CN113296312A

CN113296312A - Display device

Info

Publication number: CN113296312A
Application number: CN202110526332.3A
Authority: CN
Inventors: 宋庆欢; 许怀书; 邓天应; 季洪雷; 陈细俊
Original assignee: Huizhou Shiwei New Technology Co Ltd
Current assignee: Huizhou Shiwei New Technology Co Ltd
Priority date: 2021-05-14
Filing date: 2021-05-14
Publication date: 2021-08-24
Also published as: WO2022237256A1

Abstract

The present invention provides a display device including: a display screen; the backlight module is positioned below the display screen, and one side of the backlight module, which is close to the display screen, is provided with an optical composite film; the optical film composite film is attached to the display screen through the optical adhesive layer, the optical film composite film is attached to the display screen with excellent dimensional stability and low thermal expansion coefficient, the problem that the optical film composite film is prone to wrinkling due to severe changes of environmental humidity and temperature is solved, the problem that the optical film is poor in stiffness and prone to wrinkling is effectively solved, and the quality of the display device is improved.

Description

Display device

Technical Field

The invention relates to the technical field of display, in particular to a display device.

Background

With the development of liquid crystal display technology and the higher requirements of people on the display quality of liquid crystal display screens, large size, thinness and narrow frame become the development trend of liquid crystal display screens. In order to meet the requirements, the core competitiveness of the product is improved, display screen manufacturers pursue the maximization in the aspects of product scheme design and manufacturing process, and higher requirements are provided for the performance of the backlight module. The optical film is used as an important component of the backlight module, and the structure of the optical film is changed from four or three conventional optical films to two optical films (an upper brightness enhancement film and a lower brightness enhancement film) which are mainstream at present.

However, in the use process of the optical film, firstly, because the optical film has moisture absorption property, when the humidity of the external environment changes dramatically, the expansion and contraction of the film and different positions of the film in the optical film are uneven due to uneven humidity, so that the optical film is easy to generate wavy or water wave-shaped wrinkles, and the phenomenon is more obvious when the size is larger; secondly, since the thickness of a single optical film is only 220-290 micrometers (um), the optical film has poor stiffness and is easy to deform. In conclusion, the large-sized optical film in the prior art has the problems of poor stiffness and easy wrinkling.

Therefore, the prior art has defects and needs to be improved and developed.

Disclosure of Invention

The embodiment of the application provides a display device, can improve the poor and easy problem of fold of optical film stiffness effectively, has promoted liquid crystal display's quality.

In order to solve the above problem, the present invention provides a display device including: a display screen; the backlight module is positioned below the display screen, and one side of the backlight module, which is close to the display screen, is provided with an optical composite film; and the optical adhesive layer is positioned between the display screen and the optical composite film, and the optical composite film and the display screen are attached through the optical adhesive layer.

The optical composite film comprises an upper brightness enhancement film and a lower brightness enhancement film which are arranged in a stacked mode and are mutually bonded.

Wherein, go up brightness enhancement film and lower brightness enhancement film and all include the spotlight layer and the substrate layer of range upon range of setting, and brightness enhancement film still includes the diffusion layer that is located the substrate layer below down, and the spotlight layer includes at least one microprism structure.

Wherein, be equipped with the diffusion particle in the optical cement layer, the diffusion particle is used for diffusing light.

Wherein the diffusion particles comprise organic diffusion particles and/or inorganic diffusion particles.

Wherein, the material of the organic diffusion particles comprises any one or more of polymethyl methacrylate, polybutyl methacrylate, polystyrene, polyamide nylon, siloxane resin and organic silicon particles.

Wherein, the material of the inorganic diffusion particles comprises any one or more of silicon dioxide, titanium dioxide, aluminum oxide, zinc oxide, calcium carbonate and barium sulfate.

Wherein, the doping concentration of the diffusion particles in the optical adhesive layer is not more than 20%.

Wherein the refractive index and the haze of the optical adhesive layer are respectively 1.38-1.58 and 60-80%.

Wherein the thickness range of the optical adhesive layer comprises 1-30 micrometers.

The invention has the beneficial effects that: different from the prior art, an embodiment of the present invention provides a display device, including: a display screen; the backlight module is positioned below the display screen, and one side of the backlight module, which is close to the display screen, is provided with an optical composite film; and the optical adhesive layer is positioned between the display screen and the optical composite film, and the optical composite film and the display screen are attached through the optical adhesive layer. Through doping with the diffusion particle in the optical adhesive layer, the collocation parameter of the refracting index, haze and thickness of adjustment optical adhesive layer has improved the interference phenomenon with the pixel of display screen under the prerequisite of having guaranteed certain luminance, meanwhile, has improved the joint strength of optical composite film and display screen to display device's quality has been promoted.

Drawings

Fig. 1 is a schematic structural diagram of a display device according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an optical composite film according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of another optical composite film according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be noted that the following examples are only illustrative of the present invention, and do not limit the scope of the present invention. Likewise, the following examples are only some but not all examples of the present invention, and all other examples obtained by those skilled in the art without any inventive step are within the scope of the present invention.

In addition, directional terms mentioned in the present invention, such as [ upper ], [ lower ], [ front ], [ rear ], [ left ], [ right ], [ inner ], [ outer ], [ side ], and the like, refer to directions of the attached drawings only. Accordingly, the directional terms used are used for explanation and understanding of the present invention, and are not used for limiting the present invention. In the various figures, elements of similar structure are identified by the same reference numerals. For purposes of clarity, the various features in the drawings are not necessarily drawn to scale. Moreover, some well-known elements may not be shown in the figures.

The following disclosure provides many different embodiments or examples for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or uses of other materials.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings.

As shown in fig. 1, an embodiment of the present invention provides a display device 100, including: a display screen 110; a backlight module (not shown) located below the display screen 110, wherein an optical composite film 121 is disposed on a side of the backlight module close to the display screen 110; and the optical adhesive layer 122 is positioned between the display screen 110 and the optical composite film 121, and the optical composite film 121 and the display screen 110 are attached through the optical adhesive layer 122.

Specifically, the display device 100 mainly includes a Liquid Crystal Display (LCD), a Plasma Display Panel (PDP), an Organic Light Emitting Display (OLED), an Active Matrix Organic Light Emitting Display (AMOLED), and the like. The display principle of the display device 100 is that a control circuit and a driving circuit are arranged around the liquid crystal material, and when an electric field is generated by electrodes in the display device 100, liquid crystal molecules are distorted, so that light passing through the liquid crystal molecules is regularly refracted (the optical rotation of the liquid crystal material), and is filtered by a polarizer to be displayed on a screen, thereby displaying an image. However, since the liquid crystal molecules do not emit light, the display device 100 usually needs to be configured with an additional Backlight source, which is called a Backlight unit (BLU), for providing sufficient brightness and uniform light source to enable the display device 100 to normally display images. Currently, the backlight mainly used in the liquid crystal display includes: cold Cathode Fluorescent Lamp (CCFL) and Light Emitting Diode (LED). Because the LED light source has the advantages of high brightness, high color purity, long service life, good reliability, no mercury pollution and the like, the proportion occupied by the LED light source in the use of the backlight light source is gradually increased.

Specifically, the backlight module is divided into a side-in type backlight module and a direct type backlight module according to the position of the backlight source. The lateral backlight module comprises a light source, a light guide plate, a reflecting plate, a diffusing plate and an optical film (not shown in the figure), wherein the light source in the lateral backlight module is usually arranged on the peripheral side of the light guide plate, the reflecting plate is arranged on one side of the light source far away from the light guide plate, the diffusing plate and the optical film are arranged on one side close to the display screen 110, one part of horizontal light emitted by the backlight source directly passes through the light guide plate, the other part of horizontal light passes through the light guide plate after passing through the reflecting plate, the incident light is changed into vertical light by the light guide plate, and then the vertical light is converged through the sufficient scattering of the diffusing plate and the center of the optical film to provide sufficient brightness and uniformly distributed light for the display screen 110, so that the purpose of providing the light source for the display device 100 to enable the display device to display images is achieved. Wherein, straight following formula backlight unit includes the light source, the light guide plate, the reflecting plate, diffuser plate and optical film (not shown in the figure), light source among the straight following formula backlight unit sets up the below at the light guide plate usually, the reflecting plate sets up the one side of keeping away from the light guide plate below the light source, diffuser plate and optical film set up the one side of being close to display screen 110, in backlight unit, some direct process light guide plate of the perpendicular light of light source transmission, another part passes through the light guide plate after the reflector plate, the light guide plate becomes incident light, then after the center of perpendicular light through abundant scattering of diffuser plate and optical film assembles, give display screen 110 sufficient luminance and the even light of distribution, in order to realize providing the light source to display device 100 and make its purpose of showing the image.

In addition, the light guide plate functions to guide a scattering direction of light, to improve the brightness of the panel, and to ensure uniformity of the brightness of the panel. Whether the light guide plate is good or not greatly affects the backlight plate, so the design and manufacture of the light guide plate in the edge-lit backlight plate is one of the key technologies. The LED light source or the light bar in the side-entering type backlight module is positioned at the side edge of the light guide plate, the light emitted by the LED light source or the light bar is guided into the light guide plate by reflection, various dense and different-size diffusion points are arranged in the light guide plate, the light guide plate can uniformly emit light, when light rays irradiate the diffusion points, the reflected light can be diffused at various angles, and then the reflection condition is destroyed to be emitted from the front surface of the light guide plate. The purpose of the reflecting plate is to reflect the light exposed from the bottom surface back to the light guide plate, so as to improve the use efficiency of the light. Because the light emitted by the light source in the direct type backlight module is vertically upward, a light guide plate and a reflecting plate are not needed in the direct type backlight module, and the vertical incident light is directly emitted to the diffusing plate and the optical film.

In particular, the optical film is an important component of the backlight module, and during the use process of the backlight module, due to the characteristics of the optical film, the optical film is prone to poor stiffness and easy wrinkling. The optical composite film 121 is attached to one side, close to the backlight module, of the display screen 110 by using the optical adhesive layer 122, one side, close to the backlight module, of the display screen 110 is generally a glass substrate, the glass substrate can be divided into two types, namely alkali glass and alkali-free glass, and the glass substrate is generally made of a material with a very low thermal expansion coefficient. Because the thermal expansion coefficient of the glass substrate is very low, correspondingly, the proportion of the expansion or contraction of the appearance size of the glass substrate caused by the temperature change is also low, so that the cold and hot expansion of the liquid crystal display screen is reduced to the minimum. Through adopting optical composite film 121, rather than the traditional many independent optical films, the poor problem of singleton optical film stiffness has been improved, through with optical composite film 121 integrated on the display screen 110 that dimensional stability is excellent and coefficient of thermal expansion is low, the easy problem of fold that optical composite film 121 produced because environmental humidity, the violent change of temperature to improve the poor problem of easy fold of optical film stiffness effectively, and then promoted liquid crystal display's quality.

The optical composite film 121 includes an upper brightness enhancement film 123 and a lower brightness enhancement film 124 stacked and bonded to each other.

As shown in fig. 2, a schematic structural diagram of an optical composite film 121 provided in an embodiment of the present invention includes: the upper brightness enhancement film 123 and the lower brightness enhancement film 124 are stacked and bonded to each other, and preferably, the upper brightness enhancement film 123 and the lower brightness enhancement film 124 are attached by glue. Because the display screen 110 has a certain visual angle, the brightness is higher when the display screen is observed from the direction vertical to the display screen 110; however, the brightness is not very high when viewed from an angle with respect to a direction perpendicular to the display screen 110, and the light emitting efficiency can be improved by the upper and lower

brightness enhancement films

123 and 124. Generally, the upper brightness enhancement film 123 and the lower brightness enhancement film 124 are each composed of a three-layer structure of an upper layer, a middle layer and a lower layer, the upper layer is generally a functional layer for enhancing the brightness of light, the middle layer is generally a carrier layer for carrying a film layer of the functional layer, and the lower layer is generally a diffusion layer for diffusing light. The upper brightness enhancement film 123 and the lower brightness enhancement film 124 are bonded together through glue to form the optical composite film 121 with better stiffness, so that the problems of poor stiffness and easy deformation caused by the fact that the single-layer brightness enhancement film is large in size and small in thickness are solved, the optical composite film 121 is applied to a large-size liquid crystal display screen, the deformation caused by water ripples and insufficient stiffness due to uneven moisture absorption of an optical film can be improved to a certain extent, and the quality of the liquid crystal display screen is improved.

Specifically, the optical composite film 121(Up Prism on Prism, UPOP) refers to a composite film in which an upper brightness enhancement film 123 and a lower brightness enhancement film 124 are bonded together. The brightness enhancement film is a film or sheet applied to a backlight module of a liquid crystal display to improve the luminous efficiency of the whole backlight system. As shown in fig. 2, the brightness enhancement film positioned above the optical composite film 121 is referred to as an upper brightness enhancement film 123, and the brightness enhancement film positioned below the optical composite film is referred to as a lower brightness enhancement film 124. The brightness enhancement film is generally classified into four types, a general prism sheet (normal prism sheet), a multifunctional prism sheet, a multi-compound type optical film (micro-lens film), and a reflective polarizer. The prism sheet has the main function of guiding the light emitted from the light source to increase the light emitting efficiency; the multifunctional prism sheet integrates the functions of the prism sheet and the diffusion sheet, and has better luminous efficiency compared with the common prism sheet; the multi-compound optical film also integrates the functions of a prism sheet and a diffusion sheet into one film; the reflective polarizer, also called a Dual Brightness Enhancement Film (DBEF), is the highest luminous efficiency of all brightness enhancement films. In addition, go up brightness enhancement film 123 and lower brightness enhancement film 124 and laminate through the glue, the glue that adopts can be UV resin and thermosetting resin, when laminating the glue film and contain above-mentioned material, is favorable to making the glue layer have certain light transmissivity.

The upper brightness enhancement film 123 and the lower brightness enhancement film 124 both comprise a light-gathering layer and a substrate layer which are stacked, the lower brightness enhancement film 124 further comprises a diffusion layer located below the substrate layer, and the light-gathering layer comprises at least one micro-prism structure.

As shown in fig. 3, a schematic structural diagram of another optical composite film 121 provided in the embodiment of the present invention includes: the upper brightness enhancement film 123 and the lower brightness enhancement film 124 are stacked, wherein the upper brightness enhancement film 123 comprises a light-gathering layer and a base material layer which are stacked, the lower brightness enhancement film 124 comprises a light-gathering layer, a base material layer and a diffusion layer which are stacked, and the light-gathering layer comprises a plurality of micro-prism structures. Unlike the optical composite film 121 shown in fig. 2, the upper brightness enhancement film 123 has a reduced diffusion layer (not shown), and compared to a scheme in which the upper brightness enhancement film 123 and the lower brightness enhancement film 124 are separately attached, the overall thickness of the optical composite film 121 is reduced, and accordingly, the overall thickness of the display device 100 is reduced.

Specifically, the upper brightness enhancement film 123 and the lower brightness enhancement film 124 are configured to focus incident light rays within a central viewing angle (± 35 ° from the normal to the light emitting surface), significantly improving front brightness and reducing loss of scattered light rays at low exit angles (from the light emitting surface). And the light-condensing

layers

1231 and 1241 are used for enhancing the brightness of light. The material of the light-gathering layer 1231 and the light-gathering layer 1241 may be UV resin, preferably UV acrylic resin, and when the material of the light-gathering layer 1231 and the light-gathering layer 1241 is UV acrylic resin, since the acrylic resin has excellent hardness, the excellent optical performance of the light-gathering layer can be ensured, and the wear resistance of the light-gathering layer 1231 and the light-gathering layer 1241 can also be ensured. Substrate layer 1232 and substrate layer 1242 are located the below of spotlight layer 1231 and spotlight layer 1241 respectively, a below for bearing spotlight layer 1231 and spotlight layer 1241, substrate layer 1232 and substrate layer 1242's material can be in polyethylene terephthalate (PET), Polycarbonate (PC), one kind in polymethyl methacrylate (PMMA), under general conditions, the material of substrate layer 1232 and substrate layer 1242 is polyethylene terephthalate, because it has excellent physical properties and chemical properties, have dimensional stability, the better characteristics of transparency, and impact strength is also higher, be favorable to the substrate layer by excessive wear. The diffusion layer 1243 is generally a coating solution of UV resin, and is uniformly coated (coating) on the lower side of the substrate layer of the lower brightness enhancement film 124, and is formed into the diffusion layer 1243 through UV curing, so as to diffuse light and sufficiently scatter incident light, thereby achieving a softer and more uniform irradiation effect.

Specifically, the micro-prism structure is used for concentrating the dispersed light to emit light within 70 degrees of the normal, and the principle is that the light emitted by more than 70 degrees is reflected back to be utilized again by utilizing the full-emission law, so that the brightness at the center of the axis can be increased by 110 percent, and the principle is that the dispersed light is concentrated to a certain angle and emitted from the backlight source by utilizing the refraction and total reflection principles.

The organic particles 1244 may be added to a coating solution of the UV resin and then uniformly coated under the base layer of the lower brightness enhancement film 124 by coating (coating) to form a diffusion layer. The light is refracted, reflected or scattered by the diffusion layer 1243 added with the organic particles 1244, so that the light is refracted, reflected and scattered in different directions, the traveling route of the light is changed, the incident light is fully dispersed, and a softer and more uniform irradiation effect is realized. The material of the organic particles 1244 may be any one or more of polymethyl methacrylate (PMMA), polybutyl methacrylate (PBMA), Polystyrene (PS), polyamide nylon (PA), silicone resin, and silicone particles. In addition, by adding the organic particles 1244 to the diffusion layer 1243, the wear resistance of the diffusion layer can be improved.

The optical adhesive layer 122 is provided with diffusion particles 1221, and the diffusion particles 1221 are used for diffusing light.

Specifically, the Optical Adhesive layer 122 may be an OCA Adhesive (Optical Clear Adhesive), a transparent Optical Adhesive, with a light transmittance of 90% or more and a good Adhesive strength, which can be cured at room temperature or medium temperature, and is a special Adhesive for bonding transparent Optical elements, and is widely applied in the field of display technology. The light-collecting layer 1231 and the light-collecting layer 1241 corresponding to the upper brightness enhancement film 123 and the lower brightness enhancement film 124 generally adopt an isosceles-triangular long-strip-shaped micro Prism (Prism) structure, and through refraction and total reflection of light rays on the side surfaces of the prisms and multiple refraction among the prisms, an orthographic accumulation effect and a recycling effect of the light rays are generated, so that the control of the emergence angle of most of the light rays is realized. However, due to the ordered array of equally spaced prisms, the prism apex angle is fixed, and in liquid crystal display applications, the ordered array of prisms will overlap the ordered pixels (pixels) of the liquid crystal display, creating interference, i.e., moire fringes, or so-called moire. Therefore, the diffusion particles 1221 need to be added to the optical adhesive layer 122 to scatter incident light at multiple angles, so as to solve the problem of interference between the incident light and the pixels of the liquid crystal display.

Among them, the diffusion particles 1221 include organic diffusion particles and/or inorganic diffusion particles.

Specifically, the diffusion particles 1221 may be inorganic particles, for example, any one or more of silica (SiO2), titanium dioxide (TiO2), alumina (Al2O3), zinc oxide (Al2O3), calcium carbonate (CaCo3), and barium sulfate (BaSO4), and are preferably silica, which functions to diffuse light. The diffusion particles 1221 may also be organic particles 1244, for example, any one or more of polymethyl methacrylate (PMMA), polybutyl methacrylate (PBMA), Polystyrene (PS), polyamide nylon (PA), silicone resin, and silicone particles, preferably polymethyl methacrylate (PMMA).

Taking the display device 100 shown in fig. 1 as an example, by adjusting parameters such as the refractive index, the haze and the thickness of the optical adhesive layer 122, and the doping concentration of the diffusing particles in the optical adhesive layer 122, the brightness, the interference fringes and the bonding strength between the display screen 110 and the optical composite film 121 of the display device 100 are tested, and part of the collected data can be shown in table 1 below:

TABLE 1

Here, the peel force gf/25mm, i.e., the fitting strength, shown in Table 1 means the number of grams of force received per 25mm length, for example, the peel force of the sixth column of the first row of Table 1 is 40gf/25mm, i.e., the number of grams of force received per 25mm length is 40 grams. The brightness shown in table 1 is the ratio of the brightness of the display device 100 tested to the reference of the two single brightness enhancement film structures of the prior art, i.e., the brightness of the two single brightness enhancement film structures is 100%, and the brightness of the display device 100 is, for example, 98% in the first row and the eighth column of table 1.

Specifically, the doping concentration of the diffusion particles 1221 mainly affects the haze of the optical adhesive layer 122, and when the concentration of the diffusion particles 1221 in the optical adhesive layer 122 is higher, the haze of the optical adhesive layer 122 is higher, so that incident light is scattered and transmitted from multiple angles through the diffusion particles 1221, and the problem of interference between the incident light and pixel points of the liquid crystal display screen is solved. Meanwhile, the larger the haze of the optical adhesive layer 122 is, the correspondingly lower the brightness of the light passing through the optical adhesive layer 122, and the influence on the brightness of the display device 100 is, therefore, the concentration of the diffusion particles 1221 should be both improved in terms of interference phenomenon and a certain brightness, and generally, the concentration range of the diffusion particles 1221 is within 20%.

The refractive index range of the optical adhesive layer is 1.38-1.58, and the haze range of the optical adhesive layer is 60-80%.

Specifically, the haze (haze) is the percentage of the total transmitted light intensity of the transmitted light intensity deviating from the incident light by more than 2.5 °, and a larger haze means that the gloss and transparency of the film, especially the imaging degree, are reduced, correspondingly, the brightness of the light after passing through the optical adhesive layer 122 is reduced, and a larger haze effectively improves the interference problem of the pixels of the display screen 110. The refractive index refers to the ratio of the propagation speed of light in a vacuum to the propagation speed of light in the medium. The higher the refractive index of the material is, the stronger the ability of the incident light to refract is, the brighter the incident light penetrates through the optical adhesive layer 122, the front-view brightness is significantly improved, and correspondingly, the better the display effect of the display device 100 is. As shown in table 1, it can be seen from experimental test data that the haze of the optical adhesive layer 122 is preferably in a range of 60% to 80%, and the refractive index of the optical adhesive layer 122 is preferably in a range of 1.38 to 1.58.

The thickness of the optical adhesive layer 122 is 1 to 30 μm.

Specifically, the thickness of the optical adhesive layer 122 affects the peeling force between the optical composite film 121 and the display screen 110, and the larger the peeling force is, the less easily the optical composite adhesive falls off from the display screen 110, and the better the stability is. However, the thickness of the optical adhesive layer 122 cannot be increased endlessly, because the larger the thickness of the optical adhesive layer 122 is, the larger the thickness of the whole display device 100 is correspondingly, and thus the thickness of the optical adhesive layer 122 ranges from 1 to 30 micrometers (um).

As shown in table 1, it can be seen from experimental test data that, preferably, when the refractive index of the optical adhesive layer 122 is 1.58, the thickness is 20 μm, and the haze is 70%, there are no interference fringes and no buckling wrinkle, the brightness is 90% of the prior art, and the adhesive strength of the optical adhesive layer 122 is 1000gf/25mm (i.e., the gram of force per 25mm length is 1000 g). In addition, the refractive index, thickness and haze of the optical adhesive layer 122 may be selected according to practical situations, as long as one or more of the interference fringes, brightness and bonding strength of the display device 100 can be improved, and are not particularly limited.

In the embodiment of the present application, laminate optical composite film 121 and display screen 110 through optical adhesive layer 122, carry out the best design collocation to the haze of optical adhesive layer 122, refracting index and thickness, optimize laminating intensity and reduced the loss of luminance, meanwhile, add diffusion particle 1221 in optical adhesive layer 122, scatter the transmission with the incident light multi-angle, furthermore, optical composite film 121's top and below are equipped with optical adhesive layer 122 and diffusion layer respectively, can realize diffusing light, the poor and easy problem of fold of optical film stiffness has been improved in the embodiment of the present application, meanwhile, for prior art, the embodiment of the present application can not need the diffusion barrier, correspondingly, display device 100's whole thickness has been reduced.

As can be seen from the above, the display device provided in the embodiment of the present invention includes: a display screen; the backlight module is positioned below the display screen, and one side of the backlight module, which is close to the display screen, is provided with an optical composite film; the optical adhesive layer is positioned between the display screen and the optical composite film, the optical composite film and the display screen are laminated through the optical adhesive layer, the diffusion particles are doped in the optical adhesive layer, the matching parameters of the refractive index, the haze and the thickness of the optical adhesive layer are adjusted, the interference phenomenon of pixel points of the display screen is improved on the premise of ensuring certain brightness, meanwhile, the laminating strength of the optical composite film and the display screen is improved, and therefore the quality of the display device is improved.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A display device, comprising:

a display screen;

the backlight module is positioned below the display screen, and an optical composite film is arranged on one side, close to the display screen, of the backlight module;

and the optical adhesive layer is positioned between the display screen and the optical composite film, and the optical composite film is attached to the display screen through the optical adhesive layer.

2. The display device of claim 1, wherein the optical composite film comprises an upper brightness enhancement film and a lower brightness enhancement film disposed in a stack and adhered to one another.

3. The display device of claim 2, wherein the upper and lower brightness enhancement films each comprise a light-concentrating layer and a substrate layer disposed in a stack, and the lower brightness enhancement film further comprises a diffuser layer underlying the substrate layer, the light-concentrating layer comprising at least one micro-prism structure.

4. The display device according to claim 1, wherein diffusion particles are provided in the optical adhesive layer, and the diffusion particles are used for diffusing light.

5. The display device according to claim 4, wherein the diffusion particles include organic diffusion particles and/or inorganic diffusion particles.

6. The display device of claim 4, wherein the diffusion particles have a doping concentration in the optical glue layer of no more than 20%.

7. The display device according to claim 5, wherein a material of the organic diffusion particles includes any one or more of polymethyl methacrylate, polybutyl methacrylate, polystyrene, polyamide nylon, silicone resin, and silicone particles.

8. The display device according to claim 5, wherein a material of the inorganic diffusion particles includes any one or more of silica, titanium dioxide, alumina, zinc oxide, calcium carbonate, and barium sulfate.

9. The display device according to claim 1, wherein the optical adhesive layer has a refractive index ranging from 1.38 to 1.58 and a haze ranging from 60% to 80%.

10. The display device according to claim 1, wherein the optical adhesive layer has a thickness ranging from 1 to 30 μm.