Backlight module and display device

Abstract

The invention provides a backlight module and a display device, the backlight module comprises a light source assembly, and the light source assembly is used for emitting polarized light; the first liquid crystal screen is arranged on the light emitting side of the light source assembly, the first liquid crystal screen comprises a liquid crystal layer and a color filter, the liquid crystal layer is used for controlling the throughput of the polarized light, and the color filter is arranged on the light emitting side of the liquid crystal layer; the color filter comprises a red sub-filter area, a green sub-filter area and a blue sub-filter area to form red light, green light and blue light respectively, and the red light, the green light and the blue light are mixed to form backlight. The backlight module can restrain heat effect interference and eliminate light mixing and color crossing.

Description

Technical Field

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

[0002] In the field of LCD backlight modules, the use of red (R), green (G), and blue (B) LEDs (Light Emitting Diodes) as light sources is widely used due to their wide color gamut coverage and manageable costs. However, due to the limitations of LED device characteristics and the optical design of backlight modules, there are two major technical bottlenecks in actual application: the first is temperature-induced brightness degradation and color shift, and the second is the cross-color problem in mixed-light displays.

[0003] On the one hand, the luminous efficiency and color coordinates of LEDs are highly sensitive to junction temperature. The brightness decay rates of R / G / B tri-color LEDs at high temperatures vary significantly (for example, the red LED decays more rapidly than the green LED), and the color coordinate offset directions are inconsistent, resulting in fluctuations in the color temperature of the mixed white light. In addition, the uneven distribution of heating elements in the backlight module causes temperature differences on the display plane, exacerbating local chromaticity deviations. Existing dynamic compensation solutions rely on high-density temperature sensors and high-computing power chips, but the hardware cost also increases accordingly, and additional compensation chips are required, making it difficult to meet the cost-effectiveness requirements of consumer products.

[0004] Furthermore, due to the discrepancy between LED package size and the sub-pixel size of LCD screens, backlight mixing areas overlap, causing color bleeding between adjacent pixels. When displaying adjacent light and dark images (such as white and red), the light areas are mixed with stray light from other LED colors, reducing color purity and resulting in a subjective visual appearance of color cast. Existing solutions can only partially alleviate this problem through optimized driver algorithms; they cannot fundamentally eliminate cross-color phenomena. Innovation in optical architecture is urgently needed.

[0005] The above problems directly lead to a decrease in display uniformity and distorted color reproduction, becoming a key factor restricting the performance improvement of display products. Summary of the Invention

[0006] The embodiments of the present application provide a backlight module and a display device that can suppress thermal effect interference and eliminate mixed light and color crosstalk.

[0007] The embodiment of the present application provides a backlight module, comprising:

[0008] A light source assembly, the light source assembly being used to emit polarized light;

[0009] A first liquid crystal display screen, which is arranged on the light-emitting side of the light source assembly. The first liquid crystal display screen includes a liquid crystal layer and a color filter. The liquid crystal layer is used to control the passing amount of the polarized light, and the color filter is arranged on the light-emitting side of the liquid crystal layer; the color filter includes a red sub-filter region, a green sub-filter region, and a blue sub-filter region to respectively form red light, green light, and blue light, and the red light, the green light, and the blue light are mixed to form backlight.

[0010] In some embodiments, the light source assembly includes a light-emitting unit and a polarization component. The light-emitting unit is used to emit light source light, and the polarization component is arranged on the light-emitting side of the light-emitting unit. The polarization component is used to convert the light source light into polarized light.

[0011] In some embodiments, the light-emitting unit is a blue light source. The polarization component includes a polarization diffusion layer and a quantum dot layer. The polarization diffusion layer is arranged on the light-emitting side of the light-emitting unit, and the quantum dot layer is arranged on the light-emitting side of the polarization diffusion layer.

[0012] In some embodiments, the light-emitting unit is a miniLED chip; or, the light-emitting unit includes a blue LED and a lens, and the lens is arranged on the blue LED.

[0013] In some embodiments, the light-emitting unit is a blue light source. The polarization component includes a quantum dot polarization diffusion plate, and the quantum dot polarization diffusion plate is arranged on the light-emitting side of the blue light source.

[0014] In some embodiments, the polarization component includes a polarization lens, and the polarization lens is arranged on the light-emitting side of the light-emitting unit.

[0015] In some embodiments, the backlight module further includes a light homogenizing layer, which is arranged between the polarization lens and the first liquid crystal display screen and is used to homogenize the distribution of the polarized light.

[0016] In some embodiments, the red sub-filter region, the green sub-filter region, and the blue sub-filter region are arranged in an array form to form pixel-level partitioned light emission.

[0017] In some embodiments, the backlight module further includes a polarizer, which is arranged on the light-emitting side of the first liquid crystal display screen, and the polarization direction of the polarizer is perpendicular to the polarization direction of the polarized light.

[0018] In some embodiments, the first liquid crystal screen further includes a transparent encapsulation structure and a thin film transistor layer. The liquid crystal layer, the color filter, and the thin film transistor layer are encapsulated within the transparent encapsulation structure. The thin film transistor layer is disposed on a side of the liquid crystal layer away from the color filter, and the thin film transistor layer is configured to drive the liquid crystal layer.

[0019] An embodiment of the present application further provides a display device, including:

[0020] A backlight module, where the backlight module is the above-mentioned backlight module;

[0021] A second liquid crystal screen, where the second liquid crystal screen is disposed on a light-emitting side of the backlight module, and a polarization direction of a polarizer on an incident light side of the second liquid crystal screen is consistent with a polarization direction of polarized light emitted by the backlight module.

[0022] In some embodiments, the red sub-filter region, the green sub-filter region, and the blue sub-filter region are arranged in an array form so that the backlight module has a first resolution; the second liquid crystal screen has a second resolution; the first resolution is less than or equal to the second resolution.

[0023] In the backlight module and the display device provided by the embodiments of the present application, the backlight module includes a light source component and a first liquid crystal screen. The light source component is configured to emit polarized light. The first liquid crystal screen includes a liquid crystal layer and a color filter. The liquid crystal layer is configured to control an amount of polarized light passing through, and the color filter is disposed on a light-emitting side of the liquid crystal layer. The color filter includes a red sub-filter region, a green sub-filter region, and a blue sub-filter region to respectively form red light, green light, and blue light. The red light, the green light, and the blue light are mixed to form backlight. On the one hand, by abandoning the traditional red / green / blue (R / G / B) three-color LED light source and reconstructing the three-color light using the first liquid crystal screen, problems such as brightness attenuation and color shift caused by LED heating are avoided from the root, and the light source stability is significantly improved. On the other hand, in the present application, the liquid crystal layer can perform real-time and precise regulation on the polarized light. Combining with the array layout of the color filter, adjacent three-color lights are pixel-level isolated in space, completely eliminating the color bleeding phenomenon caused by optical path overlap in the traditional solution, and ensuring the accuracy and consistency of color display. Description of the Drawings

[0024] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1The first structural schematic diagram of the backlight module provided by the embodiment of the present application.

[0026] Figure 2 The first structural schematic diagram of the first liquid crystal screen provided by the embodiment of the present application.

[0027] Figure 3 The second structural schematic diagram of the first liquid crystal screen provided by the embodiment of the present application.

[0028] Figure 4 The second structural schematic diagram of the backlight module provided by the embodiment of the present application.

[0029] Figure 5 The third structural schematic diagram of the backlight module provided by the embodiment of the present application.

[0030] Figure 6 The fourth structural schematic diagram of the backlight module provided by the embodiment of the present application.

[0031] Figure 7 The fifth structural schematic diagram of the backlight module provided by the embodiment of the present application.

[0032] Figure 8 The sixth structural schematic diagram of the backlight module provided by the embodiment of the present application.

[0033] Figure 9 The structural schematic diagram of the display device provided by the embodiment of the present application. Detailed implementation manners

[0034] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present application.

[0035] The embodiments of the present application provide a backlight module and a display device, which can suppress the interference of thermal effects and eliminate light mixing and color crosstalk. The following is a specific description in conjunction with the accompanying drawings.

[0036] Please refer to Figure 1 , Figure 1 The first structural schematic diagram of the backlight module provided by the embodiment of the present application.

[0037] An embodiment of the present application provides a backlight module 10. The backlight module 10 is a key component in display devices such as liquid crystal displays (LCDs). Its main function is to provide a uniform and stable light source for the liquid crystal panel, enabling the liquid crystal panel to display images normally. The backlight module 10 is usually composed of components such as a light source, a light guide plate, and optical films. By reasonably combining these components, the light emitted by the light source is shaped, diffused, and homogenized to meet the backlight requirements of the liquid crystal panel. The backlight module 10 provided by the embodiment of the present application can be applied to Local Dimming technology, capable of realizing individual control of each partition, and further realizing dynamic adjustment of the brightness and color of each partition, making the contrast of the picture higher, and the picture clearer and finer.

[0038] The backlight module 10 includes a light source component 11 and a first liquid crystal screen 12.

[0039] The light source component 11 is used to emit polarized light. The polarized light can be better utilized by the first liquid crystal screen 12, reducing unnecessary scattering and reflection.

[0040] Please refer to Figure 1 and Figure 2 , Figure 2 , which is the first structural schematic diagram of the first liquid crystal screen provided by the embodiment of the present application. The first liquid crystal screen 12 is disposed on the light-emitting side of the light source component 11. The first liquid crystal screen 12 includes a liquid crystal layer 121 and a color filter 122. The liquid crystal layer 121 is used to control the passing amount of polarized light. The color filter 122 is disposed on the light-emitting side of the liquid crystal layer 121. The liquid crystal layer 121 is the core control part of the first liquid crystal screen 12, and utilizes the special physical properties of liquid crystal molecules under the action of an electric field to control the passing amount of polarized light. When different electric fields are applied on both sides of the liquid crystal layer 121, the arrangement direction of the liquid crystal molecules will change, thereby changing the polarization state of the light passing through the liquid crystal layer 121. The intensity of polarized light is related to the angle between the polarization direction and the light-transmitting axis of the polarizer. By precisely controlling the arrangement of liquid crystal molecules, the passing amount of polarized light can be precisely controlled.

[0041] Please continue to refer to Figure 2 , the color filter 122 includes a red sub-filter region 1221, a green sub-filter region 1222, and a blue sub-filter region 1223 to respectively form red light, green light, and blue light, and the red light, green light, and blue light are mixed to form backlight.

[0042] Specifically, red sub-filter region 1221 allows only red light within a specific wavelength range to pass through, green sub-filter region 1222 allows only green light to pass through, and blue sub-filter region 1223 allows only blue light to pass through. After polarized light passes through liquid crystal layer 121 and then through color filter 122, the different colored sub-filter regions filter out corresponding red, green, and blue light, respectively. These three basic colors of light, when mixed in a specific intensity ratio, can form a backlight with various colors and intensities, creating a zoned display.

[0043] The red sub-filter region 1221, the green sub-filter region 1222, and the blue sub-filter region 1223 are arranged in an array to form pixel-level zoned illumination. Array arrangement refers to the orderly arrangement of multiple identical or different elements in regular rows and columns. Pixel-level zoned illumination refers to dividing the display into independent pixel units, each of which can independently emit light or control the intensity and color of light.

[0044] Specifically, the red sub-filter region 1221, the green sub-filter region 1222, and the blue sub-filter region 1223 can be neatly arranged according to a strict number of rows and columns, forming a regular grid structure. Each intersection corresponds to a pixel unit, and each pixel unit is composed of a red sub-filter region 1221, a green sub-filter region 1222, and a blue sub-filter region 1223. This arrangement achieves pixel-level zoned illumination.

[0045] Taking the display of a high-definition image as an example, every detail in the image corresponds to a pixel unit. During the display process, the system will accurately control the amount of light passing through the red sub-filter area 1221, the green sub-filter area 1222, and the blue sub-filter area 1223 in the corresponding pixel unit based on the color information of each pixel in the image. For example, when a red pixel needs to be displayed, the system will increase the amount of light passing through the red sub-filter area 1221, while reducing the amount of light passing through the green sub-filter area 1222 and the blue sub-filter area 1223, so that the pixel appears red. Through this pixel-level partitioned light emission method, a red backlight is formed, thereby realizing backlight partitioning.

[0046] Thus, in the embodiment of the present application, the backlight module 10 can be divided into multiple independent areas, and the brightness of each area can be independently adjusted according to the content of the picture. When the first LCD screen 12 can adjust the brightness and even the color of each area, the bright parts of the picture are brighter and the dark parts are darker, thereby greatly improving the contrast and layering of the picture, giving the audience a more realistic and shocking visual experience.

[0047] Compared with ordinary multi-zone RGB backlights, the number of zones in the embodiments of the present application has significant advantages. The number of zones in ordinary RGB backlights is only dozens or hundreds, while the present application can reach several times or even dozens of times that number. More zones can more precisely correspond to the picture area, enabling more delicate adjustment of brightness and color. When displaying complex pictures, it can better adapt to brightness changes, avoid local overbrightness or overdarkness, and make the picture more uniform and natural.

[0048] Ordinary RGB backlights are prone to brightness attenuation and color deviation due to the aging of the light-emitting units 111, and algorithm compensation is required. By virtue of precise zone control and pixel-level color adjustment, the embodiments of the present application can adjust brightness and color in real time without algorithm compensation, reducing the error accumulation caused by algorithm compensation.

[0049] Among them, please refer to Figure 3 , Figure 3 which is the second structural schematic diagram of the first liquid crystal screen provided by the embodiments of the present application. The backlight module 10 further includes a polarizer 14, and the polarizer 14 is disposed on the light-emitting side of the first liquid crystal screen 12. The polarization direction of the polarizer 14 is perpendicular to the polarization direction of the polarized light. The polarizer 14 is an optical element that can selectively transmit light with a specific polarization direction. The polarizer 14 is made of a dichroic material, which only allows light with the same polarization direction as itself to pass through, while absorbing or blocking light with other polarization directions. In display technology, the polarizer 14 is commonly used to control the polarization state of light, realizing the modulation of light and the optimization of the display effect.

[0050] When the polarized light exits from the first liquid crystal screen 12, only the light component with the same polarization direction as the polarizer 14 can pass through the polarizer 14, while the light components with other polarization directions will be absorbed or blocked. This design can further improve the light utilization efficiency and the contrast of the display picture. For example, when displaying a black picture, through the action of the polarizer 14, the interference of stray light can be effectively reduced, making the black area purer, thereby enhancing the overall contrast of the picture.

[0051] Please continue to refer to Figure 3 , the first liquid crystal screen 12 further includes a transparent encapsulation structure 124 and a thin-film transistor layer 123.

[0052] The liquid crystal layer 121, the color filter 122, and the thin-film transistor layer 123 are encapsulated within the transparent encapsulation structure 124. The transparent encapsulation structure 124 can prevent external environmental factors (such as dust, moisture, etc.) from damaging the internal components, while ensuring that light can propagate normally between these components.

[0053] The transparent encapsulation structure 124 includes a first transparent encapsulation layer and a second transparent encapsulation layer, which are respectively disposed on both sides of the liquid crystal layer 121, the color filter 122, and the thin film transistor layer 123. The first transparent encapsulation layer and the second transparent encapsulation layer are closely attached to form a sealed space that completely wraps the internal components. This double-layer encapsulation design not only enhances the mechanical strength of the transparent encapsulation structure 124, improves its impact resistance and abrasion resistance, but also further improves the sealing performance, effectively preventing the intrusion of external substances.

[0054] The thin film transistor layer 123 is disposed on the side of the liquid crystal layer 121 away from the color filter 122, and the thin film transistor layer 123 is used to drive the liquid crystal layer 121. In the first liquid crystal screen 12, the thin film transistor layer 123 receives electrical signals from the display driving circuit and controls the arrangement state of the liquid crystal molecules corresponding to each pixel point in the liquid crystal layer 121 according to these signals, so as to achieve precise control of the light passing amount, and further achieve the regulation of the color and brightness of the light, and further achieve backlight zoning.

[0055] That is to say, the backlight module 10 is divided into multiple independent areas, and the brightness of each area can be independently adjusted according to the picture content. After the first liquid crystal screen 12 precisely regulates the light in a certain area, the backlight module 10 can correspondingly adjust the brightness of this area, making the bright parts in the picture brighter and the dark parts darker, thereby greatly improving the contrast and layering of the picture and bringing a more realistic and shocking visual experience to the audience.

[0056] Please refer to Figure 4 , Figure 4 which is the second structural schematic diagram of the backlight module provided by the embodiment of the present application. The light source assembly 11 includes a light emitting unit 111 and a polarization assembly 112, and the light emitting unit 111 is used to emit light source light. The light emitting unit 111 efficiently converts the input electrical energy into light energy through an internal physical mechanism and emits the light source light. The light emitting unit 111 can be a common LED lamp or a miniLED (Mini Light Emitting Diode) chip, etc. For example, in an LED lamp, when an electric current passes through a semiconductor material, electrons and holes recombine, releasing energy and radiating in the form of photons, thereby generating light. This light source light is natural light in its initial state, and the vibration direction of its light wave is randomly distributed in a plane perpendicular to the propagation direction and does not have a specific polarization characteristic.

[0057] The polarization component 112 is disposed on the light-emitting side of the light-emitting unit 111. The polarization component 112 is used to convert the light from the light source into polarized light. The polarization component 112 has a special optical structure that can selectively transmit or absorb light of a specific polarization direction. When the light from the light source passes through the polarization component 112, only the light component with the same polarization direction as that of the polarization component 112 can pass through, while the light components of other polarization directions are absorbed or blocked, thereby converting the light from the light source into polarized light.

[0058] Taking a liquid crystal display as an example, the polarized light processed by the polarization component 112 enters the liquid crystal layer 121. The liquid crystal molecules will change their alignment under the action of an electric field, thereby changing the polarization state of the polarized light. Then, different colors of light are screened out through the color filter 122, and finally backlight zoning is achieved. If the light from the light source directly enters the liquid crystal layer 121 without being processed by the polarization component 112, due to the randomness of the light polarization direction, it cannot be effectively modulated by the liquid crystal molecules, resulting in problems such as a blurred display image and low contrast. Therefore, the polarization component 112 plays a crucial role in the light source component 11, providing the necessary polarized light conditions for subsequent optical modulation and image display.

[0059] The backlight module 10 further includes a backplane 15, and the backplane 15 has a reflection cavity. The light-emitting unit 111 in the light source component 11 is disposed in the reflection cavity, and a reflector is attached to the inner wall of the reflection cavity.

[0060] The backplane 15 is usually made of a material with high strength, high temperature resistance, and certain rigidity, such as a metal material (such as aluminum alloy), to ensure that it can withstand the weight of the internal components and the possible mechanical stress during the operation of the backlight module 10, while ensuring the structural stability and avoiding affecting the optical performance due to deformation.

[0061] The light-emitting unit 111 in the light source component 11 is accurately disposed in the reflection cavity. The installation position and spacing of the light-emitting unit 111 are accurately calculated to ensure that the light can be evenly distributed in the backlight module 10. During the installation process, a specific fixing method is adopted, such as welding, bonding, or using a special fixing bracket, to firmly fix the light-emitting unit 111 at the bottom of the reflection cavity.

[0062] A reflector is attached to the inner wall of the reflection cavity. The reflector has a high reflectivity and can effectively reflect the light emitted by the light-emitting unit 111 to the polarization component 112, reducing the absorption and loss of light in the reflection cavity.

[0063] The following provides multiple embodiments to specifically illustrate the structural composition of the light source component 11.

[0064] Please continue to refer to Figure 4, The first embodiment of the light source assembly 11: The light emitting unit 111 is a blue light source, and the polarization component 112 includes a polarization diffusion layer 1121 and a quantum dot layer 1122. The polarization diffusion layer 1121 is disposed on the light emitting side of the light emitting unit 111, and the quantum dot layer 1122 is disposed on the light emitting side of the polarization diffusion layer 1121.

[0065] The polarization diffusion layer 1121 can be made of PMMA (Polymethyl Methacrylate), which has the advantages of high transparency, good processability, and certain mechanical strength. At the same time, nanoparticles with birefringence properties, such as titanium dioxide (TiO2), zinc oxide (ZnO), silicon nanoparticles (SiO2), etc., are doped into the PMMA material. The birefringence property means that the refractive index of the material for light is different in different directions, which enables the doped PMMA material to affect the polarization state and propagation direction of light. For the doped PMMA material, it can also be processed by applying external stress, mechanical stretching, etc. to enhance the polarization characteristics.

[0066] For example, when the light from the light source passes through the polarization diffusion layer 1121, the light will undergo scattering and polarization modulation. The scattering effect can make the light more evenly distributed, avoiding local over-bright or over-dark situations; while the polarization modulation will make some light obtain a specific polarization direction, preparing for subsequent optical processing (entering the first liquid crystal screen 12).

[0067] Specifically, the principle of polarization modulation of the polarization diffusion layer 1121 mainly includes two aspects: polarization separation caused by doping birefringent nanoparticles, and change of polarization characteristics caused by external stress or mechanical stretching to change the material structure.

[0068] In terms of polarization separation caused by doping birefringent nanoparticles, when nanoparticles with birefringence properties such as titanium dioxide (TiO2), zinc oxide (ZnO), silicon nanoparticles (SiO2), etc. are doped into the PMMA material, it will make the material have anisotropy of refractive index, that is, the refractive index of light is different in different directions. After natural light is incident, according to the Huygens - Fresnel principle, it is decomposed into ordinary light (o - light) and extraordinary light (e - light) with perpendicular polarization directions. The vibration direction of o - light is perpendicular to the plane formed by the light propagation direction and the optical axis of the material, and it follows the refraction law; the vibration direction of e - light is in the above - mentioned plane and does not follow the refraction law. At the same time, the scattering and absorption of light with different polarization directions by the nanoparticles are different, resulting in large propagation loss of light in one polarization direction and relatively easy transmission in the other direction. The intensity of the light in this polarization direction in the emitted light is enhanced, realizing selective transmission of polarized light and strengthening the polarization characteristics.

[0069] In terms of changing the material structure by applying external stress or mechanical stretching, when stress or stretching is applied to the doped PMMA material, its internal microstructure will change, the arrangement pattern and spacing of nanoparticles in the PMMA matrix will change, and the optical anisotropy will be enhanced. For example, stress may cause the nanoparticles to be arranged orderly along a specific direction, thereby changing the optical axis direction and birefringence characteristics of the material. By reasonably controlling the degree and direction of stress or stretching, the polarization characteristics of the material can be precisely regulated, such as maximizing the light intensity of a certain polarization direction in the outgoing light, or causing a specific rotation of the polarization direction of polarized light, to achieve the generation and regulation of polarized light.

[0070] It can be understood that doping with birefringent nanoparticles can already endow the outgoing light with polarization characteristics, and applying external stress or mechanical stretching to change the material structure will further enhance the polarization effect.

[0071] The quantum dot layer 1122 uses a PET (Polyethylene Terephthalate) substrate doped with quantum dot materials. The quantum dot layer 1122 is used to convert part of the blue polarized light into red polarized light and green polarized light, and the blue polarized light, red polarized light, and green polarized light are mixed to form white polarized light. Quantum dots, as nanoscale semiconductor materials, have unique quantum confinement effects. Their sizes are usually between a few nanometers and dozens of nanometers. Quantum dots of different sizes have different energy band structures, which enables them to absorb light of specific wavelengths and emit light of different colors. For example, quantum dots with smaller sizes may absorb blue light and emit green light, while quantum dots with slightly larger sizes may absorb blue light and emit red light.

[0072] Please continue to refer to Figure 4 , the second embodiment of the light source assembly 11: On the basis of the first embodiment of the light source assembly 11, the quantum dot layer 1122 can also be a polarization quantum dot layer, that is, the quantum dot layer 1122 also has the function of maintaining polarization. This means that during the light color conversion process, the polarization state of light can be kept unchanged. This characteristic is crucial for improving the contrast and color purity of display devices. Specifically, lithium niobate (LiNbO3) nanoparticles, titanium dioxide (TiO2) nanoparticles, etc. are doped in the substrate of the quantum dot layer 1122. These nanoparticles have unique optical properties and can interact with light to achieve the protection of the polarization state of light. For example, lithium niobate nanoparticles have an electro-optic effect. When an electric field is applied, its refractive index will change, and this characteristic can be used to adjust the propagation direction and polarization state of light. Titanium dioxide nanoparticles have a high refractive index and good scattering properties, and can scatter and modulate the polarization of light, enhancing the polarization-maintaining ability of the quantum dot layer 1122.

[0073] The nanoparticles in this application are only for illustration. The specific choice of nanoparticles depends on application requirements (such as optical properties, transparency, processability, etc.) and the required polarization strength of the overall backlight module 10.

[0074] Please refer to Figure 5 , Figure 5 which is the third structural schematic diagram of the backlight module provided by the embodiment of this application.

[0075] The third embodiment of the light source component 11: The light emitting unit 111 is a blue light source, and the polarization component 112 includes a quantum dot polarization diffusion plate 1123, and the quantum dot polarization diffusion plate 1123 is arranged on the light emitting side of the blue light source.

[0076] The quantum dot polarization diffusion plate 1123 not only has the function of light color conversion, but also has the polarization function and the diffusion function.

[0077] The quantum dot polarization diffusion plate 1123 is doped with quantum dot materials. The quantum dot materials are the same as those in the above embodiments and will not be elaborated here.

[0078] Similarly, the quantum dot polarization diffusion plate 1123 is processed by external stress, mechanical stretching, etc. to make it have polarization characteristics.

[0079] The quantum dot polarization diffusion plate 1123 also has the diffusion function because it is doped with nanoparticles. When light enters the diffusion plate, scattering will occur on the surface of the nanoparticles. The nanoparticles are the same as those in the above embodiments and will not be elaborated here.

[0080] It can be understood that, in order to reduce the thickness, the quantum dot diffusion plate in the embodiment of this application can be regarded as doping the polarization diffusion layer 1121 in the above embodiment with quantum dot materials to make it have multiple functions. In traditional display systems, different optical elements, such as quantum dot films, polarizers, and diffusion plates, are usually required to achieve color conversion, polarization, and diffusion functions respectively, which will lead to complex structures and increased costs. The quantum dot polarization diffusion plate 1123 integrates the three functions into one element, reducing the number of elements and assembly complexity, and lowering the cost. At the same time, the synergistic effect between the functions can better optimize the color, polarization, and distribution characteristics of light, improving the color reproduction, contrast, and uniformity of the display screen.

[0081] In the embodiment of the light source component 11, when the light emitting unit 111 is a blue light source, the light emitting unit 111 can be a miniLED chip or a combination of a common LED and a lens.

[0082] The miniLED chips are relatively small, generally ranging from dozens of micrometers to hundreds of micrometers. This small size enables more chips to be integrated on the second liquid crystal screen of the same area, offering advantages such as small size, high brightness, and high contrast, resulting in a clearer and more delicate display effect.

[0083] Please refer to Figure 6 , Figure 6 which is the fourth schematic structural diagram of the backlight module provided by the embodiment of the present application. In the combination form of a general LED and a lens, the general LED is a blue LED 1111, and the lens 1112 is disposed on the blue LED 1111. The lens 1112 mainly plays a role in optical path regulation. The lens 1112 is usually made of an optical-grade material, such as glass or plastic, and its surface is specially optically designed to refract, reflect, etc. the light emitted by the LED, changing the propagation direction and distribution range of the light. Compared with the miniLED chip, the combination form of the general LED and the lens has the characteristics of low cost and flexible optical path regulation.

[0084] Please refer to Figure 7 , Figure 7 which is the fifth schematic structural diagram of the backlight module provided by the embodiment of the present application.

[0085] The fourth embodiment of the light source assembly 11: In order to greatly reduce costs, the light-emitting unit 111 can be a white LED 1113 and the lens 1112, and the lens 1112 is disposed on the white LED 1113; the polarization component 112 can be a polarization diffusion layer 1121. Specifically, the white light emitted from the light-emitting unit 111 is subjected to the optical path regulation of the lens 1112 and then further enters the polarization diffusion layer 1121, where scattering and polarization modulation occur, thereby forming polarized light. The polarization diffusion layer 1121 in this embodiment is consistent with the polarization diffusion layer 1121 in the above embodiment in terms of function and material, both having the functions of scattering and polarization modulation, and will not be elaborated here.

[0086] Please refer to Figure 8 , Figure 8 which is the sixth schematic structural diagram of the backlight module provided by the embodiment of the present application.

[0087] The fifth embodiment of the light source assembly 11: The polarization component 112 includes a polarization lens 1124, and the polarization lens 1124 is disposed on the light-emitting side of the light-emitting unit 111. The polarization lens 1124 can be made of a material of PMMA (polymethyl methacrylate) doped with nanoparticles having birefringence characteristics. PMMA has good optical transparency, mechanical properties and processing properties, and is a commonly used optical material. Birefringence means that the material has different refractive indices for light with different polarization directions. By reasonably designing the type, size and distribution of the nanoparticles, the polarization lens 1124 can selectively transmit or focus light with a specific polarization direction, thereby realizing the polarization function. The doped birefringent nanoparticles endow the lens with special polarization functions. The nanoparticles are consistent with the nanoparticles in the above embodiments in terms of function and material, and will not be elaborated here.

[0088] Therefore, based on the principle of optical refraction, the surface of the polarization lens 1124 usually has a specific curvature or optical structure. When light is incident on the polarization lens 1124, refraction occurs on the lens surface, which has the effect of optical path regulation. The polarization lens 1124 can also adjust the light into polarized light.

[0089] Among them, the backlight module 10 further includes a light homogenizing layer 13, and the light homogenizing layer 13 is disposed between the polarization lens 1124 and the first liquid crystal screen 12 for homogenizing the distribution of polarized light. The polarized light emitted from the polarization lens 1124 may have problems such as uneven intensity and inconsistent direction. The light homogenizing layer 13 makes the light more evenly distributed in space through the scattering and refraction of light, avoiding the phenomenon of local overbrightness or overdarkness, and improving the brightness and color uniformity of the display screen.

[0090] The light homogenizing layer 13 can also have polarization-preserving characteristics. Specifically, the light homogenizing layer 13 can be a PMMA layer doped with nanoparticles having birefringence characteristics to achieve polarization-preserving characteristics. The birefringence effect of the nanoparticles enables the light homogenizing layer 13 to keep the polarization state of the light unchanged while homogenizing the light. The light homogenizing layer 13 can also use materials such as polyimide (PI) and triacetyl cellulose (TAC) to achieve polarization-preserving characteristics. Materials such as polyimide and triacetyl cellulose itself have certain optical anisotropy and can maintain the polarization state of light to a certain extent.

[0091] In the fifth embodiment of the light source assembly 11, in some cases, the light-emitting unit 111 is a white light-emitting unit 111. Through the action of the polarization lens 1124, the light source assembly 11 emits white polarized light for use by the subsequent first liquid crystal screen 12.

[0092] In the fifth embodiment of the light source assembly 11, in some other cases, when the light emitting unit 111 is blue light, quantum dot materials can also be provided in the polarization lens 1124 to convert part of the blue light into red light and green light, and then mix them to form white polarized light, which is used by the subsequent first liquid crystal screen 12.

[0093] Please refer to Figure 9 , Figure 9 which is a schematic structural diagram of the display device provided by the embodiment of the present application.

[0094] The embodiment of the present application also provides a display device. The display device provided by the embodiment of the present application has wide applicability and can be applied to various product forms such as televisions, monitors, tablets, or advertising curtain walls.

[0095] The display device includes a backlight module 10 and a second liquid crystal screen. The backlight module 10 can be the backlight module 10 in the above embodiment, providing necessary light for the second liquid crystal screen and forming zoned backlight. The second liquid crystal screen is arranged on the light-emitting side of the backlight module 10 to further modulate the light to present the final image. The two work together to jointly realize the display function.

[0096] The polarization direction of the polarizer on the light-incident side of the second liquid crystal screen is consistent with the polarization direction of the polarized light emitted by the backlight module 10. In the optical principle, when the polarization direction of the incident light is consistent with the transmission axis direction of the polarizer, the light can pass through the polarizer smoothly; if the two directions are inconsistent, the light will be largely absorbed or reflected, resulting in light loss. By making the two polarization directions consistent, it can be ensured that the polarized light emitted by the backlight module 10 passes through the polarizer on the light-incident side of the second liquid crystal screen to the greatest extent, greatly reducing light loss, improving the utilization rate of light, and thus enhancing the brightness and energy efficiency of the display device.

[0097] The backlight module 10 can be divided into multiple independent regions, and the brightness of each region can be independently adjusted according to the picture content displayed on the second liquid crystal screen. The RGB three-color light emitted by the first liquid crystal screen 12 is the backlight used for the display screen, realizing RGB three-color light at the pixel level. Compared with ordinary multi-zoned RGB backlight, the embodiment of the present application can provide a number of zones far exceeding that of ordinary RGB backlight. More zones mean that different regions in the picture can be more precisely corresponded to, realizing more delicate adjustment of brightness and color. For example, ordinary RGB backlight may have only dozens or hundreds of zones, while the number of zones of the backlight module 10 in the present application may be several times or even dozens of times that of it.

[0098] When displaying a complex picture, more zones can better adapt to the brightness changes in different regions of the picture, avoiding local over-brightness or over-darkness, and making the picture more uniform and natural.

[0099] During the use of a common RGB backlight, due to reasons such as the aging of the light-emitting unit 111, problems such as brightness attenuation and color deviation may occur, which need to be compensated by algorithms. However, in the embodiments of the present application, through precise zoning control and pixel-level color adjustment, the brightness and color can be adjusted in real time without relying on algorithm compensation, avoiding the errors and instabilities that may be brought by algorithm compensation.

[0100] Among them, the red sub-filter region 1221, the green sub-filter region 1222, and the blue sub-filter region 1223 in the first liquid crystal screen 12 are arranged in an array form so that the backlight module 10 has a first resolution. For example, in a simple array, the red, green, and blue sub-filter regions may be arranged in the order of RGBRGB... in turn, forming a periodic color distribution.

[0101] The first resolution of the backlight module 10 is jointly determined by the arrangement density and distribution mode of the red, green, and blue sub-filter regions. The first resolution intuitively reflects the fineness of the first liquid crystal screen 12 in color control. Specifically, it is the number of regions that can independently control colors per unit area.

[0102] The second liquid crystal screen has a second resolution. The second resolution of the second liquid crystal screen is the pixel resolution inherent in the second liquid crystal screen itself, which determines the detail level of the image that the second liquid crystal screen can display, that is, the number of pixel points per unit area.

[0103] The first resolution is less than or equal to the second resolution. For example, the red, green, and blue sub-filter regions of the backlight module 10 are arranged at a density of 200 groups per inch (first resolution), while the pixel density of the second liquid crystal screen is 400 pixels per inch (second resolution). This indicates that the fineness of the first liquid crystal screen 12 in color control may be slightly lower than the fineness of the second liquid crystal screen in image detail display. Although this resolution difference will cause a slight reduction in the picture quality effect, compared with the common multi-zone RGB scheme, the picture quality of the embodiments of the present application is still far superior.

[0104] For example, in the common multi-zone RGB scheme, due to factors such as a small number of partitions and inaccurate color control, obvious problems such as color deviation, color bleeding, and low contrast often occur in the picture. However, in the embodiments of the present application, through the carefully designed arrangement of the filter array and the reasonable resolution setting, while ensuring a certain picture quality level, the cost is effectively controlled.

[0105] In the above embodiments, the descriptions of the respective embodiments have their own emphases. For parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0106] In the description of the present application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features.

[0107] The above has introduced in detail the backlight module and the display device provided by the embodiments of the present application. Specific examples are used herein to illustrate the principle and implementation manner of the present application. The description of the above embodiments is only for helping to understand the present application. At the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A backlight module, characterized in that, Comprising: A light source assembly for emitting polarized light. A first liquid crystal display screen disposed on the light-emitting side of the light source assembly. The first liquid crystal display screen includes a liquid crystal layer and a color filter. The liquid crystal layer is used to control the passing amount of the polarized light, and the color filter is disposed on the light-emitting side of the liquid crystal layer. The color filter includes a red sub-filter region, a green sub-filter region, and a blue sub-filter region to respectively form red light, green light, and blue light, and the red light, the green light, and the blue light are mixed to form backlight.

2. The backlight module according to claim 1, wherein The light source assembly includes a light-emitting unit for emitting light source light, and a polarization component disposed on the light-emitting side of the light-emitting unit for converting the light source light into polarized light.

3. The backlight module according to claim 2, wherein The light-emitting unit is a blue light source. The polarization component includes a polarization diffusion layer and a quantum dot layer. The polarization diffusion layer is disposed on the light-emitting side of the light-emitting unit, and the quantum dot layer is disposed on the light-emitting side of the polarization diffusion layer.

4. The backlight module according to claim 3, wherein, The light-emitting unit is a miniLED chip; or the light-emitting unit includes a blue LED and a lens disposed on the blue LED.

5. The backlight module according to claim 2, characterized in that, The light-emitting unit is a blue light source. The polarization component includes a quantum dot polarization diffusion plate disposed on the light-emitting side of the blue light source.

6. The backlight module according to claim 2, wherein, The polarization component includes a polarization lens disposed on the light-emitting side of the light-emitting unit.

7. The backlight module according to claim 6, characterized in that, It further includes a light homogenizing layer disposed between the polarization lens and the first liquid crystal display screen for homogenizing the distribution of the polarized light.

8. The backlight module according to any one of claims 1 to 7, characterized in that, The red sub-filter region, the green sub-filter region, and the blue sub-filter region are arranged in an array form to form pixel-level partitioned light emission.

9. The backlight module according to any one of claims 1 to 7, characterized in that, It further includes a polarizer disposed on the light-emitting side of the first liquid crystal display screen, and the polarization direction of the polarizer is perpendicular to the polarization direction of the polarized light.

10. The backlight module according to any one of claims 1 to 7, characterized in that, The first liquid crystal display screen further includes a transparent encapsulation structure and a thin film transistor layer. The liquid crystal layer, the color filter, and the thin film transistor layer are encapsulated in the transparent encapsulation structure. The thin film transistor layer is disposed on the side of the liquid crystal layer away from the color filter, and the thin film transistor layer is used to drive the liquid crystal layer.

11. A display device, characterized in that, Comprising: A backlight module, which is the backlight module according to any one of claims 1 to 10. A second liquid crystal display screen disposed on the light-emitting side of the backlight module, and the polarization direction of the polarizer on the light-incident side of the second liquid crystal display screen is consistent with the polarization direction of the polarized light emitted by the backlight module.

12. The display device according to claim 11, wherein The red sub-filter region, the green sub-filter region, and the blue sub-filter region are arranged in an array form such that the backlight module has a first resolution; the second liquid crystal display screen has a second resolution; the first resolution is less than or equal to the second resolution.

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