Low-power-consumption LED backlight source containing nano scattering particles and preparation method of low-power-consumption LED backlight source

Abstract

The invention belongs to the technical field of photoelectric display devices, and particularly relates to a low-power-consumption LED backlight source containing nano scattering particles and a preparation method thereof.The low-power-consumption LED backlight source comprises an LED light source array which comprises a plurality of light emitting diode chips and is arranged on the side edge or the bottom of a light guide plate, the light emitting diode chips are electrically connected with a driving circuit board, and the driving circuit board is electrically connected with the LED light source array; the driving circuit board provides driving current to enable the LED light source array to emit light, and the LED light source array emits light in the form of a point light source or a line light source and couples the light into the light guide plate; and the reflecting layer is arranged below the LED light source array or on the bottom surface of the light guide plate and is made of a high-reflectivity material, and the material comprises but is not limited to a high-reflectivity polymer diaphragm or a multilayer dielectric film stack. By adopting the nano scattering particle layer of which the thickness is obviously reduced, the propagation path of light rays in the diffusion layer is effectively shortened, so that the internal absorption loss of the light rays is greatly reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of optoelectronic display devices, and particularly relates to a low-power-consumption LED backlight source containing nano scattering particles and a preparation method thereof. BACKGROUND

[0002] Liquid crystal display technology has occupied a dominant position in many fields such as consumer electronics, industrial control and medical display due to its excellent display performance and wide applicability. In a liquid crystal display module, the backlight source as a core component directly determines the brightness, uniformity, color performance and energy efficiency of the display. With the continuous improvement of consumers' requirements for display product image quality and the increasing demand for portability and long endurance, LED backlight source technology with high luminous efficiency, excellent optical uniformity and low power consumption has become the focus of industry's continuous research and development. The current technology development trend especially emphasizes reducing power consumption to the maximum extent while ensuring display performance to meet the requirements of green environmental protection and energy saving.

[0003] The existing mainstream LED backlight source, whether it is a direct type or a side-in type structure, usually contains an LED light source, a light guide plate (for the side-in type), a reflection layer and an optical film set. Among them, the key role of the optical film set is to effectively shape and diffuse the light emitted by the LED light source to achieve screen brightness uniformity and improve overall optical efficiency. Specifically, the diffusion plate (or diffusion sheet) is an indispensable layer in the optical film set, and its main function is to convert point light sources or linear light sources into area light sources through light scattering, thereby eliminating the "hot spots" generated by LED lamp beads and improving the brightness uniformity of the entire display area. The traditional diffusion plate is usually composed of a polymer substrate and contains a certain concentration and size of scattering particles. These scattering particles realize wide-angle diffusion of light beams through refraction, reflection and diffraction interactions with light. Correspondingly, the reflection layer is used to recover and guide the light that is not emitted in the direction of the screen to improve the utilization rate of light. On this basis, other functional film layers such as prism sheets and brightness enhancement films further optimize the light emitting angle and brightness.

[0004] However, with the continuous development of related technologies and the increasingly stringent requirements of application scenarios on performance indicators, the diffusion technology based on the bulk scattering principle commonly used in the traditional LED backlight source has some inherent characteristics at the principle level, which gradually shows limitations in dealing with new challenges such as low power consumption, high uniformity, and ultra-thin. The reason is that, in order to achieve the required brightness uniformity, the traditional diffusion plate often needs a high concentration of scattering particles or a certain thickness. Although a high concentration of scattering particles can effectively enhance the diffusion effect, it will also significantly increase the multiple scattering and absorption loss of light inside the diffusion layer, resulting in a decrease in light exit rate, and thus weakening the overall optical efficiency of the backlight source. In other words, in order to maintain the required brightness of the screen, the driving current of the LED has to be increased, thereby directly increasing the power consumption, which is in sharp contrast to the pursuit of "low power consumption" by modern display devices. Furthermore, if the diffusion effect is attempted to be improved by increasing the thickness of the diffusion plate, the lightness and thinness characteristics of the display module will be directly sacrificed, which is contrary to the general demand for "ultra-thin" design of current consumer electronics products. In addition, the size and distribution of traditional scattering particles are difficult to achieve fine regulation of the light propagation path, so that part of the scattered light cannot be effectively emitted towards the display area, but is reflected back to the interior of the backlight source or absorbed by other components, further exacerbating the waste of light energy. The inherent limitations of this bulk scattering principle make it difficult for the traditional diffusion technology to balance high optical efficiency and ultra-thin design goals while pursuing excellent light uniformity. Especially in the face of increasingly stringent brightness uniformity indicators for large-size, high-resolution display panels, the inherent defects of the traditional scheme will make it increasingly difficult to choose between power consumption and performance. Therefore, the present application provides a low-power-consumption LED backlight source containing nano-scattering particles and a preparation method thereof. SUMMARY

[0005] In order to make up for the deficiencies of the prior art and solve at least one technical problem raised in the background art.

[0006] The technical scheme adopted by the present application to solve its technical problems is: a low-power-consumption LED backlight source containing nano-scattering particles, comprising: an LED light source array; a reflection layer; a light guide plate; a nano-scattering particle layer; and an optical film group.

[0007] The LED light source array comprises a plurality of light-emitting diode chips arranged on the side or bottom of the light guide plate. The light-emitting diode chips are connected to the driving circuit board through electrical connection and are provided with driving current by the driving circuit board to emit light. The light-emitting diode chips are white light-emitting diodes or a combination of multi-color light-emitting diodes, whose light-emitting wavelengths cover the visible light spectrum range. The LED light source array emits light in the form of a point light source or a line light source and couples it into the light guide plate or directly emits it.

[0008] A reflective layer is disposed below the LED light source array or on the bottom surface of the light guide plate. The reflective layer is made of a material with high reflectivity and is used to reflect light that is not emitted along the display direction back into the backlight, thereby improving light utilization efficiency. The reflective layer includes, but is not limited to, a silver (Ag) or aluminum (Al) thin film deposited on a polyethylene terephthalate (PET) substrate by vacuum sputtering or evaporation processes, covered with a silicon oxide (SiO2) or silicon nitride (SiN) protective layer to prevent oxidation; or it can be formed by stacking multiple dielectric thin films, consisting of alternating layers of high-refractive-index material (e.g., titanium dioxide TiO2) and low-refractive-index material (e.g., silicon dioxide SiO2), with the film thickness precisely designed to achieve an average reflectivity of over 98% in the visible spectrum. The reflective layer is laminated to the light guide plate using optical adhesive or tightly bonded by mechanical pressing. The reflective surface of the reflective layer faces the light guide plate and the nano-scattering particle layer.

[0009] A light guide plate is disposed above or closely attached to the reflective layer. The light guide plate is integrally molded from optical-grade polymethyl methacrylate (PMMA) or polycarbonate (PC) material, with a thickness ranging from 1.0 mm to 4.0 mm, exhibiting high transparency (transmittance greater than 92% in the visible light range) and excellent mechanical stability. At least one side of the light guide plate matches the light emission surface of the LED light source array to achieve effective light coupling. A light extraction structure is provided on the bottom surface of the light guide plate, consisting of micron-scale scattering points, microprism arrays, or V-groove arrays, formed through laser engraving, precision molding, or printing processes. The density and geometry of the light extraction structure are precisely designed to uniformly emit the light coupled into the light guide plate from its upper surface towards the nano-scattering particle layer. The distribution density of the light extraction structure gradually increases from the LED light source array side towards the direction away from the LED light source array to compensate for light attenuation during propagation within the light guide plate, thereby ensuring uniform brightness of the light emitted from the upper surface of the light guide plate.

[0010] A nano-scattering particle layer is disposed on the upper surface of the light guide plate. The nano-scattering particle layer is composed of an optically transparent polymer substrate and uniformly dispersed nano-sized inorganic scattering particles therein. The thickness of the nano-scattering particle layer ranges from 20 micrometers to 200 micrometers, which is significantly thinner than that of traditional diffusers, thereby reducing the path length of light propagation and thus reducing light absorption loss.

[0011] Furthermore, the optically transparent polymer substrate is composed of one or more of polymethyl methacrylate (PMMA), polycarbonate (PC), cyclic olefin polymer (COP), or cyclic olefin copolymer (COC), and exhibits high transmittance (greater than 95%) and low inherent absorption in the visible light band. The refractive index of the polymer substrate is between 1.49 and 1.59.

[0012] Furthermore, the nanoscale inorganic scattering particles are composed of one or more of titanium dioxide (TiO2), silicon dioxide (SiO2), aluminum oxide (Al2O3), zirconium oxide (ZrO2), or barium sulfate (BaSO4). The average particle size of the nano-scattering particles ranges from 50 nm to 500 nm, and the standard deviation of the particle size distribution is less than 20% to ensure consistent scattering characteristics. The refractive index of the nano-scattering particles is between 2.0 and 2.7, forming a high refractive index difference with the refractive index of the polymer substrate, with a refractive index difference greater than 0.5. This effectively induces Mie scattering or Rayleigh scattering of light, achieving efficient forward scattering and diffusion of the beam at a specific angle. The volume percentage concentration of the nano-scattering particles ranges from 0.5% to 10%, and the concentration is precisely optimized to minimize multiple scattering and absorption losses of light within the layer while achieving the desired diffusion effect.

[0013] In a preferred embodiment of the present invention, the nano-scattering particles are surface-modified. Surface modification is achieved by grafting organosilane coupling agents (e.g., 3-methacryloyloxypropyltrimethoxysilane) or titanate coupling agents onto the surface of the nanoparticles to improve the compatibility of the nanoparticles with the polymer substrate, prevent the nanoparticles from agglomerating in the polymer substrate, thereby ensuring the uniform dispersion of the nanoparticles within the layer and maintaining the long-term stability of the optical properties of the nano-scattering layer.

[0014] In a preferred embodiment of the present invention, the distribution density of nano-scattering particles in the nano-scattering particle layer is non-uniform. This non-uniform distribution density is precisely optimized based on the luminous intensity distribution of the LED light source array and the distribution characteristics of the light extraction structure of the light guide plate. The distribution density of the nano-scattering particles can form a gradient within the nano-scattering particle layer; for example, the density of nano-scattering particles is relatively low in areas close to the LED light source array, while it gradually increases in areas farther away. Alternatively, the nano-scattering particles can be arranged in a preset microstructure array form, such as forming periodic micro-dot or micro-line patterns, with the spacing, size, and shape of the patterns exhibiting a changing trend within the nano-scattering particle layer. This non-uniform distribution design further optimizes the uniformity of light diffusion, compensating for the inherent brightness unevenness within the backlight by locally adjusting the scattering intensity. This achieves ultra-high brightness uniformity across the entire display area with extremely low light loss, reaching over 90%.

[0015] The nano-scattering particle layer is formed by coating a polymer dispersion containing nano-scattering particles onto the upper surface of the light guide plate using precision coating (e.g., slot coating, roll coating, or spin coating) or precision printing (e.g., inkjet printing or gravure printing) processes, and then forming a solid film through UV curing or thermal curing processes. An interface is formed between the nano-scattering particle layer and the light guide plate, and the interface is bonded with chemical bonding or optical adhesive to achieve a bubble-free and highly transparent connection.

[0016] An optical film assembly is disposed above the nano-scattering particle layer. The optical film assembly includes, but is not limited to: The first prism film has a periodic microprism structure facing the nano-scattering particle layer. The microprism structure is used to converge the light emitted from the nano-scattering particle layer onto the normal direction of the display, thereby improving the brightness of the front side. The prism apex angle of the first prism film is 90 degrees, and the prism spacing is 50 micrometers.

[0017] A second prism film, positioned above the first prism film, has its prism direction orthogonal to that of the first prism film, further enhancing the light-gathering effect. The prism apex angle of the second prism film is 90 degrees, and the prism spacing is 50 micrometers. A diffuser film, positioned above the second prism film, is used to further optimize the angular uniformity of the emitted light, preventing bright or dark streaks. The diffuser film is composed of a transparent polymer film with a micro-roughened surface, exhibiting a haze value of 60% and a light transmittance of 90%.

[0018] The optical film assembly is laminated and connected by optical adhesive or electrostatic adsorption, and is tightly attached to the nano-scattering particle layer.

[0019] This invention also provides a method for fabricating a low-power LED backlight containing nano-scattering particles, the method comprising the following steps: Step 1: Preparation of nano-scattering particle dispersion.

[0020] Step one includes: treating inorganic nanoparticles (e.g., titanium dioxide or alumina) with an average particle size of 50 to 500 nanometers using a surface modification process, which includes grafting an organosilane coupling agent onto the nanoparticle surface. The surface-modified nanoparticles are then dispersed at a volume percentage concentration of 0.5% to 10% in an optically transparent monomer or oligomer solution, the composition of which is matched to the material of the optically transparent polymer substrate. The dispersion process is carried out using methods such as ultrasonic vibration, high-speed stirring, or ball milling to ensure uniform and stable dispersion of the nanoparticles in the solution and prevent agglomeration. The viscosity of the dispersion is adjusted by adding appropriate solvents or rheology modifiers to meet the requirements of subsequent coating processes.

[0021] Step 2: Preparation and assembly of the reflective layer.

[0022] Step two includes: preparing a high-reflectivity polymer film or a reflective layer of multilayer dielectric film stacks. The high-reflectivity polymer film is prepared by vacuum sputtering a silver film onto a polyethylene terephthalate (PET) substrate and covering it with a silicon oxide protective layer. The reflective layer is cut to a predetermined size and prepared for subsequent assembly.

[0023] Step 3: Fabrication of the light guide plate.

[0024] Step three includes: preparing optical-grade polymethyl methacrylate (PMMA) or polycarbonate (PC) light guide plates through precision injection molding or extrusion molding processes. The bottom surface of the light guide plate is formed with micron-level scattering points, microprism arrays, or V-groove arrays, etc., through laser engraving, precision molding, or printing processes. The density and geometry of the light extraction structures are precisely designed to achieve uniform brightness of the light emitted from the upper surface of the light guide plate.

[0025] Step 4: Formation of the nano-scattering particle layer.

[0026] Step four involves precisely coating the nano-scattering particle dispersion prepared in step one onto the upper surface of the light guide plate prepared in step three, using a slit coating, roller coating, or spin coating process, to a thickness of 20 to 200 micrometers. The coating process is performed in a clean environment to avoid the introduction of dust particles. After coating, the coating is cured by ultraviolet (UV) radiation or thermal curing to form a solid nano-scattering particle layer with high transparency and uniform scattering properties. The parameters of the curing process (e.g., UV radiation intensity, exposure time or heating temperature and time) are precisely controlled to ensure complete cross-linking of the polymer substrate and optimization of its mechanical properties, while preventing the aggregation or degradation of nanoparticles.

[0027] In a preferred embodiment of the present invention, in step four, the coating of the nano-scattering particle dispersion can employ regional coating or mask coating techniques to achieve a non-uniform distribution of nano-scattering particles within the layer. This non-uniform distribution is pre-designed based on the luminous intensity distribution of the LED light source array and the distribution characteristics of the light extraction structure of the light guide plate, thereby further optimizing the uniformity of light diffusion. For example, by adjusting the speed of the coating head, the feed rate, or using an array of nozzles with different apertures for inkjet printing during the coating process, nano-scattering particle layers of different thicknesses or concentrations can be formed in different areas.

[0028] Step 5: Installation of the LED light source array.

[0029] Step five includes: fixing the LED light source array to the driver circuit board using a soldering process, and tightly attaching the LED light source array package to one or more sides of the light guide plate, or directly mounting it between the reflective layer and the bottom of the light guide plate to ensure efficient light coupling. The gap between the LED light source array and the light guide plate is filled with optical matching adhesive to minimize interface reflection loss.

[0030] Step Six: Assembly of the optical film assembly.

[0031] Step six includes: laminating optical films such as the first prism film, the second prism film, and the diffusion film in a predetermined order, and fixing them with optical adhesive or electrostatic adsorption to form an optical film assembly. The optical film assembly is then tightly bonded to the top of the nano-scattering particle layer. The lamination process is carried out in a dust-free environment with uniform pressure applied to ensure that the films are free of air bubbles and in close contact.

[0032] Step Seven: Final Packaging of the Backlight Module. Step Seven includes assembling and securing all the aforementioned layers (reflective layer, LED light source array, light guide plate, nano-scattering particle layer, and optical film assembly) within the backlight bezel using clips, screws, or adhesives for mechanical fixation. The bezel is made of polycarbonate or metal, and its dimensions and structure are precisely designed to provide structural support and protect the internal optical components. The backlight module is then subjected to optical performance testing, including brightness, uniformity, color temperature, and power consumption testing, to ensure it meets design specifications.

[0033] The beneficial effects of this invention are as follows: This invention discloses a low-power LED backlight containing nano-scattering particles and its fabrication method. By employing a nano-scattering particle layer with significantly reduced thickness, the propagation path of light within the diffusion layer is effectively shortened, thereby significantly reducing internal absorption loss. The particle size, refractive index, concentration, and spatial distribution of the nano-scattering particles in the nano-scattering particle layer are precisely optimized, ensuring that light primarily undergoes efficient forward scattering rather than non-directional volume scattering. This highly directional and efficient scattering characteristic of the nano-scattering particle layer significantly reduces the number of optical scattering operations and energy loss while achieving the desired brightness uniformity, thus directly improving the overall optical efficiency of the backlight. By achieving a non-uniform distribution of nano-scattering particles in the nano-scattering particle layer, such as gradient distribution or patterned distribution, the backlight can perform localized and precise control of light based on the actual light-emitting characteristics of the LED light source array and the light extraction efficiency of the light guide plate. This precise control strategy effectively compensates for potential brightness unevenness within the backlight and avoids the additional light loss caused by excessive scattering from traditional uniform diffusers, thus achieving excellent brightness uniformity of over 90% even under lower power consumption driving conditions. By tightly integrating a high-performance reflective layer beneath the light guide plate or LED light source array and working in synergy with a nano-scattering particle layer, it is ensured that any light scattered in the backlight direction or side can be efficiently recovered and redirected to the display area. The high reflectivity of the reflective layer (e.g., greater than 98%) combined with the high forward scattering efficiency of the nano-scattering particle layer minimizes light energy waste, significantly improves light energy utilization, and provides a solid foundation for achieving lower power consumption. The thickness of the nano-scattering particle layer used is only 20 to 200 micrometers, far less than the typical thickness of traditional diffuser plates (0.5 to 1 millimeter). This ultra-thin design not only directly reduces the thickness of the entire backlight module, meeting the stringent requirements of modern display products for thinness and lightness, but also further reduces manufacturing costs due to the reduction in material usage. Attached Figure Description

[0034] The invention will now be further described with reference to the accompanying drawings.

[0035] Figure 1 This is a structural framework diagram of a low-power LED backlight containing nano-scattering particles according to the present invention. Figure 2 This is a flowchart of a method for preparing a low-power LED backlight containing nano-scattering particles according to the present invention. Detailed Implementation

[0036] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0037] like Figure 1 As shown in the figure, an embodiment of the present invention discloses a low-power LED backlight containing nano-scattering particles and a method for fabricating the same, comprising an LED light source array, a reflective layer, a light guide plate, a nano-scattering particle layer, and an optical film assembly. These components work together in a specific stacking order and interface design to achieve the desired optical performance.

[0038] Specifically, the LED light source array includes multiple light-emitting diode (LED) chips, typically positioned on the side of a light guide plate to couple light into the plate, or alternatively on the bottom. The LED chips are electrically connected to a driver circuit board via a flexible printed circuit board (FPC) or a rigid printed circuit board (PCB). The driver circuit board provides precisely controlled drive current and voltage to ensure stable light emission from the LED chips. Preferably, the LED chips are high-efficiency white LEDs, such as packages based on blue chips exciting yellow phosphors, with a typical peak wavelength of 450 nm to 460 nm, a color temperature range adjustable to 6500 K, and a color rendering index (CRI) of 80 or higher. In some applications, a combination of red, green, and blue (RGB) LED chips can be used to achieve a wider color gamut coverage. The LED light source array can be configured as a point source array or a line source array, with a typical emission angle between 120 and 140 degrees to maximize light coupling into the incident surface of the light guide plate.

[0039] The reflective layer is located below the LED light source array or on the bottom surface of the light guide plate. Its main function is to reflect light that is not emitted along the display direction back into the backlight, thereby effectively improving light utilization efficiency. The selection of reflective layer materials and structural design have a decisive impact on the overall optical efficiency of the backlight. As a preferred embodiment of the present invention, the reflective layer is composed of a high-reflectivity polymer film. The base material of this film can be a polyethylene terephthalate (PET) substrate with a thickness between 125 micrometers and 250 micrometers. On one side of this PET substrate, a silver (Ag) thin film with an average thickness of 100 nanometers to 300 nanometers is deposited by high-vacuum magnetron sputtering or electron beam evaporation. The silver thin film has excellent visible light reflectivity. To prevent oxidation or mechanical damage to the silver layer, a silicon oxide (SiO2) or silicon nitride (SiN) protective layer with an average thickness of 20 nanometers to 50 nanometers is further covered on top. The average reflectivity of the reflective layer in the visible spectrum range can reach more than 97%. In one specific embodiment, the reflective layer can also be formed by stacking multiple dielectric films, which consist of alternating layers of high-refractive-index material (e.g., titanium dioxide TiO2, with a refractive index of approximately 2.5) and low-refractive-index material (e.g., silicon dioxide SiO2, with a refractive index of approximately 1.46). The dielectric films are deposited layer by layer using precision optical coating equipment, with a precisely designed single-layer thickness, typically one-quarter of the optical wavelength, to achieve an average reflectivity exceeding 98.5% in the visible spectrum range of 400 nm to 700 nm, while exhibiting low absorption loss characteristics. The reflective layer and the light guide plate can be laminated together using ultraviolet (UV)-cured optical adhesive. The refractive index of the optical adhesive matches that of the light guide plate material to minimize interface reflection, ensuring a bubble-free interface with high light transmittance. Alternatively, the reflective layer can be mechanically pressed into close contact with the light guide plate, ensuring good contact to reduce air gaps and facilitating disassembly and recycling. The reflective surface of the reflective layer faces the light guide plate and the nano-scattering particle layer to ensure maximum light recovery efficiency.

[0040] The light guide plate is positioned above or closely fitted to the reflective layer. It is integrally molded from optical-grade polymethyl methacrylate (PMMA) or polycarbonate (PC) material. Preferred PMMA materials, such as Mitsubishi Rayon's Acrylite® MS or Evonik Industries' PLEXIGLAS® 8N, offer greater than 93% transmittance in the visible light range and a refractive index of approximately 1.49, exhibiting excellent weather resistance and mechanical strength. PC materials, such as SABIC's Lexan™ series, offer greater than 90% transmittance and a refractive index of approximately 1.58, providing higher impact strength and heat resistance. The typical thickness of the light guide plate ranges from 1.0 mm to 4.0 mm, with 1.5 mm to 2.5 mm being commonly used to balance light guiding performance and thinness requirements. At least one side of the light guide plate is precision polished to ensure efficient light coupling with the light emitting surface of the LED light source array. The bottom surface of the light guide plate is equipped with a light extraction structure, which is crucial for achieving uniform light emission. This structure can consist of micron-sized scattering points, microprism arrays, or V-groove arrays. For example, micron-sized scattering points are typically circular or elliptical pits or bumps with diameters ranging from 20 to 150 microns. Microprism arrays can have prism apex angles of 60 to 90 degrees and prism spacing of 20 to 100 microns. V-groove arrays typically have groove widths and depths between 10 and 50 microns. The light extraction structure can be formed through laser engraving, precision molding, or high-precision printing processes. The density and geometry of the light extraction structure are precisely designed and optimized using optical simulation software (such as Zemax OpticStudio or TracePro) to ensure that light coupled into the light guide plate is uniformly emitted from its upper surface and directed towards the nano-scattering particle layer. To compensate for light attenuation during propagation within the light guide plate, the distribution density of the light extraction structure gradually increases from the LED light source array side towards the direction away from the LED light source array. For example, in a region 5 mm away from the LED light source array, the scattering point density can be 200 points / square millimeter, while in a region 0 mm away from the LED light source array, the scattering point density can be increased to 400 points / square millimeter, thereby ensuring that the brightness uniformity of the light emitted from the upper surface of the light guide plate reaches more than 85%.

[0041] The nano-scattering particle layer is the core component of this invention, and it is disposed on the upper surface of the light guide plate. The nano-scattering particle layer consists of an optically transparent polymer substrate and uniformly dispersed nano-sized inorganic scattering particles therein. Compared to traditional bulk scattering diffusers, the nano-scattering particle layer has a thickness ranging from 20 micrometers to 200 micrometers, with a typical thickness of 50 micrometers to 100 micrometers, significantly thinner than traditional diffusers (typically 0.5 millimeters to 1 millimeter), thereby effectively shortening the path length of light propagation and significantly reducing light absorption loss.

[0042] Furthermore, the optically transparent polymer substrate may be composed of one or more of polymethyl methacrylate (PMMA), polycarbonate (PC), cyclic olefin polymers (COP), or cyclic olefin copolymers (COC). The polymer substrate exhibits high transmittance in the visible light band (400 nm to 700 nm), for example, a spectral transmittance greater than 95%, and extremely low intrinsic absorption, with an absorption coefficient less than 0.01 cm⁻¹. The refractive index of the polymer substrate is between 1.49 and 1.59, preferably between 1.52 and 1.56, to achieve a good match with the refractive index of the optical film assembly. The substrate also needs to possess good mechanical properties, heat resistance, and weather resistance to ensure the long-term stability of the backlight.

[0043] Furthermore, the nanoscale inorganic scattering particles are composed of one or more of titanium dioxide (TiO2), silicon dioxide (SiO2), aluminum oxide (Al2O3), zirconium oxide (ZrO2), or barium sulfate (BaSO4). In a preferred embodiment, high-refractive-index TiO2 particles, such as anatase or rutile TiO2, with a refractive index between 2.5 and 2.7, are selected. The average particle size of the nanoscattering particles ranges from 50 nm to 500 nm, more preferably from 100 nm to 300 nm. Simultaneously, the standard deviation of the particle size distribution is controlled to be less than 20%, preferably less than 10%, for example, by measuring the particle size distribution using dynamic light scattering (DLS) technology to ensure the consistency and controllability of the scattering characteristics. The refractive index of the nanoscattering particles is between 2.0 and 2.7, forming a high refractive index difference with the polymer substrate. The refractive index difference is greater than 0.5, more preferably greater than 0.8; for example, the refractive index difference between TiO2 (2.5) and PMMA (1.49) is approximately 1.01. Such a significant difference in refractive index effectively induces Mie scattering or Rayleigh scattering of light, achieving efficient forward scattering and specific angular diffusion of the beam, rather than traditional diffuse reflection. The volume percentage concentration of the nano-scattering particles ranges from 0.5% to 10%, preferably from 1% to 5%. The concentration is precisely optimized, for example through Monte Carlo ray tracing simulations, to minimize multiple scattering of light within the layer and unnecessary absorption losses while achieving the desired diffusion effect (e.g., a full width at half maximum of 40 to 60 degrees).

[0044] In a preferred embodiment of the present invention, the nano-scattering particles undergo surface modification. Surface modification is achieved by grafting an organosilane coupling agent (e.g., 3-methacryloyloxypropyltrimethoxysilane, MPS) or a titanate coupling agent onto the surface of the nanoparticles. This modified layer covers the surface of the nanoparticles through chemical bonding or strong physical adsorption, forming a molecular-level interface layer. Its main function is to improve the compatibility between the nanoparticles and the polymer substrate, effectively reduce the van der Waals forces between the nanoparticles, prevent the nanoparticles from agglomerating in the polymer substrate, thereby ensuring the uniform dispersion of the nanoparticles within the layer and maintaining the long-term stability of the optical performance of the nano-scattering layer, avoiding localized brightness unevenness or decreased scattering efficiency due to agglomeration. Surface-modified nanoparticles can better integrate into the polymer matrix, reducing the haze of the scattering layer and improving its transparency.

[0045] In a preferred embodiment of the present invention, the distribution density of nano-scattering particles in the nano-scattering particle layer is non-uniform. This non-uniform distribution density is precisely optimized based on the luminous intensity distribution of the LED light source array and the distribution characteristics of the light extraction structure of the light guide plate. This optimization aims to compensate for the inherent brightness unevenness within the backlight, such as higher brightness near the LED light source and lower brightness further away. The distribution density of the nano-scattering particles can form a gradient within the nano-scattering particle layer. For example, in the region near the LED light source array, the density of nano-scattering particles is relatively low to allow more light to pass directly through; while in the region far from the LED light source array, the density of nano-scattering particles gradually increases, thereby enhancing the scattering intensity and improving brightness in that region. This gradient distribution can be achieved by adjusting the speed or feed rate of the coating head during the coating process. Alternatively, the nano-scattering particles can be arranged in a preset microstructure array form, such as forming periodic micro-dot or micro-line patterns, with the spacing, size, and shape of the patterns varying within the nano-scattering particle layer. For example, the diameter of the micro-dot pattern can gradually increase from 50 micrometers near the LED light source array to 150 micrometers far from the LED light source array, while the dot spacing gradually decreases from 200 micrometers to 100 micrometers. The non-uniform distribution design is used to further optimize the uniformity of light diffusion. By adjusting the scattering intensity locally, it compensates for the inherent brightness unevenness inside the backlight, thereby achieving ultra-high brightness uniformity of the entire display area with extremely low light loss. The brightness uniformity can reach more than 90%, preferably more than 92% (by measuring at different points with a luminance meter and calculating the ratio of the maximum brightness to the minimum brightness).

[0046] The nano-scattering particle layer is coated onto the upper surface of the light guide plate using precision coating (e.g., slot coating, roll coating, or spin coating) or precision printing (e.g., inkjet printing or gravure printing). The coating thickness is precisely controlled between 20 micrometers and 200 micrometers. After coating, a solid film is formed through UV curing or thermal curing. A tight interface is formed between the nano-scattering particle layer and the light guide plate. This interface is achieved through chemical bonding (e.g., covalent bonding between the substrate and the coating polymer molecular chains) or optical adhesive bonding, resulting in a bubble-free and highly transparent bond to avoid interface reflection loss.

[0047] An optical film assembly is positioned above the nano-scattering particle layer to further enhance the brightness, uniformity, and viewing angle characteristics of the emitted light. The optical film assembly typically includes a first prism film with a periodic microprism structure facing the nano-scattering particle layer. The microprism structure is usually precision-molded from optical-grade PMMA or PC material, with a prism apex angle of 90 degrees, a prism spacing of 50 micrometers, and prism directions parallel or perpendicular to the LED light source array direction. The microprism structure is used to converge the light emitted from the nano-scattering particle layer onto the normal direction of the display, thereby improving front brightness, typically by 30% to 50%.

[0048] The second prism film is positioned above the first prism film. The prism direction of the second prism film is orthogonal to that of the first prism film, typically at a 90-degree angle, to achieve two-dimensional light convergence, further enhancing the light convergence effect and improving the brightness of the front surface. The prism apex angle of the second prism film is also 90 degrees, and the prism spacing is 50 micrometers.

[0049] A diffusion film is disposed above the second prism film. The diffusion film further optimizes the spectral uniformity of the emitted light, prevents bright or dark streaks, and expands the effective viewing angle. The diffusion film is composed of a transparent polymer film (e.g., PMMA or PC) with a micro-roughened surface, achieving its diffusion function through surface texturing or the addition of micron-sized scattering particles. The typical haze value of the diffusion film ranges from 50% to 80%, preferably 60% to 70%, and the transmittance is 88% to 92%.

[0050] The optical films are laminated and connected using optical adhesive or electrostatic adsorption. UV-curable optical adhesives, which exhibit high light transmittance and stable adhesion after curing, are used. Electrostatic adsorption utilizes the inherent charge properties of the film materials to achieve adhesive-free bonding, reducing costs and simplifying the process. The optical films are tightly bonded to the nano-scattering particle layer, ensuring no air bubbles or gaps between layers to maintain optical performance.

[0051] like Figure 2 As shown, the present invention also provides a method for fabricating a low-power LED backlight containing nano-scattering particles, the method comprising the following detailed steps: Step 1: Preparation of nano-scattering particle dispersion.

[0052] Step one involves surface modification of nanoscale inorganic scattering particles and dispersion in a polymer solution. First, rutile titanium dioxide (TiO2) nanoparticles with an average particle size of 150 to 250 nanometers are selected, with a particle size distribution standard deviation controlled within 15%. The TiO2 nanoparticles are prepared via chemical precipitation or hydrothermal synthesis. Next, a surface modification process is performed. This process involves grafting an organosilane coupling agent, such as 3-methacryloyloxypropyltrimethoxysilane (MPS), onto the surface of the nanoparticles. Specifically, pretreated TiO2 nanoparticles (e.g., with surface adsorbed water removed by heat treatment) are added to a reactor containing a diluted MPS solution (e.g., isopropanol as solvent, MPS concentration 2% (w / w)). The mixture is stirred at 50°C to 80°C for 2 to 4 hours, allowing the trimethoxysilyl groups in the MPS to undergo a hydrolytic condensation reaction with the hydroxyl groups on the TiO2 surface, forming stable Si-O-Ti bonds. After the reaction was completed, unreacted coupling agents and byproducts were removed by centrifugation and washing (e.g., washing with isopropanol and deionized water alternately), and finally dried in a vacuum oven at 60°C for 12 hours to obtain surface-modified TiO2 nanoparticles.

[0053] Surface-modified TiO2 nanoparticles are dispersed at a volume percentage concentration of 3% to 5% in an optically transparent monomer or oligomer solution. The solution preferably consists of acrylate monomers (e.g., methyl methacrylate, MMA) and / or oligomers (e.g., polyurethane acrylates) and contains a photoinitiator (e.g., Irgarure 184, at a concentration of 0.5% to 1% (w / w)). The refractive index of the cured product of the monomer / oligomer system matches that of the photoconductor material, and it exhibits high transmittance in the visible light band. The dispersion process is carried out by multi-stage ultrasonic oscillation, high-speed stirring, or planetary ball milling. First, the particles were initially dispersed by ultrasonic vibration at a frequency of 20 kHz to 40 kHz for 30 minutes. Then, the particles were stirred for 2 hours in a high-speed mixer (1000 rpm to 5000 rpm) or milled for 4 to 8 hours in a planetary ball mill with zirconia balls (0.1 mm to 0.5 mm in diameter) to ensure uniform and stable dispersion of the nanoparticles in the solution, prevent agglomeration, and further narrow the particle size distribution. The viscosity of the dispersion was adjusted by adding appropriate reactive diluents (e.g., isobornyl acrylate) or rheology modifiers to achieve a viscosity range of 50 mPa·s to 200 mPa·s at 25°C to meet the requirements of subsequent precision coating processes.

[0054] Step 2: Preparation and assembly of the reflective layer.

[0055] Step two involves fabricating a high-reflectivity polymer film. Specifically, a 188-micrometer-thick PET substrate is used. A 150-nanometer-thick silver (Ag) film is deposited on one side of the PET substrate using magnetron sputtering in a vacuum, followed by a 30-nanometer-thick silicon oxide (SiO2) protective layer. The resulting high-reflectivity PET film achieves an average reflectivity of 97.5% in the 400-700 nanometer wavelength range. The reflective layer film is then cut to a predetermined size precisely matching the dimensions of the light guide plate using laser cutting or die-cutting. The reflective layer film is then prepared for subsequent lamination and assembly with the light guide plate. During assembly, the silver / silicon oxide side of the reflective layer faces the light guide plate.

[0056] Step 3: Fabrication of the light guide plate.

[0057] Step three involves fabricating an optical-grade PMMA light guide plate using a precision injection molding process. Acrylite® MS from MITSUBISHIRAYON is selected as the PMMA raw material. The PMMA is melted in an injection molding machine at a temperature of 240°C to 260°C and injected into a precision mold at an injection pressure of 100 MPa to 150 MPa. The mold cavity surface is ultra-precision machined to ensure that the upper surface of the light guide plate has optical-grade flatness (surface roughness Ra less than 5 nanometers). The thickness of the light guide plate is set to 2.0 mm. The bottom surface of the light guide plate is simultaneously and precisely molded to form a light extraction structure through microstructures on the mold cavity (such as microprism structures formed by laser etching or diamond cutting). The light extraction structure consists of an array of micro-scattering points with a diameter of 80 micrometers to 120 micrometers and a scattering point depth of 15 micrometers to 25 micrometers. The distribution density of scattering points increases linearly from 250 points / mm² on the LED light source array inlet side (e.g., 5 mm from the inlet) to 450 points / mm² on the side farther from the LED light source array (e.g., 200 mm from the inlet). The injection molding process is performed in a Class 1000 cleanroom environment to avoid particulate contamination. The molded light guide plate is then annealed (e.g., held at 80°C for 2 hours) to eliminate internal stress and improve dimensional stability.

[0058] Step Four: Formation of the Nano-Scattering Particle Layer. Step Four is the core step in the preparation method of this invention. The nano-scattering particle dispersion with a viscosity of 120 mPa·s prepared in Step One is coated onto the upper surface of the light guide plate prepared in Step Three with a precise thickness of 50 micrometers using a slot die coating process. The slot die coating equipment is equipped with a precision metering pump and a temperature control system to ensure a stable supply of the dispersion and uniform coating thickness. The coating process is carried out in a Class 100 cleanroom environment, and a laminar flow air supply system is used to maintain a high degree of cleanliness in the coating area to avoid the introduction of dust particles that could lead to optical defects. As a preferred embodiment of this invention, in Step Four, the coating of the nano-scattering particle dispersion employs a regional coating technique to achieve a non-uniform distribution of nano-scattering particles within the layer. The non-uniform distribution is pre-designed based on the luminous intensity distribution of the LED light source array and the distribution characteristics of the light extraction structure of the light guide plate. Specifically, by adjusting the flow rate of the feed pump in the slit coating die, a lower concentration of nano-scattering particle dispersion is applied in areas close to the LED light source array (e.g., areas 0 mm to 50 mm away from the LED light source array), resulting in a nano-scattering particle volume percentage concentration of 2.5% after curing. In areas farther from the LED light source array (e.g., areas 50 mm to 200 mm away from the LED light source array), the feed pump flow rate is gradually increased, increasing the nano-scattering particle volume percentage concentration to 4.5% after curing. This gradient coating method, achieved by adjusting the fluid supply in real time, ensures that the nano-scattering particle layer has different scattering intensities in different areas. After coating, the coating is cured using ultraviolet (UV) radiation to form a solid nano-scattering particle layer with high transparency and uniform scattering characteristics. The curing process uses a mercury lamp or LED UV light source, with the radiation intensity set to 500 mW / cm² to 1000 mW / cm² and the exposure time to 2 to 5 seconds. The parameters of the curing process are precisely controlled to ensure complete crosslinking of the acrylate monomers / oligomers and optimization of mechanical properties, while avoiding nanoparticle aggregation or degradation. The cured nano-scattering particle layer forms a tight interface with the PMMA light guide plate. The refractive index of the interface layer is close to that of the light guide plate, thereby minimizing interface reflection.

[0059] Step 5: Installation of the LED light source array.

[0060] Step five involves mounting the LED light source array onto an 8mm wide aluminum-based PCB using surface mount technology (SMT). The LED light source array consists of 10 white LED chips with a package size of 3020 and a luminous efficacy of 180 lumens / watt. The LED light source array package is tightly fitted to one long side of the light guide plate and secured with precision clamps. The gap between the LED light source array and the light guide plate is filled with transparent silicone optical matching adhesive with a refractive index of 1.50 to minimize interface reflection loss and ensure efficient light coupling, achieving a coupling efficiency of over 95%.

[0061] Step Six: Assembly of the optical film assembly.

[0062] Step six involves laminating the optical film assembly in a predetermined order. First, a first prism film (90-degree prism apex angle, 50-micrometer spacing, prism direction parallel to the LED light source array), a second prism film (90-degree prism apex angle, 50-micrometer spacing, prism direction perpendicular to the LED light source array), and a diffusion film (65% haze, 90% transmittance) are stacked sequentially. The optical film assembly is laminated in a Class 1000 cleanroom environment using a roller press with uniform pressure. The films are then fixed together using a low-viscosity UV-curable optical adhesive (refractive index 1.51) through dispensing, followed by UV curing to ensure air bubbles-free and tight contact between the films, forming the optical film assembly. The optical film assembly is then tightly bonded above the nano-scattering particle layer.

[0063] Step 7: Final packaging of the backlight module.

[0064] Step seven involves assembling and securing all the aforementioned layers (reflective layer, LED light source array, light guide plate, nano-scattering particle layer, and optical film assembly) within a backlight frame injection-molded from ABS / PC alloy. The frame dimensions are 500 mm x 300 mm x 5 mm (length x width x height). The components are mechanically secured using precision clips and a small number of screws on the frame, ensuring structural stability and ease of maintenance. Inside the frame, white reflective tape with a reflectivity greater than 95% is used to shield and reflect light from the sidewalls, further reducing lateral light leakage. The backlight module is then subjected to optical performance testing. The tests include: Brightness test: The average brightness was evaluated by measuring multiple points at the center and edge of the backlight emitting surface using a BM-7A luminance meter.

[0065] Brightness uniformity test: Brightness is measured at 9 or 13 standard points in the display area, and the ratio of maximum brightness to minimum brightness is calculated and expressed as a percentage.

[0066] Color temperature and color rendering index test: The color temperature (CCT) and color rendering index (CRI) of the emitted light were measured using a PR-655 spectroradiometer.

[0067] Power consumption test: The input power of the LED driver circuit is measured using a high-precision power meter. All test results must meet the design specifications to ensure that the backlight performance meets the requirements, such as an average brightness of 3000 cd / m², brightness uniformity of over 90%, color temperature of 6500K±500K, and CRI>80.

[0068] In one specific embodiment, the above-mentioned technical solution of the present invention manufactures an LED backlight module with a size of 15.6 inches.

[0069] Example 1: Low-power LED backlight containing nano-scattering particles LED light source array: 12 white LEDs in 3020 package, installed on the long side of the light guide plate with a spacing of 25 mm, and a total power consumption of 10W.

[0070] Reflective layer: 188-micron PET substrate, sputtered with a 150-nanometer Ag film and covered with a 30-nanometer SiO2 protective layer, with a reflectivity of 97.8%. It is laminated with the light guide plate via optical adhesive.

[0071] Light guide plate: 2.0 mm thick optical-grade PMMA plate, measuring 345 mm x 195 mm. The bottom surface is laser-engraved to form a micro-scattering point array, with scattering points having a diameter of 100 micrometers and a depth of 20 micrometers. The scattering point density linearly increases from 250 points / mm² on the LED side to 450 points / mm² at the far end.

[0072] Nanoparticle scattering layer: Coated on the upper surface of the light guide plate, with a thickness of 50 micrometers. The polymer substrate is an acrylate oligomer (refractive index 1.52), and the nanoparticles are surface-modified TiO2 (rutile type, average particle size 200 nm, refractive index 2.70). The volume percentage concentration of TiO2 particles increases in a gradient from 2.5% near the LED side to 4.5% at the far end.

[0073] Optical film assembly: consists of two 90-degree prism films (prism spacing 50 micrometers) and a diffusion film with 65% haze.

[0074] To quantify the technical effects of the present invention, we set up a comparative example, which adopts a traditional LED backlight structure.

[0075] Comparative Example 1: Traditional LED Backlight LED light source array: 12 white LEDs in 3020 package, installed on the long side of the light guide plate with a spacing of 25 mm, and a total power consumption of 10W.

[0076] Reflective layer: Same as in Example 1.

[0077] Light guide plate: 2.0 mm thick optical-grade PMMA plate, measuring 345 mm x 195 mm. The bottom surface is laser-engraved to form a micro-scattering point array, with scattering points having a diameter of 100 micrometers and a depth of 20 micrometers. The scattering point density linearly increases from 250 points / mm² on the LED side to 450 points / mm² at the far end.

[0078] Diffuser plate: A traditional 0.8 mm thick PMMA diffuser plate is used, with micron-sized (average particle size 5 microns) PS (polystyrene) scattering particles uniformly dispersed inside, with a haze value of 75% and a light transmittance of 88%. This diffuser plate is located above the light guide plate.

[0079] Optical film assembly: Same as in Example 1.

[0080] Optical performance and power consumption were tested on the backlight modules of Example 1 and Comparative Example 1. The test environment was a temperature- and humidity-controlled cleanroom, and the test equipment was a Konica Minolta CS-2000A spectroradiometer and a Keithley 2400 power supply / multimeter. Power consumption was adjusted under the same target average brightness (e.g., set to 2500 cd / m²), and other performance indicators were measured.

[0081] Performance indicators Example 1 (invention) Comparative Example 1 (conventional diffusion plate) Improvement percentage (relative to Comparative Example 1) Optical efficiency 75.2% 62.5% +20.3% Luminance uniformity 93.5% 86.2% +8.5% Power consumption (to reach 2500 cd / m2) 7.8 W 10.0 W -22.0% Total module thickness 3.2 millimeters 3.8 millimeters -15.8% Central zone luminance 2510 cd / m2 2505 cd / m2 - Color temperature (CCT) 6520 K 6480 K - Color rendering index (CRI) 82 81 - The experimental data above demonstrate that the LED backlight with a nano-scattering particle layer of the present invention exhibits significant advantages in optical efficiency, brightness uniformity, power consumption, and module thickness. Example 1, by employing a nano-scattering particle layer with a thickness of only 50 micrometers, effectively shortens the propagation path of light in the diffusion medium. Combined with its optimized nanoparticle scattering characteristics and gradient distribution design, it significantly reduces light absorption loss and disordered scattering, thereby increasing the optical efficiency from 62.5% in Comparative Example 1 to 75.2%, achieving a relative improvement of up to 20.3%. This efficiency improvement is directly reflected in the power consumption significantly decreasing from 10.0 W in Comparative Example 1 to 7.8 W when achieving the same target brightness of 2500 cd / m², a reduction of 22.0%. Furthermore, due to the non-uniform distribution design of the nano-scattering particle layer, the present invention can more accurately compensate for the inherent brightness unevenness of the light guide plate, improving the brightness uniformity from 86.2% in Comparative Example 1 to 93.5%, reaching an industry-leading level. Meanwhile, the extremely thin nano-scattering particle layer further reduces the overall thickness of the backlight module from 3.8 mm in Comparative Example 1 to 3.2 mm, achieving a 15.8% thickness optimization, fully meeting the stringent requirements of modern display devices for thinness and lightness. These quantitative data fully demonstrate the innovation and technological superiority of this invention in achieving low power consumption, high efficiency, excellent brightness uniformity, and ultra-thinness.

[0082] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low-power LED backlight containing nano-scattering particles, characterized in that, include: The LED light source array includes multiple light-emitting diode chips, which are disposed on the side or bottom of the light guide plate. The light-emitting diode chips are connected to the driving circuit board via electrical connection, and the driving circuit board provides driving current to make them emit light. The LED light source array emits light in the form of point light source or line light source and couples it into the light guide plate. The reflective layer, located below the LED light source array or on the bottom surface of the light guide plate, is made of a material with high reflectivity, including but not limited to high reflectivity polymer films or multilayer dielectric film stacks. It is used to reflect light that is not emitted along the display direction back into the back light source to improve light utilization efficiency. The reflective surface of the reflective layer faces the light guide plate and the nano-scattering particle layer. The light guide plate, which is set above or closely attached to the reflective layer, is integrally molded from optical-grade polymethyl methacrylate or polycarbonate material with a thickness ranging from 1.0 mm to 4.0 mm. The bottom surface of the light guide plate is provided with a light extraction structure, which consists of micron-sized scattering points, microprism arrays, or V-groove arrays, and is used to uniformly emit the light coupled into the light guide plate from the upper surface of the light guide plate. The nano-scattering particle layer, set on the upper surface of the light guide plate, is composed of an optically transparent polymer substrate and uniformly dispersed nano-sized inorganic scattering particles. The thickness of the nano-scattering particle layer ranges from 20 micrometers to 200 micrometers, and is used to achieve efficient forward scattering and diffusion of light beams at specific angles. An optical film assembly, disposed above the nano-scattering particle layer, includes at least one prism film and one diffusion film, for further optimizing and converging the light emitted from the nano-scattering particle layer onto the normal direction of the display.

2. The low-power LED backlight containing nano-scattering particles according to claim 1, characterized in that, The optically transparent polymer substrate in the nanoscattering particle layer is composed of one or more of polymethyl methacrylate, polycarbonate, cyclic olefin polymers or cyclic olefin copolymers.

3. The low-power LED backlight containing nano-scattering particles according to claim 1, characterized in that, The nanoscale inorganic scattering particles are composed of one or more of titanium dioxide, silicon dioxide, aluminum oxide, zirconium oxide, or barium sulfate.

4. A low-power LED backlight containing nano-scattering particles according to claim 1, characterized in that, The nano-scattering particles are surface-modified by grafting organosilane coupling agents onto the surface of the nanoparticles.

5. A low-power LED backlight containing nano-scattering particles according to claim 1, characterized in that, The distribution density of nano-scattering particles in the nano-scattering particle layer is non-uniform. The non-uniform distribution density is precisely optimized based on the luminous intensity distribution of the LED light source array and the distribution characteristics of the light extraction structure of the light guide plate. The distribution density of nano-scattering particles can form a gradient within the nano-scattering particle layer.

6. A method for fabricating a low-power LED backlight containing nano-scattering particles, characterized in that, Including the following: S1. Preparation of nano-scattering particle dispersion, including surface modification of inorganic nano-scattering particles with an average particle size of 50 nanometers to 500 nanometers, and dispersion of the surface-modified nano-scattering particles at a volume percentage concentration of 0.5% to 10% in an optically transparent monomer or oligomer solution. S2. Prepare a light guide plate with a thickness ranging from 1.0 mm to 4.0 mm. The light guide plate is integrally formed from optical grade polymethyl methacrylate or polycarbonate material, and its bottom surface is formed with light extraction structures such as micron-level scattering points, micro prism arrays or V-groove arrays through laser engraving, precision molding or printing processes. S3. Forming a nano-scattering particle layer on the upper surface of the light guide plate, including coating the nano-scattering particle dispersion liquid onto the upper surface of the light guide plate with a thickness of 20 micrometers to 200 micrometers through a precision coating or precision printing process, and forming a solid film with high transparency and uniform scattering characteristics through a UV curing or thermal curing process. S4. Assemble the reflective layer, LED light source array, optical film assembly, and light guide plate with nano-scattering particle layer. The assembly process includes placing the reflective layer below the LED light source array or on the bottom surface of the light guide plate, tightly attaching the LED light source array package to one or more sides of the light guide plate or directly mounting it between the reflective layer and the bottom of the light guide plate, and tightly attaching the optical film assembly to the top of the nano-scattering particle layer. S5. Perform final packaging on the assembled backlight module, including assembling and fixing all layers within the backlight bezel, and conducting optical performance tests on the backlight module to ensure it meets design specifications.

7. The method for fabricating a low-power LED backlight containing nano-scattering particles according to claim 6, characterized in that, The specific steps for preparing a nano-scattering particle dispersion include: grafting an organosilane coupling agent onto the surface of inorganic nano-scattering particles with an average particle size of 150 nanometers to 250 nanometers.

8. The method for preparing a low-power LED backlight containing nano-scattering particles according to claim 6, characterized in that, The specific steps for forming a nano-scattering particle layer on the upper surface of the light guide plate include: coating a nano-scattering particle dispersion onto the upper surface of the light guide plate with a precise thickness of 50 to 100 micrometers using slit coating, roller coating, or spin coating processes; after coating, curing the coating by ultraviolet radiation or thermal curing processes to form a solid nano-scattering particle layer with high transparency and uniform scattering characteristics; and achieving a bubble-free and highly transparent connection between the nano-scattering particle layer and the light guide plate through chemical bonding or optical adhesive bonding.

9. The method for preparing a low-power LED backlight containing nano-scattering particles according to claim 6, characterized in that, In the formation of a nano-scattering particle layer on the upper surface of the light guide plate, the nano-scattering particle dispersion is coated using regional coating or mask coating techniques to achieve a non-uniform distribution of nano-scattering particles within the nano-scattering particle layer. The non-uniform distribution is pre-designed based on the luminous intensity distribution of the LED light source array and the distribution characteristics of the light extraction structure of the light guide plate. The coating process involves adjusting the speed of the coating head, the amount of material supplied, or using an array of nozzles with different apertures for inkjet printing to form nano-scattering particle layers of different thicknesses or concentrations in different areas.

10. The method for fabricating a low-power LED backlight containing nano-scattering particles according to claim 6, characterized in that, The specific steps for fabricating the light guide plate include: using optical-grade polymethyl methacrylate or polycarbonate materials to prepare a light guide plate with a thickness ranging from 1.5 mm to 2.5 mm through precision injection molding or extrusion molding processes; at least one side of the light guide plate is precision polished to ensure high-efficiency light coupling with the light emitting surface of the LED light source array; the bottom surface of the light guide plate is formed with micron-level scattering points, microprism arrays, or V-groove arrays, etc., through laser engraving, precision molding, or high-precision printing processes; the distribution density of the light extraction structures gradually increases from the side of the LED light source array towards the direction away from the LED light source array.

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