Backlight module and display device

Abstract

The utility model 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] This utility model relates to the field of display technology, and in particular to a backlight module and a display device. Background Technology

[0002] In the field of LCD backlight modules, the solution using red (R), green (G), and blue (B) LEDs (Light Emitting Diodes) as the light source is widely used due to its wide color gamut coverage and controllable cost. However, due to the characteristics of LED devices and the optical design of backlight modules, there are two major technical bottlenecks in practical applications: one is the brightness decay and color shift caused by temperature, and the other is the color crosstalk 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 three-color LEDs differ significantly at high temperatures (e.g., red LEDs decay more rapidly than green LEDs), and their color coordinate shift directions are inconsistent, leading to fluctuations in the color temperature of the mixed white light. Furthermore, uneven distribution of heat-generating components in the backlight module causes temperature differences on the display plane, exacerbating local color deviations. Existing dynamic compensation solutions rely on high-density temperature sensors and high-performance chips, but this increases hardware costs and requires additional compensation chips, making it difficult to meet the cost-effectiveness requirements of consumer products.

[0004] On the other hand, due to the difference between the LED package size and the sub-pixel size of the LCD screen, the backlight mixing area overlaps, causing color bleeding between adjacent pixels. When displaying adjacent light and dark images (such as white and red), the light-colored area experiences a decrease in color purity due to stray light from other colored LEDs, resulting in a subjective visual appearance of color cast. Existing solutions can only partially alleviate the problem by optimizing the driving algorithm, and cannot fundamentally eliminate the color bleeding phenomenon, thus necessitating innovation at the optical architecture level.

[0005] The aforementioned problems directly lead to a decrease in display uniformity and color reproduction distortion, becoming key factors restricting the improvement of display product performance. Utility Model Content

[0006] This application provides a backlight module and a display device that can suppress thermal interference and eliminate light mixing and color crossing.

[0007] This application provides a backlight module, including:

[0008] A light source assembly for emitting polarized light;

[0009] A first liquid crystal display (LCD) screen is disposed on the light-emitting side of the light source assembly. The first LCD screen includes a liquid crystal layer and a color filter. The liquid crystal layer is used to control the amount of polarized light passing through. The color filter is disposed on the light-emitting side of the liquid crystal layer. The color filter includes 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. The red light, the green light, and the blue light are mixed to form a backlight.

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

[0011] In some embodiments, the light-emitting unit is a blue light source, and 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.

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

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

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

[0015] In some embodiments, the backlight module further includes a light-diffusing layer disposed between the polarizing lens and the first liquid crystal screen for homogenizing 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 to form pixel-level partitioned light emission.

[0017] In some embodiments, the backlight module further includes a polarizer disposed on the light-emitting side of the first liquid crystal screen, wherein 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 the side of the liquid crystal layer away from the color filter and is used to drive the liquid crystal layer.

[0019] This application embodiment also provides a display device, including:

[0020] Backlight module, wherein the backlight module is the aforementioned backlight module;

[0021] The second LCD screen is 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 LCD screen is consistent with the polarization direction of the polarized light emitted from 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 such that the backlight module has a first resolution; the second liquid crystal screen has a second resolution; and the first resolution is less than or equal to the second resolution.

[0023] The backlight module and display device provided in this application include a backlight module comprising a light source assembly and a first liquid crystal screen. The light source assembly is used to emit polarized light. The first liquid crystal screen includes a liquid crystal layer and a color filter. The liquid crystal layer is used to control the amount of polarized light passing through, and the color filter is disposed on the light-emitting side of the liquid crystal layer. The color filter includes 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. The red, green, and blue light are mixed to form the backlight. On the one hand, by abandoning the traditional red / green / blue (R / G / B) three-color LED light source and using the first liquid crystal screen to reconstruct the three-color light, the problems of brightness attenuation and color shift caused by LED heating are avoided from the root, significantly improving the stability of the light source. On the other hand, this application can perform real-time and precise control of polarized light through the liquid crystal layer. Combined with the arrayed layout of the color filter, adjacent three-color light achieves pixel-level isolation in space, completely eliminating the color crosstalk phenomenon caused by optical path overlap in the traditional solution, ensuring the accuracy and consistency of color display. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1This is a schematic diagram of a first structure of a backlight module provided in an embodiment of this application.

[0026] Figure 2 This is a schematic diagram of a first structure of a first liquid crystal screen provided in an embodiment of this application.

[0027] Figure 3 This is a schematic diagram of a second structure of the first liquid crystal screen provided in an embodiment of this application.

[0028] Figure 4 This is a schematic diagram of a second structure of the backlight module provided in an embodiment of this application.

[0029] Figure 5 This is a schematic diagram of a third structure of the backlight module provided in an embodiment of this application.

[0030] Figure 6 This is a schematic diagram of a fourth structure of the backlight module provided in the embodiments of this application.

[0031] Figure 7 This is a schematic diagram of the fifth structure of the backlight module provided in the embodiments of this application.

[0032] Figure 8 This is a schematic diagram of the sixth structure of the backlight module provided in the embodiments of this application.

[0033] Figure 9 This is a schematic diagram of the structure of the display device provided in the embodiments of this application. Detailed Implementation

[0034] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0035] This application provides a backlight module and a display device that can suppress thermal interference and eliminate light mixing and color crosstalk. The following is a detailed description in conjunction with the accompanying drawings.

[0036] Please see Figure 1 , Figure 1 This is a schematic diagram of a first structure of a backlight module provided in an embodiment of this application.

[0037] This application provides a backlight module 10, 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 LCD panel, enabling it to display images correctly. The backlight module 10 typically consists of a light source, a light guide plate, and optical films. By rationally combining these components, the light emitted from the light source is shaped, diffused, and homogenized to meet the backlight requirements of the LCD panel. The backlight module 10 provided in this application can be applied to Local Dimming technology, enabling individual control of each zone, thereby achieving dynamic adjustment of the brightness and color of each zone, resulting in higher contrast and a clearer, more detailed image.

[0038] The backlight module 10 includes a light source assembly 11 and a first LCD screen 12.

[0039] The light source assembly 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 see Figure 1 as well as Figure 2 , Figure 2 This is a schematic diagram of a first structure of a first liquid crystal display (LCD) provided in an embodiment of this application. The first LCD 12 is disposed on the light-emitting side of the light source assembly 11. The first LCD 12 includes a liquid crystal layer 121 and a color filter 122. The liquid crystal layer 121 is used to control the amount of polarized light passing through, and 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 component of the first LCD 12, utilizing the special physical properties of liquid crystal molecules under the action of an electric field to control the amount of polarized light passing through. When different electric fields are applied to both sides of the liquid crystal layer 121, the alignment direction of the liquid crystal molecules changes, 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 transmission axis of the polarizer. By precisely controlling the alignment of the liquid crystal molecules, the amount of polarized light passing through can be precisely controlled.

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

[0042] Specifically, the red sub-filter area 1221 allows only red light within a specific wavelength range to pass through, the green sub-filter area 1222 allows only green light to pass through, and the blue sub-filter area 1223 allows only blue light to pass through. When polarized light passes through the liquid crystal layer 121 and then through the color filter 122, the different colored sub-filter areas will respectively filter out the corresponding red, green, and blue light. When these three basic colors of light are mixed according to a certain intensity ratio, various backlight colors and intensities can be formed to create zoned displays.

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

[0044] Specifically, the red sub-filter region 1221, green sub-filter region 1222, and blue sub-filter region 1223 can be arranged neatly 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 one red sub-filter region 1221, one green sub-filter region 1222, and one blue sub-filter region 1223. Through this arrangement, pixel-level zoned emission is achieved.

[0045] Taking the display of a high-definition image as an example, each detail in the image corresponds to a pixel unit. During the display process, the system precisely controls the amount of light passing through the red sub-filter area 1221, green sub-filter area 1222, and blue sub-filter area 1223 of 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 increases the amount of light passing through the red sub-filter area 1221 while decreasing the amount of light passing through the green sub-filter area 1222 and blue sub-filter area 1223, thus making the pixel appear red. Through this pixel-level partitioned light emission method, a red backlight is formed, thereby achieving backlight partitioning.

[0046] Therefore, in this embodiment, 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 screen. When the first LCD screen 12 can adjust the brightness and even the color of each area, making the bright parts of the screen brighter and the dark parts darker, the contrast and sense of layering of the screen are greatly improved, bringing a more realistic and stunning visual experience to the audience.

[0047] Compared to ordinary multi-zone RGB backlighting, the number of zones in this application embodiment has a significant advantage. Ordinary RGB backlighting has only dozens or hundreds of zones, while this application can reach several times or even tens of times that number. More zones can more accurately correspond to screen areas, allowing for more detailed adjustments to brightness and color. When displaying complex images, it can better adapt to changes in brightness, avoiding areas that are too bright or too dark, resulting in a more uniform and natural image.

[0048] Ordinary RGB backlighting is prone to brightness decay and color shift due to aging of the light-emitting unit 111, requiring algorithm compensation. This application's embodiment, with its precise zone control and pixel-level color adjustment, can adjust brightness and color in real time without algorithm compensation, reducing the accumulation of errors caused by algorithm compensation.

[0049] Please refer to Figure 3 , Figure 3 This is a schematic diagram of a second structure of the first liquid crystal display screen provided in an embodiment of this application. The backlight module 10 further includes a polarizer 14, which is disposed on the light-emitting side of the first liquid crystal display 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 capable of selectively transmitting light with a specific polarization direction. The polarizer 14 is made of a dichroic material, allowing only 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 often used to control the polarization state of light to achieve light modulation and optimize display effects.

[0050] When polarized light is emitted 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 light components with other polarization directions are absorbed or blocked. This design can further improve the light utilization efficiency and the contrast of the displayed image. For example, when displaying a black image, the polarizer 14 can effectively reduce the interference of stray light, making the black area purer, thereby improving the overall contrast of the image.

[0051] Please continue reading. Figure 3 The first LCD screen 12 also 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 a 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, respectively disposed on both sides of the liquid crystal layer 121, the color filter 122, and the thin-film transistor layer 123. The first and second transparent encapsulation layers are tightly bonded together to form a sealed space, completely encapsulating the internal components. This dual-layer encapsulation design not only enhances the mechanical strength of the transparent encapsulation structure 124, improving its impact and wear resistance, but also further improves its sealing performance, effectively preventing the intrusion of external substances.

[0054] A 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 in the liquid crystal layer 121 according to these signals, thereby achieving precise control of the amount of light transmitted, and thus achieving color and brightness regulation of the light, thereby realizing backlight zoning.

[0055] In other words, the backlight module 10 is divided into multiple independent areas, and the brightness of each area can be adjusted independently according to the content of the screen. When the first LCD screen 12 precisely controls the light in a certain area, the backlight module 10 can adjust the brightness of that area accordingly, making the bright parts of the screen brighter and the dark parts darker, thereby greatly improving the contrast and sense of depth of the screen and bringing a more realistic and stunning visual experience to the audience.

[0056] Please see Figure 4 , Figure 4 This is a schematic diagram of a second structure of the backlight module provided in an embodiment of this application. The light source assembly 11 includes a light-emitting unit 111 and a polarization assembly 112. The light-emitting unit 111 is used to emit light from the light source. The light-emitting unit 111 efficiently converts the input electrical energy into light energy through an internal physical mechanism and emits light from the light source. 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 current passes through a semiconductor material, electrons and holes recombine, releasing energy and radiating it out in the form of photons, thereby generating light. This light source is natural light in its initial state, and the vibration direction of its light waves is randomly distributed in a plane perpendicular to the propagation direction, without specific polarization characteristics.

[0057] A 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 with 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 the polarization component 112 can pass through, while the light components with other polarization directions will be absorbed or blocked, thereby converting the light from the light source into polarized light.

[0058] Taking a liquid crystal display (LCD) as an example, polarized light processed by polarization component 112 enters the liquid crystal layer 121. Under the influence of an electric field, the liquid crystal molecules undergo a change in alignment, thereby altering the polarization state of the polarized light. Then, different colors of light are filtered out by color filter 122, ultimately achieving backlight zoning. If the light source light enters the liquid crystal layer 121 directly without processing by polarization component 112, due to the randomness of the light polarization direction, it cannot be effectively modulated by the liquid crystal molecules, leading to problems such as blurry images and low contrast. Therefore, 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 also includes a back plate 15, which has a reflective cavity. The light-emitting unit 111 in the light source assembly 11 is disposed in the reflective cavity, and a reflective sheet is attached to the inner wall of the reflective cavity.

[0060] The backplate 15 is usually made of high-strength, high-temperature resistant and rigid materials, such as metal (e.g., aluminum alloy), to ensure that it can withstand the weight of the internal components and the mechanical stress that may be generated during the operation of the backlight module 10, while ensuring the stability of the structure and avoiding the impact of deformation on optical performance.

[0061] The light-emitting units 111 in the light source assembly 11 are precisely positioned within the reflective cavity. The installation position and spacing of the light-emitting units 111 are precisely calculated to ensure that the light is evenly distributed in the backlight module 10. During installation, specific fixing methods are used, such as welding, bonding, or using a dedicated fixing bracket, to firmly fix the light-emitting units 111 to the bottom of the reflective cavity.

[0062] The inner wall of the reflective cavity is fitted with a reflective sheet. The reflective sheet has a high reflectivity and can effectively reflect the light emitted by the light-emitting unit 111 to the polarization component 112, thereby reducing the absorption and loss of light in the reflective cavity.

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

[0064] Please continue reading. Figure 4In a first embodiment of the light source assembly 11, the light-emitting unit 111 is a blue light source, and the polarization assembly 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), a material with advantages such as high transparency, good processability, and certain mechanical strength. Simultaneously, nanoparticles with birefringence properties, such as titanium dioxide (TiO2), zinc oxide (ZnO), and silicon nanoparticles (SiO2), are doped into the PMMA material. Birefringence refers to the different refractive indices of a material in different directions, which allows the doped PMMA material to influence the polarization state and propagation direction of light. The doped PMMA material can also be treated with external stress, mechanical stretching, etc., to further enhance its polarization properties.

[0066] For example, when light from the light source passes through the polarization diffusion layer 1121, the light undergoes scattering and polarization modulation. Scattering can make the light distribution more uniform, avoiding local over-brightness or under-brightness; while polarization modulation will give some light a specific polarization direction, preparing it for subsequent optical processing (entering the first liquid crystal screen 12).

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

[0068] In the area of ​​polarization separation induced by doping with birefringent nanoparticles, when nanoparticles with birefringent properties, such as titanium dioxide (TiO2), zinc oxide (ZnO), and silicon nanoparticles (SiO2), are incorporated into PMMA materials, the material exhibits anisotropy of refractive index, meaning that the refractive index varies in different directions. Upon incident with natural light, according to the Huygens-Fresnel principle, it decomposes into ordinary ray (o-ray) and extraordinary ray (e-ray) with perpendicular polarization directions. The o-ray vibrates perpendicular to the plane formed by the light propagation direction and the material's optical axis, obeying the law of refraction; the e-ray vibrates within this plane and does not obey the law of refraction. Simultaneously, the nanoparticles exhibit differences in scattering and absorption of light with different polarization directions, resulting in significant propagation loss in one polarization direction and relatively easy transmission in another. This enhances the intensity of the light with the higher polarization in the outgoing light, achieving selective transmission of polarized light and strengthening the polarization characteristics.

[0069] In terms of altering material structure through external stress or mechanical stretching, applying stress or stretching to doped PMMA materials changes its internal microstructure, altering the arrangement and spacing of nanoparticles within the PMMA matrix, and enhancing optical anisotropy. For example, stress may cause nanoparticles to align in a specific direction, thereby changing the material's optical axis and birefringence properties. By rationally controlling the degree and direction of stress or stretching, the polarization characteristics of the material can be precisely controlled, such as maximizing the intensity of light in a certain polarization direction in the emitted light, or causing a specific rotation of the polarization direction of polarized light, thus achieving the generation and control of polarized light.

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

[0071] Quantum dot layer 1122 uses a PET (Polyethylene Terephthalate) substrate doped with quantum dot materials. Quantum dot layer 1122 is used to convert some blue polarized light into red and green polarized light; the blue, red, and green polarized light mix to form white polarized light. Quantum dots, as nanoscale semiconductor materials, possess a unique quantum confinement effect. Their size is typically between a few nanometers and tens of nanometers. Quantum dots of different sizes have different band structures, allowing them to absorb specific wavelengths of light and emit different colors of light. For example, smaller quantum dots may absorb blue light and emit green light, while slightly larger quantum dots may absorb blue light and emit red light.

[0072] Please continue reading. Figure 4 A second embodiment of the light source component 11: Based on the first embodiment of the light source component 11, the quantum dot layer 1122 can also be a polarization quantum dot layer, meaning that the quantum dot layer 1122 also has a polarization-maintaining function. This means that during the light color conversion process, the polarization state of the light can be kept unchanged. This characteristic is crucial for improving the contrast and color purity of the display device. Specifically, lithium niobate (LiNbO3) nanoparticles, titanium dioxide (TiO2) nanoparticles, etc., are doped into the substrate of the quantum dot layer 1122. These nanoparticles have unique optical properties and can interact with light, thereby achieving the protection of the polarization state of light. For example, lithium niobate nanoparticles have an electro-optic effect; when an electric field is applied, their refractive index changes. 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 performance, which can scatter and modulate the polarization of light, enhancing the polarization-maintaining ability of the quantum dot layer 1122.

[0073] The nanoparticles mentioned in this application are merely illustrative examples. The specific choice of nanoparticles depends on the application requirements (such as optical performance, transparency, processability, etc.) and the polarization strength requirements of the overall backlight module 10.

[0074] Please see Figure 5 , Figure 5 This is a schematic diagram of a third structure of the backlight module provided in an embodiment of this application.

[0075] A third embodiment of the light source assembly 11: the light-emitting unit 111 is a blue light source, and the polarization assembly 112 includes a quantum dot polarization diffuser 1123, which is disposed on the light-emitting side of the blue light source.

[0076] The quantum dot polarization diffuser 1123 has the functions of changing the color of light, polarization, and diffusion.

[0077] The quantum dot polarization diffuser 1123 is doped with quantum dot material. This quantum dot material is the same as that used in the previous embodiment, and will not be described again here.

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

[0079] The quantum dot polarization diffuser 1123 also has a diffusion effect because it is doped with nanoparticles. When light enters the diffuser, it is scattered on the surface of the nanoparticles. These nanoparticles are the same as those in the previous embodiment and will not be described again here.

[0080] It is understandable that, in order to reduce thickness, the quantum dot diffuser plate in this embodiment can be considered as having quantum dot material doped into the polarization diffusion layer 1121 in the above embodiment, giving it multiple functions. In traditional display systems, achieving color conversion, polarization, and diffusion functions usually requires the use of different optical components, such as quantum dot films, polarizers, and diffuser plates, which leads to structural complexity and increased costs. The quantum dot polarization diffuser plate 1123 integrates these three functions into one component, reducing the number of components and assembly complexity, and lowering costs. Simultaneously, the synergistic effect between these functions can better optimize the color, polarization, and distribution characteristics of light, improving the color reproduction, contrast, and uniformity of the displayed image.

[0081] In an embodiment of the light source assembly 11, if 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 regular LED and a lens.

[0082] MiniLED chips are small in size, typically ranging from tens to hundreds of micrometers. This small size allows more chips to be integrated into a second LCD screen of the same area, offering advantages such as small size, high brightness, and high contrast, resulting in a clearer and more detailed display.

[0083] Please see Figure 6 , Figure 6 This is a schematic diagram of a fourth structure of the backlight module provided in an embodiment of this application. In the combination of a conventional LED and a lens, the conventional LED is a blue LED 1111, and the lens 1112 is disposed on the blue LED 1111. The lens 1112 mainly plays the role of light path control. The lens 1112 is usually made of optical-grade materials, such as glass or plastic, and its surface has undergone special optical design to refract and reflect the light emitted by the LED, thereby changing the propagation direction and distribution range of the light. Compared with miniLED chips, the combination of conventional LEDs and lenses has the advantages of low cost and flexible light path control.

[0084] Please see Figure 7 , Figure 7 This is a schematic diagram of the fifth structure of the backlight module provided in the embodiments of this application.

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

[0086] Please see Figure 8 , Figure 8 This is a schematic diagram of the sixth structure of the backlight module provided in the embodiments of this application.

[0087] A fifth embodiment of the light source assembly 11: The polarization assembly 112 includes a polarizing lens 1124, which is disposed on the light-emitting side of the light-emitting unit 111. This polarizing lens 1124 can be made of PMMA (polymethyl methacrylate) doped with nanoparticles exhibiting birefringence. PMMA possesses excellent optical transparency, mechanical properties, and processing performance, making it a commonly used optical material. Birefringence refers to a material having different refractive indices for light with different polarization directions. By rationally designing the type, size, and distribution of nanoparticles, the polarizing lens 1124 can selectively transmit or focus light with a specific polarization direction, thereby achieving a polarization function. The doped birefringent nanoparticles endow the lens with a special polarization function. These nanoparticles are consistent with the nanoparticles in the above embodiments in terms of function and material, and will not be described in detail here.

[0088] Therefore, the polarizing lens 1124 is based on the principle of optical refraction, and its surface usually has a specific curvature or optical structure. When light is incident on the polarizing lens 1124, the light will be refracted on the lens surface, which has the function of optical path control. The polarizing lens 1124 can also adjust the light to polarized light.

[0089] The backlight module 10 also includes a light-diffusing layer 13, which is disposed between the polarizing lens 1124 and the first liquid crystal screen 12 to homogenize the distribution of polarized light. The polarized light emitted from the polarizing lens 1124 may have uneven intensity or inconsistent direction. The light-diffusing layer 13, through scattering and refraction of light, makes the light more evenly distributed in space, avoiding localized over-brightness or under-brightness, and improving the brightness and color uniformity of the displayed image.

[0090] The homogenizing layer 13 can also possess polarization-maintaining properties. Specifically, the homogenizing layer 13 can achieve polarization-maintaining properties by doping a PMMA layer with birefringent nanoparticles. The birefringence effect of the nanoparticles allows the homogenizing layer 13 to maintain the polarization state of light while homogenizing it. The homogenizing layer 13 can also achieve polarization-maintaining properties using materials such as polyimide (PI) or triacetyl cellulose (TAC). Materials such as polyimide and triacetyl cellulose inherently possess a certain degree of optical anisotropy, which can maintain the polarization state of light to a certain extent.

[0091] In a 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 polarizing lens 1124, the light source assembly 11 emits white polarized light, which is then used by the subsequent first liquid crystal screen 12.

[0092] In a fifth embodiment of the light source assembly 11, in some other cases, when the light-emitting unit 111 emits blue light, quantum dot material can also be disposed in the polarizing lens 1124 to convert part of the blue light into red and green light, which are then mixed to form white polarized light, which is then used by the subsequent first liquid crystal screen 12.

[0093] Please see Figure 9 , Figure 9 This is a schematic diagram of the structure of the display device provided in the embodiments of this application.

[0094] This application also provides a display device, which has wide applicability and can be applied to various product forms such as televisions, monitors, flat panels or advertising walls.

[0095] The display device includes a backlight module 10 and a second liquid crystal display (LCD). The backlight module 10 can be the same as the backlight module 10 in the above embodiment, providing necessary light to the second LCD and forming zoned backlight. The second LCD is located on the light-emitting side of the backlight module 10, further modulating the light to present the final image. The two work together to achieve the display function.

[0096] The polarization direction of the incident light polarizer on the second LCD screen is consistent with the polarization direction of the light emitted from the backlight module 10. In optical principles, when the polarization direction of the incident light is consistent with the transmission axis 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 aligning the polarization directions, it is ensured that the polarized light emitted from the backlight module 10 passes through the incident light polarizer of the second LCD screen to the maximum extent, greatly reducing light loss, improving light utilization, and thus enhancing the brightness and energy efficiency of the display device.

[0097] 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 displayed on the second LCD screen. The RGB three-color light emitted by the first LCD screen 12 is the backlight used by the display screen, realizing pixel-level RGB three-color light. Compared with ordinary multi-zone RGB backlight, the embodiments of this application can provide a far greater number of zones than ordinary RGB backlight. More zones mean that different areas in the image can be more accurately corresponded, and more detailed adjustments to brightness and color can be achieved. For example, ordinary RGB backlight may only have dozens or hundreds of zones, while the number of zones in the backlight module 10 of this application may be several times or even tens of times that.

[0098] When displaying complex images, more partitions can better adapt to the brightness changes in different areas of the image, avoiding local over-brightness or under-brightness, and making the image more uniform and natural.

[0099] During use, ordinary RGB backlighting may experience brightness decay and color shift due to factors such as aging of the light-emitting unit 111, requiring algorithmic compensation. However, the embodiments of this application, through precise zone control and pixel-level color adjustment, can adjust brightness and color in real time without relying on algorithmic compensation, thus avoiding the errors and instabilities that algorithmic compensation may introduce.

[0100] In the first LCD screen 12, the red sub-filter area 1221, the green sub-filter area 1222, and the blue sub-filter area 1223 are arranged in an array to give the backlight module 10 a first resolution. For example, in a simple array, the red, green, and blue sub-filter areas may be arranged in the order of RGBRGB... to form a periodic color distribution.

[0101] The primary resolution of the backlight module 10 is determined by the arrangement density and distribution of the red, green, and blue sub-filter areas. The primary resolution directly reflects the precision of the first LCD screen 12 in color control; specifically, it is the number of areas per unit area that can independently control color.

[0102] The second LCD screen has a second resolution. The second resolution of the second LCD screen is the pixel resolution of the second LCD screen itself, which determines the level of detail of the image that the second LCD screen can display, that is, the number of pixels 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 areas of the backlight module 10 are arranged at a density of 200 groups per inch (first resolution), while the pixel density of the second LCD screen is 400 pixels per inch (second resolution). This indicates that the first LCD screen 12 may have slightly lower precision in color control than the second LCD screen in displaying image details. Although this resolution difference leads to a slight reduction in image quality, the image quality of the embodiments in this application is still far superior to that of ordinary multi-zone RGB schemes.

[0104] For example, conventional multi-zone RGB schemes often suffer from noticeable problems such as color deviation, color bleeding, and low contrast due to factors such as a small number of zones and insufficient color control. However, the embodiments of this application, through a carefully designed filter array arrangement and reasonable resolution settings, achieve effective cost control while ensuring a certain level of image quality.

[0105] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0106] In the description of this 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 number of technical features indicated. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features.

[0107] The backlight module and display device provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

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

2. The backlight module according to claim 1, characterized in that, The light source assembly includes a light-emitting unit and a polarization component. The light-emitting unit is used to emit light from the light source, and the polarization component is disposed on the light-emitting side of the light-emitting unit. The polarization component is used to convert the light from the light source into polarized light.

3. The backlight module according to claim 2, characterized in that, The light-emitting unit is a blue light source, and 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, characterized in that, The light-emitting unit is a miniLED chip; or, the light-emitting unit includes a blue LED and a lens, with the 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, and the polarization component includes a quantum dot polarization diffuser plate, which is disposed on the light-emitting side of the blue light source.

6. The backlight module according to claim 2, characterized in that, The polarization component includes a polarizing lens, which is disposed on the light-emitting side of the light-emitting unit.

7. The backlight module according to claim 6, characterized in that, It also includes a light-homing layer, which is disposed between the polarizing lens and the first liquid crystal screen to homogenize the distribution of the polarized light.

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

9. The backlight module according to any one of claims 1 to 7, characterized in that, It also includes a polarizer, which is disposed on the light-emitting side of the first liquid crystal 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 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 the side of the liquid crystal layer away from the color filter and is used to drive the liquid crystal layer.

11. A display device, characterized in that, include: A backlight module, wherein the backlight module is the backlight module according to any one of claims 1 to 10; The second LCD screen is 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 LCD screen is consistent with the polarization direction of the polarized light emitted from the backlight module.

12. The display device according to claim 11, characterized in that, The red sub-filter area, green sub-filter area, and blue sub-filter area are arranged in an array to give the backlight module a first resolution; the second LCD screen has a second resolution; and the first resolution is less than or equal to the second resolution.

Images