Light diffusion film, polarizer, and display device

Abstract

To increase the viewing angle of a polarizer by means of refraction of light beams due to light diffusion particles; avoid the decrease of emitted light beams caused by providing an additional film layer to the polarizer; and increase the light emission rate of a display device having a light diffusion film while improving the chromaticity viewing angle and the contrast of the display device.SOLUTION: A light diffusion film 101 includes a substrate 1011 and light diffusion particles 1012 dispersed in the substrate 1011, where the mass fraction of the light diffusion particles 1012 in the substrate 1011 is less than 3%.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to the display field, and more particularly to a light diffusing film, a polarizing plate and a display device. [Background technology]

[0002] At present, in order to expand the chromaticity viewing angle of a display device, an optical film for expanding the chromaticity viewing angle is usually installed on the outermost side of a polarizing plate. Conventional optical films for expanding the chromaticity viewing angle require an additional film layer corresponding to the polarizing plate (for example, a patterned high refractive index layer and a patterned low refractive index layer are overlapped), which complicates the process, increases the thickness of the polarizing plate, and reduces the output light of the display device, thereby degrading the display contrast of the display device.

[0003] Therefore, there is a demand for a light diffusion film, a polarizing plate, and a display device that can solve the above problems. Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention provides a light diffusion film, a polarizing plate, and a display device to alleviate the problem of degradation of the display contrast of a display device due to a reduction in the output light of the display device by adding a film layer to the polarizing plate. [Means for solving the problem]

[0005] The light diffusion film provided by the present invention includes a substrate and light diffusion particles dispersed in the substrate, the mass fraction of the light diffusion particles in the substrate being less than 3%.

[0006] Preferably, the light diffusing particles include a first type light diffusing particle, the first type light diffusing particle includes a plurality of first cross sections, each of the first cross sections includes one first circumscribing circle, the ratio of the long axis length of the first type light diffusing particle to the diameter of the first circumscribing circle having the largest diameter among the plurality of first circumscribing circles is 5 or more, the ratio of the long axis length of the first type light diffusing particle to the diameter of the first circumscribing circle having the largest diameter among the plurality of first circumscribing circles is less than 100, and the first cross sections are perpendicular to the extension direction of the long axis of the first light diffusing particle.

[0007] Preferably, the first type light diffusing particles are at least one selected from a first subtype light diffusing particle, a second subtype light diffusing particle, a third subtype light diffusing particle, a fourth subtype light diffusing particle, and a fifth subtype light diffusing particle, which have different shapes from each other, and a change value of a diameter of a first circumscribed circle of the first cross section of the first subtype light diffusing particle along an extension direction of a major axis of the first subtype light diffusing particle is 0.3 micrometers or less, and a front part located at a middle part of the second subtype light diffusing particle along an extension direction of a major axis of the second subtype light diffusing particle is 0.2 micrometers or less. a change in diameter of the first circumscribing circle of the first cross section is 1 micrometer or less, the diameter of the first circumscribing circle of the first cross section located at a first end of the second subtype light diffusing particle gradually decreases along a direction away from a middle portion of the second subtype light diffusing particle, a change in diameter of the first circumscribing circle of the first cross section located at a second end of the second subtype light diffusing particle is 1 micrometer or less, and a change in diameter of the first circumscribing circle of the first cross section located at a middle portion of the third subtype light diffusing particle along an extension direction of a major axis of the third subtype light diffusing particle is 1 the diameter of the first circumscribing circle of the first cross section located at a first end of the third subtype light diffusing particle gradually decreases along a direction away from an intermediate portion of the third subtype light diffusing particle, the diameter of the first circumscribing circle of the first cross section located at a second end of the third subtype light diffusing particle gradually decreases, the first end of the fourth subtype light diffusing particle is connected to the second end of the fourth subtype light diffusing particle, and the diameter of the first circumscribing circle of the first cross section located at a first end of the third subtype light diffusing particle gradually decreases along a direction away from an intermediate portion of the third subtype light diffusing particle, the first end of the fourth subtype light diffusing particle is connected to the second end of the fourth subtype light diffusing particle, a diameter of a first circumscribing circle of the first cross section of the fifth subtype light diffusing particle gradually decreases, a first end of the fifth subtype light diffusing particle is connected to a second end of the fifth subtype light diffusing particle, a diameter of a first circumscribing circle of the first cross section located at the first end of the fifth subtype light diffusing particle gradually decreases along a direction away from the second end of the fifth subtype light diffusing particle, and a diameter of a first circumscribing circle of the first cross section located at the second end of the fifth subtype light diffusing particle gradually decreases along a direction away from the first end of the fifth subtype light diffusing particle.

[0008] Preferably, the light diffusing particles further include a second type of light diffusing particle, the second type of light diffusing particle includes a plurality of second cross sections, each of the second cross sections includes one second circumscribing circle, the ratio of the long axis length of the second type of light diffusing particle to the diameter of the second circumscribing circle having the largest diameter among the plurality of second circumscribing circles is 1 or more, the ratio of the long axis length of the second type of light diffusing particle to the diameter of the second circumscribing circle having the largest diameter among the plurality of second circumscribing circles is less than 5, and the second cross sections are perpendicular to the extension direction of the long axis of the second type of light diffusing particle.

[0009] Preferably, the second type light diffusing particles are at least one selected from the group consisting of sixth subtype light diffusing particles and seventh subtype light diffusing particles, which have different shapes from each other, and the second type light diffusing particles are at least one selected from the group consisting of the sixth subtype light diffusing particles, the seventh subtype light diffusing particles, the eighth subtype light diffusing particles, the ninth subtype light diffusing particles, and the tenth subtype light diffusing particles, which have different shapes from each other, and the change in diameter of the second circumscribing circle of the second cross section of the sixth subtype light diffusing particle along the extension direction of the major axis of the sixth subtype light diffusing particle is 0.a first end of the 7th subtype light diffusing particle is connected to a second end of the 7th subtype light diffusing particle, a diameter of a second circumscribing circle of the second cross section located at the first end of the 7th subtype light diffusing particle gradually decreases along a direction away from the second end of the 7th subtype light diffusing particle, a diameter of a second circumscribing circle of the second cross section located at the second end of the 7th subtype light diffusing particle gradually decreases along a direction away from the first end of the 7th subtype light diffusing particle, a change value of a diameter of a second circumscribing circle of the second cross section located at a middle part of the 8th subtype light diffusing particle along an extension direction of a major axis of the 8th subtype light diffusing particle is 1 micrometer or less, a diameter of a second circumscribing circle of the second cross section located at the first end of the 8th subtype light diffusing particle gradually decreases along a direction away from the middle part of the 8th subtype light diffusing particle, a change in diameter of the second circumscribing circle of the second cross section located at the second end of the 9th subtype light diffusing particle is 1 micrometer or less, a change in diameter of the second circumscribing circle of the second cross section located at the middle part of the 9th subtype light diffusing particle is 1 micrometer or less along the extension direction of the major axis of the 9th subtype light diffusing particle, a change in diameter of the second circumscribing circle of the second cross section located at the first end of the 9th subtype light diffusing particle gradually decreases along a direction away from the middle part of the 9th subtype light diffusing particle, a change in diameter of the second circumscribing circle of the second cross section located at the second end of the 9th subtype light diffusing particle gradually decreases, a first end of the 10th subtype light diffusing particle is connected to the second end of the 10th subtype light diffusing particle, and a change in diameter of the second circumscribing circle of the second cross section of the 10th subtype light diffusing particle gradually decreases along a direction from the first end of the 10th subtype light diffusing particle to the second end of the 10th subtype light diffusing particle.

[0010] Preferably, the first subtype light diffusing particle is selected from rod-shaped particles, the second subtype light diffusing particle is selected from needle-shaped particles having a smaller diameter at one end, the third subtype light diffusing particle is selected from needle-shaped particles having smaller diameters at both ends, the fourth subtype light diffusing particle is selected from long tapered particles, the fifth subtype light diffusing particle is selected from double tapered particles and / or oval-spherical particles, the sixth subtype light diffusing particle is selected from cuboidal particles or rectangular parallelepiped particles, the seventh subtype light diffusing particle is selected from spherical particles or ellipsoidal particles, the eighth subtype light diffusing particle is selected from needle-shaped particles having a smaller diameter at one end, the ninth subtype light diffusing particle is selected from needle-shaped particles having smaller diameters at both ends, and the tenth subtype light diffusing particle is selected from long tapered particles.

[0011] Preferably, the mass fraction of the fifth subtype light diffusing particles in the light diffusing particles is 20% or more, and the mass fraction of the fifth subtype light diffusing particles in the light diffusing particles is 100% or less.

[0012] Preferably, the light diffusing particles have an average particle diameter, the long axis length of any of the light diffusing particles is 20% or more of the average particle diameter of the light diffusing particles, and the long axis length of any of the light diffusing particles is 180% or less of the average particle diameter of the light diffusing particles.

[0013] Preferably, the substrate includes a first sub-substrate and / or a second sub-substrate, the first sub-substrate being at least one selected from unmodified polyester and unmodified acetate fiber, the second sub-substrate being at least one selected from modified polyester and modified acetate cellulose, the mass fraction of the first sub-substrate in the substrate being 65% or more, the mass fraction of the first sub-substrate in the substrate being 100% or less, the mass fraction of the second sub-substrate in the substrate being 0% or more, and the mass fraction of the second sub-substrate in the substrate being 35% or less.

[0014] The present invention further provides a polarizing plate, which comprises the light diffusing film.

[0015] The present invention further provides a display device, which includes the polarizing plate. Effect of the Invention

[0016] The present invention adds light diffusing particles having a mass fraction of less than 3% to the substrate of a light diffusing film, thereby utilizing the refraction effect of the light diffusing particles on light rays to improve the viewing angle of the polarizing plate, avoiding the reduction in emitted light rays caused by adding an additional film layer to the polarizing plate, and further improving the chromaticity viewing angle and contrast of a display device having a light diffusing film, as well as improving the light output rate of the display device. [Brief description of the drawings]

[0017] In order to more clearly describe the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can also obtain other drawings based on these drawings without creative efforts.

[0018] [Figure 1] FIG. 1 is a first structural schematic diagram of a light diffusion film provided in an embodiment of the present invention. [Diagram 2] FIG. 2 is a second structural schematic diagram of the light diffusion film provided in the embodiment of the present invention. [Diagram 3] FIG. 2 is a first structural schematic diagram of a polarizing plate provided in an embodiment of the present invention; [Figure 4] FIG. 2 is a second structural schematic diagram of a polarizing plate provided in an embodiment of the present invention. [Diagram 5] FIG. 3 is a third structural schematic diagram of a polarizing plate provided in an embodiment of the present invention. [Figure 6] FIG. 4 is a fourth structural schematic diagram of a polarizing plate provided in an embodiment of the present invention. [Figure 7] FIG. 2 is a structural schematic diagram of a display device provided in an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, and are not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts also belong to the protection scope of the present invention. It should also be understood that the specific embodiments described herein are for explaining and interpreting the present invention, and do not limit the present invention. In the present invention, unless otherwise described, the directional terms "up" and "down" used generally refer to the up and down of the device in the actual use or operation state, specifically the drawing direction in the drawing, and "inside" and "outside" refer to the contour of the device.

[0020] Currently, optical films for expanding the chromaticity viewing angle require the addition of a film layer corresponding to a polarizing plate, which reduces the light emitted from the display device and deteriorates the display contrast, resulting in a decrease in the display quality of the display device.

[0021] Referring to Figures 1 and 2, the light diffusion film 101 provided by the present invention includes a substrate 1011 and light diffusion particles 1012 dispersed in the substrate 1011, and the mass fraction of the light diffusion particles 1012 in the substrate 1011 is less than 3%.

[0022] In an embodiment of the present invention, by adding light diffusing particles 1012 having a mass fraction of less than 3% to the substrate 1011 of the light diffusing film 101, the viewing angle of the polarizing plate can be improved by utilizing the refraction effect of the light diffusing particles 1012 on the light, thereby avoiding the reduction in the emitted light caused by adding an additional film layer to the polarizing plate, and further improving the chromaticity viewing angle and contrast of a display device having the light diffusing film 101, as well as improving the light output rate of the display device.

[0023] The technical solution of the present invention will now be described with reference to specific embodiments.

[0024] 1 and 2, in this embodiment, the light diffusion particle 1012 has a major axis and a diameter, the major axis length of the light diffusion particle 1012 is the distance between both ends of the major axis of the light diffusion particle 1012, each light diffusion particle 1012 includes a plurality of cross sections in the extension direction perpendicular to the major axis of the light diffusion particle 1012, each cross section includes a circumscribing circle, and the diameter of the light diffusion particle 1012 corresponds to the diameter of the circumscribing circle with the largest diameter among the plurality of cross sections. Here, the two points on one cross section of the light diffusion particle 1012 that are the furthest apart are located on the circumscribing circle of the cross section, and the distance between the two points on the cross section that are the furthest apart is the diameter of the circumscribing circle. The light diffusion particle 1012 includes a first type light diffusion particle 1012a.

[0025] Here, the first type light diffusing particle 1012a includes a plurality of first cross sections, each of the first cross sections includes one first circumscribing circle, the ratio of the long axis length of the first type light diffusing particle 1012a to the diameter of the first circumscribing circle having the largest diameter among the plurality of first circumscribing circles is 5 or more, the ratio of the long axis length of the first type light diffusing particle 1012a to the diameter of the first circumscribing circle having the largest diameter among the plurality of first circumscribing circles is less than 100, and the first cross section is perpendicular to the extension direction of the long axis of the first type light diffusing particle 1012a, and may be, for example, 10, 12, 15, 16, 18, 20, 30, 32, 34, 35, 36, 38, 40, 42, 45, 46, 48, 50, 52, 55, 56, 58, 60, 62, 65, 68, 70, 80, 90, etc. The diameter of the first circumscribing circle of one of the first cross sections of the first type light diffusion particles 1012a is the distance between the two points on the first cross section that are the furthest apart. By using the first type light diffusion particles 1012a having a larger aspect ratio (the ratio between the major axis length and the diameter of the first circumscribing circle with the largest diameter), more light rays can easily change the propagation direction through the light diffusion particles 1012, so that the light diffusion particles 1012 can achieve an improvement effect on chromaticity, viewing angle and contrast.

[0026] In some embodiments, the first type light diffusing particles 1012a are at least one selected from a first subtype light diffusing particle, a second subtype light diffusing particle, a third subtype light diffusing particle, a fourth subtype light diffusing particle, and a fifth subtype light diffusing particle, which have different shapes from each other.

[0027] Here, the change value of the diameter of the first circumscribing circle of the first cross section of the first subtype light diffusing particle along the extension direction of the long axis of the first subtype light diffusing particle may be 0.3 micrometers or less, for example, 0 micrometers, 0.28 micrometers, 0.25 micrometers, 0.22 micrometers, 0.2 micrometers, 0.18 micrometers, 0.15 micrometers, 0.12 micrometers, 0.1 micrometers, 0.08 micrometers, 0.05 micrometers, 0.02 micrometers, etc. In some embodiments, along the extension direction of the long axis of the first subtype light diffusing particle, the diameter of the first circumscribing circle of the first cross section located at a first end of the first subtype light diffusing particle is the same as the diameter of the first circumscribing circle of the first cross section located at a middle part of the first subtype light diffusing particle, and the diameter of the first circumscribing circle located at a second end of the first subtype light diffusing particle is the same as the diameter of the first circumscribing circle located at a middle part of the first subtype light diffusing particle.

[0028] In some embodiments, the first cross-section of the first sub-type light diffusing particles may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a square, etc.

[0029] In some embodiments, the first subtype light diffusing particles may be rod-shaped particles, and when the first subtype light diffusing particles are rod-shaped, the first cross section of the first subtype light diffusing particles may be circular or elliptical. When the first cross section of the first subtype light diffusing particles is circular, the first circumscribing circle of the first cross section of the first subtype light diffusing particles may overlap with the first cross section. When the first cross section of the first subtype light diffusing particles is elliptical, the diameter of the first circumscribing circle of each of the first cross sections of the first subtype light diffusing particles is the major axis length of the ellipse of each of the first cross sections of the first subtype light diffusing particles, and the ratio of the major axis of the ellipse of one of the first cross sections of one of the first subtype light diffusing particles to the minor axis of the ellipse of the first cross section of the first subtype light diffusing particles may be greater than 1 and less than or equal to 3, for example, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, etc.

[0030] A change in diameter of a first circumscribing circle of the first cross section located at an intermediate portion of the second subtype light diffusing particle along an extension direction of the long axis of the second subtype light diffusing particle is 1 micrometer or less, for example, 0 micrometer, 0.95 micrometer, 0.8 micrometer, 0.78 micrometer, 0.75 micrometer, 0.72 micrometer, 0.7 micrometer, 0.68 micrometer, 0.65 micrometer, 0.62 micrometer, 0.6 micrometer, 0.58 micrometer, 0.55 micrometer, 0.52 micrometer. , 0.5 micrometers, 0.48 micrometers, 0.45 micrometers, 0.42 micrometers, 0.4 micrometers, 0.38 micrometers, 0.35 micrometers, 0.32 micrometers, 0.3 micrometers, 0.28 micrometers, 0.25 micrometers, 0.22 micrometers, 0.2 micrometers, 0.18 micrometers, 0.15 micrometers, 0.12 micrometers, 0.1 micrometers, 0.08 micrometers, 0.05 micrometers, 0.02 micrometers, and the like.Along a direction away from the intermediate portion of the second subtype light diffusing particle, a diameter of a first circumscribing circle of the first cross section located at a first end of the second subtype light diffusing particle becomes smaller, and a change value of the diameter of the first circumscribing circle of the first cross section located at a second end of the second subtype light diffusing particle is 1 micrometer or less, for example, 0 micrometer, 0.95 micrometer, 0.8 micrometer, 0.78 micrometer, 0.75 micrometer, 0.72 micrometer, 0.7 micrometer, 0.68 micrometer, 0.65 micrometer, 0.62 micrometer, 0.6 micrometer, 0.58 micrometer. , 0.55 micrometers, 0.52 micrometers, 0.5 micrometers, 0.48 micrometers, 0.45 micrometers, 0.42 micrometers, 0.4 micrometers, 0.38 micrometers, 0.35 micrometers, 0.32 micrometers, 0.3 micrometers, 0.28 micrometers, 0.25 micrometers, 0.22 micrometers, 0.2 micrometers, 0.18 micrometers, 0.15 micrometers, 0.12 micrometers, 0.1 micrometers, 0.08 micrometers, 0.05 micrometers, 0.02 micrometers, etc. In some embodiments, along a direction away from a middle portion of the second subtype light diffusing particle, a diameter of a first circumscribing circle of the first cross section located at a first end of the second subtype light diffusing particle becomes smaller, and a diameter of a first circumscribing circle of the first cross section located at a second end of the second subtype light diffusing particle is the same as a diameter of a first circumscribing circle of the first cross section located at a middle portion of the second subtype light diffusing particle.

[0031] As can be understood, this includes, but is not limited to, that the diameter of the first circumscribing circle of the first cross section located at the first end of the second subtype light diffusing particle becomes smaller along the direction away from the middle part of the second subtype light diffusing particle, that the diameter of the first circumscribing circle of the first cross section located at the first end of the second subtype light diffusing particle tends to become smaller in the direction away from the middle part of the second subtype light diffusing particle, and that the diameter of the first circumscribing circle of the first cross section located at the first end of the second subtype light diffusing particle gradually becomes smaller in the direction away from the middle part of the second subtype light diffusing particle.

[0032] In some embodiments, the first cross-section of the second sub-type light diffusing particles may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a square, etc.

[0033] In some embodiments, the second sub-type light diffusing particles may be needle-shaped particles with a smaller diameter at one end.

[0034] In some embodiments, when the second subtype light diffusing particle is a needle-shaped particle with a smaller diameter at one end, the first cross section of the second subtype light diffusing particle may be circular or elliptical. When the first cross section located at the second end of the second subtype light diffusing particle or the first cross section located at the middle part of the second subtype light diffusing particle is elliptical, the ratio of the major axis of the ellipse of the first cross section located at either the second end or the middle part of the second subtype light diffusing particle to the minor axis of the ellipse is greater than 1 and less than or equal to 3, for example, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, etc. The shape of the first cross section located at the first end of the second subtype light diffusing particle is the same as the shape of the first cross section located at the middle part of the second subtype light diffusing particle, and the area decreases along the direction away from the middle part of the second subtype light diffusing particle.

[0035] The change in diameter of the first circumscribing circle of the first cross section located at the middle of the third subtype light diffusing particle along the extension direction of the major axis of the third subtype light diffusing particle is 1 micrometer or less, for example, 0 micrometers, 0.95 micrometers, 0.8 micrometers, 0.78 micrometers, 0.75 micrometers, 0.72 micrometers, 0.7 micrometers, 0.68 micrometers, 0.65 micrometers, 0.62 micrometers, 0.6 micrometers, 0.58 micrometers, 0.55 micrometers, 0.52 micrometers. , 0.5 micrometers, 0.48 micrometers, 0.45 micrometers, 0.42 micrometers, 0.4 micrometers, 0.38 micrometers, 0.35 micrometers, 0.32 micrometers, 0.3 micrometers, 0.28 micrometers, 0.25 micrometers, 0.22 micrometers, 0.2 micrometers, 0.18 micrometers, 0.15 micrometers, 0.12 micrometers, 0.1 micrometers, 0.08 micrometers, 0.05 micrometers, 0.02 micrometers, etc. Along a direction away from the intermediate portion of the third subtype light diffusing particle, a diameter of a first circumscribing circle of the first cross section located at a first end of the third subtype light diffusing particle becomes smaller, and a diameter of a first circumscribing circle of the first cross section located at a second end of the third subtype light diffusing particle becomes smaller. In some embodiments, along the extension direction of the long axis of the third subtype light diffusing particle, the diameter of the first circumscribing circle of the first cross section located at the middle part of the third subtype light diffusing particle is uniform, and the diameters of the first circumscribing circle of the first cross section located at the first end part of the third subtype light diffusing particle and located at the second end part of the third subtype light diffusing particle vary.

[0036] As can be understood, this includes, but is not limited to, that the diameter of the first circumscribing circle of the first cross section located at the first end of the third subtype light diffusing particle becomes smaller along the direction away from the middle part of the third subtype light diffusing particle, that the diameter of the first circumscribing circle of the first cross section located at the first end of the third subtype light diffusing particle tends to become smaller in the direction away from the middle part of the third subtype light diffusing particle, and that the diameter of the first circumscribing circle of the first cross section located at the first end of the third subtype light diffusing particle gradually becomes smaller in the direction away from the middle part of the third subtype light diffusing particle.

[0037] As can be understood, the diameter of the first circumscribing circle of the first cross section located at the second end of the third subtype light diffusing particle tends to become smaller along the direction away from the middle part of the third subtype light diffusing particle, and the diameter of the first circumscribing circle of the first cross section located at the second end of the third subtype light diffusing particle tends to become smaller in the direction away from the middle part of the third subtype light diffusing particle, including, but not limited to, the diameter of the first circumscribing circle of the first cross section located at the second end of the third subtype light diffusing particle gradually becomes smaller in the direction away from the middle part of the third subtype light diffusing particle.

[0038] In some embodiments, the first cross-section of the third sub-type light diffusing particles may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a square, etc.

[0039] In some embodiments, the third sub-type light diffusing particles may be needle-shaped particles with decreasing diameters at both ends.

[0040] In some embodiments, when the third subtype light diffusing particles are needle-shaped particles with smaller diameters at both ends, the shape of the first cross section of the third subtype light diffusing particles may be circular or elliptical. When the first cross section located at the middle part of the third subtype light diffusing particles is elliptical, the ratio of the major axis of the ellipse of the first cross section located at any part of the middle part of the third subtype to the minor axis of the ellipse is greater than 1 and less than or equal to 3, for example, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, etc. The shape of the first cross section located at the first end of the third subtype light diffusing particle and at the second end of the third subtype light diffusing particle is the same as the shape of the first cross section located at the middle part of the third subtype light diffusing particle, and the area decreases along the direction away from the middle part of the third subtype light diffusing particle.

[0041] A first end of the fourth subtype light diffusing particle is connected to a second end of the fourth subtype light diffusing particle, and a diameter of a first circumscribing circle of the first cross section of the fourth subtype light diffusing particle becomes smaller along a direction from the first end of the fourth subtype light diffusing particle to the second end of the fourth subtype light diffusing particle.

[0042] As can be understood, the diameter of the first circumscribing circle of the first cross section of the fourth subtype light diffusing particle decreases along the direction from the first end of the fourth subtype light diffusing particle to the second end of the fourth subtype light diffusing particle, and the diameter of the first circumscribing circle of the first cross section of the fourth subtype light diffusing particle tends to decrease in the direction from the first end of the fourth subtype light diffusing particle to the second end of the fourth subtype light diffusing particle, including, but not limited to, the diameter of the first circumscribing circle of the first cross section of the fourth subtype light diffusing particle gradually decreases in the direction from the first end of the fourth subtype light diffusing particle to the second end of the fourth subtype light diffusing particle.

[0043] In some embodiments, the first cross-section of the fourth sub-type light diffusing particles may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a square, etc.

[0044] In some embodiments, the fourth sub-type light diffusing particles may be long tapered particles.

[0045] In some embodiments, when the fourth subtype light diffusing particles are long tapered particles, the first cross section of the fourth subtype light diffusing particles is circular or elliptical. Along the direction from the first end of the fourth subtype light diffusing particle to the second end of the fourth subtype light diffusing particle, the shape of the first cross section of the fourth subtype light diffusing particle is consistent and the area is reduced. When the first cross section of the fourth subtype light diffusing particle is elliptical, the ratio of the major axis of the ellipse to the minor axis of the ellipse of the first cross section of any of the fourth subtype light diffusing particles is greater than 1 and less than or equal to 3, such as 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, etc.

[0046] A first end of the fifth subtype light diffusing particle is connected to a second end of the fifth subtype light diffusing particle, and a diameter of a first circumscribing circle of the first cross section located at the first end of the fifth subtype light diffusing particle becomes smaller along a direction away from the second end of the fifth subtype light diffusing particle, and a diameter of a first circumscribing circle of the first cross section located at the second end of the fifth subtype light diffusing particle becomes smaller along a direction away from the first end of the fifth subtype light diffusing particle.

[0047] As can be understood, the diameter of the first circumscribing circle of the first cross section located at the first end of the fifth subtype light diffusing particle becomes smaller along the direction away from the second end of the fifth subtype light diffusing particle, the diameter of the first circumscribing circle of the first cross section located at the first end of the fifth subtype light diffusing particle tends to become smaller in the direction away from the second end of the fifth subtype light diffusing particle, including, but not limited to, the diameter of the first circumscribing circle of the first cross section located at the first end of the fifth subtype light diffusing particle gradually becoming smaller in the direction away from the second end of the fifth subtype light diffusing particle.

[0048] As can be understood, the diameter of the first circumscribing circle of the first cross section located at the second end of the fifth subtype light diffusing particle becomes smaller along the direction away from the first end of the fifth subtype light diffusing particle, the diameter of the first circumscribing circle of the first cross section located at the second end of the fifth subtype light diffusing particle tends to become smaller in the direction away from the first end of the fifth subtype light diffusing particle, and the diameter of the first circumscribing circle of the first cross section located at the second end of the fifth subtype light diffusing particle tends to become smaller in the direction away from the first end of the fifth subtype light diffusing particle, including, but not limited to, the diameter of the first circumscribing circle of the first cross section located at the second end of the fifth subtype light diffusing particle gradually becomes smaller in the direction away from the first end of the fifth subtype light diffusing particle.

[0049] In some embodiments, the first cross-section of the fifth sub-type light diffusing particles may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a square, etc.

[0050] In some embodiments, the fifth sub-type light diffusing particles may be double tapered particles and / or oval-spherical particles.

[0051] In some embodiments, when the fifth subtype light diffusing particles are double tapered particles and / or elliptical spherical particles, the first cross section of the fifth subtype light diffusing particles is circular or elliptical. Along the direction away from the second end of the fifth subtype light diffusing particles, the shape of the first cross section located at the first end of the fifth subtype light diffusing particles is consistent and the area is reduced, and along the direction away from the first end of the fifth subtype light diffusing particles, the shape of the first cross section located at the second end of the fifth subtype light diffusing particles is consistent and the area is reduced. When the first cross section of the fifth subtype light diffusing particles is elliptical, the ratio of the major axis of the ellipse to the minor axis of the ellipse of the first cross section of any of the fifth subtype light diffusing particles is greater than 1 and less than or equal to 3, and may be, for example, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, etc.

[0052] The difference between the fifth subtype light diffusing particle being a double tapered particle and the fifth subtype light diffusing particle being an ellipsoidal particle is that when the fifth subtype light diffusing particle is a double tapered particle, the cross section parallel to the major axis direction of the fifth subtype light diffusing particle is a polygon such as a triangle or a rectangle, and when the fifth subtype light diffusing particle is an ellipsoidal particle, the cross section parallel to the major axis direction of the fifth subtype light diffusing particle is an ellipse.

[0053] In some embodiments, the fifth subtype light diffusing particles can have more light propagation directions than the first subtype light diffusing particles, the second subtype light diffusing particles, the third subtype light diffusing particles, and the fourth subtype light diffusing particles, thereby improving the chromaticity viewing angle and contrast. Therefore, the first type light diffusing particles 1012a include at least the fifth subtype light diffusing particles. In the fifth subtype light diffusing particles, the change in the light propagation direction of ellipsoidal particles is better than that of double tapered particles, and preferably, the fifth subtype light diffusing particles include at least ellipsoidal particles.

[0054] In some embodiments, the first type light diffusion particles 1012a include the fifth subtype light diffusion particles, and the first subtype light diffusion particles further include at least one of the first subtype light diffusion particles, the second subtype light diffusion particles, the third subtype light diffusion particles, and the fourth subtype light diffusion particles. Preferably, the first subtype light diffusion particles include the first subtype light diffusion particles, the second subtype light diffusion particles, the third subtype light diffusion particles, the fourth subtype light diffusion particles, and the fifth subtype light diffusion particles, which increases the shape diversity of the light diffusion particles 1012, increases the optical anisotropy of the light diffusion particles 1012, and contributes to improving the enhancing effect on the contrast and brightness of the light diffusion particles 1012.

[0055] In some embodiments, the long axis length of the first type light diffusing particles 1012a is 4 microns or more, and the long axis length of the first type light diffusing particles 1012a is 30 micrometers or less, for example, 5 micrometers, 10 micrometers, 15 micrometers, 20 micrometers, 25 micrometers, etc., so that more light rays can change the propagation direction through the long axis surface of the first type light diffusing particles 1012a, thereby improving the enhancement effect of the light diffusing particles 1012 on contrast and brightness. Preferably, the long axis length of the first type light diffusing particles 1012a is 10 micrometers or more, and the long axis length of the first type light diffusing particles 1012a is 30 micrometers or less, which facilitates obtaining the first light diffusing particles 1012 with a suitable long axis length and more concentrated, and contributes to further improving the enhancement effect of the light diffusing particles 1012 on contrast and brightness.

[0056] In some embodiments, the light diffusing particles 1012 may consist of the first type light diffusing particles 1012a.

[0057] In some embodiments, in order to improve the chromaticity, viewing angle and contrast of the light diffusion film 101 while improving the haze improvement effect of the light diffusion film 101, the light diffusion particles 1012 further include a second type light diffusion particle 1012b.

[0058] Here, the second type light diffusing particle 1012b includes a plurality of second cross sections, each of the second cross sections includes one second circumscribing circle, the ratio of the long axis length of the second type light diffusing particle 1012b to the diameter of the second circumscribing circle having the largest diameter among the plurality of second circumscribing circles is 1 or more, the ratio of the long axis length of the second type light diffusing particle 1012b to the diameter of the second circumscribing circle having the largest diameter among the plurality of second circumscribing circles is less than 5, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.2, 2.5, 2.8, 3, 3.5, 4, 4.5, etc., and the second cross sections are perpendicular to the extension direction of the long axis of the second type light diffusing particle 1012b. The light diffusion particles 1012 include the second type light diffusion particles 1012b having a relatively small aspect ratio (the ratio of the major axis length to the diameter of the second circumscribed circle having the largest diameter), thereby improving the chromaticity viewing angle and contrast of the light diffusion film 101 and contributing to improving the haze improvement effect of the light diffusion film 101.

[0059] In some embodiments, the second type light diffusing particles 1012b are at least one selected from a sixth subtype light diffusing particle, a seventh subtype light diffusing particle, an eighth subtype light diffusing particle, a ninth subtype light diffusing particle, and a tenth subtype light diffusing particle, each having a different shape.

[0060] Here, the change value of the diameter of the second circumscribing circle of the second cross section of the sixth subtype light diffusing particle along the extension direction of the long axis of the sixth subtype light diffusing particle may be 0.3 micrometers or less, for example, 0 micrometers, 0.28 micrometers, 0.25 micrometers, 0.22 micrometers, 0.2 micrometers, 0.18 micrometers, 0.15 micrometers, 0.12 micrometers, 0.1 micrometers, 0.08 micrometers, 0.05 micrometers, 0.02 micrometers, etc. In some embodiments, along the extension direction of the long axis of the sixth subtype light diffusing particle, the diameter of the second circumscribing circle of the second cross section located at a first end of the sixth subtype light diffusing particle is the same as the diameter of the second circumscribing circle of the second cross section located at a middle part of the sixth subtype light diffusing particle, and the diameter of the second circumscribing circle of the second cross section located at a second end of the sixth subtype light diffusing particle is the same as the diameter of the second circumscribing circle of the second cross section located at a middle part of the sixth subtype light diffusing particle.

[0061] In some embodiments, the second cross-section of the sixth sub-type light diffusing particles may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a rectangle, etc.

[0062] In some embodiments, the sixth sub-type light diffusing particles are cuboid particles or rectangular particles, the second cross-section of the sixth sub-type light diffusing particles is square or rectangular, and the diameter of a second circumscribing circle of the second cross-section of any of the sixth sub-type light diffusing particles is the diagonal length of the square or rectangle that the second cross-section represents.

[0063] The sixth subtype light diffusing particles are similar to the first subtype light diffusing particles, but the difference is that the ratio of the long axis length of the sixth subtype light diffusing particle to the diameter of the second circumscribing circle having the largest diameter among the second circumscribing circles of the multiple second cross sections of the sixth subtype light diffusing particle is preferably close to 1, and may be, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.2, 2.5, 3, etc.

[0064] A first end of the seventh subtype light diffusing particle is connected to a second end of the seventh subtype light diffusing particle, and a diameter of a second circumscribing circle of the second cross section located at the first end of the seventh subtype light diffusing particle becomes smaller along a direction away from the second end of the seventh subtype light diffusing particle, and a diameter of a second circumscribing circle of the second cross section located at the second end of the seventh subtype light diffusing particle becomes smaller along a direction away from the first end of the seventh subtype light diffusing particle.

[0065] As can be understood, the diameter of the second circumscribing circle of the second cross section located at the first end of the 7th subtype light diffusing particle becomes smaller along the direction away from the second end of the 7th subtype light diffusing particle, the diameter of the second circumscribing circle of the second cross section located at the first end of the 7th subtype light diffusing particle tends to become smaller in the direction away from the second end of the 7th subtype light diffusing particle, and the diameter of the second circumscribing circle of the second cross section located at the first end of the 7th subtype light diffusing particle tends to become smaller in the direction away from the second end of the 7th subtype light diffusing particle, including, but not limited to, the diameter of the second circumscribing circle of the second cross section located at the first end of the 7th subtype light diffusing particle gradually becomes smaller in the direction away from the second end of the 7th subtype light diffusing particle.

[0066] As can be understood, the diameter of the second circumscribing circle of the second cross section located at the second end of the 7th subtype light diffusing particle becomes smaller along the direction away from the first end of the 7th subtype light diffusing particle, the diameter of the second circumscribing circle of the second cross section located at the second end of the 7th subtype light diffusing particle tends to become smaller in the direction away from the first end of the 7th subtype light diffusing particle, including, but not limited to, the diameter of the second circumscribing circle of the second cross section located at the second end of the 7th subtype light diffusing particle gradually becoming smaller in the direction away from the first end of the 7th subtype light diffusing particle.

[0067] In some embodiments, the second cross-section of the seventh sub-type light diffusing particles may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a rectangle, etc.

[0068] In some embodiments, when the seventh subtype light diffusing particles are spherical or ellipsoidal particles, the second cross section of the seventh subtype light diffusing particles is circular or elliptical. When the second cross section of the seventh subtype light diffusing particles is elliptical, the ratio of the major axis of the ellipse of the second cross section of any of the seventh subtype light diffusing particles to the minor axis of the ellipse is greater than 1 and not greater than 3, for example, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, etc. When the seventh subtype light diffusing particles are spherical, the second cross section of any of the seventh subtype light diffusing particles is circular, and the second circumscribing circle of the second cross section of any of the seventh subtype light diffusing particles overlaps with the second cross section, and the ratio of the major axis length of the seventh subtype light diffusing particle to the diameter of the second circumscribing circle with the largest diameter among the plurality of second cross sections of the seventh subtype light diffusing particles is 1.

[0069] The seventh subtype light diffusing particles are similar to the fifth subtype light diffusing particles, but differ in that the ratio of the major axis length of the seventh subtype light diffusing particle to the diameter of the second circumscribing circle having the largest diameter among the plurality of second circumscribing circles of the seventh subtype light diffusing particle is smaller than the ratio of the major axis length of the fifth subtype light diffusing particle to the diameter of the first circumscribing circle having the largest diameter among the plurality of first circumscribing circles of the fifth subtype light diffusing particle. When the seventh subtype light diffusing particles are ellipsoidal spherical particles, it is more preferable that the shape of the seventh subtype light diffusing particles is similar to that of spherical particles, i.e., the closer the major axis length of the seventh subtype light diffusing particle to the diameter of the seventh subtype light diffusing particle, the better. Preferably, the ratio of the major axis length of the 7th subtype light diffusing particle to the diameter of the second circumscribing circle having the largest diameter among the plurality of second circumscribing circles of the 7th subtype light diffusing particle is 1 or more, and the ratio of the major axis length of the 7th subtype light diffusing particle to the diameter of the second circumscribing circle having the largest diameter among the plurality of second circumscribing circles of the 7th subtype light diffusing particle is not more than 3. More preferably, the ratio of the major axis length of the 7th subtype light diffusing particle to the diameter of the second circumscribing circle having the largest diameter among the plurality of second circumscribing circles of the 7th subtype light diffusing particle is 1 or more, and the ratio of the major axis length of the 7th subtype light diffusing particle to the diameter of the second circumscribing circle having the largest diameter among the plurality of second circumscribing circles of the 7th subtype light diffusing particle is 1.5 or less.

[0070] The change in diameter of the second circumscribing circle of the second cross section located at the middle of the eighth subtype light diffusing particle along the extension direction of the long axis of the eighth subtype light diffusing particle is 1 micrometer or less, for example, 0 micrometers, 0.95 micrometers, 0.8 micrometers, 0.78 micrometers, 0.75 micrometers, 0.72 micrometers, 0.7 micrometers, 0.68 micrometers, 0.65 micrometers, 0.62 micrometers, 0.6 micrometers, 0.58 micrometers, 0.55 micrometers, 0.52 micrometers. , 0.5 micrometers, 0.48 micrometers, 0.45 micrometers, 0.42 micrometers, 0.4 micrometers, 0.38 micrometers, 0.35 micrometers, 0.32 micrometers, 0.3 micrometers, 0.28 micrometers, 0.25 micrometers, 0.22 micrometers, 0.2 micrometers, 0.18 micrometers, 0.15 micrometers, 0.12 micrometers, 0.1 micrometers, 0.08 micrometers, 0.05 micrometers, 0.02 micrometers, and the like.Along a direction away from the intermediate portion of the eighth subtype light diffusing particle, a diameter of a second circumscribing circle of the second cross section located at a first end of the eighth subtype light diffusing particle becomes smaller, and a change value of the diameter of the second end of the eighth subtype light diffusing particle is 1 micrometer or less, for example, 0 micrometer, 0.95 micrometer, 0.8 micrometer, 0.78 micrometer, 0.75 micrometer, 0.72 micrometer, 0.7 micrometer, 0.68 micrometer, 0.65 micrometer, 0.62 micrometer, 0.6 micrometer, 0.58 micrometer, 0.55 micrometer. meter, 0.52 micrometer, 0.5 micrometer, 0.48 micrometer, 0.45 micrometer, 0.42 micrometer, 0.4 micrometer, 0.38 micrometer, 0.35 micrometer, 0.32 micrometer, 0.3 micrometer, 0.28 micrometer, 0.25 micrometer, 0.22 micrometer, 0.2 micrometer, 0.18 micrometer, 0.15 micrometer, 0.12 micrometer, 0.1 micrometer, 0.08 micrometer, 0.05 micrometer, 0.02 micrometer, etc. In some embodiments, along a direction away from a middle portion of the 8th subtype light diffusing particle, a diameter of a second circumscribing circle of the second cross section located at a first end of the 8th subtype light diffusing particle becomes smaller, and a diameter of a second circumscribing circle of the second cross section located at a second end of the 8th subtype light diffusing particle is the same as a diameter of a second circumscribing circle of the second cross section located at a middle portion of the 8th subtype light diffusing particle.

[0071] As can be understood, the diameter of the second circumscribing circle of the second cross section located at the first end of the 8th subtype light diffusing particle tends to become smaller along the direction away from the intermediate portion of the 8th subtype light diffusing particle, and the diameter of the second circumscribing circle of the second cross section located at the first end of the 8th subtype light diffusing particle tends to become smaller in the direction away from the intermediate portion of the 8th subtype light diffusing particle, including, but not limited to, the diameter of the second circumscribing circle of the second cross section located at the first end of the 8th subtype light diffusing particle gradually becomes smaller in the direction away from the intermediate portion of the 8th subtype light diffusing particle.

[0072] In some embodiments, the second cross-section of the eighth sub-type light diffusing particle may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a square, etc.

[0073] In some embodiments, the eighth sub-type light diffusing particles may be needle-shaped particles with a smaller diameter at one end.

[0074] In some embodiments, when the 8th subtype light diffusing particle is a needle-like particle with a smaller diameter at one end, the second cross section of the 8th subtype light diffusing particle may be circular or elliptical. When the second cross section located at the second end of the 8th subtype light diffusing particle or the second cross section located at the middle part of the 8th subtype light diffusing particle is elliptical, the ratio of the major axis of the ellipse of the second cross section located at either the second end or the middle part of the 8th subtype light diffusing particle to the minor axis of the ellipse is greater than 1 and less than or equal to 3, for example, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, etc. The shape of the second cross section located at the first end of the 8th subtype light diffusing particle is the same as the shape of the second cross section located at the middle part of the 8th subtype light diffusing particle, and the area decreases along the direction away from the middle part of the 8th subtype light diffusing particle.

[0075] The change in diameter of the second circumscribing circle of the second cross section located at the middle of the 9th subtype light diffusing particle along the extension direction of the long axis of the 9th subtype light diffusing particle is 1 micrometer or less, for example, 0 micrometers, 0.95 micrometers, 0.8 micrometers, 0.78 micrometers, 0.75 micrometers, 0.72 micrometers, 0.7 micrometers, 0.68 micrometers, 0.65 micrometers, 0.62 micrometers, 0.6 micrometers, 0.58 micrometers, 0.55 micrometers, 0.52 micrometers. , 0.5 micrometers, 0.48 micrometers, 0.45 micrometers, 0.42 micrometers, 0.4 micrometers, 0.38 micrometers, 0.35 micrometers, 0.32 micrometers, 0.3 micrometers, 0.28 micrometers, 0.25 micrometers, 0.22 micrometers, 0.2 micrometers, 0.18 micrometers, 0.15 micrometers, 0.12 micrometers, 0.1 micrometers, 0.08 micrometers, 0.05 micrometers, 0.02 micrometers, etc. Along a direction away from the intermediate portion of the 9th subtype light diffusing particle, a diameter of a second circumscribing circle of the second cross section located at a first end of the 9th subtype light diffusing particle becomes smaller, and a diameter of a second circumscribing circle of the second cross section located at a second end of the 9th subtype light diffusing particle becomes smaller. In some embodiments, along the extension direction of the long axis of the 9th subtype light diffusing particle, the diameter of the second circumscribing circle of the second cross section located at the middle part of the 9th subtype light diffusing particle is uniform, and the diameters of the second circumscribing circle of the second cross section located at the first end of the 9th subtype light diffusing particle and located at the second end of the 9th subtype light diffusing particle vary.

[0076] As can be understood, the diameter of the second circumscribing circle of the second cross section located at the first end of the 9th subtype light diffusing particle tends to become smaller along the direction away from the intermediate portion of the 9th subtype light diffusing particle, and the diameter of the second circumscribing circle of the second cross section located at the first end of the 9th subtype light diffusing particle tends to become smaller in the direction away from the intermediate portion of the 9th subtype light diffusing particle, including, but not limited to, the diameter of the second circumscribing circle of the second cross section located at the first end of the 9th subtype light diffusing particle gradually becomes smaller in the direction away from the intermediate portion of the 9th subtype light diffusing particle.

[0077] As can be understood, the diameter of the second circumscribing circle of the second cross section located at the second end of the 9th subtype light diffusing particle becomes smaller along the direction away from the intermediate portion of the 9th subtype light diffusing particle, and the diameter of the second circumscribing circle of the second cross section located at the second end of the 9th subtype light diffusing particle tends to become smaller in the direction away from the intermediate portion of the 9th subtype light diffusing particle, including, but not limited to, the diameter of the second circumscribing circle of the second cross section located at the second end of the 9th subtype light diffusing particle gradually becomes smaller in the direction away from the intermediate portion of the 9th subtype light diffusing particle.

[0078] In some embodiments, the second cross-section of the ninth sub-type light diffusing particles may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a rectangle, etc.

[0079] In some embodiments, the ninth sub-type light diffusing particles may be needle-shaped particles with decreasing diameters at both ends.

[0080] In some embodiments, when the 9th subtype light diffusing particle is a needle-like particle with a smaller diameter at both ends, the shape of the second cross section of the 9th subtype light diffusing particle may be circular or elliptical. When the second cross section located at the middle part of the 9th subtype light diffusing particle is elliptical, the ratio of the major axis of the ellipse of the second cross section located at any part of the 9th subtype middle part to the minor axis of the ellipse is greater than 1 and less than or equal to 3, for example, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, etc. The shape of the second cross section located at the first end of the 9th subtype light diffusing particle and at the second end of the 9th subtype light diffusing particle is consistent with the shape of the second cross section located at the middle part of the 9th subtype light diffusing particle, and the area decreases along the direction away from the middle part of the 9th subtype light diffusing particle.

[0081] A first end of the 10th sub-type light diffusing particle is connected to a second end of the 10th sub-type light diffusing particle, and a diameter of a second circumscribing circle of the second cross section of the 10th sub-type light diffusing particle becomes smaller along a direction from the first end of the 10th sub-type light diffusing particle to the second end of the 10th sub-type light diffusing particle.

[0082] As can be understood, the diameter of the second circumscribing circle of the second cross section of the 10 subtype light diffusing particle becomes smaller along the direction from the first end of the 10 subtype light diffusing particle to the second end of the 10 subtype light diffusing particle, and the diameter of the second circumscribing circle of the second cross section of the 10 subtype light diffusing particle tends to become smaller in the direction from the first end of the 10 subtype light diffusing particle to the second end of the 10 subtype light diffusing particle, including, but not limited to, the diameter of the second circumscribing circle of the second cross section of the 10 subtype light diffusing particle gradually becomes smaller in the direction from the first end of the 10 subtype light diffusing particle to the second end of the 10 subtype light diffusing particle.

[0083] In some embodiments, the second cross-section of the tenth sub-type light diffusing particle may be a regular or irregular shape, such as a circle, an ellipse, a triangle, a square, etc.

[0084] In some embodiments, the tenth sub-type light diffusing particles may be long tapered particles.

[0085] In some embodiments, when the 10th subtype light diffusing particle is a long tapered particle, the second cross section of the 10th subtype light diffusing particle is circular or elliptical. Along the direction from the first end of the 10th subtype light diffusing particle to the second end of the 10th subtype light diffusing particle, the shape of the second cross section of the 10th subtype light diffusing particle is consistent and the area is reduced. When the 10th subtype light diffusing particle has a second cross section of an ellipse, the ratio of the major axis of the ellipse to the minor axis of the ellipse of any of the 10th subtype light diffusing particles is greater than 1 and less than or equal to 3, such as 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, etc.

[0086] In some embodiments, in order to facilitate the light diffusion effect, the long axis length of the second type light diffusion particles 1012b is 12 nanometers or more, and the long axis length of the second type light diffusion particles 1012b is 12.4 micrometers or less, such as 20 nanometers, 50 nanometers, 100 nanometers, 500 nanometers, 1 micrometer, 3 micrometers, 5 micrometers, 8 micrometers, 10 micrometers, etc. Preferably, the long axis length of the second type light diffusion particles 1012b is 1 micrometer or more, and the long axis length of the second type diffusion particles 1012b is 5 micrometers or less. More preferably, the long axis length of the second type light diffusion particles 1012b is 1.5 micrometers or more, and the long axis length of the seventh subtype diffusion particles is 4 micrometers or less.

[0087] The second type light diffusing particles 1012b have a slightly weaker effect of improving chromaticity viewing angle and contrast compared to the first type light diffusing particles 1012a, and the relatively small amount of the second type light diffusing particles 1012b can have a significant effect of adjusting the haze of the light diffusing film 101. Therefore, the mass fraction of the second type light diffusing particles 1012b in the light diffusing particles 1012 may be equal to or less than the mass fraction of the first type light diffusing particles 1012a in the light diffusing particles 1012. For example, the mass fraction of the first type light diffusing particles 1012a in the light diffusing particles 1012 is 50% or more, and the mass fraction of the second type light diffusing particles 1012b in the light diffusing particles 1012 is 50% or less. The mass fraction of the first type light diffusing particles 1012a in the light diffusing particles 1012 may be 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 99%, and so on.

[0088] In some embodiments, when the light diffusing particles 1012 include the second type light diffusing particles 1012b, and the second type light diffusing particles 1012b include the sixth subtype light diffusing particles and the seventh subtype light diffusing particles, the mass fraction of the sixth subtype light diffusing particles in the light diffusing particles 1012 is smaller than the mass fraction of the seventh subtype light diffusing particles in the light diffusing particles 1012.

[0089] In some embodiments, the first type light diffusing particles 1012a include at least the fifth subtype light diffusing particles, and the mass fraction of the fifth subtype light diffusing particles in the light diffusing particles 1012 is 20% or more, and the mass fraction of the fifth subtype light diffusing particles in the light diffusing particles 1012 is 100% or less. Preferably, the mass fraction of the fifth subtype light diffusing particles in the light diffusing particles 1012 is 55% or more, and the mass fraction of the fifth subtype light diffusing particles in the light diffusing particles 1012 is 100% or less, for example, 60%, 65%, 70%, 80%, 85%, 90%, 95%, etc. When the first type light diffusing particles 1012a further include the first subtype light diffusing particles, the second subtype light diffusing particles, the third subtype light diffusing particles, and the fourth subtype light diffusing particles, and the second type light diffusing particles 1012b further include the sixth subtype light diffusing particles and / or the seventh subtype light diffusing particles, the total mass fraction of the first subtype light diffusing particles, the second subtype light diffusing particles, the third subtype light diffusing particles, the fourth subtype light diffusing particles, and the second type light diffusing particles 1012b in the light diffusing particles 1012 is 80% or more and less than 100%. Preferably, the sum of the mass fractions of the first subtype light diffusing particles, the second subtype light diffusing particles, the third subtype light diffusing particles, the fourth subtype light diffusing particles, and the second type light diffusing particles 1012b in the light diffusing particles 1012 is greater than 0% and less than 45%, and may be, for example, 40, 35%, 30%, 25%, 20%, 15%, 10%, 5%, etc.

[0090] In some embodiments, the mass fraction of the light diffusion particles 1012 in the light diffusion film 101 is less than 3%, for example, 0.0001%, 0.001%, 0.01%, 0.02%, 0.05%, 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, etc., in order to be uniformly dispersed in the light diffusion film 101, the light diffusion particles 1012 can improve the viewing angle of the polarizer by utilizing the light refraction effect of the light diffusion particles 1012, avoid the reduction of the emitted light caused by providing an additional film layer on the polarizer, and further improve the chromaticity viewing angle and contrast of the display device having the light diffusion film 101, and can also improve the light output rate of the display device. The light diffusion particles 1012 have a relatively small mass fraction in the light diffusion film 101, so that the contrast and chromaticity viewing angle can be effectively improved. Preferably, the mass fraction of the light diffusion particles 1012 in the light diffusion film 101 is 0.001% or more, and the mass fraction of the light diffusion particles 1012 in the light diffusion film 101 is less than 3%. More preferably, the mass fraction of the light diffusion particles 1012 in the light diffusion film 101 is 0.1% or more, and the mass fraction of the light diffusion particles 1012 in the light diffusion film 101 is 1% or less. Even more preferably, the mass fraction of the light diffusion particles 1012 in the light diffusion film 101 is 0.1% or more, and the mass fraction of the light diffusion particles 1012 in the light diffusion film 101 is 0.5% or less.

[0091] In some embodiments, the particle size distribution of the light diffusion particles 1012 may be polydisperse or monodisperse. Preferably, the particle size distribution of the light diffusion particles 1012 is monodisperse, and the light diffusion particles 1012 contribute to comprehensively improving the optical performance of the optical film. When the particle size distribution of the light diffusion particles 1012 is monodisperse, the light diffusion particles 1012 have an average particle size, and the average particle size of the light diffusion particles 1012 is the average value of the major axis length of the light diffusion particles 1012, and when the light diffusion particles 1012 include spherical particles and / or cubic particles, the particle size of the spherical particles is its diameter, and the particle size of the cubic particles is its side length. When the particle size distribution of the light diffusion particles 1012 is monodisperse, the long axis length of any of the light diffusion particles is 20% or more of the average particle size of the light diffusion particles, and the long axis length of any of the light diffusion particles is 180% or less of the average particle size of the light diffusion particles, i.e., 20% × average particle size of the light diffusion particles 1012 ≦ long axis length of any of the light diffusion particles 1012 ≦ 180% × average particle size of the light diffusion particles 1012. Preferably, when the particle size distribution of the light diffusing particles 1012 is monodisperse, the long axis length of any of the light diffusing particles 1012 is 50% or more of the average particle size of the light diffusing particles 1012, and the long axis length of any of the light diffusing particles 1012 is 150% or less of the average particle size of the light diffusing particles 1012, i.e., 50% × average particle size of the light diffusing particles 1012 ≦ long axis length of any of the light diffusing particles 1012 ≦ 150% × average particle size of the light diffusing particles 1012.

[0092] In some embodiments, the second type light diffusing particles 1012b are whiskers. The material of the first type light diffusing particles 1012a and the material of the second type light diffusing particles 1012b are at least one selected from the group consisting of organic materials, inorganic materials, and composite materials. For example, the material of the first type light diffusing particles 1012a and the material of the second type light diffusing particles 1012b are at least one selected from the group consisting of polysiloxane, polymethylmethacrylate, polystyrene, silica, titanium dioxide, zirconium dioxide, silicon carbide, silicon nitride, zinc oxide, magnesium oxide, aluminum oxide, calcium sulfate, calcium carbonate, potassium titanate, and aluminum borate.

[0093] In some embodiments, the second type light diffusing particles 1012b and / or the first type light diffusing particles 1012a may be surface-modified to improve the dispersibility of the second type light diffusing particles 1012b and / or the first type light diffusing particles 1012a in the substrate 1011 or to improve the functionality of the second type light diffusing particles 1012b and / or the first type light diffusing particles 1012a, such as toughness. When the second type light diffusing particles 1012b and / or the first type light diffusing particles 1012a are surface-modified, the surface of the second type light diffusing particles 1012b and / or the first type light diffusing particles 1012a is modified by at least one of inorganic cations, inorganic anions, polymers, coupling agents, or surfactants. That is, the surface of the second type light diffusing particles 1012b and / or the first type light diffusing particles 1012a includes at least one of inorganic cation groups, inorganic anion groups, polymer groups, coupling agent groups, or surfactant groups.

[0094] Specifically, the surface of the second type light diffusing particle 1012b and / or the first type light diffusing particle 1012a is modified with at least one selected from magnesium chloride, calcium chloride, barium chloride, strontium chloride, stearic acid, sodium stearate, zinc octadecanoate, sulfonic acid surfactant, thio surfactant, titanate ester, aluminum acid ester, polyacrylamide, silane, alkyl phosphate ester, aryl phosphate ester, alkyl phosphate, aryl phosphate, alkyl alcohol amide phosphate ester, imidazoline phosphate ester, imidazoline phosphate, high polyphosphate ester, high polyphosphate, and silicone phosphate ester. Preferably, the surface of the second type light diffusing particle 1012b and / or the first type light diffusing particle 1012a is modified with at least one of sulfonic acid surfactant and thio surfactant. The sulfonic acid surfactant is at least one selected from alkyl sulfonates and fluoroalkyl sulfonates, specifically, for example, at least one selected from sodium dodecyl sulfonate, sodium dodecylbenzene sulfonate, and sodium fluorododecyl sulfonate. The thio surfactant is at least one selected from thiols and fluorothiols, specifically, for example, at least one selected from octylthiol, dodecylthiol, tetradecylthiol, octadecylthiol, fluorooctylthiol, and fluorododecylthiol. After the sulfonic acid surfactant is mixed with the surface-modified light-diffusing particles 1012, the sulfonic acid surfactant groups form a sulfonic acid group shell layer, such as a benzene ring sulfonic acid group shell layer, on the surface of the whiskers to protect the light-diffusing particles 1012, improve the toughness of the light-diffusing particles 1012, and contribute to reducing breakage of the second type light-diffusing particles 1012b and / or the first type light-diffusing particles 1012a in the light-diffusing film 101.After the thio surfactant group is mixed with the surface-modified light-diffusing particles 1012, the thio surfactant group and the hydroxyl group on the surface of the whiskers form a cross-linked network of OSO, and the binding energy of OSO is relatively large, which protects the second type light-diffusing particles 1012b and / or the first type light-diffusing particles 1012a during the process of mixing the second type light-diffusing particles 1012b and / or the first type light-diffusing particles 1012a with the material of the substrate 1011 to form the light-diffusing film 101, reduces the breakage of the second type light-diffusing particles 1012b and / or the first type light-diffusing particles 1012a, and contributes to enhancing the improvement effect of the second type light-diffusing particles 1012b and / or the first type light-diffusing particles 1012a on optical functions such as contrast and brightness. More preferably, the second type light diffusing particles 1012b and / or the first type light diffusing particles 1012a are at least one of a fluorine-substituted sulfonic acid surfactant and a fluorine-substituted thio surfactant, specifically, for example, at least one of sodium fluorododecylsulfonate, fluorooctylthiol, and fluorodothiol, which provides fluorine atoms with high stability in alkyl chains, the bond energy of a carbon-fluorine bond is higher than the bond energy of a carbon-carbon bond, and the carbon-fluorine bond has a shielding effect on the carbon-carbon bond, contributing to the protection of the carbon-carbon bond, thereby improving the stability of the second type light diffusing particles 1012b and / or the first type light diffusing particles 1012a.

[0095] In some embodiments, the substrate 1011 is at least one selected from the following: modified or unmodified polyester, modified or unmodified acetate cellulose.

[0096] In some embodiments, the modified or unmodified polyester can include at least one of modified or unmodified polyethylene terephthalate, modified or unmodified polycarbonate, modified or unmodified polymethyl methacrylate, modified or unmodified polyethylene naphthalate. The modified or unmodified acetate cellulose can include modified or unmodified triacetate cellulose.

[0097] In some embodiments, the substrate 1011 may include a first sub-substrate and / or a second sub-substrate, the first sub-substrate being at least one selected from unmodified polyester and unmodified acetate cellulose, and the second sub-substrate being at least one selected from modified polyester and modified acetate cellulose. In the substrate 1011, the mass fraction of the first sub-substrate is greater than the mass fraction of the second sub-substrate.

[0098] In some embodiments, the first sub-substrate and the second sub-substrate are uniformly mixed with each other, and the mass fraction of the first sub-substrate in the substrate 1011 is 65% or more, for example, 70%, 75%, 80%, 85%, 90%, 95%, 99%, etc. The mass fraction of the second sub-substrate in the substrate 1011 is 35% or more, for example, 1%, 5%, 10%, 15%, 20%, 25%, 30%, etc. The mutual solubility of a polyester that is favorable for modification, such as polyethylene terephthalate, and an unmodified polyester, such as polyethylene terephthalate, is good, or the mutual solubility of an unmodified acetate cellulose, such as triacetate cellulose, and an unmodified acetate cellulose, such as triacetate cellulose, is good, which improves the mechanical properties, flatness, and crystallinity of the substrate 1011 and improves the dispersibility of the light diffusion particles 1012, thereby contributing to improving the optical performance of the light diffusion film 101.

[0099] In some embodiments, modified triacetate cellulose, modified polyethylene terephthalate, modified polycarbonate, modified polymethacrylate, or modified polyethylene naphthalate can be obtained by hydrophilically or lipophilically modifying unmodified triacetate fiber, unmodified polyethylene terephthalate, unmodified polycarbonate, unmodified polymethacrylate, or unmodified polyethylene naphthalate, respectively. For example, modified polyethylene terephthalate can be obtained by introducing a linear alkyl side chain, a carboxyl side chain, a hydroxyl side chain, or a fluorine-containing group side chain into unmodified polyethylene terephthalate. When modified polyethylene terephthalate is obtained by introducing a carboxyl side chain and / or a hydroxyl side chain into unmodified polyethylene terephthalate, modified polyethylene terephthalate is obtained by introducing a carboxyl side chain and / or a hydroxyl side chain into the phenyl group of unmodified polyethylene terephthalate. TIFF2025048731000002.tif1257 groups can be introduced, where n and m are both integers of 0 or more and 10 or less.

[0100] In some embodiments, when the first sub-substrate is selected from unmodified polyethylene terephthalate, the second sub-substrate is selected from modified polyethylene terephthalate, and the mass fraction of the second sub-substrate in the substrate 1011 is 35% or less. The mutual solubility of polyethylene terephthalate, which is advantageous for modification, and unmodified polyethylene terephthalate is good, which improves the mechanical properties, flatness, and crystallinity of the substrate 1011 and improves the dispersibility of the light diffusion particles 1012, thereby contributing to improving the optical performance of the light diffusion film 101.

[0101] In some embodiments, the difference in refractive index between the substrate 1011 and the light diffusing particles 1012 is greater than or equal to 0.02, such as 0.03, 0.05, 0.09, 0.1, 0.15, 0.2, etc., so as to realize the light diffusing function of the light diffusing particles 1012. Preferably, the difference in refractive index between the substrate 1011 and the light diffusing particles 1012 is greater than or equal to 0.1, such as 0.12, 0.13, 0.14, 0.15, 0.2, etc.

[0102] In some embodiments, the material of the first type light diffusing particles 1012a and the material of the second type light diffusing particles 1012b may be the same or different in the light diffusing particles 1012 in the same light diffusing film 101. Therefore, the refractive index difference between the first type light diffusing particles 1012a and the substrate 1011 may be the same or different from the refractive index difference between the second type light diffusing particles 1012b and the substrate 1011.

[0103] In some embodiments, the refractive index of the first type light diffusing particles 1012a is greater than the refractive index of the substrate 1011. The refractive index of the second type light diffusing particles 1012b is greater than the refractive index of the substrate 1011. The refractive index of the second type light diffusing particles 1012b is greater than the refractive index of the first type light diffusing particles 1012a.

[0104] In some embodiments, the substrate 1011 has a glass transition temperature between 70°C and 600°C, such as 80°C, 90°C, 100°C, 150°C, 200°C, 250°C, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, etc.

[0105] In some embodiments, the substrate 1011 has a modulus of elasticity of 500 to 5000 megapascals at 23° C., for example, 600 megapascal, 700 megapascal, 800 megapascal, 900 megapascal, 1000 megapascal, 1200 megapascal, 1500 megapascal, 1800 megapascal, 2000 megapascal, 2200 megapascal, 2500 megapascal, 2800 megapascal, 3000 megapascal, 3200 megapascal, 3500 megapascal, 3800 megapascal, 4000 megapascal, 4200 megapascal, 4500 megapascal, 4800 megapascal, etc.

[0106] In some embodiments, the elastic modulus of the substrate 1011 is obtainable at a humidity of 50%.

[0107] In some embodiments, in order to facilitate processing of the light diffusion film 101 and maintain suitable light transmittance of the light diffusion film 101, the thickness of the light diffusion film 101 is 5 micrometers or more, and the thickness of the light diffusion film 101 is 500 micrometers or less, for example, 10 micrometers, 50 micrometers, 60 micrometers, 100 micrometers, 150 micrometers, 200 micrometers, 250 micrometers, 300 micrometers, 350 micrometers, 400 micrometers, 450 micrometers, etc. Preferably, the thickness of the light diffusion film 101 is 15 micrometers or more, and the thickness of the light diffusion film 101 is 150 micrometers or less, for example, 20 micrometers, 25 micrometers, 30 micrometers, 40 micrometers, 50 micrometers, 60 micrometers, 80 micrometers, 100 micrometers, 120 micrometers, 130 micrometers, 140 micrometers, etc.

[0108] The light diffusion film 101 provided in the embodiment of the present invention improves the viewing angle of the polarizing plate by utilizing the refraction effect of the light diffusion particles 1012 on the light by adding light diffusion particles 1012 having a mass fraction of less than 3% to the substrate 1011 of the light diffusion film 101, and avoids the reduction in the emitted light caused by adding an additional film layer to the polarizing plate, and further improves the chromaticity viewing angle and contrast of a display device having the light diffusion film 101, as well as improving the light output rate of the display device.

[0109] 3 to 6, the embodiment of the present invention further provides a polarizer 100, which includes a light diffusing film 101. As shown in FIG.

[0110] The polarizing plate 100 further includes a polarizing layer 102 disposed on one side of the light diffusing film 101 .

[0111] 3 to 6, in some embodiments, the polarizer 100 further includes a second optical functional layer 103 located on at least one side of the substrate 1011.

[0112] Here, the second optical functional layer 103 is located between the polarizing layer 102 and the light diffusion film 101, or the second optical functional layer 103 is located on the side of the light diffusion film 101 away from the polarizing layer 102.

[0113] In some embodiments, the second optical functional layer 103 is located on the side of the light diffusion film 101 away from the polarizing layer 102, and the polarizing plate 100 further includes a first adhesive layer 104 located on the side of the light diffusion film 101 closer to the polarizing layer 102.

[0114] Here, the first adhesive layer 104 is in direct contact with the polarizing layer 102, or the polarizing plate 100 further includes a protective layer 105 positioned between the light diffusion film 101 and the polarizing layer 102, and the first adhesive layer 104 is in direct contact with the protective layer 105.

[0115] In some embodiments, the first adhesive layer 104 is in direct contact with the light diffusion film 101, and the first adhesive layer 104 is in direct contact with the polarizing layer 102, or the first adhesive layer 104 is in direct contact with the light diffusion film 101 and the first adhesive layer 104 is in direct contact with the protective layer 105.

[0116] In some embodiments, the first adhesive layer 104 is at least one selected from the group consisting of water gum, pressure sensitive adhesive, and UV adhesive, where the water gum material can be selected from polyvinyl alcohol, the pressure sensitive adhesive material can be selected from acrylic ester copolymers, and the UV adhesive material can be selected from multifunctional acrylic ester monomers.

[0117] 3 to 5, in some embodiments, the second optical functional layer 103 includes at least one of a transparent hardening sub-layer 107, a low-reflection sub-layer 108, an anti-reflection sub-layer, an anti-fingerprint sub-layer, and an anti-static layer. When the second optical functional layer 103 is a low-reflection sub-layer 108, the low-reflection sub-layer 108 can be formed by laminating a transparent hardening sub-portion 108a and a low-refractive sub-portion 108b.

[0118] In some embodiments, the polarizing layer 102 is made of polyvinyl alcohol and a dye.

[0119] In some embodiments, the polarizing plate 100 further includes a release layer 109 located on the side of the polarizing layer 102 away from the light diffusion film 101, and the release layer 109 and the polarizing layer 102 are adhered to each other via a second adhesive layer 110. When the polarizing plate 100 is applied to a display device, the release layer 109 is removed to expose the second adhesive layer 110, and the polarizing plate 100 is attached to a display panel via the second adhesive layer 110.

[0120] In some embodiments, the polarizer 100 further includes a compensation layer 111 located between the second adhesive layer 110 and the polarizing layer 102 .

[0121] In the embodiment of the present invention, by providing a light diffusing film 101, optical defects such as moire and white spots caused by the polarizing plate 100 are avoided, and the chromaticity viewing angle and contrast are improved when a display device having the polarizing plate 100 is used.

[0122] Referring to FIG. 7, an embodiment of the present invention further provides a display device 10 , which includes the polarizer 100 .

[0123] Specifically, the display device includes a display panel 200 and a first polarizer 300, the first polarizer 300 being located on the light-emitting side of the display panel 200, and the first polarizer 300 being selected from the polarizers 100 described above.

[0124] In some embodiments, the display panel 200 may be a liquid crystal display panel, a self-luminous display panel, etc., and the self-luminous display panel may be an OLED (Organic Light-Emitting Diode) display panel, etc.

[0125] In some embodiments, the light diffusing film 101 of the first polarizer 300 is located on the side of the polarizing layer 102 of the first polarizer 300 that is away from the display panel 200 .

[0126] When the display panel 200 is a liquid crystal display panel, the display device 10 further includes a backlight module 400 located on a side of the display panel 200 farther from the first polarizer 300, the backlight module 400 being used to provide a light source to the display panel 200, and the display device 10 further includes a second polarizer 500 located between the backlight module 400 and the display panel 200. The second polarizer 500 may be selected from the polarizer 100, or the second polarizer 500 may not be selected from the polarizer 100.

[0127] The present invention will now be described in more detail with reference to some examples. However, it should be noted that these examples are provided for illustrative purposes only and should not be understood as limiting the present invention in any way. EXAMPLES

[0128] In this embodiment, the material of the substrate was unmodified polyethylene terephthalate, and the light-diffusing particles in the substrate were a mixture of spherical silica and rod-shaped silica in a mass ratio of 1:1 to form the light-diffusing film 1, and the mass fraction of the light-diffusing particles in the light-diffusing film 1 was 0.1%. EXAMPLES

[0129] This embodiment is the same as or similar to Example 1, with the difference being that the light-diffusing particles in the substrate are a mixture of elliptical spherical silica and rod-shaped silica in a mass ratio of 1:1 to form the light-diffusing film 2, and the mass fraction of the light-diffusing particles in the light-diffusing film 2 is 0.5%.

[0130] [Comparative Example 1] This comparative example is similar to Example 2, except that the mass fraction of the light-diffusing particles in the comparative light-diffusing film 1 formed is 5%.

[0131] The light diffusion films obtained in Examples 1 and 2 and the comparative light diffusion film obtained in Comparative Example 1 were placed on the side of a polarizing plate away from the display panel, and the polarizing plate was attached to the surface of a 75-inch liquid crystal display panel to perform an optical effect test, the results of which are shown in Table 1. The polarizing plate to be tested included a compensation layer, a polarizing layer, a protective layer, a light diffusion film (or a comparative light diffusion film), and a transparent cured sub-layer, which were laminated in this order.

[0132] The haze is measured using a haze measuring instrument NDH7000.

[0133] The dark state ratio refers to the ratio between the luminance of the display panel observed when the display panel is in a dark state and the center of the display panel is at an angle of 30° or 60°, and the luminance of the display panel when the display panel is in a dark state and the center of the display panel.

[0134] Contrast is the ratio of the luminance of the display panel in the white state to the luminance of the display panel in the dark state. In this test, the central luminance of the display panel in the white state and the central luminance of the display panel in the dark state were measured.

[0135] The luminance viewing angle is the value of the lateral viewing angle corresponding to the case where the luminance at the lateral viewing angle is half that at the square viewing angle.

[0136] The transmittance is the ratio of the white state luminance to the emission luminance of the backlight module.

[0137] The chromaticity viewing angle measurement is a viewing angle measurement performed according to the CESI standard (CESI 0.03).

[0138] [Table 1]

[0139] Table 1 shows that light diffusing particles formed by mixing particles of different shapes provide a large chromaticity angle of view when their mass percentage in the light diffusing film is less than 3%, and that the contrast, light transmittance, etc. are significantly improved compared to contrast light diffusing film 1, whose mass percentage in the light diffusing film is 3% or more.

[0140] The light diffusion film provided by the present invention includes a substrate and light diffusion particles dispersed in the substrate, and the mass fraction of the light diffusion particles in the substrate is less than 3%. The present invention adds light diffusion particles having a mass fraction of less than 3% to the substrate of the light diffusion film, thereby improving the viewing angle of the polarizing plate by utilizing the refraction effect of the light diffusion particles on the light, avoiding the reduction of the emitted light caused by providing an additional film layer on the polarizing plate, and further improving the chromaticity viewing angle and contrast of a display device having the light diffusion film, and improving the light output rate of the display device.

[0141] The above provides a detailed description of the light diffusion film, polarizing plate, and display device provided in the examples of the present invention, and specific examples are applied to the text to describe the principles and embodiments of the present invention. However, the above description of the examples is intended to aid in understanding the method of the present invention and its central idea. At the same time, those skilled in the art will recognize that there are changes in the specific embodiments and application scope based on the idea of ​​the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A light diffusing film, A substrate and light diffusing particles dispersed within the substrate, The mass fraction of the light diffusing particles in the substrate is less than 3%; A light diffusing film characterized by:

2. the light diffusing particles include a first type of light diffusing particles; the first type light diffusing particles include a plurality of first cross sections; each of the first cross sections includes a first circumscribing circle; a ratio of a major axis length of the first type light diffusing particle to a diameter of the first circumscribing circle having a maximum diameter among the plurality of first circumscribing circles is 5 or more; a ratio of a major axis length of the first type light diffusing particle to a diameter of the first circumscribing circle having a maximum diameter among the plurality of first circumscribing circles is less than 100; The first cross section is perpendicular to the extension direction of the long axis of the first light diffusing particle.

2. The light diffusing film according to claim 1 .

3. the first type light diffusing particles are at least one selected from a first subtype light diffusing particle, a second subtype light diffusing particle, a third subtype light diffusing particle, a fourth subtype light diffusing particle, and a fifth subtype light diffusing particle, each having a different shape; a change in diameter of a first circumscribing circle of the first cross section of the first subtype light diffusing particle along an extension direction of the major axis of the first subtype light diffusing particle is 0.3 micrometers or less; a change in diameter of a first circumscribing circle of the first cross section located at a middle part of the second subtype light diffusing particle along an extension direction of the long axis of the second subtype light diffusing particle is 1 micrometer or less, a change in diameter of the first circumscribing circle of the first cross section located at a first end part of the second subtype light diffusing particle along a direction away from the middle part of the second subtype light diffusing particle gradually decreases, and a change in diameter of the first circumscribing circle of the first cross section located at a second end part of the second subtype light diffusing particle is 1 micrometer or less, along the extension direction of the major axis of the third subtype light diffusing particle, the change in diameter of the first circumscribing circle of the first cross section located at a middle part of the third subtype light diffusing particle is 1 micrometer or less, along the direction away from the middle part of the third subtype light diffusing particle, the diameter of the first circumscribing circle of the first cross section located at a first end of the third subtype light diffusing particle gradually decreases, and the diameter of the first circumscribing circle of the first cross section located at a second end of the third subtype light diffusing particle gradually decreases, a first end of the fourth sub-type light diffusing particle is connected to a second end of the fourth sub-type light diffusing particle, and a diameter of a first circumscribing circle of the first cross section of the fourth sub-type light diffusing particle gradually decreases along a direction from the first end of the fourth sub-type light diffusing particle to the second end of the fourth sub-type light diffusing particle; a first end of the fifth subtype light diffusing particle is connected to a second end of the fifth subtype light diffusing particle, and a diameter of a first circumscribing circle of the first cross section located at the first end of the fifth subtype light diffusing particle gradually decreases along a direction away from the second end of the fifth subtype light diffusing particle, and a diameter of a first circumscribing circle of the first cross section located at the second end of the fifth subtype light diffusing particle gradually decreases along a direction away from the first end of the fifth subtype light diffusing particle.

3. The light diffusing film according to claim 2.

4. the light diffusing particles further comprise a second type of light diffusing particles; the second type light diffusing particles include a plurality of second cross sections; each said second cross section includes a second circumscribing circle; a ratio of a major axis length of the second type light diffusing particle to a diameter of the second circumscribing circle having a maximum diameter among the plurality of second circumscribing circles is 1 or more; a ratio of a major axis length of the second type light diffusing particle to a diameter of the second circumscribing circle having a maximum diameter among the plurality of second circumscribing circles is less than 5, and the second cross section is perpendicular to an extension direction of the major axis of the second type light diffusing particle.

4. The light diffusing film according to claim 3.

5. the second type light diffusing particles are at least one selected from a sixth subtype light diffusing particle, a seventh subtype light diffusing particle, an eighth subtype light diffusing particle, a ninth subtype light diffusing particle, and a tenth subtype light diffusing particle, each having a different shape; the change in diameter of the second circumscribing circle of the second cross section of the sixth sub-type light diffusing particle along the extending direction of the long axis of the sixth sub-type light diffusing particle is 0.3 micrometers or less; a first end of the seventh subtype light diffusing particle is connected to a second end of the seventh subtype light diffusing particle, and a diameter of a second circumscribing circle of the second cross section located at the first end of the seventh subtype light diffusing particle gradually decreases along a direction away from the second end of the seventh subtype light diffusing particle; and a diameter of a second circumscribing circle of the second cross section located at the second end of the seventh subtype light diffusing particle gradually decreases along a direction away from the first end of the seventh subtype light diffusing particle; a change in diameter of the second circumscribing circle of the second cross section located at a middle part of the 8th subtype light diffusing particle along an extension direction of the long axis of the 8th subtype light diffusing particle is 1 micrometer or less, a change in diameter of the second circumscribing circle of the second cross section located at a first end of the 8th subtype light diffusing particle along a direction away from the middle part of the 8th subtype light diffusing particle gradually decreases, and a change in diameter of the second circumscribing circle of the second cross section located at a second end of the 8th subtype light diffusing particle is 1 micrometer or less, along the extension direction of the major axis of the 9th subtype light diffusing particle, the change in diameter of the second circumscribing circle of the second cross section located at a middle part of the 9th subtype light diffusing particle is 1 micrometer or less, along the direction away from the middle part of the 9th subtype light diffusing particle, the diameter of the second circumscribing circle of the second cross section located at a first end of the 9th subtype light diffusing particle gradually decreases, and the diameter of the second circumscribing circle of the second cross section located at a second end of the 9th subtype light diffusing particle gradually decreases, a first end of the 10th sub-type light diffusing particle is connected to a second end of the 10th sub-type light diffusing particle, and a diameter of a second circumscribing circle of the second cross section of the 10th sub-type light diffusing particle gradually decreases along a direction from the first end of the 10th sub-type light diffusing particle to the second end of the 10th sub-type light diffusing particle; 5. The light diffusing film according to claim 4.

6. the first subtype light diffusing particles are selected from rod-shaped particles; the second subtype light diffusing particles are selected from needle-shaped particles having a smaller diameter at one end; the third subtype light diffusing particles are selected from needle-shaped particles having a diameter decreasing at both ends; The fourth subtype light diffusing particles are selected from long tapered particles; The fifth subtype light diffusing particles are selected from double tapered particles and / or oval spherical particles; The sixth subtype light diffusing particles are selected from cuboid particles or rectangular parallelepiped particles; The seventh sub-type light diffusing particles are selected from spherical particles or ellipsoidal particles; The eighth subtype light diffusing particles are selected from needle-shaped particles having a smaller diameter at one end; The ninth subtype light diffusing particles are selected from needle-shaped particles having a diameter decreasing at both ends; The tenth subtype light diffusing particles are selected from long tapered particles; 6. The light diffusing film according to claim 5.

7. The mass fraction of the fifth subtype light diffusing particles in the light diffusing particles is 20% or more; The mass fraction of the fifth subtype light diffusing particles in the light diffusing particles is 100% or less.

4. The light diffusing film according to claim 3.

8. the light diffusing particles have an average particle size, The length of a major axis of any one of the light diffusing particles is 20% or more of the average particle diameter of the light diffusing particles, The major axis length of any one of the light diffusing particles is 180% or less of the average particle diameter of the light diffusing particles.

2. The light diffusing film according to claim 1 .

9. The substrate includes a first sub-substrate and / or a second sub-substrate; The first sub-substrate is at least one selected from the group consisting of unmodified polyester and unmodified acetate fiber; The second sub-substrate is at least one selected from the group consisting of modified polyester and modified acetate cellulose; The mass fraction of the first sub-substrate in the substrate is 65% or more, and the mass fraction of the first sub-substrate in the substrate is 100% or less, The mass fraction of the second sub-substrate in the substrate is 0% or more, and the mass fraction of the second sub-substrate in the substrate is 35% or less.

2. The light diffusing film according to claim 1 .

10. A polarizing plate, The light diffusing film according to any one of claims 1 to 9, A polarizing plate characterized by:

11. A display device, comprising: The polarizing plate according to claim 10, A display device comprising:

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