched sub-pixel120ais introduced in or bonded to the corresponding redundant bonding area, and the patched sub-pixel120amay emit green light.

Or, if the defective sub-pixel is a disconnected sub-pixel, the defective sub-pixel may be reserved, and the patched sub-pixel with the same emitting color may be arranged in the redundant bonding area of the same bonding group to replace the defective sub-pixel in the normal bonding area. For example, as shown inFIG.17,FIG.17is a schematic structural view of a display panel shown inFIG.2after being repaired according to another embodiment of the present disclosure. Assuming that the green sub-pixel G in the upper left portion ofFIG.2is found to be a defective sub-pixel after the lighting test and the defective sub-pixel is a disconnected sub-pixel and cannot emit green light normally, the defective sub-pixel is reserved, a patched sub-pixel120ais introduced in or bonded to the corresponding redundant bonding area, and the patched sub-pixel120amay emit green light.

The above description is only embodiments of the present disclosure, and does not limit the scope of the present disclosure. Any equivalent structural transformations or equivalent process transformations made by using the specification and the drawings of the present disclosure, or directly or indirectly apply the specification and the drawings of the present disclosure to other related technical fields, are all included within the protection scope of the present disclosure.