Polarizing filter and its manufacturing method, display panel

Abstract

The present application provides a polarizing filter, a manufacturing method thereof, and a display panel. The polarizing filter includes a polarizing film and a protective layer disposed on one side of the polarizing film. A textured structure is disposed on the side of the protective layer away from the polarizing film, and the textured structure includes a plurality of sub-textured surfaces with different shapes and / or sizes, thereby resolving the technical problem of rainbow unevenness in conventional display devices.

Description

[Technical Field]

[0001] The present application relates to the display technology field, and in particular to a polarizing filter and a manufacturing method thereof, and a display panel. [Background technology]

[0002] With the rapid development of LCD technology, LCDs have been widely used in the screens of small mobile phones and now large computers and televisions, becoming the mainstream product in the display technology field, and the market is placing higher and higher requirements on the image quality and environmental compatibility of display devices.

[0003] An LCD device primarily consists of a layer of liquid crystal sandwiched between two glass substrates, and from bottom to top: a backlight, a light guide plate, a lower polarizing filter, a lower glass substrate, a thin-film transistor array, a liquid crystal layer, a color filter, an upper glass substrate, and an upper polarizing filter. Light emitted from the backlight is diffused by the light guide plate and then passes through a lower polarizing filter with an absorption axis oriented at 90° (perpendicular to the paper), where the 90° component of natural light is absorbed, resulting in linear polarization parallel to the 0° direction (parallel to the paper). When there is no change in electric field, the liquid crystal molecules do not polarize, and the outgoing linearly polarized light, while remaining unchanged, is absorbed by the upper polarizing filter with an absorption axis oriented at 0°. This prevents light from passing through, resulting in a dark display. When a current passes through the transistor and a change in electric field occurs, the liquid crystal molecules polarize, causing the polarization direction of the horizontally linearly polarized light to become vertical. This causes the light to pass through the upper polarizing filter without being absorbed, resulting in a bright display. In addition, the upper glass is bonded with a color filter, and based on the principles of chromaticity, each pixel is composed of three sub-pixels (RGB), and these red, blue, and green emitting sub-pixels are mixed and transmitted to the user's eyes, creating a colorful display screen.

[0004] In the operating principle of display devices, polarizing filters play a vital role as optical switches, and are basically composed of a substrate protection layer, a polarizing layer, a liquid crystal compensation layer, a pressure-sensitive adhesive (PSA), and a release film. Over time, the substrate protection layer is used to create a polarizing filter with a polyethylene terephthalate (PET) substrate, and the crystalline properties of the PET material can create a birefringence effect, which can easily cause rainbow effects in display devices. Summary of the Invention [Problem to be solved by the invention]

[0005] The present application provides a polarizing filter and a manufacturing method thereof, and a display panel, thereby alleviating the technical problem of the rainbow phenomenon that exists in conventional display devices. [Means for solving the problem]

[0006] In order to solve the above problems, the present application provides the following technical solutions.

[0007] An embodiment of the present application provides a polarizing filter, the polarizing filter comprising: A polarizing film; a protective layer disposed on one side of the polarizing film; Here, the protective layer has a concave-convex structure on the side farther from the polarizing film, and the concave-convex structure includes a plurality of sub-convex surfaces having different shapes and / or sizes.

[0008] In the polarizing filter according to the embodiment of the present application, the polarizing filter further includes a light-control film disposed on the side of the protective layer farther from the polarizing film, and one side of the light-control film has the uneven structure.

[0009] In a polarizing filter according to an embodiment of the present application, the side of the photochromic film far from the protective layer has the uneven structure, and the photochromic film includes a base layer and first diffusing particles dispersed in the base layer, and at least some of the first diffusing particles protrude from the surface of the photochromic film far from the protective layer to form the uneven structure.

[0010] In a polarizing filter according to an embodiment of the present application, the side of the photochromic film closer to the protective layer has the uneven structure. The photochromic film includes a base layer and first diffusing particles dispersed in the base layer, and at least some of the first diffusing particles protrude from the surface of the photochromic film closer to the protective layer to form the uneven structure.

[0011] In the polarizing filter according to the embodiment of the present application, the photochromic film further includes second diffusing particles dispersed within the substrate layer, the second diffusing particles and the first diffusing particles protrude from the surface of the same side of the photochromic film, and some of the first diffusing particles are located on the side of the second diffusing particles farther from the uneven structure.

[0012] In the polarizing filter according to the embodiment of the present application, the particle size of the first diffusing particles is larger than the particle size of the second diffusing particles.

[0013] In the polarizing filter according to the embodiment of the present application, the substrate layer includes an ultraviolet curable resin substrate, the first diffusing particles include polymethyl methacrylate particles, and the second diffusing particles include at least one of silicon dioxide particles, titanium dioxide particles, and zinc dioxide particles.

[0014] In the polarizing filter according to the embodiment of the present application, the haze range of the polarizing filter is 20% to 70%.

[0015] In the polarizing filter according to the embodiment of the present application, the angle formed between the normal to the sub-convexoconcave surface and a plane parallel to the plane on which the protective layer is located ranges from 0° to 180°.

[0016] An embodiment of the present application further provides a method for manufacturing a polarizing filter, the method comprising: applying a protective layer to one side of the polarizing film; forming a concave-convex structure on the side of the protective layer away from the polarizing film, the concave-convex structure including a plurality of sub-convex surfaces with different shapes and / or sizes;

[0017] In the manufacturing method of a polarizing filter according to the embodiment of the present application, the step of forming a concavo-convex structure on the side of the protective layer farther from the polarizing film includes: mixing an ultraviolet curable resin, an ultraviolet curable monomer, and first diffusing particles in a solvent to form a light control liquid; coating the photochromic liquid on the side of the protective layer farther from the polarizing film; The method includes curing the photochromic liquid to form the photochromic film, and forming the uneven structure on one side of the photochromic film.

[0018] In the method for manufacturing a polarizing filter according to the embodiment of the present application, the light control liquid further contains second diffusing particles, the particle size of which is smaller than that of the first diffusing particles. The second diffusing particles contain inorganic silicon dioxide particles with a particle size of 30 nm to 70 nm, and the first diffusing particles contain polymethyl methacrylate particles with a particle size of 2 μm to 3 μm.

[0019] In the manufacturing method of the polarizing filter according to the embodiment of the present application, the mass fraction of the first diffusing particles and the second diffusing particles in the dimming liquid ranges from 2.5% to 20%, and the ratio of the first diffusing particles to the second diffusing particles is 7:3.

[0020] An embodiment of the present application further provides a display panel, which includes a polarizing filter according to any one of the above embodiments, or a polarizing filter manufactured by the polarizing filter manufacturing method according to any one of the above embodiments. [Effects of the Invention]

[0021] The present application provides a polarizing filter, a manufacturing method thereof, and a display panel, in which the polarizing filter includes a polarizing film and a protective layer, the protective layer being disposed on one side of the polarizing film, and the protective layer being provided with a textured structure on the side remote from the polarizing film, the textured structure including a plurality of sub-textured surfaces of different shapes and / or sizes. By disposing the textured structure on the protective layer on the side remote from the polarizing film, the present application provides a method for scattering light so that when light passing through the textured structure toward the polarizing filter passes through the textured structure, the light is uniformly scattered based on the principle of diffuse reflection. When the uniformly scattered light passes through the protective layer again, the energy of the light intensity of each wavelength is uniformly dispersed, thereby avoiding the occurrence of rainbow unevenness and resolving the technical problem of rainbow unevenness in conventional display devices. [Brief explanation of the drawings]

[0022] In order to more clearly explain the technical solutions in the embodiments or prior art, the drawings necessary in the description of the technical solutions in the embodiments or prior art will be briefly described below. However, the drawings in the following description are merely some examples of the invention, and those skilled in the art can obtain other drawings from these drawings without any creative efforts.

[0023] [Figure 1] 1 is a schematic diagram showing a cross-sectional structure of a polarizing filter according to an embodiment of the present application. [Figure 2] 1 is a schematic diagram showing a detailed structure of a light-control film according to an embodiment of the present application. [Figure 3] 1 is a schematic diagram illustrating a cross-sectional structure of a display panel according to an embodiment of the present application. [Figure 4] FIG. 10 is a schematic diagram showing another cross-sectional structure of the display panel according to the embodiment of the present application. [Figure 5] FIG. 10 is a schematic diagram showing another cross-sectional structure of the display panel according to the embodiment of the present application. [Figure 6] 10A and 10B are schematic diagrams illustrating propagation of light when the display panel according to the embodiment of the present application does not include a light control film. [Figure 7] 1 is a schematic diagram showing propagation of light when a display panel according to an embodiment of the present application includes a light control film. [Figure 8]FIG. 2 is a flow diagram illustrating a method for manufacturing a polarizing filter according to an embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0024] The following description of each embodiment refers to the accompanying drawings to illustrate specific embodiments in which the present application may be practiced. Directional terms used in the present application, such as "upper," "lower," "front," "rear," "left," "right," "inner," "outer," "side," etc., merely refer to directions in the accompanying drawings. Therefore, it should be understood that the directional terms used are used to explain and understand the present application and are not intended to limit the present application. In the drawings, parts with similar configurations are indicated by the same reference numerals. In the drawings, the thickness of some layers and regions is exaggerated for clarity and ease of explanation. That is, the dimensions and thickness of each component in the drawings are arbitrary, but the present application is not limited thereto.

[0025] In response to the technical issue of rainbow unevenness in conventional display devices, the inventors of the present application discovered during their research that polyethylene terephthalate (PET) in polarizing filters becomes anisotropic after being stretched and formed into a film due to the crystalline properties of the material, and a birefringence effect occurs when light passes through PET. When white light passes through PET material, the material has the characteristic of selective light transmission, and the transmittance of light of different wavelengths is different, where the light transmittance in the 500nm wavelength band is low and the transmittance in the 450nm and 600nm wavelength bands is high, which is why the rainbow unevenness phenomenon occurs.

[0026] Therefore, in order to solve the above problems, the present application provides a polarizing filter and a method for manufacturing the same.

[0027] 1 to 3 are schematic diagrams showing the cross-sectional structure of a polarizing filter according to an embodiment of the present application, FIG. 2 is a schematic diagram showing the detailed structure of a light control film according to an embodiment of the present application, and FIG. 3 is a schematic diagram showing the cross-sectional structure of a display panel according to an embodiment of the present application. Referring to FIG. 1, the polarizing filter 20 includes a protective layer 21 and a polarizing film 22. The protective layer 21 is disposed on one side of the polarizing film 22. A concavo-convex structure 301 is provided on the side of the protective layer 21 away from the polarizing film 22, and the concavo-convex structure 301 includes a plurality of sub-concave surfaces 310 having different shapes and / or sizes.

[0028] In this embodiment, by arranging a concave-convex structure 301 on the side of the protective layer 21 farther from the polarizing film 22, when light heading toward the polarizing filter 20 passes through the concave-convex structure 301, the light is uniformly scattered based on the principle of diffuse reflection. When the uniformly scattered light passes through the protective layer 21 of the polarizing filter 20 again, the energy of the light intensity of each wavelength is uniformly dispersed, thereby avoiding the occurrence of rainbow unevenness and solving the technical problem of rainbow unevenness existing in conventional display devices.

[0029] 1 , preferably, the polarizing filter 20 further includes a light control film 30 disposed on the side of the protective layer 21 farther from the polarizing film 22, and one side of the light control film 30 has the uneven surface structure 301. That is, the uneven surface structure 301 located on the side of the protective layer 21 farther from the polarizing film 22 is formed by the light control film 30. The light control film 30 may be directly formed on the protective layer 21 of the polarizing filter 20, or may be directly attached to the protective layer 21 of the polarizing filter 20.

[0030] The photochromic film 30 has a concave-convex structure 301, which is located on a side of the photochromic film 30 farther from the protective layer 21. The concave-convex structure 301 includes a plurality of irregular sub-concave surfaces 310, which have different shapes and / or sizes. Here, the "irregularity" of the irregular sub-concave surfaces 310 refers to the fact that the shape and arrangement of each sub-concave surface 310 do not have a certain regularity, for example, the shape and / or size of each sub-concave surface 310 are different. Here, the "size" may refer to the height of each sub-concave surface 310 from the protective layer 21, the area of ​​each sub-concave surface 310, etc.

[0031] The configuration of the light control film 30 will be specifically described below.

[0032] Referring to Figures 1 and 2 together, the photochromic film 30 includes a substrate layer 31 and first diffusing particles 32 dispersed in the substrate layer 31, and at least some of the first diffusing particles 32 protrude from the surface of the photochromic film 30 farther from the protective layer 21 to form the uneven structure 301.

[0033] Furthermore, the photochromic film 30 includes second diffusing particles 33 dispersed in the base layer 31, and the second diffusing particles 33 and the first diffusing particles 32 protrude from the surface of the same side of the photochromic film 30, with some of the first diffusing particles 32 located on the side of the second diffusing particles 33 farther from the uneven structure 301. The ratio of the first diffusing particles 32 to the second diffusing particles 33 is 7:3.

[0034] The particle size of the second diffusing particles 33 is smaller than that of the first diffusing particles 32. For example, the particle size of the first diffusing particles 32 may be in the range of 2 μm to 3 μm, such as 2 μm, 2.1 μm, 2.2 μm, 2.6 μm, 2.8 μm, or 3 μm. The particle size of the second diffusing particles 33 may be in the range of 30 nm to 70 nm, such as 30 nm, 40 nm, 50 nm, 60 nm, or 70 nm. Preferably, the first diffusing particles 32 include polymethylmethacrylate (PMMA) particles or the like, and the second diffusing particles 33 include at least one of silicon dioxide particles, titanium dioxide particles, or zinc dioxide particles. The base layer 31 includes an ultraviolet curable resin base material, such as an epoxy acrylate oligomer or a urethane acrylate oligomer having a molecular weight of several hundred to several tens of thousands.

[0035] The first diffusing particles 32 and the substrate layer 31 are made of different materials and are not fused with each other in the same system, so the first diffusing particles 32 are randomly distributed within the substrate layer 31. When some of the first diffusing particles 32 are distributed on the side of the substrate layer 31 farther from the protective layer 21, they protrude from the surface of the photochromic film 30 farther from the protective layer 21 and form the uneven structure 301. On the other hand, when some of the first diffusing particles 32 are distributed on the side of the substrate layer 31 closer to the protective layer 21, they are completely enclosed by the substrate layer 31. Because the positions at which the first diffusing particles 32 are distributed and the number of the first diffusing particles 32 distributed at different positions are random and not uniform, the uneven structure 301 formed on the photochromic film 30 is also irregular.

[0036] Similarly, the second diffusing particles 33 and the substrate layer 31 are made of different materials and are not fused with each other in the same system, so the second diffusing particles 33 are also randomly distributed within the substrate layer 31. When some of the second diffusing particles 33 are distributed on the side of the substrate layer 31 far from the protective layer 21, they protrude from the surface of the photochromic film 30 far from the protective layer 21, like the first diffusing particles 32, and form the unevenness structure 301. In addition, because the positions at which the second diffusing particles 33 are distributed and the number of the second diffusing particles 33 distributed at different positions are random and not constant, the unevenness structure 301 formed on the photochromic film 30 is also irregular.

[0037] The density of the first diffusion particles 32 is greater than the density of the second diffusion particles 33, so that the first diffusion particles 32 are more likely to accumulate than the second diffusion particles 33; that is, the number of the first diffusion particles 32 that are farther from the uneven structure 301 is greater than the number of the second diffusion particles 33 that are farther from the uneven structure 301, so that some of the first diffusion particles 32 are located on the side of the second diffusion particles 33 that is farther from the uneven structure 301.

[0038] In addition, the particle diameter of the first diffusing particles 32 is larger than that of the second diffusing particles 33, so that the second diffusing particles 33 gather on the surface of the substrate layer 31 to form large clusters, which facilitates the formation of the uneven structure 301. In addition, because the particle diameter of the second diffusing particles 33 is small, a plurality of the second diffusing particles 33 gather together to form the uneven structure 301 with a larger number of shapes. As a result, the second diffusing particles 33 can be combined with the first diffusing particles 32 to more effectively form the irregular uneven structure 301. In addition, when the polarizing film 20 is applied to a display panel, the combination of the first diffusing particles 32 and the second diffusing particles 33 makes the subjective effect of a dark screen of the display panel appear bluish, thereby improving the subjective visual sensation.

[0039] The uneven structure 301 is composed of a plurality of uneven sub-surfaces 310, and the plurality of uneven sub-surfaces 310 combine to form the uneven structure 301. The irregular uneven structure 301 is composed of a plurality of irregular uneven sub-surfaces 310. The irregular state of the uneven sub-surface 310 can be measured by the angle between a normal to the uneven sub-surface 310 and a plane parallel to the plane on which the protective layer 21 is located. For example, the angle between the normal to the uneven sub-surface 310 and the plane parallel to the plane on which the protective layer 21 is located ranges from 0° to 180°. Specifically, a straight line in a plane parallel to the plane on which the protective layer 21 is located is defined as a reference line, and this reference line is defined as a horizontal line. As shown in Figure 2, H represents the horizontal line, ON represents the normal to the sub-convexo-concave surface 310, TL represents the tangent line to the sub-convexo-concave surface 310, the normal line ON is perpendicular to the tangent line TL, and a is the angle between the normal line ON to the sub-convexo-concave surface 310 and the horizontal line H. The angle a between the normal ON of the sub-convex surface 310 and the horizontal line H has a distribution from 0° to 180°. For example, the angle a can include integer angles such as 0°, 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80°, 90°, 100°, 110°, 120°, 130°, 140°, 150°, 160°, 170°, and 180°. Of course, the angle a can also include non-integer angles such as 33.6°, 62.8°, and 121.9°.

[0040] Furthermore, the haze range of the polarizing filter 20 is 20% to 70%, and may be, for example, 20%, 30%, 40%, 50%, 60%, 70%, etc. The haze range of the polarizing filter 20 is mainly determined by the state of the uneven structure 301 of the photochromic film 30. Therefore, the haze range of the polarizing filter 20 can be used as another index for measuring the state of irregularity of the uneven structure 301 of the photochromic film 30. Here, the haze range of the polarizing filter 20 refers to the percentage of the intensity of the total transmitted light that is emitted from the polarizing filter 20 at an angle of 2.5° or more.

[0041] In this embodiment, only an example in which the photochromic film includes the first diffusing particles 32 and the second diffusing particles 33 dispersed in the base layer 31 is described, but the present application is not limited thereto. In the photochromic film 30 of the present application, more or fewer types of diffusing particles may be disposed in the base layer 31, for example, one, three, four, five, etc. types of diffusing particles may be disposed in the base layer 31. In one embodiment, one type of diffusing particle, for example, the first diffusing particles 32, is disposed in the base layer 31, and the particle diameter of the first diffusing particles 32 is relatively large, which makes it easy to form the uneven structure 301 and makes it easier to adjust the haze parameter required for the polarizing filter 20 depending on the number of particles. Furthermore, since the particle size of the first diffusing particles 32 is relatively large and it is easy to form the uneven structure 301, when the dimming film 30 contains two types of diffusing particles, the first diffusing particles 32 and the second diffusing particles 33, the number of the first diffusing particles 32 can be greater than the number of the second diffusing particles 33, and for example, the ratio of the first diffusing particles 32 to the second diffusing particles 33 can be 7:3.

[0042] The polarizing filter 20 is applied to a display panel, and the display panel includes a liquid crystal display panel, etc. In the embodiments of the present application, the display panel is described as a liquid crystal display panel.

[0043] 3, the display panel 100 includes a backlight module 10 and a liquid crystal cell 40 disposed opposite the backlight module 10. The polarizing filter 20 is disposed on the liquid crystal cell 40 closer to the backlight module 10, and the light control film 30 is disposed on the protective layer 21 closer to the backlight module 10. Of course, the display panel 100 further includes an upper polarizing filter 50 disposed on the liquid crystal cell 40 farther from the backlight module 10.

[0044] The backlight module 10 includes a backlight 11, a backplate 12, and an optical film sheet such as a diffusion film 13. The backlight 11 is fixed to the backplate 12, and the diffusion film 13 is disposed in the light emitting direction of the backlight 11. The backplate 12 may be made of a metal material, such as iron or other metal materials, or may be made of an alloy material. In another example of this embodiment, the backplate 12 may be made of a plastic material or an outer frame formed by combining plastic and metal, such as the currently widely used rubber-iron integrated frame.

[0045] The backlight 11 includes a light emitting source such as an LED or a mini LED. The diffusion film 13 is mainly used to uniformly emit light emitted from the backlight 11 at various angles, so as to improve the display uniformity of the display panel 100. Of course, the backlight module 10 may further include a reflective sheet disposed between the backlight 11 and the backplate 12, which is mainly used to improve the light utilization efficiency of the backlight 11, thereby improving the brightness and energy efficiency of the display panel 100.

[0046] The liquid crystal cell 40 includes an array substrate 41 and an opposing substrate 42 disposed opposite each other, and a liquid crystal layer 43 disposed between the array substrate 41 and the opposing substrate 42 .

[0047] The polarizing filter 20 is disposed on the liquid crystal cell 40 on the side closer to the backlight module 10, the light control film 30 is disposed on the protective layer 21 on the side closer to the backlight 11, and the relief structure 301 of the light control film 30 is located on the side closer to the backlight 11. The polarizing filter 20 further includes a compensation layer 23 and an adhesive layer 24 laminated on the polarizing film 22 on the side farther from the protective layer 21. The protective layer 21 is made of polyethylene terephthalate (PET). The protective layer 21 protects the polarizing film 22 and prevents it from being corroded by water and oxygen. The polarizing film 22 is made of polyvinyl alcohol (PVA). Preferably, the adhesive layer 24 is made of a pressure-sensitive adhesive (PSA). The polarizing filter 20 is attached to the side of the liquid crystal cell 40 facing the array substrate 41 by the adhesive layer 24 .

[0048] The structure of the upper polarizing filter 50 is the same as that of the polarizing filter 20, but the upper polarizing filter 50 does not include the light control film 30. The upper polarizing filter 50 can be attached to the opposing substrate 42 side of the liquid crystal cell 40 by an adhesive layer of the upper polarizing filter 50.

[0049] 1 to 4, Fig. 4 is a schematic diagram showing another cross-sectional structure of a display panel according to an embodiment of the present application. The display panel 101 of this embodiment differs from the above-described embodiment in that the uneven surface 301 is provided on the side of the light-control film 30 closer to the protective layer 21. The light-control film 30 includes a base layer 31 and first diffusing particles 32 dispersed in the base layer 31, and at least some of the first diffusing particles 32 protrude from the surface of the light-control film 30 closer to the protective layer 21 to form the uneven surface 301.

[0050] Preferably, the photochromic film 30 may further include a substrate 34, and the substrate layer 31 is disposed on the substrate 34 closer to the protective layer 21, and the substrate 34 may be a glass substrate or the like. Of course, the photochromic film 30 of the present application may not include the substrate 34. For example, after the photochromic film 30 is formed on the substrate 34, the photochromic film 30 is attached to the protective layer 21, and the substrate 34 is removed. Further description will be made with reference to the above examples, and is omitted here.

[0051] 1 to 7, Fig. 5 is a schematic diagram showing another cross-sectional structure of a display panel according to an embodiment of the present application, Fig. 6 is a schematic diagram showing light propagation when the display panel according to an embodiment of the present application does not include a light control film, and Fig. 7 is a schematic diagram showing light propagation when the display panel according to an embodiment of the present application includes a light control film. Different from the above embodiments, in the display panel 102 of this embodiment, as shown in Fig. 5, the backlight module 10 further includes a quantum dot film 14 and a brightness enhancement film 15.

[0052] The quantum dot film 14 is disposed in the emission direction of the backlight 11, the diffusion film 13 is disposed on the side of the quantum dot film 14 farther from the back plate 12, and the brightness enhancement film 15 is disposed on the side of the diffusion film 13 farther from the back plate 12. Of course, the present application is not limited to this, and the quantum dot film 14 of the present application may be disposed between the diffusion film 13 and the brightness enhancement film 15, or may be disposed on the side of the brightness enhancement film 15 farther from the diffusion film 13.

[0053] By disposing the quantum dot film 14 and combining it with the mini LED backlight 11, the QD-Mini LED backlight technology can be used, which uses a local dimming method to realize area light control, achieves ultra-high contrast, and enhances the color gamut of the display panel 102.

[0054] However, referring to FIG. 6, because the QD-Mini LED backlight technology is implemented in the backlight module 10 by the brightness enhancement film 15, all light emitted from the backlight 11 becomes linearly polarized. When the linearly polarized light passes through the protective layer 21 of the polarizing filter 20, the PET of the protective layer 21 has birefringence, causing the linearly polarized light to change polarization state and become elliptically polarized or circularly polarized. Light of different wavelengths passes through the PET and generates output light with different polarization states. When light of different wavelengths passes through the polarizing film 22 again, the light of different wavelengths can be emitted with different light intensity energies, resulting in differences in light intensity energy and significant differences in light transmittance, which in turn exacerbates the rainbow effect. In particular, the QD-Mini LED backlight has a stronger light intensity in the 620nm to 700nm wavelength range than a conventional D65 light source. Combined with the birefringence of the PET itself, the transmitted light intensity in the red wavelength range is stronger, causing a red rainbow effect in the user's vision.

[0055] The polarizing filter 20 of the present application effectively solves the rainbow phenomenon that occurs in QD-Mini LED backlight technology by arranging a dimming film 30 having a concave-convex structure 301 on the side of the protective layer 21 closer to the backlight 11.

[0056] 7 , after the light emitted from the backlight 11 passes through the quantum dot film 14, the light again passes through the irregular concave-convex structure 301 of the light switchable film 30, whereby the light is diffused based on the principle of scattering reflection. The concave-convex structure 301 converts linearly polarized light into partially polarized light, so that the light emitted from the light switchable film 30 is no longer linearly polarized, and the light is scattered uniformly, effectively diffusing the light intensity energy, thereby making the distribution of the light intensity energy of the light emitted from the light switchable film 30 more uniform. When the partially polarized light emitted from the light switchable film 30 passes through the protective layer 21, no change in polarization state occurs. When light of different wavelengths again passes through the polarizing film 22, the light intensity energy that can be emitted from different wavelengths is the same, so that the light intensity energy of each wavelength is uniformly distributed, and the rainbow phenomenon is avoided.

[0057] 6 and 7 are schematic illustrations of the propagation direction of light and the state of light after passing through different film layers. The general positional relationship of each film layer is simply shown to clearly show the propagation direction and state of light after passing through different film layers, but they do not represent the actual film layer structure. Also, the arrowed lines in FIGS. 6 and 7 represent the propagation direction of light, and the diagonal lines, circles, and ellipses represent the state of light. Further explanations will be given with reference to the above examples, and are omitted here.

[0058] Based on the same inventive concept, an embodiment of the present application further provides a method for manufacturing a polarizing filter, which can be used to manufacture any one of the polarizing filters of the above embodiments, and the polarizing filter manufactured by the method for manufacturing a polarizing filter can be applied to any one of the display panels of the above embodiments. Specifically, referring to Figures 1 to 8, Figure 8 is a flow diagram showing a method for manufacturing a polarizing filter according to an embodiment of the present application. Referring to Figure 8, the method for manufacturing a polarizing filter includes the following steps:

[0059] In S201, a protective layer 21 is attached to one side of a polarizing film 22.

[0060] 1 and 3, the protective layer 21 is attached to one side of the polarizing film 22, and the compensation layer 23 and the adhesive layer 24 are attached to the side of the polarizing film 22 away from the protective layer 21. The material of the protective layer 21 includes polyethylene terephthalate. The protective layer 21 is used to protect the polarizing film 22 and prevent the polarizing film 22 from being corroded by water and oxygen. The material of the polarizing film 22 includes polyvinyl alcohol (PVA). Preferably, the material of the adhesive layer 24 is a pressure-sensitive adhesive (PSA).

[0061] In S202, a concave-convex structure 301 is formed on the side of the protective layer 21 farther from the polarizing film 22, and the concave-convex structure 301 includes a plurality of sub-convex surfaces 310 with different shapes and / or sizes.

[0062] Specifically, the step of forming the concave-convex structure 301 on the side of the protective layer 21 farther from the polarizing film 22 includes the following steps.

[0063] The light control liquid is formed by mixing the UV curable resin, the UV curable monomer, the first diffusing particles 32, and the second diffusing particles 33 in a solvent. Specifically, the light control liquid is formed by mixing the UV curable resin, the UV curable monomer, the first diffusing particles 32, the second diffusing particles 33, the photosensitizer, and other auxiliary agents in a solvent.

[0064] Here, the UV-curable resin includes, for example, an epoxy acrylate oligomer or a urethane acrylate oligomer having a molecular weight of several hundred to several tens of thousands, and the UV-curable monomer includes at least one of trimethylolpropane acrylate (TMPTA), pentaerythritol tetraacrylate (PETA), dipentaerythritol penta / hexaacrylate (DPHA), etc.

[0065] The photosensitizer includes at least one of a benzophenone-based photosensitizer, a thioxanthone-based photosensitizer, etc., and the proportion of the photosensitizer is 1% to 4%. Other adjuvants include a thickener, a leveling agent, an antistatic agent, etc., and the proportion of the other adjuvants is 0.1% to 1%. The thickener is used to adjust the viscosity of the product, the leveling agent is used to improve the appearance of the product, and the antistatic agent is used to reduce the surface resistance of the coating. The solvent includes a ketone-based solvent, an alcohol-based solvent, a lipid-based solvent, an ether-based solvent, etc.

[0066] The first diffusing particles 32 include polymethyl methacrylate particles with a particle size of 2 μm to 3 μm, and the second diffusing particles 33 include at least one type of inorganic particles such as silica dioxide particles, titanium dioxide particles, and zinc dioxide particles with a particle size of 30 nm to 70 nm. The mass fraction of the first diffusing particles 32 to the second diffusing particles 33 in the light control solution ranges from 2.5% to 20%. If the ratio of the first diffusing particles 32 to the second diffusing particles 33 is small, the haze effect of the formed light control film 30 is poor, which in turn results in a poor haze effect of the formed polarizing plate 20, affecting the effectiveness of preventing iridescence. If the ratio of the first diffusing particles 32 to the second diffusing particles 33 is large, when the formed polarizing filter 20 is applied to the display panel 100, light diffusion becomes too severe, resulting in reduced contrast and transmittance of the display panel 100. Preferably, the ratio of the first diffusing particles 32 to the second diffusing particles 33 is 7:3.

[0067] The photochromic liquid is coated on the side of the protective layer 21 farther from the polarizing film 22 .

[0068] Specifically, the light-controlling liquid is coated on the side of the protective layer 21 farther from the polarizing film 22 using a coating process such as wet coating.

[0069] The photochromic liquid is cured to form a photochromic film, and one side of the photochromic film forms the uneven structure 301. Specifically, the photochromic liquid coated on one side of the protective layer 21 is cured, a base layer 31 is formed with the UV-curable resin, the first diffusing particles 32 and the second diffusing particles 33 are dispersed in the base layer 31, and at least some of the first diffusing particles 32 protrude from the side of the base layer 31 far from the protective layer 21 to form the uneven structure 301, and the second diffusing particles 33 and the first diffusing particles 32 protrude from the surface of the same side of the base layer 31, and some of the first diffusing particles 32 are located on the side of the second diffusing particles 33 far from the uneven structure 301 to form the photochromic film 30, as shown in FIG.

[0070] In another embodiment, in step S202, the step of forming the concave-convex structure 301 on the side of the protective layer 21 farther from the polarizing film 22 can also be realized by the following method.

[0071] The side of the protective layer 21 far from the polarizing film 22 is etched using a photo-etching process to form the uneven surface structure 301. That is, the uneven surface structure 301 is directly formed on the protective layer 21 by directly etching one side of the protective layer 21. Further description will be given with reference to the above embodiment and is omitted here.

[0072] In another embodiment, in step S202, the step of forming the concave-convex structure 301 on the side of the protective layer 21 farther from the polarizing film 22 can also be realized by the following method.

[0073] 4, a photochromic liquid is coated on a substrate 34 and cured to form a photochromic film 30, and the uneven surface 301 is formed on the side of the photochromic film 30 away from the substrate 34. Specifically, the photochromic liquid coated on one side of the substrate 34 is cured, and the UV-curable resin forms a substrate layer 31. The first diffusing particles 32 and the second diffusing particles 33 are dispersed in the substrate layer 31, and at least some of the first diffusing particles 32 protrude from the side of the substrate layer 31 away from the protective layer 21 to form the uneven surface 301. The second diffusing particles 33 and the first diffusing particles 32 protrude from the surface of the same side of the substrate layer 31, and as shown in FIG. 4, some of the first diffusing particles 32 are located on the side of the second diffusing particles 33 away from the uneven surface 301 to form the photochromic film 30.

[0074] After the light-controlling film 30 is formed, the light-controlling film 30 is attached to the side of the protective layer 21 farther from the polarizing film 22. Of course, the light-controlling film 30 of the present application may not include the substrate 34. For example, after the light-controlling film 30 is formed on the substrate 34, the light-controlling film 30 is attached to the protective layer 21, and the substrate 34 is removed.

[0075] The above example reveals the following.

[0076] The present application provides a polarizing filter, a manufacturing method thereof, and a display panel, the polarizing filter including a polarizing film, a protective layer, and a light-control film, the protective layer being disposed on one side of the polarizing film and the light-control film being disposed on the side of the protective layer farther from the polarizing film, the light-control film having a concave-convex structure including a plurality of sub-convex surfaces of different shapes and / or sizes. By disposing the concave-convex structure on the side of the protective layer farther from the polarizing film, the present application provides a method for uniformly scattering light passing through the concave-convex structure based on the principle of diffuse reflection when light traveling toward the polarizing filter passes through the concave-convex structure, and when the uniformly scattered light passes through the protective layer again, the energy of the light intensity of each wavelength is uniformly dispersed, thereby avoiding the occurrence of rainbow unevenness and resolving the technical problem of rainbow unevenness in conventional display devices.

[0077] In the above examples, the explanation of each example is focused on, and for parts that are not mentioned in detail in some examples, please refer to the related explanations of other examples.

[0078] Although the embodiments of the present application have been described in detail above and specific examples have been used to explain the principles and embodiments of the present application, the explanation of the above embodiments is intended to facilitate understanding of the technical solutions and core ideas of the present application. Those skilled in the art should understand that modifications can be made to the technical ideas described in the above embodiments or some of the technical features can be replaced with equivalents, and such modifications or replacements do not deviate from the essence of the corresponding technical solutions and the scope of the technical solutions of the various embodiments of the present application.

Claims

1. A polarizing film; a protective layer disposed on one side of the polarizing film; wherein the protective layer has a concave-convex structure on a side farther from the polarizing film, the concave-convex structure including a plurality of sub-convex surfaces having different shapes and / or sizes. Polarizing filter.

2. The polarizing filter further includes a light-control film disposed on a side of the protective layer farther from the polarizing film, and one side of the light-control film has the uneven structure. The polarizing filter according to claim 1 .

3. the side of the light-control film farther from the protective layer has the uneven structure; The photochromic film includes a base layer and first diffusing particles dispersed in the base layer, and at least some of the first diffusing particles protrude from a surface of the photochromic film farther from the protective layer to form the uneven structure. The polarizing filter according to claim 2 .

4. the side of the light-control film closer to the protective layer has the uneven structure; The photochromic film includes a base layer and first diffusing particles dispersed in the base layer, and at least some of the first diffusing particles protrude from a surface of the photochromic film closer to the protective layer to form the uneven structure. The polarizing filter according to claim 2 .

5. The photochromic film further includes second diffusing particles dispersed in the base layer, the second diffusing particles and the first diffusing particles protrude from the same surface of the photochromic film, and at least some of the first diffusing particles are located on a side of the second diffusing particles farther from the uneven structure. The polarizing filter according to claim 3 .

6. The particle size of the first diffusion particles is larger than the particle size of the second diffusion particles. The polarizing filter according to claim 5 .

7. the substrate layer includes an ultraviolet curable resin substrate, the first diffusing particles include polymethyl methacrylate particles, and the second diffusing particles include at least one of silicon dioxide particles, titanium dioxide particles, and zinc dioxide particles; The polarizing filter according to claim 6.

8. The haze range of the polarizing filter is 20% to 70%. The polarizing filter according to claim 2 .

9. an angle between a normal to each of the plurality of sub-convex and concave surfaces and a plane parallel to a plane on which the protective layer is located ranges from 0° to 180°; The polarizing filter according to claim 1 .

10. applying a protective layer to one side of the polarizing film; forming a concave-convex structure on a side of the protective layer farther from the polarizing film, the concave-convex structure including a plurality of sub-convex surfaces having different shapes and / or sizes; How to make a polarizing filter.

11. The step of forming a concavo-convex structure on the side of the protective layer farther from the polarizing film includes: mixing an ultraviolet curable resin, an ultraviolet curable monomer, and first diffusing particles in a solvent to form a light control liquid; coating the photochromic liquid on the side of the protective layer farther from the polarizing film; hardening the photochromic liquid to form the photochromic film, and forming the uneven structure on one side of the photochromic film; A method for producing the polarizing filter according to claim 10.

12. The photochromic liquid further comprises second diffusing particles, the particle size of the second diffusing particles being smaller than the particle size of the first diffusing particles, the second diffusing particles comprising inorganic silicon dioxide particles having a particle size of 30 nm to 70 nm, and the first diffusing particles comprising polymethyl methacrylate particles having a particle size of 2 μm to 3 μm; A method for producing the polarizing filter according to claim 11.

13. The mass fraction of the first diffusing particles and the second diffusing particles in the photochromic solution is in the range of 2.5% to 20%, and the ratio of the first diffusing particles to the second diffusing particles is 7:

3. A method for producing the polarizing filter according to claim 12.

14. a polarizing filter, the polarizing filter comprising: A polarizing film; a protective layer disposed on one side of the polarizing film; wherein the protective layer has a concave-convex structure on a side farther from the polarizing film, the concave-convex structure including a plurality of sub-convex surfaces having different shapes and / or sizes. Display panel.

15. The polarizing filter further includes a light-control film disposed on a side of the protective layer farther from the polarizing film, and one side of the light-control film has the uneven structure. The display panel according to claim 14.

16. the side of the light-control film farther from the protective layer has the uneven structure; The photochromic film includes a base layer and first diffusing particles dispersed in the base layer, and at least some of the first diffusing particles protrude from a surface of the photochromic film farther from the protective layer to form the uneven structure. The display panel according to claim 15.

17. the side of the light-control film closer to the protective layer has the uneven structure; The photochromic film includes a base layer and first diffusing particles dispersed in the base layer, and at least some of the first diffusing particles protrude from a surface of the photochromic film closer to the protective layer to form the uneven structure. The display panel according to claim 15.

18. The photochromic film further includes second diffusing particles dispersed in the base layer, the second diffusing particles and the first diffusing particles protrude from the same surface of the photochromic film, and at least some of the first diffusing particles are located on a side of the second diffusing particles farther from the uneven structure. The display panel according to claim 16.

19. The haze range of the polarizing filter is 20% to 70%. The display panel according to claim 15.

20. an angle between a normal to each of the plurality of sub-convex and concave surfaces and a plane parallel to a plane on which the protective layer is located ranges from 0° to 180°; The display panel according to claim 14.

Images