Pixel arrangement structure, display panel, driving method of display panel, display device and mask group

Abstract

The invention provides a pixel arrangement structure, a display panel, a driving method of the display panel, a display device and a mask group. The pixel arrangement structure comprises a plurality of basic pixel units which are arranged in an array mode, each basic pixel unit comprises a first sub-pixel, a second sub-pixel, a third sub-pixel and a fourth sub-pixel, and the first sub-pixel, the second sub-pixel and the third sub-pixel are sub-pixels of different colors. The third sub-pixel and the fourth sub-pixel are sub-pixels with the same color; one of the third sub-pixel and the fourth sub-pixel comprises a single light-emitting layer, the other one of the third sub-pixel and the fourth sub-pixel comprises at least two sub-light-emitting layers which are arranged in a laminated mode, and a charge generation layer is arranged between every two adjacent sub-light-emitting layers. According to the pixel arrangement structure, the problem of color cast of a white picture under low brightness after a reliability test is solved, and meanwhile, the problem of a dark field caused by extinguishment of some pixels can be eliminated, so that the display effect of the display panel is improved, and the yield and the product competitiveness of the display panel are improved.

Description

Technical Field

[0001] This invention generally relates to the field of display technology, and more specifically to a pixel arrangement structure, a display panel and its driving method, a display device and a mask assembly. Background Technology

[0002] With the increasing demand for high luminous efficiency in OLED devices, tandem light-emitting devices (LEDs) are widely used because their efficiency can be twice that of single-layer LEDs made of the same materials. In tandem LEDs, green light efficiency contributes the most to white light efficiency, making improving the efficiency of the green light material the most critical factor. However, excessively high green light material efficiency can also cause problems. For example, after the display undergoes environmental reliability testing (lighting up under high temperature and humidity), it can cause thin-film transistor (TFT) aging, leading to a shift in characteristics and potentially resulting in leakage current. Given the same leakage current, higher efficiency of the OLED device's light-emitting material results in higher brightness. This can cause a greenish tint to the white screen at low brightness levels after environmental reliability testing. Summary of the Invention

[0003] In view of the above-mentioned defects or deficiencies in the prior art, it is desirable to provide a pixel arrangement structure, a display panel and its driving method, a display device and a mask assembly. By setting sub-pixels of the same color as sub-pixels of a single light-emitting layer and sub-pixels of at least two stacked sub-light-emitting layers, it is beneficial to solve the color deviation phenomenon of white screen under low brightness after reliability testing. At the same time, it can also eliminate the dark field problem caused by some pixels being turned off, thereby improving the display effect of the display panel, increasing the yield of the display panel and the product competitiveness.

[0004] In a first aspect, the present invention provides a pixel arrangement structure, including a plurality of basic pixel units arranged in an array, each basic pixel unit including a first sub-pixel, a second sub-pixel, a third sub-pixel, and a fourth sub-pixel, wherein the first sub-pixel, the second sub-pixel, and the third sub-pixel are sub-pixels of different colors, and the third sub-pixel and the fourth sub-pixel are sub-pixels of the same color.

[0005] The third sub-pixel and the fourth sub-pixel, one of which includes a single light-emitting layer, and the other includes at least two sub-light-emitting layers stacked together, with a charge-generating layer disposed between adjacent sub-light-emitting layers.

[0006] As an alternative, the third and fourth sub-pixels are arranged side by side along the first or / and second direction, with the first and second directions perpendicular to each other.

[0007] As an optional solution, the third and fourth sub-pixels are set alternately.

[0008] As an alternative, the thickness of a single light-emitting layer is the same as the sum of the thicknesses of at least two sub-light-emitting layers in the stack.

[0009] As an optional scheme, the first sub-pixel is a red sub-pixel, the second sub-pixel is a blue sub-pixel, and the third and fourth sub-pixels are both green sub-pixels;

[0010] Alternatively, the first sub-pixel is a blue sub-pixel, the second sub-pixel is a red sub-pixel, and the third and fourth sub-pixels are both green sub-pixels.

[0011] As an optional scheme, the ratio of red sub-pixels, blue sub-pixels, and green sub-pixels is 1:1:4.

[0012] As an optional scheme, the ratio of the number of third sub-pixels to the number of fourth sub-pixels is 1:1.

[0013] As an alternative, the first sub-pixel, the second sub-pixel, and the third sub-pixel have the same shape but different areas.

[0014] As an alternative, the area of ​​the first sub-pixel is smaller than the area of ​​the second sub-pixel, and the sum of the areas of the third and fourth sub-pixels is greater than the area of ​​the second sub-pixel.

[0015] As an alternative, the third and fourth sub-pixels have the same shape and the same area.

[0016] In a second aspect, the present invention provides a display panel including the pixel arrangement structure of the first aspect.

[0017] Thirdly, the present invention provides a driving method for a display panel, used to drive the display panel of the second aspect to light up, the driving method comprising the following steps:

[0018] Acquire the input voltage signal;

[0019] Based on the frequency of the input voltage signal, control one of the third and fourth sub-pixels to light up and the other to turn off.

[0020] As an optional approach, based on the frequency of the input voltage signal, one of the third and fourth sub-pixels is controlled to light up while the other sub-pixel is turned off, including:

[0021] When the frequency of the input voltage signal is lower than a preset threshold, control one sub-pixel, which includes a single light-emitting layer, in the third and fourth sub-pixels to light up, and control another sub-pixel, which includes at least two sub-light-emitting layers stacked together, to turn off;

[0022] When the frequency of the input voltage is higher than or equal to a preset threshold, one sub-pixel in the third and fourth sub-pixels, which includes a single light-emitting layer, is turned off, and another sub-pixel, which includes at least two sub-light-emitting layers in a stacked configuration, is turned on.

[0023] Fourthly, the present invention provides a display device including the display panel of the third aspect.

[0024] Fifthly, the present invention provides a mask assembly for fabricating a pixel arrangement structure of the first aspect, comprising a first mask, a second mask, and a third mask, wherein the first mask has a plurality of first openings arranged in an array, the first openings being used to form a first sub-pixel; the second mask has a plurality of second openings arranged in an array, the second openings being used to form a second sub-pixel; and the third mask has a plurality of third openings arranged in an array, the third openings being used to form a third sub-pixel and a fourth sub-pixel.

[0025] As an alternative, the third opening can be arranged side-by-side or staggered in the first or second direction.

[0026] The pixel arrangement structure of the present invention includes a plurality of basic pixel units arranged in an array. Each basic pixel unit includes a first sub-pixel, a second sub-pixel, a third sub-pixel, and a fourth sub-pixel. The first sub-pixel, the second sub-pixel, and the third sub-pixel are sub-pixels of different colors, while the third sub-pixel and the fourth sub-pixel are sub-pixels of the same color. One of the third sub-pixel and the fourth sub-pixel includes a single light-emitting layer, and the other includes at least two sub-light-emitting layers stacked together. A charge-generating layer is disposed between two adjacent sub-light-emitting layers. Thus, by setting sub-pixels of the same color as sub-pixels of a single-layer emitting layer and sub-pixels of a stacked emitting layer respectively, it is beneficial to control one of the sub-pixels of the single-layer emitting layer and the other of the sub-pixels of the stacked emitting layer to be lit and the other to be off according to actual needs in actual use. This helps to eliminate the dark field problem that may be caused by some pixels being off. On the one hand, it is beneficial to solve the color deviation phenomenon of white screen under low brightness after reliability test by using the high capacitance of sub-pixels of the stacked structure, while ensuring that the light-emitting device has high luminous efficiency, which helps to improve the display effect of the display panel. On the other hand, the design of sub-pixels of the single-layer emitting layer and sub-pixels of the stacked emitting layer can also solve the problem of poor color mixing in the evaporation process, improve product quality, and thus improve the product quality and competitiveness of the display panel. Attached Figure Description

[0027] Other features, objectives, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0028] Figure 1 This is a cross-sectional schematic diagram of a single-layer display panel in the prior art;

[0029] Figure 2 This is a cross-sectional schematic diagram of a display panel with a stacked structure in the prior art;

[0030] Figure 3 This is a schematic diagram of a pixel arrangement structure according to an embodiment of this application;

[0031] Figure 4 for Figure 3 A cross-sectional schematic diagram of AA in the middle;

[0032] Figure 5 This is a schematic diagram of another pixel arrangement structure according to an embodiment of this application;

[0033] Figure 6 for Figure 5 Cross-sectional schematic diagram of BB;

[0034] Figure 7 This is a schematic diagram illustrating the structural principle of a display panel driving method according to an embodiment of this application.

[0035] Figure 8 This is a schematic diagram of the structure of the first mask in an embodiment of this application;

[0036] Figure 9 This is a schematic diagram of the structure of the second mask in an embodiment of this application;

[0037] Figure 10 This is a schematic diagram of the structure of a third mask according to an embodiment of this application;

[0038] Figure 11 This is a schematic diagram of the structure of another third mask in an embodiment of this application.

[0039] In the picture,

[0040] 100. Display panel;

[0041] 10. Basic pixel unit; 11. First sub-pixel; 12. Second sub-pixel; 13. Third sub-pixel; 14. Fourth sub-pixel;

[0042] 20. Substrate; 21. Anode layer; 22. Hole transport layer; 23. Light-emitting layer; 231. First sub-light-emitting layer; 232. Second sub-light-emitting layer; 24. Hole blocking layer; 25. Electron transport layer; 26. Cathode layer; 27. Encapsulation layer; 28. Pixel definition layer; 29. ​​Electron injection layer; 30. Hole injection layer.

[0043] 40. First mask; 41. First opening;

[0044] 50. Second mask; 51. Second opening;

[0045] 60. Third mask; 61. Third opening. Detailed Implementation

[0046] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0047] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0048] A stacked organic light-emitting diode (TOLED) is a device composed of two or more independent light-emitting units connected in series through a charge generation layer (CGL). The light emission of each unit does not affect the others, and compared to single-layer light-emitting devices, it can achieve higher brightness, higher current efficiency, and longer lifespan. Existing stacked device structures and single-layer device structures are as follows: Figure 1 and Figure 2 As shown, the light-emitting unit of the single-layer device structure includes an anode layer 21, a hole injection layer 30, a hole transport layer 22, a light-emitting layer 23, an electron transport layer 25, a hole blocking layer 24, an electron injection layer 29, and a cathode layer 26 stacked sequentially. The light-emitting unit of the multilayer device structure includes an anode layer 21, a hole injection layer 30, a hole transport layer 22, a first sub-light-emitting layer 231, an N-type charge generation layer, a P-type charge generation layer, a second sub-light-emitting layer 232, an electron transport layer 25, a hole blocking layer 24, an electron injection layer 29, and a cathode layer 26 stacked sequentially. In related technologies, the green light efficiency contributes the most to the white light efficiency in multilayer light-emitting devices; therefore, improving the efficiency of green light materials is the most critical factor. However, the high efficiency of green light materials can also cause some problems. For example, after the display undergoes environmental reliability testing (lighting up under high temperature and humidity), it can cause thin film transistors (TFTs) to age, resulting in a shift in characteristics. This may lead to leakage current. When the leakage current is the same, the higher the efficiency of the light-emitting material of the OLED device, the higher the brightness. This causes the white screen of the OLED display to appear greenish at low brightness after the environmental reliability test.

[0049] In view of the above problems, firstly, embodiments of this application provide a pixel arrangement structure, such as... Figure 3 and Figure 5As shown, it includes multiple basic pixel units 10 arranged in an array. Each basic pixel unit 10 includes a first sub-pixel 11, a second sub-pixel 12, a third sub-pixel 13, and a fourth sub-pixel 14. The first sub-pixel 11, the second sub-pixel 12, and the third sub-pixel 13 are sub-pixels of different colors, while the third sub-pixel 13 and the fourth sub-pixel 14 are sub-pixels of the same color.

[0050] The third sub-pixel 13 and the fourth sub-pixel 14, one of which includes a single light-emitting layer 23, and the other includes at least two sub-light-emitting layers stacked together, with charge generation layers disposed between adjacent sub-light-emitting layers.

[0051] It's understandable that OLED display panels are composed of multiple repeating pixel units. Each repeating pixel unit includes three types of sub-pixels: R sub-pixels (red sub-pixels), G sub-pixels (green sub-pixels), and B sub-pixels (blue sub-pixels). The more repeating pixel units arranged within a limited pixel area, the higher the PPI (Pixels Per Inch), and the better the display effect of the OLED display panel. Adjusting the structure of each sub-pixel, the corresponding aperture ratio, and the arrangement of the pixels can help improve the display effect of OLED and avoid display defects.

[0052] In the embodiments of this application, the basic pixel unit 10 is a repeating unit, and the basic pixel units 10 are distributed in an array, that is, the basic pixel units 10 can be repeatedly arranged in the first direction and / or the second direction. It should be noted that the number of basic pixel units 10 in the embodiments of this application is not limited. For example, the number of basic pixel units 10 in the first direction can be one, two, or more; the number of basic pixel units 10 in the second direction can be one, two, or more. The number of basic pixel units 10 in the first direction and the second direction can be equal or unequal, wherein the first direction can be the horizontal direction of the entire pixel arrangement structure (e.g., ...). Figure 3 The X direction in the image can be the first direction, and the second direction can be the vertical direction of the entire pixel arrangement (e.g., the X direction). Figure 3 (Y direction in the image), of course, in some other embodiments, the first direction and the second direction can also be the diagonal direction of the entire pixel arrangement structure.

[0053] It is understandable that the colors of the first sub-pixel 11, the second sub-pixel 12, and the third sub-pixel 13 are different, while the color of the third sub-pixel 13 and the fourth sub-pixel 14 are the same. That is, the color of the fourth sub-pixel 14 is different from the colors of the first sub-pixel 11 and the second sub-pixel 12. The third sub-pixel 13 and the fourth sub-pixel 14 can be red, green, or blue sub-pixels, depending on the actual needs of the product.

[0054] In this design, the third sub-pixel 13 may include a single light-emitting layer 23, and the fourth sub-pixel 14 may include at least two sub-light-emitting layers stacked together. A charge-generating layer is disposed between adjacent sub-light-emitting layers. That is, the third sub-pixel 13 is a single-layer sub-pixel, and the fourth sub-pixel 14 is a tandem sub-pixel. The luminous efficiency of the fourth sub-pixel 14 is higher than that of the third sub-pixel 13. Alternatively, the fourth sub-pixel 14 may include a single light-emitting layer 23, and the third sub-pixel 13 may include at least two stacked sub-light-emitting layers. A charge-generating layer is disposed between adjacent sub-light-emitting layers. In this case, the fourth sub-pixel 14 is a single-layer sub-pixel, and the luminous efficiency of the third sub-pixel 13 is higher than that of the fourth sub-pixel 14. It is also understood that since the color of the third sub-pixel 13 and the fourth sub-pixel 14 is the same, the materials of the light-emitting layer 23 and the sub-light-emitting layers can be the same or different. In a preferred embodiment, the light-emitting layer 23 and the sub-light-emitting layers are made of the same material, which facilitates processing.

[0055] In practical use, since single-layer subpixels and stacked subpixels each have different advantages, in the embodiments of this application, subpixels of the same color are set as single-layer subpixels and stacked subpixels. This is beneficial to control one of the third subpixel 13 and the fourth subpixel 14 to be lit and the other to be off, according to actual product requirements. For example, by controlling the single-layer subpixel to be off when the brightness requirement is low and on when the brightness requirement is high, and the stacked subpixel to be on when the brightness requirement is low and off when the brightness requirement is high, it can be used to improve color mixing problems. As another example, by controlling the single-layer subpixel to be on when the brightness requirement is low and off when the brightness requirement is high, and the stacked subpixel to be on when the brightness requirement is low and on when the brightness requirement is high, it can be used to improve luminous efficiency.

[0056] It is also understandable that in related technologies, when depositing sub-pixels in a stacked structure, the thickness of the sub-emitting layer in the stacked structure is halved compared to the thickness of the single-layer emitting layer 23. This results in lower photoluminescence brightness of the sub-emitting layer, which may cause misalignment when depositing the second sub-emitting layer, easily leading to poor color mixing. Alternatively, to avoid poor color mixing, it is necessary to improve the backlight module to ensure accurate alignment. In the embodiments of this application, sub-pixels of the same color are provided with both single-layer and stacked structures. Thus, when depositing the stacked structure, the single-layer sub-pixels can help improve the alignment of the second sub-emitting layer, thereby ensuring good color mixing.

[0057] It should be noted that the charge generation layer can include an N-type charge generation layer containing N-type dopant and a P-type charge generation layer containing P-type dopant. The N-type charge generation layer is mainly used to generate electrons under the influence of an applied electric field, while the P-type charge generation layer is mainly used to generate holes under the influence of an applied electric field. In this way, the electrons and holes generated by the charge generation layer combine with holes injected from the anode and electrons injected from the cathode, respectively, in the light-emitting layer to emit light, enabling the light-emitting device to achieve high brightness, high efficiency, and long lifetime at low current densities. For example, such as... Figure 4 As shown, the third sub-pixel 13 includes two sub-light-emitting layers stacked together, with a charge-generating layer disposed between the two sub-light-emitting layers. Holes generated by the charge-generating layer and moving towards the cathode recombine with electrons provided by the cathode in the first sub-light-emitting layer located on the cathode side of the charge-generating layer to form excitons, causing the first sub-light-emitting layer to emit light. Electrons generated by the charge-generating layer and moving towards the anode recombine with holes provided by the anode in the second sub-light-emitting layer located on the anode side of the charge-generating layer to form excitons, causing the second sub-light-emitting layer to emit light. This achieves sub-pixel light emission in a stacked structure.

[0058] The pixel arrangement structure of this application solves the color shift problem of white screen after OLED reliability testing in the prior art. The pixel arrangement structure of this application, by setting sub-pixels of the same color as sub-pixels of a single-layer light-emitting layer 23 and sub-pixels of a stacked sub-light-emitting layer respectively, facilitates the control of one sub-pixel of the single-layer light-emitting layer 23 and the other sub-pixel of the stacked sub-light-emitting layer to be lit and the other off according to actual needs in practical use. This helps to eliminate the dark field problem that may be caused by some pixels being off. Furthermore, on the one hand, it helps to solve the color shift phenomenon of white screen under low brightness after reliability testing by utilizing the high capacitance of the sub-pixels of the stacked structure, while ensuring that the light-emitting device has high luminous efficiency, which is beneficial to improving the display effect of the display panel. On the other hand, the sub-pixels of the single-layer light-emitting layer 23 and the sub-pixels of the stacked sub-light-emitting layer can also solve the problem of poor color mixing during the evaporation process, improve product quality, and thus improve the product quality and competitiveness of the display panel.

[0059] As an implementation, the third sub-pixel 13 and the fourth sub-pixel 14 are arranged side by side along a first direction or / and a second direction, with the first direction and the second direction being perpendicular.

[0060] The first direction and the second direction are as described above. The first direction can be the horizontal direction of the entire pixel arrangement structure (e.g., Figure 3 The X direction in the image can be the first direction, and the second direction can be the vertical direction of the entire pixel arrangement (e.g., the X direction). Figure 3 Y direction in ).

[0061] The number of third sub-pixels 13 and fourth sub-pixels 14 can each be one, two, or more. Of course, the specific number is determined according to the actual product requirements and the actual processing technology; for example, there can be two third sub-pixels 13 and two fourth sub-pixels 14.

[0062] The arrangement of the third sub-pixel 13 and the fourth sub-pixel 14 in the first or second direction can be understood as the third sub-pixel 13 and the fourth sub-pixel 14 being arranged in the horizontal direction of the entire pixel arrangement structure, or the third sub-pixel 13 and the fourth sub-pixel 14 being arranged in the vertical direction of the entire pixel arrangement structure.

[0063] In this embodiment, the arrangement of the third sub-pixel 13 and the fourth sub-pixel 14 is simple in structure and easy to process, which helps to reduce process requirements and save processing costs.

[0064] As a feasible approach, such as Figure 5 As shown, the third sub-pixel 13 and the fourth sub-pixel 14 are staggered.

[0065] It is understandable that the staggered setting of the third sub-pixel 13 and the fourth sub-pixel 14 refers to the third sub-pixel 13 and the fourth sub-pixel 14 being located in different rows or different columns in the first or second direction. For example, as... Figure 5 As shown, along the first direction, the third sub-pixel 13 is located in the first column, and the fourth sub-pixel 14 is located in the second column. Of course, it is also possible that along the first direction, the third sub-pixel 13 is located in the second column, and the fourth sub-pixel 14 is located in the first column.

[0066] In some embodiments, the thickness of a single light-emitting layer 23 is the same as the sum of the thicknesses of at least two sub-light-emitting layers 23 stacked together.

[0067] This embodiment facilitates the processing of the third sub-pixel 13 and the fourth sub-pixel 14, while improving the luminous efficiency of the light-emitting device and avoiding problems such as color mixing and color deviation.

[0068] In some embodiments, the first sub-pixel 11 is a red sub-pixel, the second sub-pixel 12 is a blue sub-pixel, and the third sub-pixel 13 and the fourth sub-pixel 14 are all green sub-pixels.

[0069] In some other embodiments, the first sub-pixel 11 is a blue sub-pixel, the second sub-pixel 12 is a red sub-pixel, and the third sub-pixel 13 and the fourth sub-pixel 14 are all green sub-pixels.

[0070] In this embodiment, both the third sub-pixel 13 and the fourth sub-pixel 14 are green sub-pixels. By changing the pixel structure and arrangement of the green sub-pixels, it is beneficial to solve the color shift phenomenon of white screen under low brightness after the reliability test of the display panel, and it can also eliminate the dark field problem caused by some pixels being turned off.

[0071] As an feasible approach, the ratio of red sub-pixels, blue sub-pixels, and green sub-pixels is 1:1:4.

[0072] Among them, the number of third sub-pixels 13 and the number of fourth sub-pixels 14 corresponding to the green sub-pixels can be equal or unequal.

[0073] In this embodiment, the number of red, blue, and green sub-pixels can reliably solve the problem of white screen color deviation at low brightness after reliability testing by illuminating some of the green sub-pixels, and at the same time, achieve uniformity of low grayscale image quality, which is conducive to ensuring that the light-emitting device has a good display effect.

[0074] In a preferred embodiment, the ratio of the number of third sub-pixels 13 to the number of fourth sub-pixels 14 is 1:1.

[0075] In this embodiment, the number of third sub-pixels 13 and fourth sub-pixels 14 is equal, that is, the number of single-layer structure sub-pixels and stacked structure sub-pixels of the same color is equal. This helps to ensure the luminous efficiency of the light-emitting device, and at the same time solves the color mixing problem of the light-emitting device and the color deviation problem of the white screen under low brightness after the reliability test.

[0076] As a result, the first sub-pixel 11, the second sub-pixel 12, and the third sub-pixel 13 have the same shape but different areas.

[0077] The shapes of the first sub-pixel 11, the second sub-pixel 12, and the third sub-pixel 13 refer to the shapes of their respective orthographic projections (e.g., in a display panel, these could be the shapes of their respective orthographic projections on the substrate 20); similarly, the areas of the first sub-pixel 11, the second sub-pixel 12, and the third sub-pixel 13 refer to the areas of their respective orthographic projections (e.g., in a display panel, these could be the shapes of their respective orthographic projections on the substrate 20).

[0078] It is understandable that the first sub-pixel 11, the second sub-pixel 12, and the third sub-pixel 13 can be, but are not limited to, rectangles, rounded rectangles, ellipses, circles, etc. Of course, the shape and area of ​​the third sub-pixel 13 can be the same as or different from the shape and area of ​​the fourth sub-pixel 14.

[0079] This implementation method facilitates the processing of each sub-pixel, ensures luminous efficiency, and guarantees that each sub-pixel has a high luminous lifetime.

[0080] In some embodiments, the area of ​​the first sub-pixel 11 is smaller than the area of ​​the second sub-pixel 12, and the sum of the areas of the third sub-pixel 13 and the fourth sub-pixel 14 is greater than the area of ​​the second sub-pixel 12.

[0081] For example, the first sub-pixel 11 is a red sub-pixel, the second sub-pixel 12 is a blue sub-pixel, and the third sub-pixel 13 and the fourth sub-pixel 14 are green sub-pixels. In this embodiment, the area of ​​the second sub-pixel 12 is larger than that of the first sub-pixel 11, and the sum of the areas of the third sub-pixel 13 and the fourth sub-pixel 14 is larger than that of the second sub-pixel 12. This is beneficial for sub-pixel rendering, thereby improving the display effect of the display panel. Furthermore, the large area of ​​the blue sub-pixel can result in a low current density passing through the blue sub-pixel, thereby reducing the lifespan decay of the blue sub-pixel.

[0082] In some embodiments, the third sub-pixel 13 and the fourth sub-pixel 14 have the same shape and the same area.

[0083] In this embodiment, sub-pixels of the same color have the same shape and area, which helps to ensure the light emission effect of sub-pixels of the same color, and the same mask can be used to prepare sub-pixels, which is convenient to process and helps to improve production efficiency.

[0084] For example, both the third sub-pixel 13 and the fourth sub-pixel 14 are rounded rectangles, and the areas of the third sub-pixel 13 and the fourth sub-pixel 14 can be processed using the same mask.

[0085] In summary, the pixel arrangement structure in the embodiments of this application, by setting sub-pixels of the same color as sub-pixels of the single-layer light-emitting layer 23 and sub-pixels of the stacked sub-light-emitting layer respectively, is beneficial in actual use to control one of the sub-pixels of the single-layer light-emitting layer 23 and the sub-pixels of the stacked sub-light-emitting layer to be lit and the other to be off according to actual needs. This helps to eliminate the dark field problem that may be caused by some pixels being off. On the one hand, it helps to solve the white screen color deviation phenomenon under low brightness after reliability testing by using the high capacitance of the sub-pixels of the stacked structure, while ensuring that the light-emitting device has high luminous efficiency, which is beneficial to improving the display effect of the display panel. On the other hand, the sub-pixels of the single-layer light-emitting layer 23 and the sub-pixels of the stacked sub-light-emitting layer can also solve the problem of poor color mixing in the evaporation process, improve product quality, and thus improve the product quality and competitiveness of the display panel.

[0086] Furthermore, the third sub-pixel 13 and the fourth sub-pixel 14 can be set side by side or staggered, which is flexible and helps to reduce process requirements and save processing costs.

[0087] Secondly, embodiments of this application provide a display panel 100, including the pixel arrangement structure of the first aspect. It is understood that this display panel possesses all the features and advantages of the aforementioned pixel arrangement structure, which will not be repeated here. In summary, this display panel has high quality and yield, and excellent display performance.

[0088] Example 1

[0089] like Figure 3 As shown, the display panel includes multiple arrayed basic pixel units 10, each basic pixel unit 10 including a first sub-pixel 11, a second sub-pixel 12, two third sub-pixels 13, and two fourth sub-pixels 14. A cross-sectional view along the first direction is shown below. Figure 4 As shown, the display panel includes: a substrate 20, a driving layer disposed on the substrate 20, and a pixel definition layer 28 disposed on the side of the driving layer away from the substrate 20. The pixel definition layer 28 defines pixel opening areas. Each pixel opening area has an anode layer 21, a hole transport layer 22 (HTL), a light-emitting layer 23 (EML), a hole blocking layer 24 (HBL), an electron transport layer 25 (ETL), and a cathode layer 26 (CA) formed on one side away from the substrate 20. An encapsulation layer 27 is disposed on the side of the cathode layer 26 away from the substrate 20. The third sub-pixel 13 includes a first sub-light-emitting layer 231 and a second sub-light-emitting layer 232 stacked together. That is, the third sub-pixel 13 includes an anode layer 21, a hole transport layer 22, a first sub-light-emitting layer 231, a hole blocking layer 24, an N-type charge generation layer, a P-type charge generation layer, a second sub-light-emitting layer 232, a hole blocking layer 24, an electron transport layer 25, and a cathode layer 26 disposed on the side away from the substrate 20.

[0090] Example 2

[0091] The difference between this embodiment and Embodiment 1 is that, in this embodiment, as... Figure 5 As shown, the third sub-pixel 13 and the fourth sub-pixel 14 are arranged alternately, that is, the third sub-pixel 13 is located at the position of the first row and first column and the position of the second row and second column along the first direction, respectively, and the fourth sub-pixel 14 is located at the position of the first row and second column and the position of the second row and first column along the first direction, respectively. The cross-sectional structure of the display panel along the second direction is as follows. Figure 6 As shown, the structures of the third sub-pixel 13 and the fourth sub-pixel 14 are the same as in Embodiment 1.

[0092] Thirdly, embodiments of this application provide a driving method for a display panel, used to drive the display panel of the second aspect to light up, the driving method including the following steps:

[0093] Step S10: Acquire the input voltage signal;

[0094] Step S20: Based on the frequency of the input voltage signal, control one of the third sub-pixel 13 and the fourth sub-pixel 14 to light up and the other sub-pixel to turn off.

[0095] It is understood that the display panel driving method of the embodiments of this application can be executed by the display panel control system. The first sub-pixel 11, the second sub-pixel 12, the third sub-pixel 13 and the fourth sub-pixel 14 are each connected to the pixel driving circuit. The control system is signal-connected to the pixel driving circuit. The control system acquires the input voltage signal and outputs a signal to the pixel driving circuit using the GOA circuit according to the frequency of the input voltage signal, thereby controlling one of the third sub-pixel 13 and the fourth sub-pixel 14 to light up and the other to turn off.

[0096] In some embodiments, depending on actual needs, one of the third sub-pixel 13 and the fourth sub-pixel 14 is determined to be lit at low brightness and turned off at high brightness. The third sub-pixel 13 and the fourth sub-pixel 14 are programmed together with the first sub-pixel 11 and the second sub-pixel 12 with two sets of gamma curves, corresponding to high brightness and low brightness respectively. The dividing line between high brightness and low brightness can be 90 nits. Thus, according to different needs, the control system outputs a GOA signal to the pixel driving circuit based on the frequency of the acquired input voltage signal. The pixel driving circuit controls one of the third sub-pixel 13 and the fourth sub-pixel 14 to be lit and the other to be turned off.

[0097] like Figure 7As shown, based on the input voltage signal, the GOA output voltage signal is sent to the driving circuit to control one of the third sub-pixel 13 and the fourth sub-pixel 14 to light up and the other to turn off, while simultaneously serving as the input signal for the next layer, thus passing down layer by layer. For example, to improve the color cast issue of white images at low brightness after product reliability testing, the GOA output voltage signal can be used to control the sub-pixel circuits in the third sub-pixel 13 and the fourth sub-pixel 14 that include stacked structures to light up below 90 nits, and the sub-pixels that include single-layer structures to light up above 90 nits, or vice versa, to ensure uniformity of low grayscale image quality, the GOA output voltage signal can be used to control the sub-pixels in the third sub-pixel 13 and the fourth sub-pixel 14 that include stacked structures to light up above 90 nits, and the sub-pixels that include single-layer structures to light up below 90 nits, thus contributing to higher product brightness.

[0098] As an achievable method, step S20, based on the frequency of the input voltage signal, controls one of the third sub-pixel 13 and the fourth sub-pixel 14 to light up and the other sub-pixel to turn off, including:

[0099] When the frequency of the input voltage signal is lower than a preset threshold, control one sub-pixel in the third sub-pixel 13 and the fourth sub-pixel 14, which includes a single light-emitting layer 23, to light up, and control another sub-pixel, which includes at least two sub-light-emitting layers stacked together, to turn off;

[0100] When the frequency of the input voltage is higher than or equal to a preset threshold, one sub-pixel including a single light-emitting layer 23 in the third sub-pixel 13 and the fourth sub-pixel 14 is turned off, and another sub-pixel including at least two sub-light-emitting layers in a stacked configuration is turned on.

[0101] The preset threshold is determined in advance according to actual needs, such as, but not limited to, 50Hz.

[0102] In this embodiment, by controlling the sub-pixels including the stacked structure in the third sub-pixel 13 and the fourth sub-pixel 14 to light up under high-frequency voltage signals, and controlling the sub-pixels including the single-layer structure to light up under low-frequency voltage signals, and ensuring that only one sub-pixel in the third sub-pixel 13 and the fourth sub-pixel 14 lights up at a time while the other sub-pixel turns off, it is beneficial to solve the color shift problem of white screen under low brightness after reliability testing, and also beneficial to the display panel having high luminous efficiency.

[0103] In some other embodiments, step S20, controlling one of the third sub-pixel 13 and the fourth sub-pixel 14 to light up and the other sub-pixel to turn off based on the frequency of the input voltage signal, includes:

[0104] When the frequency of the input voltage signal is lower than or equal to a preset threshold, control one sub-pixel in the third sub-pixel 13 and the fourth sub-pixel 14, which includes a single light-emitting layer 23, to light up, and control another sub-pixel, which includes at least two sub-light-emitting layers stacked together, to turn off;

[0105] When the frequency of the input voltage is higher than a preset threshold, one sub-pixel including a single light-emitting layer 23 in the third sub-pixel 13 and the fourth sub-pixel 14 is turned off, and another sub-pixel including at least two sub-light-emitting layers in a stacked configuration is turned on.

[0106] Fourthly, the present invention provides a display device including the display panel of the third aspect. It is understood that this display device possesses all the features and advantages of the aforementioned display panel, which will not be repeated here. In summary, this display device has high quality and yield, and excellent display effect.

[0107] A display device is a product with image display capabilities. For example, a display device can be any of the following: monitor, television, billboard, digital photo frame, laser printer with display capabilities, telephone, mobile phone, personal digital assistant (PDA), digital camera, portable camcorder, viewfinder, navigator, vehicle, large-area wall display, home appliance, information query equipment (such as business query equipment for e-government, banks, hospitals, power companies, etc.), monitor, etc. A display device can also be a microdisplay or a product containing a microdisplay. Products containing microdisplays can be any of the following: smartwatch, smart bracelet, helmet display, stereoscopic display, and AR devices (such as AR glasses), VR devices (such as VR glasses), etc. For example, a microdisplay can be a display with a display size ranging from approximately 0.2 inches to approximately 2.5 inches, but is not limited to this. Understandably, a microdisplay can also be a display with a smaller display size, such as a display size less than or equal to 0.2 inches.

[0108] Fifthly, such as Figure 8-11 As shown, an embodiment of this application provides a mask group for fabricating a pixel arrangement structure in the first aspect, including a first mask 40, a second mask 50, and a third mask 60. The first mask 40 has a plurality of first openings 41 arranged in an array, which are used to form a first sub-pixel 11. The second mask 50 has a plurality of second openings 51 arranged in an array, which are used to form a second sub-pixel 12. The third mask 60 has a plurality of third openings 61 arranged in an array, which are used to form a third sub-pixel 13 and a fourth sub-pixel 14.

[0109] It is understood that the first mask 40 and the second mask 50 respectively fabricate the first sub-pixel 11 and the second sub-pixel 12 by vapor deposition, and the third mask 60 can fabricate the third sub-pixel 13 and the fourth sub-pixel 14 by vapor deposition, thereby obtaining the pixel arrangement structure of the embodiment of this application.

[0110] It should be noted that the third sub-pixel 13 and the fourth sub-pixel 14 can share a third opening 61. Of course, the third opening 61 can also include openings for the third sub-pixel 13 and the fourth sub-pixel 14 respectively, depending on the actual processing technology.

[0111] Among them, the first mask 40, the second mask, and the third mask 60 are precision metal masks. In the fabrication of the display panel, organic light-emitting materials of different colors are deposited to form corresponding sub-pixels. The third sub-pixel 13 and the fourth sub-pixel 14 are formed by depositing single-layer light-emitting materials and stacked light-emitting materials through the third opening 61, respectively. In addition, the shape and area of ​​the first opening 41, the second opening 51, and the third opening 61 are the same as the shape and area of ​​the first sub-pixel 11, the second sub-pixel 12, the third sub-pixel, and the fourth sub-pixel 14. The larger the opening, the lower the current density of the corresponding sub-pixel, which is beneficial to improving the lifespan of the display panel. The smaller the opening, the smaller the area of ​​a single sub-pixel, which is beneficial to improving the resolution of the display panel.

[0112] In some embodiments, the third openings 61 are arranged side-by-side or staggered in the first or second direction.

[0113] In this embodiment, the arrangement of the third opening 61 is conducive to forming different arrangements of the third sub-pixel 13 and the fourth sub-pixel 14.

[0114] It should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., used above to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the panel or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the invention, unless otherwise stated, "a plurality of" means two or more.

[0115] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A pixel arrangement structure, characterized in that, It includes multiple basic pixel units arranged in an array, each of the basic pixel units including a first sub-pixel, a second sub-pixel, a third sub-pixel, and a fourth sub-pixel, wherein the first sub-pixel, the second sub-pixel, and the third sub-pixel are sub-pixels of different colors, and the third sub-pixel and the fourth sub-pixel are sub-pixels of the same color; The third sub-pixel and the fourth sub-pixel, one of which includes a single light-emitting layer, and the other includes at least two sub-light-emitting layers stacked together, with a charge-generating layer disposed between two adjacent sub-light-emitting layers.

2. The pixel arrangement structure according to claim 1, characterized in that, The third sub-pixel and the fourth sub-pixel are arranged side by side along a first direction or / and a second direction, wherein the first direction and the second direction are perpendicular.

3. The pixel arrangement structure according to claim 1, characterized in that, The positions of the third sub-pixel and the fourth sub-pixel are staggered.

4. The pixel arrangement structure according to claim 1, characterized in that, The thickness of a single light-emitting layer is the same as the sum of the thicknesses of the at least two sub-light-emitting layers stacked together.

5. The pixel arrangement structure according to any one of claims 1-4, characterized in that, The first sub-pixel is a red sub-pixel, the second sub-pixel is a blue sub-pixel, and the third and fourth sub-pixels are both green sub-pixels; Alternatively, the first sub-pixel may be a blue sub-pixel, the second sub-pixel a red sub-pixel, and the third and fourth sub-pixels may both be green sub-pixels.

6. The pixel arrangement structure according to claim 5, characterized in that, The ratio of the number of red sub-pixels, blue sub-pixels, and green sub-pixels is 1:1:

4.

7. The pixel arrangement structure according to claim 6, characterized in that, The ratio of the number of the third sub-pixel to the number of the fourth sub-pixel is 1:

1.

8. The pixel arrangement structure according to any one of claims 1-4, characterized in that, The first sub-pixel, the second sub-pixel, and the third sub-pixel have the same shape but different areas.

9. The pixel arrangement structure according to claim 8, characterized in that, The area of ​​the first sub-pixel is smaller than the area of ​​the second sub-pixel, and the sum of the areas of the third and fourth sub-pixels is greater than the area of ​​the second sub-pixel.

10. The pixel arrangement structure according to any one of claims 1-4, characterized in that, The third sub-pixel and the fourth sub-pixel have the same shape and the same area.

11. A display panel, characterized in that, Includes the pixel arrangement structure as described in any one of claims 1-10.

12. A driving method for a display panel, characterized in that, The driving method for illuminating the display panel according to claim 11 includes the following steps: Acquire the input voltage signal; Based on the frequency of the input voltage signal, control one of the third and fourth sub-pixels to light up and the other sub-pixel to turn off.

13. The driving method according to claim 12, characterized in that, Based on the input voltage signal, controlling one of the third and fourth sub-pixels to light up and the other sub-pixel to turn off includes: When the frequency of the input voltage signal is lower than a preset threshold, one sub-pixel including a single light-emitting layer in the third and fourth sub-pixels is controlled to light up, and another sub-pixel including at least two sub-light-emitting layers stacked together is controlled to turn off. When the frequency of the input voltage is higher than or equal to a preset threshold, one sub-pixel including a single light-emitting layer in the third and fourth sub-pixels is turned off, and another sub-pixel including at least two sub-light-emitting layers in a stacked configuration is turned on.

14. A display device, characterized in that, Includes the display panel as described in claim 11.

15. A mask assembly for fabricating the pixel arrangement structure according to any one of claims 1-10, characterized in that, The mask includes a first mask, a second mask, and a third mask. The first mask has multiple first openings arranged in an array, which are used to form the first sub-pixel. The second mask has multiple second openings arranged in an array, which are used to form the second sub-pixel. The third mask has multiple third openings arranged in an array, which are used to form the third sub-pixel and the fourth sub-pixel.

16. The photomask assembly according to claim 15, characterized in that, The third opening is arranged side-by-side or staggered in the first direction or the second direction.

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