Diffusion film, backlight module and display device

Abstract

The invention relates to a diffusion film, a backlight module and a display device. A first color conversion material is distributed in the diffusion film; wherein the first color conversion material is configured to absorb light, located in a preset wave band, in preset light rays and excite first light rays, and the proportion of the light of the first wave band in the spectrum of the first light rays is larger than that of the light of the first wave band in the spectrum of the preset light rays; a first color conversion material is additionally arranged in a diffusion film, the first color conversion material is configured to absorb light located in a preset wave band in preset light and excite first light, and the proportion of the light of the first wave band in the spectrum of the first light is larger than the proportion of the light of the first wave band in the spectrum of the preset light; when the diffusion film is used in the backlight module, the emergent light in the first wave band in the backlight module can be increased, the continuity of the emergent light spectrum of the backlight module is improved, the emergent light of the backlight module is closer to natural light, and the purpose of protecting eyes can be achieved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a diffusion film, a backlight module and a display device. Background Art

[0002] In a light-emitting diode (LED) backlight module, blue light LEDs are often combined with fluorescent materials. The fluorescent materials can absorb the blue light emitted by the blue LEDs and convert it into light of other colors, which are finally mixed to form white light.

[0003] However, the spectrum of white light generated in current LED backlight modules is discontinuous and differs greatly from the spectrum of sunlight. This discontinuous white light with dispersed luminous peaks has a greater stimulation on the visual cells in the human eye and can easily cause visual fatigue. Summary of the Invention

[0004] The embodiments of the present application provide a diffusion film, a backlight module, and a display device, which can supplement the light within a first wavelength band in the backlight module, so that the light emitted by the backlight module is closer to natural light.

[0005] The embodiment of the present application provides a diffusion film having a first color conversion material distributed therein;

[0006] The first color conversion material is configured to absorb light in a first preset wavelength band in a preset light and stimulate a first light, wherein the proportion of light in the first wavelength band in the spectrum of the first light is greater than the proportion of light in the first wavelength band in the spectrum of the preset light.

[0007] In one embodiment of the present application, the first color conversion material includes a fluorescent material, the first wavelength band is 470 nm to 530 nm, and the first preset wavelength band is 400 nm to 460 nm.

[0008] In one embodiment of the present application, a second color conversion material is further distributed in the diffusion film. The second color conversion material is configured to absorb light in a second preset wavelength band in the preset light and stimulate a second light. The proportion of light in the second wavelength band in the spectrum of the second light is greater than the proportion of light in the second wavelength band in the spectrum of the preset light, and the maximum value of the second wavelength band is greater than the maximum value of the first wavelength band. The second wavelength band is 570 nm to 620 nm.

[0009] And / or, a third color conversion material is also distributed in the diffusion film, and the third color conversion material is configured to absorb light in the preset light within a third preset band and stimulate a third light, the proportion of light in the third band in the spectrum of the third light is greater than the proportion of light in the third band in the spectrum of the preset light, and the maximum value of the third band is greater than the maximum value of the first band, wherein the third band is 690nm to 800nm.

[0010] In one embodiment of the present application, the diffusion film includes a substrate layer and a first coating layer and a second coating layer located on opposite sides of the substrate layer. The first color conversion material is distributed in at least one of the substrate layer, the first coating layer, and the second coating layer.

[0011] In one embodiment of the present application, the diffusion film includes a substrate layer and diffusion particles distributed in the substrate layer, and the first color conversion material is distributed in the substrate layer.

[0012] According to the above-mentioned purpose of the present application, an embodiment of the present application further provides a backlight module, which includes a light-emitting component and the diffusion film, and the diffusion film is arranged on the light-emitting side of the light-emitting component.

[0013] In one embodiment of the present application, the light-emitting assembly includes a light-emitting element, which includes a light source and a color conversion portion located on the light-emitting side of the light source, and the color conversion portion is configured to convert the light emitted by the light source into the preset light.

[0014] In one embodiment of the present application, a fourth color conversion material is distributed in the color conversion portion, and the fluorescence lifetime thermal stability of the fourth color conversion material is higher than that of the first color conversion material.

[0015] In one embodiment of the present application, the backlight module further includes an optical film group, and the diffusion film is located between the light-emitting component and the optical film group.

[0016] According to the above-mentioned purpose of the present application, an embodiment of the present application further provides a display device, which includes a display panel and the backlight module, and the display panel is located on the light-emitting side of the backlight module.

[0017] The present application provides a diffusion film, a backlight module and a display device. A first color conversion material is added to the diffusion film, and the first color conversion material is configured to absorb light in a first preset wavelength band in a preset light and stimulate a first light. The proportion of light in the first wavelength band in the spectrum of the first light is greater than the proportion of light in the first wavelength band in the spectrum of the preset light. Therefore, when the diffusion film is used in the backlight module, the light output in the first wavelength band of the backlight module can be increased, the continuity of the light output spectrum of the backlight module can be increased, and the light output of the backlight module can be made closer to natural light, thereby achieving the purpose of eye protection.

[0018] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0020] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same drawing numbers represent the same parts in the following description.

[0021] Figure 1 A schematic diagram of the first structure of the diffusion membrane provided in an embodiment of the present application;

[0022] Figure 2 An absorption / fluorescence spectrum of a first color conversion material provided in an embodiment of the present application;

[0023] Figure 3 A schematic diagram of the second structure of the diffusion membrane provided in an embodiment of the present application;

[0024] Figure 4 A third structural schematic diagram of the diffusion membrane provided in an embodiment of the present application;

[0025] Figure 5 A fourth structural schematic diagram of the diffusion membrane provided in an embodiment of the present application;

[0026] Figure 6 A schematic structural diagram of a backlight module provided in an embodiment of the present application;

[0027] Figure 7 A schematic structural diagram of a light-emitting element provided in an embodiment of the present application;

[0028] Figure 8 Another structural diagram of the backlight module provided in an embodiment of the present application;

[0029] Figure 9 This is a graph showing the luminous spectra of the backlight modules in the embodiments and comparative examples provided in the present application;

[0030] Figure 10 A schematic structural diagram of a display device provided in an embodiment of the present application.

[0031] Description of reference numerals:

[0032] 10. Diffusing film; 11. Base material layer; 111. Scattering particles; 12. First coating layer; 121. First particles; 13. Second coating layer; 131. Second particles; 14. First color conversion material;

[0033] 20. Light-emitting assembly; 21. Light-emitting element; 221. Light source; 212. Color conversion unit; 2121. Fourth color conversion material; 2122. Encapsulation layer; 22. Reflective film; 23. Light guide plate;

[0034] 30. Optical film assembly; 31. Prism sheet; 32. Additional diffusion film;

[0035] 40. Display panel; 41. Panel body; 42. First polarizer; 43. Second polarizer. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0037] Please refer to Figure 1 , an embodiment of the present application provides a diffusion film, wherein a first color conversion material 14 is distributed in the diffusion film 10 .

[0038] The first color conversion material 14 is configured to absorb light in a first preset wavelength band in a preset light and stimulate a first light, wherein the proportion of light in the first wavelength band in the spectrum of the first light is greater than the proportion of light in the first wavelength band in the spectrum of the preset light.

[0039] In the current backlight module, the spectrum of white light generated is discontinuous and significantly different from the spectrum of sunlight. Furthermore, the backlight module lacks blue-green, orange, and deep red light, resulting in discontinuous white light with dispersed luminous peaks. This significantly stimulates the visual cells in the human eye and can easily cause visual fatigue. However, in the embodiment of the present application, the first color conversion material 14 is added to the diffuser film 10. The first color conversion material 14 is configured to absorb light within a first preset wavelength band in the preset light and stimulate the first light. The proportion of light within the first wavelength band in the spectrum of the first light is greater than the proportion of light within the first wavelength band in the spectrum of the preset light. Consequently, when the diffuser film 10 is used in the backlight module, the light output within the first wavelength band in the backlight module can be increased, the continuity of the light output spectrum of the backlight module can be increased, and the light output of the backlight module can be closer to natural light, thereby achieving the purpose of eye protection.

[0040] For details, please refer to Figure 1 The diffusion film 10 provided in the embodiment of the present application is distributed with a first color conversion material 14, and the diffusion film 10 can have multiple film layers or only one film layer. When the diffusion film 10 has multiple film layers, the first color conversion material 14 can be distributed in any one of the multiple film layers or any multiple film layers.

[0041] It should be noted that diffusion particles are also distributed in the diffusion film 10 to achieve the light diffusion function of the diffusion film 10 .

[0042] In the embodiment of the present application, the first color conversion material 14 may include a fluorescent material; it should be noted that the diffusion film 10 will undergo a high-temperature process during the film formation process, and the temperature will reach above 200°C, and the fluorescent material can withstand high temperatures above 200°C. Therefore, the embodiment of the present application can incorporate the first color conversion material 14 into the diffusion film 10; compared with related technologies, the temperature that quantum dot materials can withstand is generally below 85°C, and thus quantum dot materials cannot withstand the film formation temperature of the diffusion film 10. Therefore, in the embodiment of the present application, the first color conversion material 14 is selected from fluorescent materials, which is more conducive to realizing the design and function of the diffusion film 10.

[0043] In some embodiments, the first color conversion material 14 includes a fluorescent material, and the first wavelength band is 470nm to 530nm; therefore, the first color conversion material 14 can be used to absorb light in the first preset wavelength band in the preset light and stimulate blue-green light, that is, cyan light; and then when the diffusion film 10 is used in the backlight module, it can supplement the blue-green light in the light output of the backlight module to increase the continuity of the light output of the backlight module, so that the light output of the backlight module is closer to natural light, reducing the damage of the light output of the backlight module to the human eye, and realizing the eye protection function.

[0044] In some embodiments, the first preset wavelength band is 400nm to 460nm, that is, the light within the first preset wavelength band can be purple-blue light; it should be noted that the first color conversion material absorbs light within the first preset wavelength band, which does not mean that the first color conversion material will absorb all light within the first preset wavelength band to excite the first light. The absorption of light within the first preset wavelength band by the first color conversion material can be regarded as the light absorbed by the first color conversion material being within the first preset wavelength band, that is, the light absorbed by the first color conversion material can be part of the light within the first preset wavelength band or all of the light.

[0045] In some embodiments, the first color conversion material 14 may include an inorganic material or an organic material; for example, the inorganic material may be selected from the group consisting of (Ca, Sr, Ba)4Al 14 O 25 :Eu 2+ The phosphor and the chemical formula is (Ca, Sr, Ba) 8MgSi4O 16 (F,Cl,Br)2:Eu 2+ At least one of the phosphors; the organic material can be selected from organic boron nitrogen coordination compounds.

[0046] In some embodiments, the organic boron nitrogen coordination compound can be selected from at least one of the following compounds:

[0047]

[0048] It should be noted that the embodiments of this application are for fluorescent materials The absorption / fluorescence spectrum of Figure 2 The spectrum shown is Figure 2 It can be seen that the material can absorb light in the wavelength band of 380nm-465nm and excite blue-green light in the wavelength band of 440nm-550nm.

[0049] In some embodiments, a second color conversion material is also distributed in the diffusion film 10, and the second color conversion material is configured to absorb light in the preset light within a second preset band and stimulate a second light. The proportion of light in the second band in the spectrum of the second light is greater than the proportion of light in the second band in the spectrum of the preset light, and the maximum value of the second band is greater than the maximum value of the first band, wherein the second band is 570nm to 620nm; that is, the second color conversion material can be used to stimulate orange light; and then the orange light in the light output of the backlight module can be supplemented to increase the continuity of the light output of the backlight module, so that the light output of the backlight module is closer to natural light, reducing the damage of the light output of the backlight module to the human eye, and realizing the eye protection function.

[0050] In some embodiments, the second preset wavelength band may include the first preset wavelength band and the first wavelength band, that is, the second preset wavelength band may be 470nm to 530nm and 400nm to 460nm, or the second preset wavelength band may be 400nm to 530nm; it should be noted that the second color conversion material absorbs light within the second preset wavelength band, which does not mean that the second color conversion material will absorb all light within the second preset wavelength band to excite the second light. The absorption of light within the second preset wavelength band by the second color conversion material can be regarded as the light absorbed by the second color conversion material being within the second preset wavelength band, that is, the light absorbed by the second color conversion material may be part of the light within the second preset wavelength band or all of the light.

[0051] In some embodiments, a third color conversion material is also distributed in the diffusion film 10, and the third color conversion material is configured to absorb light in the preset light within a third preset band and stimulate a third light. The proportion of light in the third band in the spectrum of the third light is greater than the proportion of light in the third band in the spectrum of the preset light, and the maximum value of the third band is greater than the maximum value of the first band, wherein the third band is 690nm to 800nm; that is, the second color conversion material can be used to stimulate deep red light; and then the deep red light in the light output of the backlight module can be supplemented to increase the continuity of the light output of the backlight module, so that the light output of the backlight module is closer to natural light, reducing the damage of the light output of the backlight module to the human eye, and realizing the eye protection function.

[0052] In some embodiments, the third preset wavelength band may include the first preset wavelength band and the first wavelength band, that is, the third preset wavelength band may be less than or equal to 620 nm; it should be noted that the absorption of light within the third preset wavelength band by the third color conversion material does not mean that the third color conversion material will absorb all light within the third preset wavelength band to excite the third light, and the absorption of light within the third preset wavelength band by the third color conversion material can be regarded as the light absorbed by the third color conversion material being within the third preset wavelength band, that is, the light absorbed by the third color conversion material may be part of the light within the third preset wavelength band or all of the light.

[0053] In other embodiments of the present application, the diffusion film 10 may be doped with other color conversion materials to supplement light in other bands in the light output spectrum of the backlight module, so as to further improve the continuity of the light output spectrum of the backlight module and make the light output spectrum of the backlight module closer to natural light.

[0054] In some embodiments, as Figure 1 As shown, the diffusion film 10 may include a substrate layer 11 and a first coating layer 12 and a second coating layer 13 located on opposite sides of the substrate layer 11 , and the first color conversion material 14 is distributed in at least one of the substrate layer 11 , the first coating layer 12 and the second coating layer 13 .

[0055] It can be understood that the second color conversion material can also be distributed in at least one of the substrate layer 11, the first coating layer 12 and the second coating layer 13; the third color conversion material can also be distributed in at least one of the substrate layer 11, the first coating layer 12 and the second coating layer 13; and the distribution selection of the first color conversion material 14, the second color conversion material and the third color conversion material does not affect each other; and the distribution position of the first color conversion material 14 is used as an example in the following description of the embodiment of the present application.

[0056] In a specific embodiment of this application, please refer to Figure 1 The first coating layer 12 and the second coating layer 13 are located on opposite sides of the substrate layer 11. The substrate layer 11 may be made of optical-grade polyester film (PET) or polycarbonate (PC). The thickness of the substrate layer 11 is typically 75 μm to 188 μm. The transmittance of the substrate layer 11 is greater than or equal to 88%, and the substrate layer 11 has a low shrinkage rate. The substrate layer 11 serves as a carrier supporting the upper and lower functional layers and requires high temperature resistance and mechanical strength. For example, the substrate layer 11 may be selected from PET substrates from manufacturers such as Toray and SKC.

[0057] In some embodiments, the material of the first coating layer 12 is formed by mixing first particles 121 in a transparent resin, and the first particles 121 can be formed of hard scattering particles; wherein the transparent resin can include polyester or acrylic resin, and the material of the hard scattering particles can include at least one of polymethyl methacrylate and polystyrene; the particle size of the hard scattering particles ranges from 1 μm to 10 μm. wherein the first coating layer 12 can be formed by coating, and then formed into a film by a thermal curing or UV curing process. the first coating layer 12 is configured to induce light scattering by the difference in refractive index between the hard scattering particles and the transparent resin, thereby forming a uniform surface light source. for example, the material of the hard scattering particles is polymethyl methacrylate, and has a refractive index of 1.49; the material of the transparent resin is a polyester film, and has a refractive index of 1.65.

[0058] In some embodiments, the second coating layer 13 may be based on an acrylic resin or polyurethane, and second particles 131 may be incorporated into the base. The second particles 131 may be micron-sized soft particles, forming a concave-convex structure on the surface of the second coating layer 13. This prevents the diffusion film 10 from directly contacting other film layers in the backlight module, thereby preventing the generation of adsorption white spots or scratches, and reducing optical interference (such as Newton rings) through point contact. The material of the micron-sized soft particles may include at least one of polybutyl methacrylate and polyamide.

[0059] In this embodiment, the first color conversion material 14 can be distributed in the first coating layer 12, that is, the first color conversion material 14 and the first particles 121 are mixed into a transparent resin at the same time, and then formed into a film on the surface of the substrate layer 11, so as to simultaneously achieve the functions of uniform surface light source and color conversion.

[0060] In another specific embodiment of this application, please refer to Figure 3 , and Figure 1 The embodiment shown differs in that the first color conversion material 14 is distributed in the second coating 13 .

[0061] The first color conversion material 14 and the second particles 131 are mixed into the matrix at the same time, and then formed into a film on the surface of the substrate layer 11 to simultaneously achieve the functions of preventing white spot adsorption, preventing scratches, reducing optical interference and color conversion.

[0062] In another specific embodiment of this application, please refer to Figure 4 , and Figure 1 The difference of the illustrated embodiment is that the first color conversion material 14 can be distributed in the substrate layer 11 .

[0063] The first color conversion material 14 is mixed into the material of the substrate layer 11 so that the substrate layer 11 has a color conversion function.

[0064] In another specific embodiment of this application, please refer to Figure 5 The diffusion film 10 includes a substrate layer 11 , and further includes the first color conversion material 14 and the scattering particles 111 distributed in the substrate layer 11 .

[0065] The first color conversion material 14 and the first particles 121 are mixed into the diffusion film 10 , so that the substrate layer 11 can simultaneously achieve the functions of support, scattering, and color conversion.

[0066] In addition, the embodiment of the present application also provides a preparation process of the diffusion membrane 10 described in the above embodiment.

[0067] The first color conversion material 14 is mixed into a film-forming material, and then formed into a film through a coating process or a stretching process.

[0068] In a specific embodiment, please combine Figure 3 and Figure 4 First, the phosphor (the first color conversion material 14) is mixed into the resin, and a solvent is added and stirred thoroughly to form a solution; wherein the phosphor accounts for 1% to 10% of the total solid mass.

[0069] The resin can be the transparent resin material in the first coating 12 or the matrix material in the second coating 13. The solid content of the resin is 5-25%, preferably 15%, and the solvent includes ethyl acetate, butyl acetate, tetrahydrofuran, etc., preferably ethyl acetate.

[0070] Then, a thermosetting additive is added, the coating is applied to form a film, the solvent is heated to dry, and the resin is further cross-linked to obtain the first coating 12 or the second coating 13; and the film thickness is 10 to 40 μm. The thermosetting additive includes but is not limited to isocyanate additives.

[0071] Then, it is compounded with other film layer structures (such as the substrate layer 11); wherein, the first coating layer 12 obtained in the above step can be compounded with the substrate layer 11 and the second coating layer 13 to obtain the diffusion film 10; or the second coating layer 13 obtained in the above step can be compounded with the substrate layer 11 and the first coating layer 12 to obtain the diffusion film 10.

[0072] In another specific embodiment, please refer to Figure 1First, add phosphor powder (the first color conversion material 14) to the polymer particles and stir and mix; specifically, the phosphor powder can be added to the material of the substrate layer 11. The phosphor accounts for 1% to 10% of the total mass fraction.

[0073] Then, the mixture is added to the film-forming feeding system;

[0074] Then, the substrate layer 11 is obtained by extrusion and stretching to form a film with a thickness of 20-80 μm.

[0075] The substrate layer 11 is compounded with other film layer structures (such as the first coating layer 12 and the second coating layer 13 ) to obtain the diffusion film 10 .

[0076] In addition, please refer to Figure 1 as well as Figure 6 The embodiment of the present application provides a backlight module, which includes a light emitting component 20 and a diffusion film 10 as described in the above embodiment. The diffusion film 10 is arranged on the light emitting side of the light emitting component 20.

[0077] In some embodiments, the light emitting assembly 20 includes a light emitting element 21 and some functional film layers, and the functional film layers can be used to adjust the light emitted by the light emitting element 21 to be emitted in a forward direction toward the backlight module.

[0078] Please combine Figure 6 and Figure 7 , the light-emitting assembly 20 includes a light-emitting element 21, which includes a light source 211 and a color conversion portion 212 located on the light-emitting side of the light source 211; and the color conversion portion 212 is configured to convert the light emitted by the light source 211 into the preset light.

[0079] It can be understood that the color conversion unit 212 converts the light emitted by the light source 211 into the preset light, and when the preset light reaches the diffusion film 10, part of the preset light is absorbed by the first color conversion material 14, that is, the light in the preset light that is within the first preset band, and stimulates the first light, and the light in the first band accounts for a large proportion of the first light. Then, after the first light is mixed with the preset light, the light in the first band in the emitted light can be supplemented to improve the continuity of the light output spectrum of the backlight module.

[0080] In some embodiments, a fourth color conversion material 2121 is distributed in the color conversion portion 212, and the fluorescence lifetime thermal stability of the fourth color conversion material 2121 is higher than the fluorescence lifetime thermal stability of the first color conversion material 14; since the light source 211 generates heat during the light-emitting process, the temperature of the color conversion portion 212 becomes higher during the operation of the backlight module, and high temperature reduces the stability and life of the color conversion material; therefore, the embodiment of the present application can additionally arrange the first color conversion material 14 with poor fluorescence lifetime thermal stability in the diffusion film 10 to keep it away from the light source 211, thereby increasing the stability and service life of the first color conversion material 14, and at the same time reducing the secondary absorption of the internal light of the first wavelength band in the color conversion portion 212, thereby improving the light extraction efficiency of the light of the first wavelength band.

[0081] The color conversion unit 212 further includes an encapsulation layer 2122 covering the light source 211 , and the fourth color conversion material 2121 may be distributed in the encapsulation layer 2122 .

[0082] It should be noted that the water and oxygen resistance of the first color conversion material 14 is weaker than that of the fourth color conversion material. Therefore, in the embodiment of the present application, the first color conversion material 14 is not set in the encapsulation layer 2122, thereby improving the lifespan and light extraction efficiency of the first color conversion material 14.

[0083] In some embodiments, the light source 211 can be a blue LED lamp for emitting blue light; and the fourth color conversion material 2121 can include at least one of a red fluorescent material, a green fluorescent material, and a yellow fluorescent material; and then the fourth color conversion material 2121 can absorb blue light and convert it into at least one of red light, green light, and yellow light, and mix it with the blue light emitted by the light source 211 to form white light, that is, the preset light; after the preset light passes through the diffusion film 10, the relatively missing bands in the white light can be supplemented, so that the supplemented white light is closer to natural light, so as to reduce the damage of the light output of the backlight module to the human eye.

[0084] like Figure 6 As shown, when the light emitting assembly 20 is a direct-down structure, the light emitting assembly 20 further includes a reflective film 22 , and the light emitting element 21 is disposed on the reflective film 22 to allow more light emitted by the light emitting element 21 to be emitted in the forward direction of the backlight module.

[0085] like Figure 8As shown, when the light-emitting component 20 is a side-entry structure, the light-emitting component 20 further includes a reflective film 22 and a light guide plate 23, and the diffusion film 10 and the reflective film 22 are respectively arranged on opposite sides of the light guide plate 23, and the light-emitting element 21 is located on the side of the light guide plate 23. The preset light emitted by the light-emitting element 21 is adjusted by the light guide plate 23 and the reflective film 22, and can be emitted in the direction of the diffusion film 10.

[0086] In some embodiments, the backlight module also includes an optical film group 30, and the diffusion film 10 can be located between the light-emitting component 20 and the optical film group 30, so that the optical film group 30 can improve and adjust the light output effect of all light passing through the diffusion film 10, so as to maximize the light output effect of the backlight module.

[0087] In some embodiments, the optical film group 30 includes a prism sheet 31 arranged on the side of the diffusion film 10 away from the light-emitting component 20 and an additional diffusion film 32 located on the side of the prism sheet 31 away from the diffusion film 10; it can be understood that the first color conversion material can also be distributed in the additional diffusion film 32.

[0088] Furthermore, the present embodiment provides examples and comparative examples to verify the light emission of a backlight module including the diffusion film 10 provided in the present embodiment.

[0089] In an embodiment, Figure 3 As shown, 0.45 g of the first color conversion material 14 is mixed into 72.75 g of resin (acrylic resin with a solid content of 20%), where the first color conversion material 14 accounts for 3% of the total solid content. 26.80 g of ethyl acetate is then added and stirred for 6 hours to prepare a mixed solution with a solid content of 15%.

[0090] Wherein, the first color conversion material 14 is

[0091] Then, 0.01 g of isocyanate was added, stirred for 30 minutes, and coated to form a film. The film was heated at 85° C. to dry the solvent and further cross-link the resin to form a 15 mm optical film layer, thereby obtaining the second coating layer 13 .

[0092] The second coating layer 13 is compounded with the substrate layer 11 and the first coating layer 12 to obtain Figure 3 The structure of the diffusion film 10 is shown.

[0093] In the comparative example, the same Figure 3The structure of the diffusion film 10 shown is the same as that of the diffusion film 10 , except that the first color conversion material 14 is not added to the second coating layer 13 .

[0094] Optical testing

[0095] The diffusion membranes obtained in the examples and comparative examples were used as follows: Figure 6 The backlight module in the embodiment and the comparative example were tested respectively to obtain the spectrum of the backlight module. Figure 9 The spectral curve shown.

[0096] Figure 9 In the embodiment, curve A is the light spectrum curve of the backlight module, and curve B is the light spectrum curve of the backlight module in the comparative example; Figure 9 It can be seen that the spectrum of curve A in the band of 440nm-600nm is more continuous and closer to the effect of natural light; that is, it shows that the use of the diffusion film 10 provided in the embodiment of the present application can effectively increase the light output within the first band in the backlight module, increase the continuity of the light output spectrum of the backlight module, and make the light output of the backlight module closer to natural light, which can achieve the purpose of eye protection.

[0097] In addition, please refer to Figure 10 , an embodiment of the present application further provides a display device, which includes a display panel 40 and a backlight module as described in the above embodiment, wherein the display panel 40 is located on the light-emitting side of the backlight module.

[0098] In some embodiments, the display panel 40 is disposed on a side of the optical film assembly 30 away from the diffusion film 10 .

[0099] The display panel 40 may include a panel body 41 , a first polarizer 42 disposed between the panel body 41 and the optical film assembly 30 , and a second polarizer 43 located on a side of the panel body 41 away from the first polarizer 42 .

[0100] In some embodiments, the panel body 41 may be a liquid crystal display panel.

[0101] In summary, the embodiment of the present application adds the first color conversion material 14 to the diffusion film 10, and the first color conversion material 14 is configured to absorb the light in the first preset band in the preset light and stimulate the first light. The proportion of the light in the first band in the spectrum of the first light is greater than the proportion of the light in the first band in the spectrum of the preset light. Therefore, when the diffusion film 10 is used in the backlight module, the light output in the first band of the backlight module can be increased, and the continuity of the light output spectrum of the backlight module can be increased, so that the light output of the backlight module is closer to natural light, which can achieve the purpose of eye protection.

[0102] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0103] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0104] The embodiments, implementation methods and related technical features of the present application can be combined and replaced with each other unless there is any conflict.

[0105] The above are merely preferred embodiments of the present application and do not constitute any form of limitation to the present application. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A diffusion membrane, characterized in that A first color conversion material is distributed in the diffusion film; The first color conversion material is configured to absorb light in a first preset wavelength band in a preset light and stimulate a first light, wherein the proportion of light in the first wavelength band in the spectrum of the first light is greater than the proportion of light in the first wavelength band in the spectrum of the preset light.

2. The diffusion film according to claim 1, characterized in that The first color conversion material includes a fluorescent material, the first wavelength range is 470 nm to 530 nm, and the first preset wavelength range is 400 nm to 460 nm.

3. The diffusion film according to claim 1, characterized in that A second color conversion material is further distributed in the diffusion film. The second color conversion material is configured to absorb light in a second preset wavelength band in the preset light and stimulate a second light. The proportion of light in the second wavelength band in the spectrum of the second light is greater than the proportion of light in the second wavelength band in the spectrum of the preset light, and the maximum value of the second wavelength band is greater than the maximum value of the first wavelength band. The second wavelength band is 570 nm to 620 nm. And / or, a third color conversion material is also distributed in the diffusion film, and the third color conversion material is configured to absorb light in the preset light within a third preset band and stimulate a third light, the proportion of light in the third band in the spectrum of the third light is greater than the proportion of light in the third band in the spectrum of the preset light, and the maximum value of the third band is greater than the maximum value of the first band, wherein the third band is 690nm to 800nm.

4. The diffusion membrane according to any one of claims 1 to 3, characterized in that The diffusion film includes a substrate layer and a first coating layer and a second coating layer located on opposite sides of the substrate layer. The first color conversion material is distributed in at least one of the substrate layer, the first coating layer, and the second coating layer.

5. The diffusion membrane according to any one of claims 1 to 3, characterized in that The diffusion film includes a substrate layer and diffusion particles distributed in the substrate layer, and the first color conversion material is distributed in the substrate layer.

6. A backlight module, characterized in that: The backlight module includes a light-emitting component and the diffusion film according to any one of claims 1 to 5, wherein the diffusion film is arranged on the light-emitting side of the light-emitting component.

7. The backlight module according to claim 6, wherein: The light-emitting assembly includes a light-emitting element, which includes a light source and a color conversion portion located on a light-emitting side of the light source. The color conversion portion is configured to convert the light emitted by the light source into the preset light.

8. The backlight module according to claim 6, wherein: A fourth color conversion material is distributed in the color conversion portion, and the fourth color conversion material has a higher fluorescence lifetime thermal stability than that of the first color conversion material.

9. The backlight module according to claim 6, wherein: The backlight module further includes an optical film group, and the diffusion film is located between the light-emitting component and the optical film group.

10. A display device, characterized in that: The display device includes a display panel and the backlight module according to any one of claims 6 to 9, wherein the display panel is located on a light-emitting side of the backlight module.

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