Microstructure layer and display device

Abstract

The present application provides a microstructure layer and a display device. The microstructure layer comprises a first refraction layer and a second refraction layer that are arranged in a first direction and have different refractive indexes. In addition, imprints and fillers that are alternately arranged in a second direction and also have different refractive indexes are arranged at the junction of the first refraction layer and the second refraction layer. By enabling the microstructure layer to comprise a first refraction layer and a second refraction layer that have different refractive indexes, and providing, at the junction of the first refraction layer and the second refraction layer, imprints and fillers that are alternately arranged, the dependence of luminescent spectrums on viewing angle changes can be reduced, thereby ameliorating color shift phenomena at large viewing angles, so that the color shift of a display device under an oblique viewing angle can be ameliorated.

Description

Microstructure layer and display device

[0001] This disclosure claims priority to Chinese patent application No. 202311740269.9, filed on December 18, 2023, and entitled “Microstructure Layer and Display Device,” the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present application relates to the field of display technology, and in particular to a microstructure layer and a display device. Background Art

[0003] Of all the human sensory organs, the eyes, as the visual organ, receive the most information. In production and daily life, people increasingly rely on rich visual information, and therefore display technology plays a crucial role in today's human society. Since its emergence, display technology has developed rapidly. With the development of society and the continuous improvement of people's material needs, today's display technology is rapidly moving towards high contrast, high resolution, full color display, low power consumption, high reliability, long life, and lightweight and thin design.

[0004] Among them, Organic Light-Emitting Diode (OLED) display devices have attracted increasing attention due to their advantages such as self-luminescence, fast response speed, wide visual range, high definition, high brightness, strong bending resistance and low power consumption. They are also known as the next generation of dream display technology.

[0005] Summary of the Invention

[0006] In view of the above problems, the embodiments of the present application provide a microstructure layer and a display device, and the solutions are as follows:

[0007] The first aspect of the present application provides a microstructure layer, comprising a first refractive layer and a second refractive layer arranged along a first direction, the first refractive layer and the second refractive layer having different refractive indices; an embossing and a filler are provided at the junction of the first refractive layer and the second refractive layer, and the embossing and the filler are spaced apart in a second direction, and the second direction is perpendicular to the first direction; wherein the refractive index of the embossing is different from that of the first refractive layer, or the refractive index of the embossing is the same as that of the second refractive layer, and the refractive index of the filler is the same as that of the first refractive layer, or the refractive index of the filler is the same as that of the second refractive layer, and the refractive index of the embossing is different from that of the filler.

[0008] In an embodiment of the present application, the microstructure layer includes a first refractive layer and a second refractive layer having different refractive indices, and an embossing and a filler are formed at the junction of the first and second refractive layers, spaced apart in a second direction. The refractive index of the embossing is consistent with that of the first or second refractive layer, and the refractive index of the filler is also consistent with that of the first or second refractive layer, but the refractive indices of the embossing and the filler are different. By providing a microstructure layer including first and second refractive layers having different refractive indices and spaced apart embossing and filler at their junction, the dependence of the luminous spectrum on viewing angle changes can be reduced, thereby improving color shift at wide viewing angles.

[0009] In a possible implementation, the refractive index of the first refractive layer is 1.45-1.9, and the refractive index of the second refractive layer is 1.3-1.6.

[0010] In this embodiment, the refractive index of the first refractive layer is limited to 1.45-1.9, and the refractive index of the second refractive layer is limited to 1.3-1.6, which also limits the refractive index of the stamped and filled components. Maintaining the refractive index within this range can redirect the outgoing light path, redistributing the viewing angle light into a new spectrum. The newly formed spectral morphology is closer to the peak appearance at normal viewing angles, further improving color shift at wide viewing angles.

[0011] In a possible implementation manner, a ratio of a size of the embossing in the first direction to a size of the embossing in the second direction is greater than or equal to 1.4.

[0012] In the embodiments of this application, the embossing dimension in the first direction is the height, and the dimension in the second direction is the width. The aspect ratio design of the embossing in the microstructure layer significantly affects color improvement. A larger aspect ratio increases color improvement efficiency and improves color shift at wide viewing angles. By setting the ratio of the embossing dimension in the first direction to that in the second direction to be greater than or equal to 1.4, color shift at oblique viewing angles can be further improved.

[0013] In a possible implementation, the stamp has an intaglio pattern, and the ratio of the area of ​​the intaglio pattern to the area of ​​the stamp is greater than or equal to 0.35.

[0014] In the embodiments of this application, the density of the pattern on the embossing significantly affects the color improvement rate. Generally speaking, the higher the density of the pattern on the embossing, the greater the proportion of components involved in the light path refraction, the greater the degree of adjustment to the light path, and thus the relatively better improvement in color difference. Therefore, by ensuring that the intaglio pattern accounts for no less than 35% of the area on the embossing, the color shift phenomenon at oblique viewing angles can be further improved.

[0015] In a possible implementation manner, the embossed shape includes at least one of a rectangle, a trapezoid, a triangle, and an ellipse.

[0016] In a possible implementation, the microstructure layer includes a plurality of first refractive layers and a plurality of second refractive layers; in the first direction, the plurality of first refractive layers and the plurality of second refractive layers are arranged at intervals.

[0017] In the embodiment of the present application, the first refractive layer and the second refractive layer in the microstructure layer can have multiple layers, and the first refractive layer and the second refractive layer can be stacked in different stacking methods. In this way, the microstructure layer can be installed according to assembly requirements, which helps to improve the flexibility of installing the microstructure layer.

[0018] In one possible embodiment, the microstructure layer further includes a first substrate; in the first direction, the first substrate is arranged on one side of the first refractive layer and the second refractive layer, and the material of the first substrate includes at least one of triacetyl cellulose, polyethylene terephthalate, ultra-thin flexible glass, transparent polyimide, polymethyl methacrylate or cycloolefin polymer.

[0019] In the embodiment of the present application, a first substrate is provided in the microstructure layer and is provided on one side of the first refractive layer and the second refractive layer, for example, the first substrate is provided above the first refractive layer and the second refractive layer, so as to support the microstructure layer.

[0020] The second aspect of the present application provides a display device, which comprises the microstructure layer described in any embodiment of the first aspect of the present application; the display device includes a base substrate, a driving circuit layer located on one side of the base substrate, an electroluminescent layer located on a side of the driving circuit layer away from the base substrate, and the microstructure layer located on a side of the electroluminescent layer away from the base substrate.

[0021] In a possible implementation, the display device further includes a black matrix, and the black matrix is ​​disposed on a side of the microstructure layer close to the base substrate.

[0022] In an embodiment of the present application, the microstructure layer is arranged on the side of the black matrix close to the base substrate, for example, the microstructure layer is arranged below the black matrix, which can reduce the dependence of the luminous spectrum on the viewing angle change, thereby improving the color cast phenomenon.

[0023] In a possible embodiment, the display device further includes a cover plate and a composite circular polarizer, the cover plate being located on a side of the composite circular polarizer away from the base substrate; wherein the microstructure layer is located on a side of the cover plate away from the base substrate; or the microstructure layer is located between the cover plate and the composite circular polarizer; or the microstructure layer is located on a side of the composite circular polarizer close to the base substrate.

[0024] In one possible embodiment, when the microstructure layer is located between the cover plate and the composite circular polarizer, the microstructure layer is located in a first area corresponding to the opening area of ​​the black matrix, or the microstructure layer is located in a second area corresponding to the non-opening area of ​​the black matrix.

[0025] In the embodiment of the present application, a microstructure layer is provided in the display device to improve color shift at oblique viewing angles. There are multiple options for the position of the microstructure layer, so that the position of the microstructure layer can be selected according to the actual production process.

[0026] In one possible embodiment, the composite circular polarizer includes a circular polarizer body and a brightness enhancing film, and the brightness enhancing film is located on the side of the circular polarizer body close to the base substrate; wherein the material of the brightness enhancing film includes cholesteric liquid crystal, and the central wavelength of the reflected light spectrum of the brightness enhancing film is 450nm-480nm.

[0027] In the embodiment of the present application, the center wavelength of the reflected light spectrum of the brightness enhancement film is 450nm-480nm, that is, the brightness enhancement film is a blue light brightness enhancement film. The principle of blue light anti-reflection is that when the display panel emits blue light, when it encounters the brightness enhancement film made of cholesteric liquid crystal, the panel output light can be decomposed into about 50% right-handed light and about 50% left-handed light; 50% of the right-handed light penetrates the brightness enhancement film and normally exits the display module, and 50% of the left-handed light is reflected back to the panel, and after reflection from the panel, it becomes right-handed light, and then penetrates the brightness enhancement film and exits the display module. Therefore, by arranging a brightness enhancement film made of cholesteric liquid crystal and having a reflection center wavelength of 450nm-480nm under the circular polarizer body, that is, combining the circular polarizer body and the brightness enhancement film as a composite circular polarizer, and acting in the display device, the light extraction efficiency of blue light can be improved, thereby improving the color cast of the display device at an oblique viewing angle, and also improving the brightness decay rate at an oblique viewing angle.

[0028] In a possible implementation, the half-peak width of the reflected light spectrum of the brightness enhancement film is 5 nm-80 nm.

[0029] In the embodiment of the present application, by making the half-peak width of the reflected light spectrum of the brightness enhancement film be 5nm-80nm, the brightness of the light output can be further increased, the reflectivity can be reduced, and the dark state can be reduced.

[0030] In a possible implementation manner, the thickness of the brightness enhancement film is less than or equal to 5 um.

[0031] In the embodiment of the present application, if the thickness of the brightness enhancement film is too high, it is not conducive to spectral emission and bending of the display device. Therefore, the thickness of the brightness enhancement film is maintained at no more than 5 μm.

[0032] In one possible embodiment, the circular polarizer body includes a first substrate, a linear polarizer, a half-wave plate film layer, and a quarter-wave plate film layer, which are arranged in sequence along a direction close to the substrate; wherein, the angle between the absorption axis direction of the linear polarizer and the slow axis direction of the half-wave plate film layer is 15°, and the angle between the absorption axis direction of the linear polarizer and the slow axis direction of the quarter-wave plate film layer is 75°; or the angle between the absorption axis direction of the linear polarizer and the slow axis direction of the half-wave plate film layer is 105° or 285°, and the angle between the absorption axis direction of the linear polarizer and the slow axis direction of the quarter-wave plate film layer is 165° or 345°.

[0033] In an embodiment of the present application, by setting the angle between the absorption axis of the linear polarizer and the slow axis of the half-wave plate film layer to 15°, and the angle between the absorption axis of the linear polarizer and the slow axis of the quarter-wave plate film layer to 75°, the brightness enhancement film is a left-handed cholesteric liquid crystal. By setting the angle between the absorption axis of the linear polarizer and the slow axis of the half-wave plate film layer to 105° or 285°, and the angle between the absorption axis of the linear polarizer and the slow axis of the quarter-wave plate film layer to 165° or 345°, the brightness enhancement film is a right-handed cholesteric liquid crystal. Both left-handed and right-handed cholesteric liquid crystals as brightness enhancement films can improve the light extraction efficiency of blue light, thereby improving both the color cast and the brightness decay rate of the display device at oblique viewing angles. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.

[0035] FIG1 is a schematic structural diagram of a microstructure layer according to an embodiment of the present application;

[0036] FIG2 is a partial view of a microstructure layer according to an embodiment of the present application;

[0037] FIG3 is a schematic structural diagram of a microstructure layer according to another embodiment of the present application;

[0038] FIG4 is a partial view of a microstructure layer according to another embodiment of the present application;

[0039] FIG5 is a partial diagram of a microstructure layer according to another embodiment of the present application;

[0040] FIG6 is a partial diagram of a microstructure layer according to another embodiment of the present application;

[0041] FIG7 is a schematic structural diagram of a microstructure layer according to another embodiment of the present application;

[0042] FIG8 is a schematic structural diagram of a microstructure layer according to another embodiment of the present application;

[0043] FIG9 is a schematic structural diagram of a microstructure layer according to another embodiment of the present application;

[0044] FIG10 is a schematic structural diagram of a display device according to an embodiment of the present application;

[0045] FIG11 is a schematic structural diagram of a display device according to another embodiment of the present application;

[0046] FIG12 is a schematic structural diagram of a display device according to yet another embodiment of the present application;

[0047] FIG13 is a schematic structural diagram of a display device according to another embodiment of the present application;

[0048] FIG14 is a schematic diagram showing the operation of a composite circular polarizer according to an embodiment of the present application;

[0049] FIG15 is a schematic structural diagram of a display device according to another embodiment of the present application.

[0050] Reference numerals:

[0051] 100-microstructure layer, 101-first substrate, 102-first refractive layer, 103-second refractive layer, 1041-embossing, 1042-filling member, 1043-engraved pattern, 110-reworkable adhesive layer, 301-cover plate, 304-black matrix, 305-touch layer, 306-sealing layer, 307-electroluminescent layer, 401-composite circular polarizer, 4011-circular polarizer body, 4012-brightness enhancement film, 4013-second substrate, 4014-linear polarizer, 4015-half-wave plate film layer, 4016-quarter-wave plate film layer, 308-driving circuit layer, 309-base substrate;

[0052] X-first direction, Y-second direction, W-width, H-height. DETAILED DESCRIPTION

[0053] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0054] The "ranges" disclosed herein are defined in terms of lower and upper limits. A given range is defined by selecting a lower limit and an upper limit, and the selected lower and upper limits define the boundaries of the specific range. Ranges defined in this manner are inclusive of the endpoints and can be combined arbitrarily, meaning that any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a particular parameter, it is understood that ranges of 60-110 and 80-120 are also contemplated. Furthermore, if the minimum range values ​​listed are 1 and 2, and if the maximum range values ​​listed are 3, 4, and 5, then the following ranges are all contemplated: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise specified, the numerical range "ab" is an abbreviation for any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed herein, and "0-5" is simply an abbreviation for these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0055] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0056] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0057] The terms used in the following embodiments are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification of this application and the appended claims, the singular expressions "a", "an", "said", "above", "the" and "this" are intended to also include expressions such as "one or more", unless there is a clear contrary indication in the context. It should also be understood that in the following embodiments of the present application, "at least one", "one or more" refer to one, two or more. The term "and / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist; for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship.

[0058] References to "one embodiment," "some embodiments," "an example," or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0059] The terms "above" and "below" used in this specification may refer to relative positions, and are interdependent. The upper and lower positions of the same object may also vary relative to different reference objects. The embodiments of this application illustrate the first substrate being located below in the drawings. Of course, if the display device is reversed, the first substrate may be located above.

[0060] OLEDs are current-type organic light-emitting devices (OLEDs), which emit light through the injection and recombination of charge carriers. The luminescence intensity is proportional to the injected current. Under the influence of an electric field, holes generated at the anode and electrons generated at the cathode migrate, injecting into the hole transport layer and electron transport layer, respectively, and then migrating to the light-emitting layer. When these two molecules meet in the light-emitting layer, they generate energy excitons, which excite luminescent molecules and ultimately produce visible light. OLED display technology features a wide color gamut, high contrast, flexible self-luminescence, and low power consumption, making it one of the mainstream information display technologies used in smart display devices. The development direction of OLED display technology is also aimed at achieving higher luminous efficiency and lower energy consumption. As second-generation luminescent materials, phosphorescent materials can utilize triplet excitons to emit light, improving luminous efficiency and are increasingly being used in OLED display technology. However, phosphorescent materials, especially blue phosphorescent materials, have a large half-value width, which reduces the displayed color purity. Furthermore, in some OLED display devices, the materials used to emit blue, green, and red light using blue phosphorescent materials are fluorescent materials. When a user stands at a relatively oblique angle to view the display screen, a color cast problem occurs because the light generated by the blue phosphorescent material with a wider half-width at half maximum and the light generated by the fluorescent material have different attenuation degrees.

[0061] A common method for improving color shift in OLED display panels is to adjust the aperture ratio of each sub-pixel to control the current density, thereby achieving essentially the same decay curve for the red, green, and blue organic light-emitting materials. However, the varying aperture ratios of each sub-pixel complicate the mask production process, making it difficult to ensure accuracy. Furthermore, the estimated color shift compromises the overall brightness and lifespan of the OLED.

[0062] In view of the above problems, embodiments of the present application provide a microstructure layer and a display device, which can improve the color shift phenomenon at oblique viewing angles.

[0063] Figure 1 is a schematic structural diagram of a microstructure layer according to an embodiment of the present application. As shown in Figure 1 , the microstructure layer 100 includes a first refractive layer 102 and a second refractive layer 103 arranged along a first direction X. The first refractive layer 102 and the second refractive layer 103 have different refractive indices.

[0064] Optionally, the first direction X is the vertical direction of the microstructure layer 100 ; for the convenience of description below, the vertical direction of the microstructure layer 100 is referred to as the first direction X.

[0065] As shown in FIG1 , the microstructure layer 100 further includes a first substrate 101, which serves as a supporting substrate for the microstructure layer 100. The material of the first substrate 101 can be at least one of triacetate cellulose (TAC), polyethylene terephthalate (PET), ultra-thin glass (UTG), colorless polyimide (CPI), polymethyl methacrylate (PMMA), and cycloolefin polymer (COP).

[0066] The first refractive layer 102 and the second refractive layer 103 can be made of PMMA. The refractive index values ​​of the two can be adjusted by adding Zr. The Zr-containing material has a high refractive index, a wide bandgap, good transparency, and low absorption and scattering characteristics in the visible and infrared bands.

[0067] The first refractive layer 102 and the second refractive layer 103 have different refractive indices, and thus can be a high-refractive layer and a low-refractive layer in a relative sense (a high-refractive layer refers to a refractive layer with a high refractive index, and a low-refractive layer refers to a refractive layer with a low refractive index). Specifically, the first refractive layer 102 can be a high-refractive layer, and the second refractive layer 103 can be a low-refractive layer. Alternatively, the first refractive layer 102 can be a low-refractive layer, and the second refractive layer 103 can be a high-refractive layer.

[0068] 1 , an embossing 1041 and a filler 1042 are provided at the interface between the first refractive layer 102 and the second refractive layer 103. In a second direction Y, the embossing 1041 and the filler 1042 are spaced apart. The second direction Y is perpendicular to the first direction X.

[0069] As described above, if the first direction X is the vertical direction of the microstructure layer 100 , then the second direction Y is the horizontal direction of the microstructure layer 100 .

[0070] Optionally, the embossing 1041 and the filling member 1042 are disposed on the first refractive layer 102 and the second refractive layer 103 , that is, the first refractive layer 102 and the second refractive layer 103 serve as substrates.

[0071] Optionally, the spacing arrangement here refers to the spacing arrangement of a single stamp 1041 and a single filler 1042. That is, the specific arrangement in the second direction Y is: stamp 1041, filler 1042, stamp 1041, filler 1042, stamp 1041, filler 1042, ...; or it can be filler 1042, stamp 1041, filler 1042, stamp 1041, filler 1042, stamp 1041, filler 1042, stamp 1041, ..., which is not particularly limited in this application.

[0072] Optionally, an imprint 1041 is provided at the junction of the first refractive layer 102 and the second refractive layer 103 , and nanoimprint technology or other imprint technologies may be used, which is also not limited in the embodiment of the present application.

[0073] The refractive index of the embossing 1041 is the same as that of the first refractive layer 102, or the refractive index of the embossing 1041 is the same as that of the second refractive layer 103. The refractive index of the filler 1042 is the same as that of the first refractive layer 102, or the refractive index of the filler 1041 is the same as that of the second refractive layer 103. The refractive index of the embossing 1041 is different from that of the filler 1042.

[0074] That is, when the refractive index of the imprint 1041 is the same as that of the first refractive layer 102, the refractive index of the filler 1042 may be the same as that of the second refractive layer 103. When the refractive index of the imprint 1041 is the same as that of the second refractive layer 103, the refractive index of the filler 1042 may be the same as that of the first refractive layer 102.

[0075] When the microstructure layer 100 comprises a first refractive layer 102 and a second refractive layer 103 with different refractive indices arranged along a first direction X, and also includes an imprint 1041 and a filler 1042 with different refractive indices spaced apart along a second direction Y, the high and low refractive index layers and the nanoimprint 1041 can redirect the outgoing light path, redistributing the viewing angle light into a new spectrum. In other words, after passing through the microstructure layer 100, the outgoing light can be closer to the normal viewing angle. Furthermore, after optical path adjustment by the microstructure layer 100, the light at each viewing angle is redistributed to include spectral components from low viewing angles and spectral components from high viewing angles, thereby making the spectral profile more similar to the peak at normal viewing angles. Due to the microcavity effect, the light intensity at low viewing angles is significantly stronger than that at high viewing angles, and the newly distributed spectrum will more closely resemble the low-viewing angle peak. Since the spectrum corresponds one-to-one with color coordinates, colors can be quantitatively compared. Changes in peak position and peak width will cause the color coordinates to shift, so the spectral profile adjusted by the microstructure layer 100 will be closer to the peak at normal viewing angles. That is, the change in the half-width of the peak position has hysteresis, which can slow down the viewing angle-dependent color shift caused by the microcavity effect.

[0076] In the above solution, by making the microstructure layer 100 include a first refractive layer 102 and a second refractive layer 103 with different refractive indices, and having an embossing 1041 and a filler 1042 arranged at intervals at the junction of the two, the dependence of the luminous spectrum on the viewing angle change can be reduced, thereby improving the color shift phenomenon under a large viewing angle.

[0077] In some embodiments, the refractive index of the first refractive layer 102 is 1.45-1.9, and the refractive index of the second refractive layer 103 is 1.3-1.6.

[0078] In the above scheme, the refractive index of the first refractive layer is limited to 1.45-1.9, and the refractive index of the second refractive layer is limited to 1.3-1.6, which also limits the refractive index of the stamping and filler. Maintaining the refractive index within this range can redirect the outgoing light path and redistribute the viewing angle light into a new spectrum. The newly formed spectral profile is closer to the peak at normal viewing angles, further improving color shift at wide viewing angles.

[0079] Optionally, the refractive index of the first refractive layer 102 may be 1.45, 1.5, 1.6, 1.8, 1.9 or any value within the above range.

[0080] Optionally, the refractive index of the second refractive layer 103 may be 1.3, 1.35, 1.4, 1.5, 1.5 or any value within the above range.

[0081] It should be understood that the first refractive layer 102 and the second refractive layer 103 should have values ​​within the above respective ranges on the basis of satisfying different refractive indices.

[0082] Figure 2 is a partial view of a microstructure layer according to an embodiment of the present application. As shown in Figure 2 , in some embodiments, the ratio of the dimension of the imprint 1041 in the first direction X to the dimension in the second direction Y is greater than or equal to 1.4.

[0083] As described above, the first direction X is the vertical direction of the microstructure layer 100, which may also be referred to as the height direction of the microstructure layer 100, i.e., the direction of H in FIG2 . The second direction Y is the horizontal direction of the microstructure layer 100, which may also be referred to as the width direction of the microstructure layer 100, i.e., the direction of W in FIG2 .

[0084] In the above solution, the aspect ratio design of the embossing 1041 in the microstructure layer 100 significantly impacts color improvement. A larger aspect ratio results in higher color improvement efficiency and improved color shift at wide viewing angles. By ensuring that the ratio of the dimensions of the embossing 1041 in the first direction X to the second direction Y is no less than 1.4 (i.e., an aspect ratio greater than or equal to 1.4), color shift at oblique viewing angles can be further improved.

[0085] Specifically, the ratio of the height-to-width ratio of the imprint 1041 in the first direction X to the second direction Y can be 1.4, 1.5, 1.8, 2.1, 2.5, or any value within the above ranges.

[0086] Figure 3 is a schematic diagram of the structure of a microstructure layer according to another embodiment of the present application. As shown in Figure 3, in some embodiments, the embossing 1041 has an intaglio pattern 1043, and the ratio of the area of ​​the intaglio pattern 1043 to the area of ​​the embossing 1041 is greater than or equal to 0.35.

[0087] In the embodiment of this application, the pattern density on the imprint 1041 significantly affects the color improvement rate. Generally speaking, the greater the pattern density on the imprint 1041, the greater the proportion of components participating in the light path refraction, the greater the degree of adjustment to the light path, and thus the relatively better improvement in color difference. Therefore, by ensuring that the intaglio pattern 1043 accounts for no less than 35% of the area on the imprint 1041, color shift at oblique viewing angles can be further improved.

[0088] The present application does not particularly limit the specific shape of the intaglio pattern 1043. For example, the intaglio pattern 1043 may be rectangular or trapezoidal.

[0089] In some embodiments, the topography of the imprint 1041 includes at least one of a rectangle, a trapezoid, a triangle, and an ellipse.

[0090] Figures 4-6 are partial views of the microstructure layer according to some embodiments of the present application. As shown in Figures 4-6, the embossing 1041 on the microstructure layer 100 can have various morphologies, such as the rectangle in Figure 1, the ellipse in Figure 4, the inverted trapezoid in Figure 5, and the triangle in Figure 6.

[0091] It should be understood that the embossing 1041 and the filling member 1042 may have the same shape. For example, as shown in FIG5 , the embossing 1041 and the filling member 1042 are both trapezoidal in shape. Alternatively, the embossing 1041 and the filling member 1042 may have different shapes. For example, as shown in FIG6 , the embossing 1041 is trapezoidal in shape and the filling member 1042 is triangular in shape.

[0092] It should be understood that the morphology of the imprint 1041 represented here refers to the cross-sectional morphology of the imprint 1041 .

[0093] FIG7 is a schematic diagram of the structure of a microstructure layer according to another embodiment of the present application. As shown in FIG1 and FIG7, in some embodiments, in a first direction X, the first refractive layer 102 is located above the second refractive layer 103. Alternatively, in the first direction X, the second refractive layer 103 is located above the first refractive layer 102.

[0094] Figures 8 and 9 are schematic diagrams of the microstructure layer according to some embodiments of the present application. As shown in Figures 8 and 9, the microstructure layer 100 includes a plurality of first refractive layers 102 and a plurality of second refractive layers 103. In a first direction X, the plurality of first refractive layers 102 and the plurality of second refractive layers 103 are arranged at intervals.

[0095] When the microstructure layer 100 includes two second refractive layers 103 and one first refractive layer 102, the specific configuration of the microstructure layer 100 can be as shown in FIG8 . That is, in the first direction X, the microstructure layer 100 includes, from top to bottom, the second refractive layer 103, the first refractive layer 102, and the second refractive layer 103. Alternatively, the specific configuration of the microstructure layer 100 from top to bottom can also be: the second refractive layer 103, the second refractive layer 103, and the first refractive layer 102. Alternatively, the specific configuration of the microstructure layer 100 from top to bottom can also be: the first refractive layer 102, the second refractive layer 103, and the second refractive layer 103.

[0096] When the microstructure layer 100 includes two first refractive layers 102 and two second refractive layers 103, the specific configuration of the microstructure layer 100 can be as shown in FIG9 . That is, in the first direction X, the microstructure layer 100 includes, from top to bottom, the first refractive layer 102, the second refractive layer 103, the first refractive layer 102, and the second refractive layer 103. Alternatively, the specific configuration of the microstructure layer 100 from top to bottom can also be: the first refractive layer 102, the first refractive layer 102, the second refractive layer 103, and the second refractive layer 103. Alternatively, the specific configuration of the microstructure layer 100 from top to bottom can also be: the second refractive layer 103, the second refractive layer 103, the first refractive layer 102, and the first refractive layer 102.

[0097] In other words, the present application does not impose any particular limitation on the number of first refractive layers 102 and second refractive layers 103 included in the microstructure layer 100. Furthermore, as shown in Figures 8 and 9 , the first refractive layer 102 or the second refractive layer 103 located in the middle may have an embossing 1041 at both sides of the boundary, or may have an embossing 1041 at only one side of the boundary, and this is also not limited in the present application.

[0098] In the above solution, the first refractive layer 102 and the second refractive layer 103 in the microstructure layer 100 may have multiple layers, and the first refractive layer 102 and the second refractive layer 103 may be arranged in different arrangements, so that the microstructure layer 100 can be installed according to assembly requirements.

[0099] Figure 10 is a schematic diagram of the structure of a display device according to the present application. As shown in Figure 10 , the display device 300 includes a microstructure layer 100, which is the microstructure layer described in any of the above embodiments. The display device 300 includes a base substrate 309, a drive circuit layer 308 located on one side of the base substrate 309, an electroluminescent layer 307 located on the side of the drive circuit layer 308 facing away from the base substrate 309, and the microstructure layer 100 located on the side of the electroluminescent layer 307 facing away from the base substrate 309.

[0100] In some embodiments, the display device 300 further includes a black matrix 304 . The black matrix 304 is disposed on a side of the microstructure layer 100 close to the base substrate 309 , that is, the black matrix 304 is disposed below the microstructure layer 100 .

[0101] Optionally, the different film layers in this application are connected by an adhesive layer. The adhesive layer can be one of a shadowless adhesive (UV adhesive), a pressure-sensitive adhesive, a heat-curing water-based adhesive, or other adhesives commonly used in the OLED assembly process. This application does not limit this. In addition, the adhesive layer may or may not appear in the drawings. This does not affect the structural arrangement of this application and does not affect the scope of this application.

[0102] Optionally, in the embodiment of the present application, the display device 300 may be a display device such as an OLED display, as well as any product or component with a display function, such as a television, a digital camera, a mobile phone, a tablet computer, etc. that includes these display devices.

[0103] In the above solution, the microstructure layer 100 is disposed above the black matrix 304 , which can reduce the dependence of the light emitting spectrum on the viewing angle change, thereby improving the color shift phenomenon.

[0104] In some embodiments, the display device 300 further includes a cover plate 301 and a composite circular polarizer 401. The cover plate 301 is located on the side of the composite circular polarizer 401 away from the base substrate 309, that is, the cover plate 301 is located above the composite circular polarizer 401. The microstructure layer 100 is located on the side of the cover plate 301 away from the base substrate 309, that is, the microstructure layer 100 is located above the cover plate 301. Alternatively, the microstructure layer 100 is located between the cover plate 301 and the composite circular polarizer 401. Alternatively, the microstructure layer 100 is located on the side of the composite circular polarizer 401 closer to the base substrate 309, that is, the microstructure layer 100 is located below the composite circular polarizer 401.

[0105] The cover plate 301 is disposed on top of the composite circular polarizer 401 to protect the composite circular polarizer 401. The cover plate 301 can be made of at least one of CPI, PET, or UTG. The cover plate 301 can be multi-layered, i.e., two or more layers. When the cover plate 301 has two or more layers, the multi-layered cover plate 301 can be made of the same material or a combination of different materials.

[0106] As shown in FIG10 , when the display device 300 further includes a cover plate 301 and a composite circular polarizer 401, the microstructure layer 100 is located below the composite circular polarizer 401. The display device 300 may include, from top to bottom, the following: a cover plate 301, a composite circular polarizer 401, a microstructure layer 100, a black matrix 304, a touch layer 305, an encapsulation layer 306, an electroluminescent layer 307, a driving circuit layer 308, and a base substrate 309.

[0107] The encapsulation layer 306 is made of an insulating material, for example, at least one of silicon nitride, silicon oxide, silicon oxynitride, and aluminum oxide.

[0108] Figure 11 is a schematic structural diagram of another display device of the present application. As shown in Figure 11, the microstructure layer 100 is located above the cover plate 301. It should be noted here that when the microstructure layer 100 is located at the top of the display device 300, the microstructure layer 100 can be used as a protective film for the display screen. In this case, in order to ensure the repair effect, the microstructure layer 100 needs to be used with a repairable adhesive material, that is, a repairable adhesive layer 110 is provided between the microstructure layer 100 and the cover plate 301. Therefore, the display device 300 is sequentially arranged from top to bottom including: a microstructure layer 100, a repairable adhesive layer 110, a cover plate 301, a composite circular polarizer 401, a black matrix 304, a touch layer 305, a sealing layer 306, an electroluminescent layer 307, a driving circuit layer 308 and a base substrate 309.

[0109] Figure 12 is a schematic diagram of the structure of a display device according to another embodiment of the present application. As shown in Figure 12, the microstructure layer 100 is located between the cover plate 301 and the composite circular polarizer 401. The display device 300 includes, from top to bottom: the cover plate 301, the microstructure layer 100, the composite circular polarizer 401, the black matrix 304, the touch layer 305, the sealing layer 306, the electroluminescent layer 307, the drive circuit layer 308, and the base substrate 309.

[0110] Figure 13 is a schematic structural diagram of a display device according to another embodiment of the present application. As shown in Figures 12 and 13, in some embodiments, when the microstructure layer 100 is located between the cover plate 301 and the composite circular polarizer 401, the microstructure layer 100 is located in a first region corresponding to the opening region 3041 of the black matrix 304, or in a second region 3042 corresponding to the non-opening region of the black matrix 304.

[0111] In the above solution, color shift at oblique viewing angles can be improved by providing the microstructure layer 100 in the display device 300. There are multiple options for the position of the microstructure layer 100, so the position of the microstructure layer 100 can be selected according to the actual production process.

[0112] In some embodiments, the composite circular polarizer 401 includes a circular polarizer body and a brightness enhancement film, wherein the brightness enhancement film is disposed below the circular polarizer body. The brightness enhancement film is made of cholesteric liquid crystal, and the center wavelength of the reflection spectrum of the brightness enhancement film is 450 nm (nanometers) to 480 nm.

[0113] FIG14 is a schematic diagram illustrating the operation of a composite circular polarizer according to one embodiment of the present application. As shown in FIG14 , the central wavelength of the reflected light spectrum of the brightness enhancement film is 450 nm to 480 nm, and the material of the brightness enhancement film includes cholesteric liquid crystals (CLC), i.e., the brightness enhancement film is a blue light CLC brightness enhancement film. The principle of blue light anti-reflection is that when the panel emits blue light, it encounters the brightness enhancement film made of cholesteric liquid crystals, which decomposes the panel's emitted light into approximately 50% right-handed light and approximately 50% left-handed light. The 50% right-handed light passes through the brightness enhancement film and exits the display module normally, while the 50% left-handed light is reflected back to the panel, where it is reflected by the panel and converted into right-handed light, which then passes through the brightness enhancement film and exits the display module. Under the same current drive, the blue light brightness enhancement efficiency can be maintained at 20% to 40%, thereby improving both the color cast and the brightness decay rate of the display device 300 at oblique viewing angles.

[0114] Optionally, the central wavelength of the reflected light spectrum of the brightness enhancing film may be 450 nm, 455 nm, 460 nm, 470 nm, 480 nm or any value within the above range.

[0115] In some embodiments, the half-peak width of the reflected light spectrum of the brightness enhancing film is 5 nm to 80 nm.

[0116] In the embodiment of the present application, by making the half-peak width of the reflected light spectrum of the brightness enhancement film be 5nm-80nm, the brightness of the light output can be further increased, the reflectivity can be reduced, and the dark state can be reduced.

[0117] Optionally, the half-peak width of the reflected light spectrum of the brightness enhancing film can be 5 nm, 15 nm, 50 nm, 60 nm, 80 nm or any value within the above range.

[0118] In some embodiments, the brightness enhancement film has a thickness less than or equal to 5 μm.

[0119] In the embodiment of the present application, if the thickness of the brightness enhancement film is too high, it is not conducive to spectral emission and bending of the display device. Therefore, the thickness of the brightness enhancement film is kept less than or equal to 5 μm.

[0120] Specifically, the thickness of the brightness enhancement film can be 5um, 4um, 3.5um, 3um, 2um or any value within the above range.

[0121] FIG15 is a schematic structural diagram of a display device according to another embodiment. As shown in FIG15 , in one possible embodiment, a circular polarizer body 4011 includes, arranged in order from top to bottom, a second substrate 4013, a linear polarizer 4014, a half-wave plate layer 4015, and a quarter-wave plate layer 4016. The angle between the absorption axis of the linear polarizer 4014 and the slow axis of the half-wave plate layer 4015 is 15°, and the angle between the absorption axis of the linear polarizer 4014 and the slow axis of the quarter-wave plate layer 4016 is 75°. Alternatively, the angle between the absorption axis of the linear polarizer 4014 and the slow axis of the half-wave plate layer 4015 is 105° or 285°, and the angle between the absorption axis of the linear polarizer 4014 and the slow axis of the quarter-wave plate layer 4016 is 165° or 345°.

[0122] The linear polarizer 4014 is an iodine-based stretched linear polarizing functional film that converts natural light into linearly polarized light. The linear polarizer 4014 has an absorption axis that is generally perpendicular to the surface of the linear polarizer 4014.

[0123] Half-wave plate layer 4015 has a fast axis and a slow axis in a plane parallel to the panel. Light waves passing through half-wave plate layer 4015 produce a phase difference of half a wavelength. Quarter-wave plate layer 4016 has a fast axis and a slow axis in a plane parallel to the panel. Light waves passing through quarter-wave plate layer 4016 produce a phase difference of a quarter wavelength. The slow axis is the direction of the light vector with the slowest propagation speed in the wave plate, while the fast axis is the direction of the light vector with the fastest propagation speed in the wave plate. The fast and slow axes are perpendicular to each other.

[0124] In the above scheme, by setting the angle between the absorption axis of the linear polarizer 4014 and the slow axis of the half-wave plate layer 4015 to 15°, and the angle between the absorption axis of the linear polarizer 4014 and the slow axis of the quarter-wave plate layer 4016 to 75°, the brightness enhancement film 4012 is a left-handed cholesteric liquid crystal. By setting the angle between the absorption axis of the linear polarizer 4014 and the slow axis of the half-wave plate layer 4015 to 105° or 285°, and the angle between the absorption axis of the linear polarizer 4014 and the slow axis of the quarter-wave plate layer 4016 to 165° or 345°, the brightness enhancement film 4012 is a right-handed cholesteric liquid crystal. Both left-handed cholesteric liquid crystal and right-handed cholesteric liquid crystal as the brightness enhancement film 4012 can improve the light extraction efficiency of blue light, thereby improving the color shift of the display device 300 at oblique viewing angles and the brightness decay rate at oblique viewing angles.

[0125] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any embodiments having substantially the same structure and effect as the technical concept within the scope of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the present application, any other methods constructed by applying various modifications that can be imagined by those skilled in the art to the embodiments and combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A microstructure layer, characterized in that: include: A first refractive layer and a second refractive layer arranged along a first direction, wherein the first refractive layer and the second refractive layer have different refractive indices; A stamping and a filling piece are arranged at the junction of the first refractive layer and the second refractive layer, and the stamping and the filling piece are arranged at intervals in a second direction, and the second direction is perpendicular to the first direction; The refractive index of the embossing is the same as that of the first refractive layer, or the refractive index of the embossing is the same as that of the second refractive layer, the refractive index of the filler is the same as that of the first refractive layer, or the refractive index of the filler is the same as that of the second refractive layer, and the refractive index of the embossing is different from that of the filler.

2. The microstructure layer according to claim 1, characterized in that: The refractive index of the first refractive layer is 1.45-1.9, and the refractive index of the second refractive layer is 1.3-1.

6.

3. The microstructure layer according to claim 1 or 2, characterized in that: A ratio of a size of the embossing in the first direction to a size of the embossing in the second direction is greater than or equal to 1.

4.

4. The microstructure layer according to claim 1 or 2, characterized in that: The stamp has an intaglio pattern, and the ratio of the area of ​​the intaglio pattern to the area of ​​the stamp is greater than or equal to 0.

35.

5. The microstructure layer according to claim 1 or 2, characterized in that: The embossed shape includes at least one of a rectangle, a trapezoid, a triangle and an ellipse.

6. The microstructure layer according to claim 1 or 2, characterized in that: The microstructure layer includes a plurality of the first refractive layers and a plurality of the second refractive layers; In the first direction, a plurality of the first refraction layers and a plurality of the second refraction layers are arranged at intervals.

7. The microstructure layer according to claim 1 or 2, characterized in that: The microstructure layer further comprises a first substrate; In the first direction, the first substrate is arranged on one side of the first refractive layer and the second refractive layer, and the material of the first substrate includes at least one of triacetyl cellulose, polyethylene terephthalate, ultra-thin flexible glass, transparent polyimide, polymethyl methacrylate or cycloolefin polymer.

8. A display device, characterized in that: The display device comprises the microstructure layer as claimed in any one of claims 1 to 7; The display device includes a base substrate, a driving circuit layer located on one side of the base substrate, an electroluminescent layer located on a side of the driving circuit layer away from the base substrate, and the microstructure layer located on a side of the electroluminescent layer away from the base substrate.

9. The display device according to claim 8, characterized in that: The display device further comprises a black matrix, and the black matrix is ​​arranged on a side of the microstructure layer close to the base substrate.

10. The display device according to claim 9, characterized in that: The display device further comprises a cover plate and a composite circular polarizer, wherein the cover plate is located on a side of the composite circular polarizer away from the base substrate; in, The microstructure is located on a side of the cover plate away from the substrate; or, The microstructure layer is located between the cover plate and the composite circular polarizer; or, The microstructure layer is located on a side of the composite circular polarizer close to the base substrate.

11. The display device according to claim 10, characterized in that: When the microstructure layer is located between the cover plate and the composite circular polarizer, the microstructure layer is located in a first area corresponding to an opening area of ​​the black matrix, or the microstructure layer is located in a second area corresponding to a non-opening area of ​​the black matrix.

12. The display device according to claim 10, characterized in that: The composite circular polarizer comprises a circular polarizer body and a brightness enhancement film, wherein the brightness enhancement film is located on a side of the circular polarizer body close to the base substrate; The material of the brightness enhancement film includes cholesteric liquid crystal, and the central wavelength of the reflected light spectrum of the brightness enhancement film is 450nm-480nm.

13. The display device according to claim 12, characterized in that: The half-peak width of the reflected light spectrum of the brightness enhancement film is 5nm-80nm.

14. The display device according to claim 12, characterized in that: The thickness of the brightness enhancement film is less than or equal to 5 um.

15. The display device according to any one of claims 12 to 14, characterized in that: The circular polarizer body comprises a first substrate, a linear polarizer, a half-wave plate film layer and a quarter-wave plate film layer which are sequentially arranged in a direction close to the substrate; in, The angle between the absorption axis direction of the linear polarizer and the slow axis direction of the half-wave plate film layer is 15°, and the angle between the absorption axis direction of the linear polarizer and the slow axis direction of the quarter-wave plate film layer is 75°; or, The angle between the absorption axis of the linear polarizer and the slow axis of the half wave plate film layer is 105° or 285°, and the angle between the absorption axis of the linear polarizer and the slow axis of the quarter wave plate film layer is 165° or 345°.

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