Display substrate, display apparatus and mask

Abstract

Provided is a display substrate. The display substrate comprises: a base substrate; and a plurality of sub-pixels, which are located on the base substrate, the plurality of sub-pixels comprising a plurality of first sub-pixel columns and a plurality of second sub-pixel columns, the plurality of first sub-pixel columns and the plurality of second sub-pixel columns being alternately arranged in a first direction, each first sub-pixel column comprising a plurality of first sub-pixels and a plurality of second sub-pixels, the plurality of first sub-pixels and the plurality of second sub-pixels being alternately arranged at intervals in a second direction, each second sub-pixel column comprising a plurality of third sub-pixels, and the plurality of third sub-pixels being arranged at intervals in the second direction, wherein each first sub-pixel has a first pixel opening, each second sub-pixel has a second pixel opening, each third sub-pixel has a third pixel opening, the area of the orthographic projection of the third pixel opening on the base substrate is smaller than the area of the orthographic projection of the first pixel opening on the base substrate, and the area of the orthographic projection of the third pixel opening on the base substrate is smaller than the area of the orthographic projection of the second pixel opening on the base substrate.

Description

Display substrate, display device and mask Technical Field

[0001] This disclosure relates to the field of display technology, and in particular to a display substrate, display device, and mask. Background Technology

[0002] Organic light-emitting diode (OLED) display technology is a technology that uses organic semiconductor materials to emit light when driven by an electric current to achieve display. OLED display devices have advantages such as being lightweight, thin, low-power, high-contrast, and capable of flexible displays. Therefore, OLED display technology is considered a promising next-generation display technology. Improving the aperture ratio of OLED display substrates is one of the key research topics for display product developers.

[0003] The information disclosed in this section is only for understanding the background of the inventive concept of this disclosure, and therefore may include information that does not constitute prior art. Summary of the Invention

[0004] In one aspect, a display substrate is provided, comprising:

[0005] Substrate;

[0006] Multiple sub-pixels are located on the substrate. The multiple sub-pixels include multiple first sub-pixel columns and multiple second sub-pixel columns. The multiple first sub-pixel columns and multiple second sub-pixel columns are alternately arranged along a first direction. The first sub-pixel columns include multiple first sub-pixels and multiple second sub-pixels. The multiple first sub-pixels and multiple second sub-pixels are alternately arranged and spaced apart along a second direction. The first direction and the second direction intersect. The second sub-pixel columns include multiple third sub-pixels. The multiple third sub-pixels are spaced apart along the second direction.

[0007] Wherein, the first sub-pixel has a first pixel opening, the second sub-pixel has a second pixel opening, and the third sub-pixel has a third pixel opening. The area of ​​the orthographic projection of the third pixel opening on the substrate is smaller than the area of ​​the orthographic projection of the first pixel opening on the substrate, and the area of ​​the orthographic projection of the third pixel opening on the substrate is smaller than the area of ​​the orthographic projection of the second pixel opening on the substrate.

[0008] According to some exemplary embodiments, the size of the third pixel opening along the first direction is smaller than the size of the third pixel opening along the second direction.

[0009] According to some exemplary embodiments, the size of the third pixel opening along the first direction is less than or equal to half the size of the third pixel opening along the second direction.

[0010] According to some exemplary embodiments, the size of the third pixel opening along the first direction is smaller than the size of the first pixel opening along the first direction; and / or,

[0011] The size of the third pixel opening along the first direction is smaller than the size of the second pixel opening along the first direction.

[0012] According to some exemplary embodiments, the size of the third pixel opening along the first direction is less than half the size of the first pixel opening along the first direction; and / or,

[0013] The size of the third pixel opening along the first direction is less than half the size of the second pixel opening along the first direction.

[0014] According to some exemplary embodiments, the size of the third pixel opening along the second direction is larger than the size of the first pixel opening along the second direction; and / or,

[0015] The size of the third pixel opening along the second direction is larger than the size of the second pixel opening along the second direction.

[0016] According to some exemplary embodiments, the size of the first pixel opening along the first direction is greater than or equal to the size of the first pixel opening along the second direction; and / or,

[0017] The size of the second pixel opening along the first direction is greater than or equal to the size of the second pixel opening along the second direction.

[0018] According to some exemplary embodiments, the distance between two adjacent third pixel openings along the second direction is a first distance, and the distance between the first pixel opening and the adjacent second pixel opening along the second direction is a second distance, wherein the second distance is less than half of the first distance.

[0019] According to some exemplary embodiments, the third sub-pixel is a red sub-pixel, the first sub-pixel is a green sub-pixel, and the second sub-pixel is a blue sub-pixel.

[0020] According to some exemplary embodiments, the ratio of the opening area of ​​the first pixel to the opening area of ​​the third pixel is greater than 1 and less than or equal to 4; and / or,

[0021] The ratio of the opening area of ​​the second pixel to the opening area of ​​the third pixel is greater than or equal to 1.5 and less than or equal to 5.

[0022] According to some exemplary embodiments, in the first sub-pixel and the second sub-pixel adjacent along the second direction and the third sub-pixel adjacent along the first direction, the geometric center of the orthographic projection of the opening of the first pixel on the substrate is the first center, the geometric center of the orthographic projection of the opening of the second pixel on the substrate is the second center, and the geometric center of the orthographic projection of the opening of the third pixel on the substrate is the third center. The third center is located on the side closer to the second center than the midpoint of the line connecting the first center and the second center.

[0023] According to some exemplary embodiments, the side of the third pixel opening away from the first sub-pixel along the second direction is substantially flush with the side of the second pixel opening away from the first sub-pixel along the first direction.

[0024] According to some exemplary embodiments, in the first sub-pixel and the second sub-pixel adjacent along the second direction and the third sub-pixel adjacent along the first direction, the geometric center of the orthographic projection of the opening of the first pixel on the substrate is the first center, the geometric center of the orthographic projection of the opening of the second pixel on the substrate is the second center, and the geometric center of the orthographic projection of the opening of the third pixel on the substrate is the third center. The third center is located on the side closer to the first center than the midpoint of the line connecting the first center and the second center.

[0025] According to some exemplary embodiments, the side of the third pixel opening away from the second sub-pixel along the second direction is substantially flush with the side of the first pixel opening away from the second sub-pixel along the first direction.

[0026] According to some exemplary embodiments, the display substrate includes a driving circuit layer on the substrate and a light-emitting device layer on the side of the driving circuit layer away from the substrate. The driving circuit layer includes a source / drain metal layer closest to the light-emitting device layer. The source / drain metal layer includes a power signal line extending along the second direction. The orthographic projection of the third pixel opening on the substrate is located within the orthographic projection of the power signal line on the substrate.

[0027] According to some exemplary embodiments, the display substrate includes a driving circuit layer located on the substrate and a light-emitting device layer located on the side of the driving circuit layer away from the substrate. The driving circuit layer includes a source / drain metal layer closest to the light-emitting device layer, and the source / drain metal layer includes data signal lines extending along the second direction; and

[0028] The orthographic projection of the third pixel opening on the substrate overlaps with the orthographic projection of the data signal line on the substrate, and the geometric center of the orthographic projection of the third pixel opening on the substrate is located within the orthographic projection of the data signal line on the substrate.

[0029] According to some exemplary embodiments, the display substrate includes a driving circuit layer on the substrate and a light-emitting device layer on the side of the driving circuit layer away from the substrate. The driving circuit layer includes a source / drain metal layer closest to the light-emitting device layer. The source / drain metal layer includes a data signal line extending along the second direction and a blank trace extending along the second direction.

[0030] The first portion of the orthographic projection of the third pixel opening on the substrate overlaps with the orthographic projection of the data signal line on the substrate, and the second portion of the orthographic projection of the third pixel opening on the substrate overlaps with the orthographic projection of the blank trace on the substrate; and

[0031] The first part and the second part are located on both sides of the geometric center of the orthographic projection of the third pixel opening on the substrate along the first direction.

[0032] According to some exemplary embodiments, the display substrate includes a driving circuit layer located on the substrate and a light-emitting device layer located on the side of the driving circuit layer away from the substrate. The driving circuit layer includes a source / drain metal layer closest to the light-emitting device layer. The source / drain metal layer includes a plurality of signal traces, which extend along a second direction and are arranged along a first direction.

[0033] The orthographic projection of the third pixel opening on the substrate is located between the orthographic projections of the two adjacent signal traces on the substrate.

[0034] In another aspect, a display device is provided, the display device comprising a display substrate as described in any of the preceding claims.

[0035] In another aspect, a photomask is provided for fabricating a display substrate as described in any of the preceding claims, the photomask comprising:

[0036] A first sub-mask is used to create the first sub-pixel, and the first sub-mask includes a plurality of first openings arranged in an array.

[0037] A second sub-mask, used to fabricate the second sub-pixel, the second sub-mask including a plurality of second openings arranged in an array; and

[0038] A third sub-mask is used to create the third sub-pixel. The third sub-mask includes a plurality of third openings arranged in an array. The area of ​​the third opening is smaller than the area of ​​the first opening and the area of ​​the third opening is smaller than the area of ​​the second opening. Attached Figure Description

[0039] Other objects and advantages of this disclosure will become apparent from the following description of the disclosure with reference to the accompanying drawings, and will help to provide a comprehensive understanding of the disclosure.

[0040] Figures 1A and 1B schematically illustrate pixel layout diagrams of display substrates according to some embodiments of the present disclosure.

[0041] Figures 2A and 2B schematically illustrate pixel layout diagrams of display substrates according to some embodiments of the present disclosure.

[0042] Figure 3A schematically shows a plan view of a mask for manufacturing blue sub-pixels of a display substrate according to some embodiments of the present disclosure.

[0043] Figure 3B schematically shows a cross-sectional view taken along line AA' in Figure 3A.

[0044] Figures 4A-4B schematically illustrate plan views of a first pixel delimiter in a display substrate according to some embodiments of the present disclosure.

[0045] Figure 5 schematically illustrates the pixel arrangement of a display substrate according to some embodiments of the present disclosure.

[0046] Figure 6 schematically shows a cross-sectional view taken along line BB' in Figure 5.

[0047] Figure 7 schematically illustrates a pixel arrangement diagram of a display substrate according to some embodiments of the present disclosure.

[0048] Figure 8 schematically illustrates a pixel arrangement diagram of a display substrate according to some embodiments of the present disclosure.

[0049] Figure 9 schematically shows a plan view of a third pixel aperture and driving circuit layer combination of some display substrates according to embodiments of the present disclosure.

[0050] Figure 10 schematically shows a plan view of a third pixel aperture and driving circuit layer combination of some display substrates according to embodiments of the present disclosure.

[0051] Figure 11 schematically shows a plan view of a third pixel aperture and driving circuit layer combination of some display substrates according to embodiments of the present disclosure.

[0052] Figure 12 schematically shows a plan view of a third pixel aperture and driving circuit layer combination of some display substrates according to embodiments of the present disclosure.

[0053] Figures 13A-13C schematically illustrate plan views of some mask plates according to embodiments of the present disclosure.

[0054] It should be noted that, for clarity, the dimensions of layers, structures, or regions in the accompanying drawings used to describe embodiments of this disclosure may be enlarged or reduced; that is, these drawings are not drawn to actual scale. Detailed Implementation

[0055] In the following description, numerous specific details are set forth for illustrative purposes to provide a comprehensive understanding of various exemplary embodiments. However, it will be apparent that various exemplary embodiments may be implemented without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and apparatuses are shown in block diagram form to avoid unnecessarily obscuring the various exemplary embodiments. Furthermore, the various exemplary embodiments may be different, but not necessarily exclusive. For example, specific shapes, configurations, and characteristics of exemplary embodiments may be used or implemented in another exemplary embodiment without departing from the inventive concept.

[0056] In the accompanying drawings, the dimensions and relative dimensions of the elements may be enlarged for clarity and / or descriptive purposes. Thus, the dimensions and relative dimensions of the individual elements are not necessarily limited to those shown in the drawings. When exemplary embodiments can be implemented differently, the specific process sequence may be performed differently than the order described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of description. Furthermore, the same reference numerals denote the same elements.

[0057] When an element is described as being "on" another element, "connected to" another element, or "attached to" another element, the element may be directly on, directly connected to, or directly attached to the other element, or there may be intermediate elements present. However, when an element is described as being "directly on" another element, "directly connected to" another element, or "directly attached to" another element, there are no intermediate elements. Other terms and / or expressions used to describe relationships between elements should be interpreted in a similar manner, such as "between" versus "directly between," "adjacent" versus "directly adjacent," or "on" versus "directly on," etc. Furthermore, the term "connection" can refer to a physical connection, an electrical connection, a communication connection, and / or a fluid connection. Additionally, the X-axis, Y-axis, and Z-axis are not limited to the three axes of a Cartesian coordinate system and can be interpreted in a broader sense. For example, the X-axis, Y-axis, and Z-axis may be perpendicular to each other, or may represent different directions that are not perpendicular to each other. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” can be interpreted as only X, only Y, only Z, or any combination of two or more of X, Y, and Z such as XYZ, XY, YZ, and XZ. As used herein, the term “and / or” includes any and all combinations of one or more of the listed related items.

[0058] It should be understood that although the terms first, second, etc., may be used herein to describe different elements, these elements should not be limited by these terms. These terms are merely used to distinguish one element from another. For example, without departing from the scope of the exemplary embodiments, a first element may be named a second element, and similarly, a second element may be named a first element.

[0059] Figures 1A and 1B schematically illustrate pixel arrangement diagrams of a display substrate according to some embodiments of the present disclosure, wherein Figure 1A illustrates sub-pixels in the display substrate and Figure 1B illustrates sub-pixels in the display substrate and pixel delimiting layers located between sub-pixels.

[0060] Referring to Figure 1A, in this display substrate, red sub-pixels R and green sub-pixels G are arranged alternately along the second direction Y, and multiple blue sub-pixels B are arranged at intervals along the second direction Y. That is, red sub-pixels R and green sub-pixels G are arranged in the same column, and multiple blue sub-pixels B are arranged in the same column. Furthermore, considering the differences in efficiency and lifespan of the red light-emitting devices in red sub-pixels R, the green light-emitting devices in green sub-pixels G, and the blue light-emitting devices in blue sub-pixels B, the light-emitting areas of sub-pixels of different colors are set in a certain proportion according to the performance differences of the light-emitting devices of different colors. For example, the light-emitting area of ​​blue sub-pixels B is the largest, the light-emitting area of ​​green sub-pixels G is the second largest, and the light-emitting area of ​​red sub-pixels R is the smallest.

[0061] Referring to Figures 1A and 1B, the display substrate also includes a pixel defining layer (PDL). The pixel defining layer (PDL) has a pixel opening (PK). The area where the pixel opening (PK) is located can be equivalent to the light-emitting area of ​​the sub-pixel. Therefore, the width of the pixel defining layer (PDL) between two adjacent pixel openings (PK) will have a significant impact on the aperture ratio of the display panel.

[0062] Figures 2A and 2B schematically illustrate pixel arrangement diagrams of a display substrate according to some embodiments of the present disclosure, wherein Figure 2A illustrates sub-pixels in the display substrate, and Figure 2B illustrates sub-pixels in the display substrate and pixel defining layers located between sub-pixels. Figure 3A schematically illustrates a plan view of a mask for manufacturing blue sub-pixels of a display substrate according to some embodiments of the present disclosure.

[0063] In the structure shown in Figure 1B, the width of the pixel delimiting layer (PDL) is basically equal everywhere. However, the inventors discovered that because the blue sub-pixels B are located in the same column, and referring to Figures 1B and 3A, the multiple openings KK in the fine metal mask (FMM) used to vapor-deposit the light-emitting layer of the blue sub-pixels B are arranged in the same column along the second direction Y. This results in the spacing between adjacent blue sub-pixels B along the second direction in the actual formed display substrate being larger than the spacing shown in Figure 1B. Referring to Figures 1A to 2B, in the actual formed display substrates shown in Figures 2A and 2B, the spacing between adjacent blue sub-pixels B along the second direction is larger than the spacing shown in Figures 1A and 1B.

[0064] Referring to Figures 2A, 2B, and 3A, in a column of openings KK, the portion between adjacent openings KK is a rib. The presence of this rib causes the spacing between adjacent blue sub-pixels B along the second direction Y to be larger than the spacing between other adjacent sub-pixels. In other words, the width of the pixel delimiting layer (PDL) between adjacent blue sub-pixels B along the second direction Y needs to be set larger, which will lead to a decrease in the aperture ratio of the display substrate.

[0065] To more clearly illustrate the problem that the ribs between adjacent openings KK cause a decrease in the aperture ratio of the display substrate, Figure 2B illustrates the rib region RA. The position of the rib region RA and its dimension along the second direction Y are basically the same as the position of the ribs Rib on the FMM used during evaporation and its dimension along the second direction Y. The rib region RA represents the area of ​​aperture ratio loss caused by the presence of ribs Rib on the FMM used during evaporation.

[0066] It should be noted that the rib region RA is not a region of practical significance in the display substrate. A pixel definition layer (PDL) is also provided in the rib region RA, and the pixel definition layer (PDL) in the rib region RA is connected to the pixel definition layer (PDL) in other regions to form an integral structure.

[0067] To further improve the aperture ratio of the display substrate, a "n in 1" design for the blue sub-pixels B can be adopted. That is, the light-emitting layers of n adjacent blue sub-pixels B along the second direction Y are deposited together through one opening in the FMM. This eliminates at least a portion of the ribs on the FMM, thereby effectively improving the aperture ratio.

[0068] In practice, the “n in 1” design can be implemented in a “2 in 1” or “4 in 1” manner. Alternatively, the light-emitting layer 420 of all blue sub-pixels B in a column can be vapor-deposited through a slit-type opening in the FMM (i.e., using Slit FMM vapor deposition). However, the inventors have found that this method can lead to uneven spacing between blue sub-pixels B in the same column, thus affecting the display effect.

[0069] Figures 4A-4B schematically illustrate plan views of a first pixel delimiter in a display substrate according to some embodiments of the present disclosure.

[0070] In order to further improve the aperture ratio of the display substrate while ensuring the display effect, the inventors conducted more in-depth research.

[0071] Referring to FIG2B, the pixel defining layer PDL in the display substrate can be divided into a first pixel defining portion 110 located outside the rib region RA and a second pixel defining portion 120 located inside the rib region RA.

[0072] Referring to Figures 4A and 4B, adjacent red sub-pixels R, green sub-pixels G, and blue sub-pixels B constitute a pixel unit PX. The first pixel defining portion 110 can be divided into a first sub-portion 111 located in the area surrounding the pixel unit PX (the area between adjacent pixel units PX) and a second sub-portion 112 located in the sub-pixel spacing area within the pixel unit PX. Considering that adjacent pixel units PX must be spaced at a predetermined distance, the aperture ratio loss caused by the first sub-portion 111 around the pixel unit PX is unavoidable. Reducing the aperture ratio loss caused by the first sub-portion 111 requires changing the arrangement of the pixel units PX, which carries a high risk of deteriorating the display effect. Regarding the second sub-portion 112 located within the pixel unit PX, considering that a pixel unit PX divided into three sub-pixels (R, G, B) will have at least two boundaries, under this structure, the size of the second sub-portion 112 along the second direction Y is immutable, and the size along the first direction X is limited by the proportion and cannot be adjusted, making it difficult to further reduce the area of ​​the second sub-portion 112.

[0073] It should be noted that Figures 4A and 4B are shown in the case of excluding the second pixel definition portion, in order to provide a clearer explanation of the first pixel definition portion 110.

[0074] Referring back to FIG2B, the area of ​​the second pixel defining portion 120 located in the rib region RA can be determined based on the height b along the second direction Y and the width a along the first direction X of the second pixel defining portion 120.

[0075] Figure 3B schematically shows a cross-sectional view taken along line AA' in Figure 3A.

[0076] Referring to Figures 2B, 3A, and 3B, the height b of the second pixel defining portion 120 depends on the height RH1 of the rib Rib of the mask used for vapor deposition to form the blue sub-pixel B. The height RH1 of the rib Rib is negatively correlated with the shadow thickness SH of the mask at the rib Rib. When the mask used is fixed, the height RH1 of the rib is fixed, and the height b of the second pixel defining portion 120 is also fixed. Therefore, the area of ​​the second pixel defining portion 120 can be reduced by decreasing the width a of the second pixel defining portion 120, thereby increasing the aperture ratio of the display substrate. The width a of the second pixel defining portion 120 depends on the width of the blue sub-pixel B along the first direction X. However, if the width of the blue sub-pixel B is narrowed, the pixel aperture area of ​​the blue sub-pixel B will decrease, thus affecting the display effect. In order to reduce the aperture ratio loss caused by the second pixel defining portion 120 without affecting the display effect, the inventors discovered that other sub-pixels with smaller areas can be arranged in the same column along the second direction.

[0077] It should be noted that the openings in the mask can be obtained by etching the two opposite sides of the mask, so that the mask has a sharp corner structure at the opening. During the vapor deposition, one side (the upper surface shown in Figure 3B) faces the substrate to be vapor deposited. The distance between the tip of the sharp corner structure and the side of the mask facing the substrate to be vapor deposited along the thickness direction of the mask is the shadow thickness SH.

[0078] Figure 5 schematically illustrates a pixel arrangement diagram of a display substrate according to some embodiments of the present disclosure. Figure 6 schematically illustrates a cross-sectional view taken along line BB' in Figure 5.

[0079] Referring to Figures 5 and 6, the display substrate includes a substrate 200 and a plurality of sub-pixels located on the substrate 200. The plurality of sub-pixels includes a plurality of first sub-pixel columns PR1 and a plurality of second sub-pixel columns PR2, which are alternately arranged along a first direction X. Each first sub-pixel column PR1 includes a plurality of first sub-pixels SP1 and a plurality of second sub-pixels SP2, which are alternately and spaced apart along a second direction Y, where the first direction X and the second direction Y intersect. Each second sub-pixel column PR2 includes a plurality of third sub-pixels SP3, which are spaced apart along the second direction Y. Adjacent first sub-pixels SP1 and SP2 along the second direction, and a third sub-pixel SP3 adjacent to both first sub-pixels SP1 and SP2, constitute a pixel unit PX.

[0080] The display substrate includes a driving circuit layer 300 on a substrate 200 and a light-emitting device layer 400 on the side of the driving circuit layer 300 away from the substrate 200. A sub-pixel includes a pixel driving unit located on the driving circuit layer 300 and a light-emitting device 400a located on the light-emitting device layer 400, with the light-emitting device 400a and the pixel driving unit electrically connected.

[0081] The light-emitting device layer 400 includes a first electrode layer 410 located on the side of the driving circuit layer 300 away from the substrate 200, a light-emitting layer 420 located on the side of the first electrode layer 410 away from the substrate 200, and a second electrode layer 430 located on the side of the light-emitting layer 420 away from the substrate 200. A pixel defining layer PDL is further disposed between the light-emitting layer 420 and the first electrode layer 410. The pixel defining layer PDL has a first pixel opening PK1, a second pixel opening PK2, and a third pixel opening PK3. The light-emitting layer 420 includes a first light-emitting sublayer 421, a second light-emitting sublayer 422, and a third light-emitting sublayer 423. The first light-emitting sublayer 421 is located within the first pixel opening PK1 and serves as the light-emitting layer for a first sub-pixel SP1. The second light-emitting sublayer 422 is located within the second pixel opening PK2 and serves as the light-emitting layer for a second sub-pixel SP2. The third light-emitting sublayer 423 is located within the third pixel opening PK3 and serves as the light-emitting layer for a third sub-pixel SP3. The first sub-pixel SP1 has a first pixel aperture PK1, the second sub-pixel SP2 has a second pixel aperture PK2, and the third sub-pixel SP3 has a third pixel aperture PK3. The area of ​​the orthographic projection of the third pixel aperture PK3 onto the substrate 200 is smaller than the area of ​​the orthographic projection of the first pixel aperture PK1 onto the substrate 200, and the area of ​​the orthographic projection of the third pixel aperture PK3 onto the substrate 200 is smaller than the area of ​​the orthographic projection of the second pixel aperture PK2 onto the substrate 200. By arranging the third sub-pixels SP3 with the smallest pixel aperture area in the same column along the second direction Y, the width of the third pixel aperture PK3 of the third sub-pixels SP3 along the first direction X can be effectively narrowed. Thus, when the spacing between two adjacent third sub-pixels SP3 along the second direction Y is constant, that is, when the spacing between two adjacent third pixel aperture PK3 along the second direction Y is constant, the area of ​​the interval region between two adjacent third pixel aperture PK3 along the second direction Y can be reduced, thereby improving the aperture ratio of the display substrate.

[0082] It should be noted that the area where the first pixel opening PK1 is located is roughly the light-emitting area of ​​the first sub-pixel SP1, the area where the second pixel opening PK2 is located is roughly the light-emitting area of ​​the second sub-pixel SP2, and the area where the third pixel opening PK3 is located is roughly the light-emitting area of ​​the third sub-pixel SP3.

[0083] Furthermore, referring to Figure 6, due to the fabrication process of the pixel defining layer (PDL), the opening area of ​​the first pixel opening PK1 on the side near the substrate 200 is smaller than the opening area of ​​the first pixel opening PK1 on the side away from the substrate 200; the opening area of ​​the second pixel opening PK2 on the side near the substrate 200 is smaller than the opening area of ​​the second pixel opening PK2 on the side away from the substrate 200; and the opening area of ​​the third pixel opening PK3 on the side near the substrate 200 is smaller than the opening area of ​​the third pixel opening PK3 on the side away from the substrate 200. In this text, the first pixel opening PK1 should be understood as the opening of the side of the pixel defining layer (PDL) near the substrate 200 at the first pixel opening PK1; the second pixel opening PK2 should be understood as the opening of the side of the pixel defining layer (PDL) near the substrate 200 at the second pixel opening PK2; and the third pixel opening PK3 should be understood as the opening of the side of the pixel defining layer (PDL) near the substrate 200 at the third pixel opening PK3. The aperture ratio of the display substrate should be understood as the percentage of the sum of the areas of the first pixel opening PK1, the second pixel opening PK2, and the third pixel opening PK3 to the area of ​​the pixel unit PX.

[0084] According to some exemplary embodiments, referring to FIG5, the first sub-pixel SP1 is a green sub-pixel, the second sub-pixel SP2 is a blue sub-pixel, and the third sub-pixel SP3 is a red sub-pixel. That is, the first sub-pixel SP1 emits green light, the second sub-pixel SP2 emits blue light, and the third sub-pixel SP3 emits red light.

[0085] It should be noted that in the pixel arrangement shown in Figure 5, in pixel unit PX, the first sub-pixel SP1 is located above the second sub-pixel SP2. Depending on the actual needs, it can also be adjusted so that the first sub-pixel SP1 is located below the second sub-pixel SP2.

[0086] According to some exemplary embodiments, referring to FIG5, the size of the pixel openings of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 is set based on factors such as the luminous efficiency and luminous brightness of the light-emitting devices in the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3, so as to enable the display substrate to have a better display effect. When the first sub-pixel SP1 is a green sub-pixel, the second sub-pixel SP2 is a blue sub-pixel, and the third sub-pixel SP3 is a red sub-pixel, the ratio of the area of ​​the first pixel opening PK1 to the area of ​​the third pixel opening PK3 is greater than 1 and less than or equal to 4, and the ratio of the area of ​​the second pixel opening PK2 to the area of ​​the third pixel opening PK3 is greater than or equal to 1.5 and less than or equal to 5.

[0087] For example, the ratio of the area of ​​the first pixel opening PK1 to the area of ​​the third pixel opening PK3 is 1.1, 1.2, 1.3, 1.4, 1.5, 2, 2.5, 3, 3.5 or 4, etc.

[0088] For example, the ratio of the area of ​​the second pixel opening PK2 to the area of ​​the third pixel opening PK3 is 1.5, 2, 2.5, 3, 3.5, 4, 4.5 or 5, etc.

[0089] According to some exemplary embodiments, the distance between two adjacent third pixel openings PK3 along the second direction Y is a first distance D1, and the distance between the first pixel opening PK1 and the adjacent second pixel opening PK2 along the second direction Y is a second distance D2, and the second distance D2 is less than half of the first distance D1.

[0090] The inventors discovered that when the pixel arrangement shown in Figure 2A is changed to the pixel arrangement shown in Figure 5, since the size of the pixel unit PX is fixed, that is, the size of the pixel unit PX along the first direction X and the size along the second direction Y are fixed, the spacing between the first sub-pixel column PR1 and the second sub-pixel column PR2 along the first direction X will not change. Therefore, the area of ​​the gap region between the first sub-pixel column PR1 and the second sub-pixel column PR2 will not change.

[0091] In addition, factors that can change and thus affect the opening include the area of ​​the gap between adjacent first sub-pixels SP1 and second sub-pixels SP2 in the first sub-pixel column PR1, and the area of ​​the gap between adjacent third sub-pixels SP3 in the second sub-pixel column PR2.

[0092] Since the size of the pixel unit PX along the second direction Y is constant, when the pixel arrangement shown in Figure 2A is changed to the pixel arrangement shown in Figure 5, the width of the first sub-pixel SP1 and the second sub-pixel SP2 in the first sub-pixel column PR1 along the first direction X increases by x, and the width of the third sub-pixel SP3 in the second sub-pixel column PR2 along the first direction X decreases by x. Then, the total area of ​​the increased spacing region between the first sub-pixel SP1 and the second sub-pixel SP2 in a column of the first sub-pixel column PR1 is 2*n*x*D2, and the total area of ​​the decreased spacing region between adjacent third sub-pixels SP3 in a column of the second sub-pixel column PR2 is n*x*D1. When the total area of ​​the increased spacing region is less than the total area of ​​the decreased spacing region, that is, 2*n*x*D2 < n*x*D1, or D2 < 0.5*D1, the aperture ratio of the display substrate can be increased.

[0093] It should be noted that n represents the number of first sub-pixels SP1 or second sub-pixels SP2 in the first sub-pixel column PR1, and n also represents the number of third sub-pixels SP3 in the second sub-pixel column PR2, where n is a positive integer.

[0094] According to some exemplary embodiments, referring to FIG5, the size W3 of the third pixel opening PK3 along the first direction X is smaller than the size H3 of the third pixel opening PK3 along the second direction Y. Since the third sub-pixels SP3 are arranged in a row along the second direction Y, the size of the third pixel opening PK3 along the first direction X is set to be smaller, which can reduce the size of the gap area (i.e., the rib area RA shown in FIG5) between adjacent third sub-pixels SP3 along the second direction Y due to the ribs present in the FMM used for vapor deposition.

[0095] According to some exemplary embodiments, referring to FIG5, the dimension W3 of the third pixel opening PK3 along the first direction X is less than or equal to half of the dimension H3 of the third pixel opening PK3 along the second direction Y. Because the area of ​​the third pixel opening PK3 is small, when multiple third sub-pixels SP3 are arranged in the same column, the dimension W3 of the third pixel opening PK3 along the first direction X is small, making W3 ≤ 0.5 * H3. This is beneficial for further reducing the area of ​​the gap region between adjacent third sub-pixels SP3 along the second direction Y caused by the ribs present in the FMM used for vapor deposition.

[0096] According to some exemplary embodiments, referring to FIG5, the dimension W3 of the third pixel opening PK3 along the first direction X is smaller than the dimension W1 of the first pixel opening PK1 along the first direction X, and the dimension W3 of the third pixel opening PK3 along the first direction X is smaller than the dimension W2 of the second pixel opening PK2 along the first direction X. That is, the width of the second sub-pixel column PR2 along the first direction X is narrower than the width of the first sub-pixel column PR1 along the first direction X, which is beneficial to reduce the area of ​​the gap region between adjacent third sub-pixels SP3 in the second sub-pixel column PR2 caused by the ribs present in the FMM used for vapor deposition.

[0097] According to some exemplary embodiments, referring to FIG5, the size W3 of the third pixel opening PK3 along the first direction X is less than half the size W1 of the first pixel opening PK1 along the first direction X, and the size W3 of the third pixel opening PK3 along the first direction X is less than half the size W2 of the second pixel opening PK2 along the first direction X. Because the area of ​​the third pixel opening PK3 is small, when multiple third sub-pixels SP3 are arranged in the same column, the size W3 of the third pixel opening PK3 along the first direction X is small, making W3 ≤ 0.5 * W2 and W3 ≤ 0.5 * W1. This is beneficial for further reducing the size of the gap region between adjacent third sub-pixels SP3 along the second direction Y due to the ribs present in the FMM used for vapor deposition.

[0098] According to some exemplary embodiments, referring to FIG5, the size H3 of the third pixel opening PK3 along the second direction Y is greater than the size H1 of the first pixel opening PK1 along the second direction Y, and the size H3 of the third pixel opening PK3 along the second direction Y is greater than the size H2 of the second pixel opening PK2 along the second direction Y.

[0099] According to some exemplary embodiments, referring to FIG5, the size W1 of the first pixel opening PK1 along the first direction X is greater than or equal to the size H1 of the first pixel opening PK1 along the second direction Y, and the size W2 of the second pixel opening PK2 along the first direction X is greater than or equal to the size H2 of the second pixel opening PK2 along the second direction Y.

[0100] According to some exemplary embodiments, referring to FIG5, the shapes of the first pixel opening PK1, the second pixel opening PK2, and the third pixel opening PK3 are all rectangular. Due to factors such as the fabrication process of the pixel boundary layer (PDL), the shapes of the first pixel opening PK1, the second pixel opening PK2, and the third pixel opening PK3 can be rounded rectangles, for example, the radius of curvature at the corners can be 1-2 micrometers.

[0101] Optionally, the shapes of the first pixel opening PK1, the second pixel opening PK2, and the third pixel opening PK3 can also be other shapes, such as triangles, rhombuses, or hexagons.

[0102] According to some exemplary embodiments, referring to FIG5, the size W2 of the second pixel opening PK2 along the first direction X is approximately equal to the size W1 of the first pixel opening PK1 along the first direction X. Setting the first sub-pixel SP1 and the second sub-pixel SP2 located in the first sub-pixel column PR1 to have the same width is beneficial to reducing the area of ​​the interval region between the first sub-pixel SP1 and the second sub-pixel SP2 in the first sub-pixel column PR1, thereby improving the aperture ratio of the display substrate.

[0103] Figure 7 schematically illustrates a pixel arrangement diagram of a display substrate according to some embodiments of the present disclosure.

[0104] According to some exemplary embodiments, referring to FIG7, a pixel unit PX is formed by a first sub-pixel SP1 and a second sub-pixel SP2 adjacent along the second direction Y, and a third sub-pixel SP3 adjacent along the first direction X of the first sub-pixel SP1 and the second sub-pixel SP2. In the pixel unit PX, the geometric center of the orthographic projection of the first pixel opening PK1 onto the substrate is the first center PC1, the geometric center of the orthographic projection of the second pixel opening PK2 onto the substrate is the second center PC2, and the geometric center of the orthographic projection of the third pixel opening PK3 onto the substrate is the third center PC3. In the second direction Y, the third center PC3 is located on the side closer to the second center PC2 than the midpoint MP of the line connecting the first center PC1 and the second center PC2.

[0105] The inventors discovered that when the resolution of the display substrate is low, for example, when the PPI (Pixels Per Inch) of the display substrate is less than 326, the pixel center of the first sub-pixel SP1 (green sub-pixel) with the highest brightness in a pixel unit PX can be dispersed in the second direction Y, which is beneficial to visually reduce the display graininess of the display substrate.

[0106] According to some exemplary embodiments, referring to FIG7, in pixel unit PX, the side of the third pixel opening PK3 away from the first sub-pixel SP1 along the second direction Y is substantially flush with the side of the second pixel opening PK2 away from the first sub-pixel SP1 along the second direction Y along the first direction X, so that the third center PC3 can be set in a direction close to the second center PC2, so that the pixel center of the first sub-pixel SP1 and the pixel center of the third sub-pixel SP3 are dispersed in the second direction Y, which is beneficial to further reduce the display graininess of the display substrate visually.

[0107] It should be noted that, due to factors such as the patterning process precision of the pixel delimiting layer, the side of the third pixel opening PK3 away from the first sub-pixel SP1 along the second direction Y is difficult to be completely flush with the side of the second pixel opening PK2 away from the first sub-pixel SP1 along the second direction Y. The side of the third pixel opening PK3 away from the first sub-pixel SP1 along the second direction Y and the side of the second pixel opening PK2 away from the first sub-pixel SP1 along the second direction Y are basically flush with the side along the first direction X. It should be understood that the distance between the side of the third pixel opening PK3 away from the first sub-pixel SP1 along the second direction Y and the side of the second pixel opening PK2 away from the first sub-pixel SP1 along the second direction Y should be less than or equal to a preset distance. This preset distance depends on the patterning process precision of the pixel delimiting layer. For example, this preset distance can be 1μm.

[0108] Figure 8 schematically illustrates a pixel arrangement diagram of a display substrate according to some embodiments of the present disclosure.

[0109] According to some exemplary embodiments, referring to FIG8, within a pixel unit PX, a first sub-pixel SP1 and a second sub-pixel SP2 adjacent along the second direction Y, and a third sub-pixel SP3 adjacent to the first sub-pixel SP1 and the second sub-pixel SP2 along the first direction X, constitute a pixel unit PX. In this pixel unit PX, the geometric center of the orthographic projection of the first pixel opening PK1 onto the substrate is the first center PC1, the geometric center of the orthographic projection of the second pixel opening PK2 onto the substrate is the second center PC2, and the geometric center of the orthographic projection of the third pixel opening PK3 onto the substrate is the third center PC3. In the second direction Y, the third center PC3 is located on the side closer to the first center PC1 than the midpoint MP of the line connecting the first center PC1 and the second center PC2.

[0110] The inventors discovered that when the resolution of the display substrate is high, for example, when the PPI (Pixels Per Inch) of the display substrate is greater than or equal to 326, the pixel center of the first sub-pixel SP1 (green sub-pixel G) with the highest brightness in a pixel unit PX and the pixel center of the third sub-pixel SP3 (red sub-pixel R) with the second highest brightness can be set more closely in the second direction Y, which is beneficial to increasing the display sharpness of the display substrate.

[0111] According to some exemplary embodiments, referring to FIG8, the side of the third pixel opening PK3 away from the second sub-pixel SP2 along the second direction Y is substantially flush with the side of the first pixel opening PK1 away from the second sub-pixel SP2 along the second direction Y along the first direction X, so that the third center PC3 can be set towards the direction of the first center PC1, so that the pixel center of the first sub-pixel SP1 and the pixel center of the third sub-pixel SP3 are closer in the second direction Y, which is beneficial to further increase the display sharpness of the display substrate.

[0112] It should be noted that, due to factors such as the patterning process precision of the pixel delimiting layer, the side of the third pixel opening PK3 away from the second sub-pixel SP2 along the second direction Y is difficult to be completely flush with the side of the first pixel opening PK1 away from the second sub-pixel SP2 along the second direction Y. The side of the third pixel opening PK3 away from the second sub-pixel SP2 along the second direction Y and the side of the first pixel opening PK1 away from the second sub-pixel SP2 along the second direction Y are basically flush with the side along the first direction X. It should be understood that the distance between the side of the third pixel opening PK3 away from the second sub-pixel SP2 along the second direction Y and the side of the first pixel opening PK1 away from the second sub-pixel SP2 along the first direction X should be less than or equal to a preset distance. This preset distance depends on the patterning process precision of the pixel delimiting layer. For example, this preset distance can be 1μm.

[0113] Figure 9 schematically shows a plan view of a third pixel aperture and driving circuit layer combination of some display substrates according to embodiments of the present disclosure.

[0114] According to some exemplary embodiments, referring to Figures 6 and 9, the display substrate includes a driving circuit layer 300 on a substrate 200 and a light-emitting device layer 400 on the side of the driving circuit layer 300 away from the substrate 200. The driving circuit layer 300 includes a source / drain metal layer SD closest to the light-emitting device layer 400. The source / drain metal layer SD includes a power signal line VDD extending along the second direction Y. The orthographic projection of the third pixel opening PK3 on the substrate 200 is located within the orthographic projection of the power signal line VDD on the substrate 200. The size of the power signal line VDD along the first direction X is larger than the size of the third pixel opening PK3 along the first direction X. The third sub-pixel SP3 can be set on the side of the power signal line VDD away from the substrate 200. The third sub-pixel SP3 is raised by the wider power signal line VDD to ensure the flatness of the third sub-pixel SP3, thereby effectively avoiding the color shift problem of the third sub-pixel SP3.

[0115] It should be noted that the power signal line VDD can be configured to connect a first power signal to the first electrode of the light-emitting device. This first power signal is a high-level signal. By setting the linewidth of the power signal line VDD to be wider, the voltage drop generated by the transmission of the first power signal within the power signal line VDD can be effectively reduced. Based on this, considering that the third sub-pixel SP3 has a smaller size along the first direction X and is an elongated strip extending along the second direction Y, it is more prone to color shift problems compared to the first and second sub-pixels. Therefore, the flatness of the third sub-pixel SP3 can be ensured by using the power signal line VDD to pad the third sub-pixel SP3.

[0116] Figure 10 schematically shows a plan view of a third pixel aperture and driving circuit layer combination of some display substrates according to embodiments of the present disclosure.

[0117] According to some exemplary embodiments, referring to Figures 6 and 10, the display substrate includes a driving circuit layer 300 on a substrate 200 and a light-emitting device layer 400 on the side of the driving circuit layer 300 away from the substrate 200. The driving circuit layer 300 includes a source / drain metal layer SD closest to the light-emitting device layer 400. The source / drain metal layer SD includes a data signal line Data extending along the second direction Y. The orthographic projection of the third pixel opening PK3 on the substrate 200 partially overlaps with the orthographic projection of the data signal line Data on the substrate 200, and the geometric center PC3 of the orthographic projection of the third pixel opening PK3 on the substrate 200 is located within the orthographic projection of the data signal line Data on the substrate 200. The size of the data signal line Data along the first direction X is smaller than the size of the third pixel opening PK3 along the first direction X. Therefore, the data signal line Data cannot completely pad the third sub-pixel SP3. By placing the geometric center PC3 of the orthographic projection of the third pixel opening PK3 on the substrate 200 within the orthographic projection of the data signal line Data on the substrate 200, the symmetry of the third sub-pixel SP3 along the first direction X can be basically guaranteed, thereby effectively avoiding the color shift problem of the third sub-pixel SP3.

[0118] Figure 11 schematically shows a plan view of a third pixel aperture and driving circuit layer combination of some display substrates according to embodiments of the present disclosure.

[0119] According to some exemplary embodiments, referring to Figures 6 and 11, the display substrate includes a driving circuit layer 300 on a substrate 200 and a light-emitting device layer 400 on the side of the driving circuit layer 300 away from the substrate 200. The driving circuit layer 300 includes a source / drain metal layer SD closest to the light-emitting device layer 400. The source / drain metal layer SD includes a data signal line Data extending along a second direction Y and a blank trace DL extending along the second direction Y. The first portion PK31 of the orthographic projection of the third pixel opening PK3 on the substrate 200 overlaps with the orthographic projection of the data signal line Data on the substrate 200, and the second portion PK32 of the orthographic projection of the third pixel opening PK3 on the substrate 200 overlaps with the orthographic projection of the blank trace DL on the substrate 200. The first portion PK31 and the second portion PK32 are respectively located on both sides of the geometric center PC3 of the orthographic projection of the third pixel opening PK3 on the substrate 200 along the first direction X. With this setting, the third sub-pixel SP3 is padded with data signal lines Data and blank traces DL on both sides along the first direction X, which can ensure the symmetry of the third sub-pixel SP3 along the first direction X, and thus effectively avoid the color shift problem of the third sub-pixel SP3.

[0120] It should be noted that blank traces (DL) do not connect to signals, therefore, blank traces (DL) should not be set too long. The length of blank traces (DL) along the second direction (Y) should be slightly greater than the length of the third pixel opening (PK3) along the second direction (Y). In other words, multiple blank traces (DL) should be arranged at intervals along the second direction (Y).

[0121] According to some exemplary embodiments, the size of the blank trace DL along the first direction X is substantially equal to the size of the data signal line Data along the first direction X, so as to ensure the symmetry of the third sub-pixel SP3 along the first direction X.

[0122] According to some exemplary embodiments, the distance between the geometric center PC3 of the orthographic projection of the third pixel opening PK3 on the substrate 200 and the orthographic projection of the overlapping data signal line Data on the substrate 200 is substantially equal to the distance between the geometric center PC3 of the orthographic projection of the third pixel opening PK3 on the substrate 200 and the orthographic projection of the overlapping blank trace DL on the substrate 200.

[0123] It should be noted that the statement that the two dimensions involved in the embodiments of this disclosure are substantially equal should be understood as one dimension deviating from the other dimension by within ±10%.

[0124] Figure 12 schematically shows a plan view of a third pixel aperture and driving circuit layer combination of some display substrates according to embodiments of the present disclosure.

[0125] According to some exemplary embodiments, the display substrate includes a driving circuit layer 300 on a substrate 200 and a light-emitting device layer 400 on the side of the driving circuit layer 300 away from the substrate 200. The driving circuit layer 300 includes a source / drain metal layer SD closest to the light-emitting device layer 400. The source / drain metal layer SD includes multiple signal traces SL. The multiple signal traces SL extend along a second direction Y and are arranged along a first direction X. The orthographic projection of the third pixel opening PK3 on the substrate 200 is located between the orthographic projections of two adjacent signal traces SL on the substrate 200. Since the size of the third pixel opening PK3 along the first direction X is small, the third pixel opening PK3 can be placed between two adjacent signal traces SL. That is, the third sub-pixel SP3 is not raised by the signal traces SL in the source / drain metal layer SD, thereby ensuring the flatness of the third sub-pixel SP3 and effectively avoiding the color shift problem of the third sub-pixel SP3.

[0126] According to some exemplary embodiments, the source / drain metal layer SD includes multiple signal traces SL, which include multiple power signal lines VDD and multiple data signal lines Data. Two data signal lines Data can be disposed between two adjacent power signal lines VDD. The orthographic projection of the third pixel opening PK3 on the substrate 200 can be located between the orthographic projections of adjacent power signal lines VDD and data signal lines Data on the substrate 200 (Figure 12 schematically illustrates this situation), or the orthographic projection of the third pixel opening on the substrate can be located between the orthographic projections of two adjacent data signal lines on the substrate.

[0127] Figures 13A-13C schematically illustrate plan views of some mask plates according to embodiments of the present disclosure.

[0128] At least some embodiments of this disclosure also provide a mask for fabricating a display substrate as described in the above embodiments. The mask includes a first sub-mask FMM1, a second sub-mask FMM2, and a third sub-mask FMM3. Referring to FIG5 and FIG13A, the first sub-mask FMM1 is used to fabricate a first sub-pixel SP1. The first sub-mask FMM1 includes a plurality of first openings KK1 arranged in an array, which are used for vapor deposition to form a light-emitting layer for a plurality of first sub-pixels SP1. Referring to FIG5 and FIG13B, the second sub-mask FMM2 is used to fabricate a second sub-pixel SP2. The second sub-mask FMM2 includes a plurality of second openings KK2 arranged in an array, which are used for vapor deposition to form a light-emitting layer for a plurality of second sub-pixels SP2. Referring to Figures 5 and 13C, the third sub-mask FMM3 is used to fabricate the third sub-pixel SP3. The third sub-mask FMM3 includes a plurality of third openings KK3 arranged in an array. The plurality of third openings KK3 are used for vapor deposition to form the light-emitting layer of the plurality of third sub-pixels SP3. Since the area of ​​the third pixel opening PK3 is smaller than the area of ​​the first pixel opening PK1 and the second pixel opening PK2, the area of ​​the third opening KK3 is smaller than the area of ​​the first opening KK1 and the area of ​​the third opening KK3 is smaller than the area of ​​the second opening KK2.

[0129] According to some exemplary embodiments, referring to Figures 5 and 13C, the distance RH2 between two adjacent third openings KK3 along the second direction Y is greater than the second distance D2 between adjacent first pixel openings PK1 and second pixel openings PK2 along the second direction Y. This allows the first distance D1 between two adjacent third pixel openings PK3 along the second direction Y in the formed display substrate to be greater than twice the second distance D2 between the first pixel opening PK1 and adjacent second pixel openings PK2 along the second direction Y (refer to Figure 5), thereby increasing the aperture ratio of the display substrate. A detailed description follows with reference to a specific display substrate.

[0130] Display substrates 1 and 4 were prepared, and the aperture ratio data of display substrates 1 and 4 were measured and calculated. The results are shown in Table 1.

[0131] Table 1

[0132] The pixel arrangement of display substrate 1 and display substrate 3 is shown in Figure 2A. That is, multiple blue sub-pixels are arranged in a row along the second direction, and multiple red sub-pixels and multiple green sub-pixels are arranged alternately in a row along the second direction. In display substrate 1 and display substrate 3, Rib represents the spacing of adjacent openings along the second direction in the FMM (as shown in Figure 3A) used for vapor deposition to form blue sub-pixels.

[0133] The pixel arrangement of display substrates 2 and 4 is shown in Figure 5. That is, multiple red sub-pixels are arranged in a row along the second direction, and multiple blue sub-pixels and multiple green sub-pixels are arranged alternately in a row along the second direction. In display substrates 2 and 4, Rib represents the spacing of adjacent third openings along the second direction in the FMM (as shown in Figure 13C) used for vapor deposition to form red sub-pixels.

[0134] Pixel Pitch represents the size of a pixel unit. It can be understood as the distance between a specific point in one pixel unit and the same point in another pixel unit in two adjacent pixel units along a first direction, or it can be understood as the distance between a specific point in one pixel unit and the same point in another pixel unit in two adjacent pixel units along a second direction.

[0135] PDL Gap should be understood as the width of the pixel boundary layer between adjacent sub-pixels of different colors, that is, the spacing between the pixel openings of adjacent sub-pixels of different colors.

[0136] In display substrates 1 and 3, the PDL Gap can be the distance between the pixel opening of a red sub-pixel and the pixel opening of an adjacent green sub-pixel along a second direction, or it can be the distance between the pixel opening of a red sub-pixel and the pixel opening of an adjacent blue sub-pixel along a first direction, or it can be the distance between the pixel opening of a green sub-pixel and the pixel opening of an adjacent blue sub-pixel along a first direction. Furthermore, the distance between the openings of two adjacent blue sub-pixels along the second direction is approximately equal to the sum of the PDL Gap and Rib(BB).

[0137] In display substrates 2 and 4, the PDL Gap can be the distance between the pixel opening of a blue sub-pixel and the pixel opening of an adjacent green sub-pixel along a second direction, or it can be the distance between the pixel opening of a red sub-pixel and the pixel opening of an adjacent blue sub-pixel along a first direction, or it can be the distance between the pixel opening of a red sub-pixel and the pixel opening of an adjacent green sub-pixel along a first direction. Furthermore, the distance between the openings of two adjacent red sub-pixels along the second direction is approximately equal to the sum of the PDL Gap and Rib(RR).

[0138] R:G:B represents the area ratio of the pixel aperture of the red sub-pixel, the pixel aperture of the green sub-pixel, and the pixel aperture of the blue sub-pixel. R AR (%) represents the percentage of the pixel aperture area of ​​the red sub-pixel to the total area of ​​the pixel unit, G AR (%) represents the percentage of the pixel aperture area of ​​the green sub-pixel to the total area of ​​the pixel unit, B AR (%) represents the percentage of the pixel aperture area of ​​the blue sub-pixel to the total area of ​​the pixel unit, and Total AR (%) represents the percentage of the sum of the pixel aperture areas of the red, green, and blue sub-pixels to the total area of ​​the pixel unit, which is the total aperture ratio of the display substrate.

[0139] Comparing the data of display substrate 1 and display substrate 2, or display substrate 3 and display substrate 4, it can be seen that, with Rib, Pixel Pitch, R:G:B, and PDL Gap fixed, when the pixel arrangement of the display substrate is changed from Figure 2A to Figure 5, the aperture ratios of red subpixels, green subpixels, blue subpixels, and the total aperture ratio are all improved. The total aperture ratio of display substrate 2 is 1.42% higher than that of display substrate 1, and the total aperture ratio of display substrate 4 is 0.94% higher than that of display substrate 3. This verifies that when Rib is greater than PDL Gap, the aperture ratio of the display substrate is improved, and the larger the difference between Rib and PDL Gap, the greater the improvement in aperture ratio.

[0140] Display substrates 5 and 8 were fabricated, and the aperture ratio data of display substrates 5 and 8 were measured and calculated. The results are shown in Table 2.

[0141] Table 2

[0142] The pixel arrangement of display substrates 5 and 7 is shown in Figure 2A, meaning that multiple blue sub-pixels are arranged in a column along the second direction, and multiple red and multiple green sub-pixels are alternately arranged in a column along the second direction. The pixel arrangement of display substrates 6 and 8 is shown in Figure 5, meaning that multiple red sub-pixels are arranged in a column along the second direction, and multiple blue and multiple green sub-pixels are alternately arranged in a column along the second direction. Furthermore, the meanings of the relevant parameters in Table 2 can be found in the previous explanation of the relevant parameters in Table 1, and will not be repeated here.

[0143] Comparing the data of display substrate 5 and display substrate 6, or display substrate 7 and display substrate 8, it can be seen that, with Rib, Pixel Pitch, R:G:B, and PDL Gap fixed, when the pixel arrangement of the display substrate is changed from Figure 2A to Figure 5, the aperture ratios of red subpixels, green subpixels, blue subpixels, and the total aperture ratio are all improved. The total aperture ratio of display substrate 6 is 1.84% higher than that of display substrate 5, and the total aperture ratio of display substrate 8 is 1.24% higher than that of display substrate 7. This verifies that when Rib is greater than PDL Gap, the aperture ratio of the display substrate is improved, and the larger the difference between Rib and PDL Gap, the greater the improvement in aperture ratio.

[0144] Display substrates 9 and 12 were fabricated, and the aperture ratio data of display substrates 9 and 12 were measured and calculated. The results are shown in Table 3.

[0145] Table 3

[0146] The pixel arrangement of display substrates 9 and 11 is shown in Figure 2A, meaning that multiple blue sub-pixels are arranged in a column along the second direction, and multiple red and multiple green sub-pixels are alternately arranged in a column along the second direction. The pixel arrangement of display substrates 6 and 8 is shown in Figure 5, meaning that multiple red sub-pixels are arranged in a column along the second direction, and multiple blue and multiple green sub-pixels are alternately arranged in a column along the second direction. Furthermore, the meanings of the relevant parameters in Table 3 can be found in the previous explanation of the relevant parameters in Table 1, and will not be repeated here.

[0147] Comparing the data of display substrate 9 and display substrate 10, or display substrate 11 and display substrate 12, it can be seen that when the pixel arrangement of the display substrate is changed from Figure 2A to Figure 5, the aperture ratios of red sub-pixels, green sub-pixels, blue sub-pixels, and the total aperture ratio are all improved, provided that Rib, Pixel Pitch, R:G:B, and PDL Gap are constant. The total aperture ratio of display substrate 10 is 6.22% higher than that of display substrate 9, and the total aperture ratio of display substrate 12 is 5.34% higher than that of display substrate 11. This verifies that when Rib is greater than PDL Gap, the aperture ratio of the display substrate is improved, and the larger the difference between Rib and PDL Gap, the greater the improvement in aperture ratio.

[0148] Furthermore, comparing the data of display substrate 6 and display substrate 10, or comparing the data of display substrate 8 and display substrate 12, it can be seen that, under the condition that the pixel pitch, R:G:B, PDL gap and pixel arrangement are fixed, reducing the Rib can increase the total aperture ratio of the display substrate. However, when the Rib is small, due to the manufacturing process of FMM, the shadow height at the Rib is larger, which makes the PDL gap at the Rib larger, thus leading to a decrease in the total aperture ratio of the display substrate. Therefore, the value of Rib needs to be specifically designed to balance the aperture ratio loss caused by the values ​​of Rib and PDL, thereby ensuring that the display substrate has a high aperture ratio.

[0149] For example, with an FMM thickness of 25 μm, the Rib can be set to 40 μm and the Shadow Height at the Rib to 4 μm. Alternatively, the Rib can be set to 25 μm and the Shadow Height at the Rib to 6 μm. Or, the Rib can be set to 19 μm and the Shadow Height at the Rib to 8 μm.

[0150] At least some embodiments of this disclosure also provide a display device comprising the display substrate described above. The display device may include any device or product with display functionality. For example, the display device may be a smartphone, mobile phone, e-book reader, desktop computer (PC), laptop PC, netbook PC, personal digital assistant (PDA), portable multimedia player (PMP), digital audio player, mobile medical device, camera, wearable device (e.g., head-mounted device, electronic clothing, electronic bracelet, electronic necklace, electronic accessory, electronic tattoo, or smartwatch), television set, etc.

[0151] As used herein, the terms “substantially,” “approximately,” “about,” and other similar terms are used as terms of approximation rather than as terms of degree, and they are intended to account for inherent deviations in measured or calculated values ​​that would be recognized by one of ordinary skill in the art. Taking into account factors such as process variations, measurement problems, and errors associated with the measurement of a particular quantity (i.e., limitations of the measurement system), “approximately” or “about” as used herein includes the stated value and indicates that the particular value is within an acceptable range of deviation for one of ordinary skill in the art. For example, “approximately” may mean within one or more standard deviations, or within ±10% or ±5% of the stated value.

[0152] While some embodiments based on the general inventive concept of this disclosure have been illustrated and described, those skilled in the art will understand that changes may be made to these embodiments without departing from the principles and spirit of the general inventive concept of this disclosure, the scope of which is defined by the claims and their equivalents.

Claims

1. A display substrate, wherein, The display substrate includes: Substrate; and Multiple sub-pixels are located on the substrate. The multiple sub-pixels include multiple first sub-pixel columns and multiple second sub-pixel columns, which are alternately arranged along a first direction. Each first sub-pixel column includes multiple first sub-pixels and multiple second sub-pixels. These multiple first and second sub-pixels are alternately and spaced apart along a second direction, where the first and second directions intersect. Each second sub-pixel column includes multiple third sub-pixels, which are spaced apart along the second direction. Wherein, the first sub-pixel has a first pixel opening, the second sub-pixel has a second pixel opening, and the third sub-pixel has a third pixel opening. The area of ​​the orthographic projection of the third pixel opening on the substrate is smaller than the area of ​​the orthographic projection of the first pixel opening on the substrate, and the area of ​​the orthographic projection of the third pixel opening on the substrate is smaller than the area of ​​the orthographic projection of the second pixel opening on the substrate.

2. The display substrate according to claim 1, wherein, The size of the third pixel opening along the first direction is smaller than the size of the third pixel opening along the second direction.

3. The display substrate according to claim 2, wherein, The size of the third pixel opening along the first direction is less than or equal to half the size of the third pixel opening along the second direction.

4. The display substrate according to any one of claims 1-3, wherein, The size of the third pixel opening along the first direction is smaller than the size of the first pixel opening along the first direction; and / or The size of the third pixel opening along the first direction is smaller than the size of the second pixel opening along the first direction.

5. The display substrate according to claim 4, wherein, The size of the third pixel opening along the first direction is less than half the size of the first pixel opening along the first direction; and / or, The size of the third pixel opening along the first direction is less than half the size of the second pixel opening along the first direction.

6. The display substrate according to any one of claims 1-5, wherein, The size of the third pixel opening along the second direction is larger than the size of the first pixel opening along the second direction; and / or, The size of the third pixel opening along the second direction is larger than the size of the second pixel opening along the second direction.

7. The display substrate according to any one of claims 1-6, wherein, The size of the first pixel opening along the first direction is greater than or equal to the size of the first pixel opening along the second direction; and / or, The size of the second pixel opening along the first direction is greater than or equal to the size of the second pixel opening along the second direction.

8. The display substrate according to any one of claims 1-7, wherein, The distance between two adjacent third pixel openings along the second direction is the first distance, and the distance between the first pixel opening and the adjacent second pixel opening along the second direction is the second distance, wherein the second distance is less than half of the first distance.

9. The display substrate according to any one of claims 1-8, wherein, The third sub-pixel is a red sub-pixel, the first sub-pixel is a green sub-pixel, and the second sub-pixel is a blue sub-pixel.

10. The display substrate according to any one of claims 1-9, wherein, The ratio of the opening area of ​​the first pixel to the opening area of ​​the third pixel is greater than 1 and less than or equal to 4; and / or, The ratio of the opening area of ​​the second pixel to the opening area of ​​the third pixel is greater than or equal to 1.5 and less than or equal to 5.

11. The display substrate according to any one of claims 1-10, wherein, In the first sub-pixel and the second sub-pixel adjacent along the second direction, and the third sub-pixel adjacent along the first direction, the geometric center of the orthographic projection of the opening of the first pixel on the substrate is the first center, the geometric center of the orthographic projection of the opening of the second pixel on the substrate is the second center, and the geometric center of the orthographic projection of the opening of the third pixel on the substrate is the third center. The third center is located on the side closer to the second center than the midpoint of the line connecting the first center and the second center.

12. The display substrate according to claim 11, wherein, The side of the third pixel opening away from the first sub-pixel along the second direction is substantially flush with the side of the second pixel opening away from the first sub-pixel along the first direction.

13. The display substrate according to any one of claims 1-10, wherein, In the first sub-pixel and the second sub-pixel adjacent along the second direction, and the third sub-pixel adjacent along the first direction, the geometric center of the orthographic projection of the opening of the first pixel on the substrate is the first center, the geometric center of the orthographic projection of the opening of the second pixel on the substrate is the second center, and the geometric center of the orthographic projection of the opening of the third pixel on the substrate is the third center. The third center is located on the side closer to the first center than the midpoint of the line connecting the first center and the second center.

14. The display substrate according to claim 13, wherein, The side of the third pixel opening away from the second sub-pixel along the second direction is substantially flush with the side of the first pixel opening away from the second sub-pixel along the first direction.

15. The display substrate according to any one of claims 1-14, wherein, The display substrate includes a driving circuit layer on the substrate and a light-emitting device layer on the side of the driving circuit layer away from the substrate. The driving circuit layer includes a source / drain metal layer closest to the light-emitting device layer. The source / drain metal layer includes a power signal line extending along the second direction. The orthographic projection of the third pixel opening on the substrate is located within the orthographic projection of the power signal line on the substrate.

16. The display substrate according to any one of claims 1-14, wherein, The display substrate includes a driving circuit layer on the substrate and a light-emitting device layer on the side of the driving circuit layer away from the substrate. The driving circuit layer includes a source / drain metal layer closest to the light-emitting device layer, and the source / drain metal layer includes data signal lines extending along the second direction. The orthographic projection of the third pixel opening on the substrate overlaps with the orthographic projection of the data signal line on the substrate, and the geometric center of the orthographic projection of the third pixel opening on the substrate is located within the orthographic projection of the data signal line on the substrate.

17. The display substrate according to any one of claims 1-14, wherein, The display substrate includes a driving circuit layer on the substrate and a light-emitting device layer on the side of the driving circuit layer away from the substrate. The driving circuit layer includes a source / drain metal layer closest to the light-emitting device layer. The source / drain metal layer includes a data signal line extending along the second direction and a blank trace extending along the second direction. The first part of the orthographic projection of the third pixel opening on the substrate overlaps with the orthographic projection of the data signal line on the substrate, and the second part of the orthographic projection of the third pixel opening on the substrate overlaps with the orthographic projection of the blank trace on the substrate. as well as The first part and the second part are located on both sides of the geometric center of the orthographic projection of the third pixel opening on the substrate along the first direction.

18. The display substrate according to any one of claims 1-14, wherein, The display substrate includes a driving circuit layer on the substrate and a light-emitting device layer on the side of the driving circuit layer away from the substrate. The driving circuit layer includes a source / drain metal layer closest to the light-emitting device layer. The source / drain metal layer includes multiple signal traces that extend along a second direction and are arranged along a first direction. The orthographic projection of the third pixel opening on the substrate is located between the orthographic projections of the two adjacent signal traces on the substrate.

19. A display device, wherein, The display device includes a display substrate according to any one of claims 1-18.

20. A photomask, wherein, The mask is used to fabricate a display substrate according to any one of claims 1-18, the mask comprising: A first sub-mask is used to create the first sub-pixel, and the first sub-mask includes a plurality of first openings arranged in an array. A second sub-mask, used to fabricate the second sub-pixel, the second sub-mask including a plurality of second openings arranged in an array; and A third sub-mask is used to create the third sub-pixel. The third sub-mask includes a plurality of third openings arranged in an array. The area of ​​the third opening is smaller than the area of ​​the first opening and the area of ​​the third opening is smaller than the area of ​​the second opening.

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