Backlight module and manufacturing method therefor, and display device

Abstract

A backlight module and a manufacturing method therefor, and a display device. A certain proportion of a red dye is arranged in an optical component of the backlight module to increase the proportion of red light in the backlight module, actively causing a red shift phenomenon in the color points of the backlight module; moreover, the ratio of red phosphor to green phosphor in a high-color-gamut LED is adjusted, and the proportion of green light is appropriately increased, thereby achieving the correction of the color points of a screen body; an increase in the proportion of the green phosphor in the high-color-gamut LED can not only improve the luminous efficiency of the LED and the thermal reliability, but can also increase the upper limit value of a driving forward current, making the high-color-gamut LED more advanced than a traditional white-light high-color-gamut LED; and by means of the principles above, scheme matching can be carried out on the basis of requirements to achieve the effect of improving the brightness of the backlight module.

Description

Backlight module, its manufacturing method and display device

[0001] Priority information

[0002] This application claims priority and benefits to patent application No. 202411999820.6, entitled "Backlight Module and Display Device", filed with the China National Intellectual Property Administration on December 31, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of backlight module technology, and in particular to a backlight module, its manufacturing method and display device. Background Technology

[0004] High color gamut displays produce more vibrant and vivid images, closer to the true colors of nature, making them more popular in the market. Traditional high color gamut displays, with a color gamut value of NSTC1931 typically between 80% and 85%, achieve this by adding KSF red phosphor and β-sialon green phosphor to the light-emitting diode (LED), in a ratio of approximately 5:1 to 10:1. However, KSF red phosphor itself has low excitation efficiency, producing less excitation light and more heat dissipation, which easily leads to cracking of the LED phosphor and subsequent failure. Therefore, backlight modules equipped with KSF high color gamut LEDs must use a lower current scheme to ensure LED reliability, but this reduces display brightness.

[0005] To improve the brightness of a display device, it is often necessary to add an optical gain film, which is expensive and provides only a limited increase in brightness. Therefore, a more cost-effective high color gamut module solution is needed to enhance the product's market competitiveness. Summary of the Invention

[0006] The purpose of this application is to provide a backlight module, its manufacturing method and display device, which aims to improve the color gamut of the display device, improve the luminous efficiency and thermal reliability of light-emitting diodes (LEDs), and increase the upper limit of the driving forward current.

[0007] To achieve the above objectives, as a first aspect of this application, a backlight module is provided, including a light-emitting diode (LED) and an optical component; the optical component is provided with a red dye; the LED includes a blue LED chip, a bracket having a cavity, and a phosphor adhesive filler, the blue LED chip being located within the cavity and disposed at the bottom of the cavity, and the phosphor adhesive filler covering the blue LED chip; the phosphor adhesive filler includes red phosphor and green phosphor in a mass ratio of 1:1 to 5:1.

[0008] In some embodiments, the red dye satisfies at least one of the following: the red dye is doped within the optical component; the red dye is coated on the light-emitting surface of the optical component.

[0009] In some embodiments, the red dye comprises 1%-5% of the mass of the optical component.

[0010] In some embodiments, the red dye includes one or more of carmine, phthalocyanine red, and iron oxide red.

[0011] In some embodiments, the red phosphor comprises a fluoride red phosphor, and the green phosphor comprises a nitride green phosphor.

[0012] In some embodiments, the optical component is provided with a bubble structure.

[0013] In some further embodiments, the phosphor adhesive filler includes silicone, red phosphor, and green phosphor, wherein the mass ratio of the silicone to the total mass of the phosphor is 1:1 to 5:1, and the mass ratio of the red phosphor to the green phosphor is 1:1 to 5:1.

[0014] In some embodiments, the backlight module is a side-lit backlight module, the optical component includes a light guide plate, and the light-emitting diode is disposed at one end of the light guide plate.

[0015] In some embodiments, the backlight module is a direct-lit backlight module, and the optical component includes a lens disposed on the light-emitting side of the light-emitting diode.

[0016] In some embodiments, the optical component includes at least one of a light guide plate, a lens, a reflector, a diffuser, and an optical film.

[0017] In some embodiments, the optical film includes at least one of a diffusion film, a brightness enhancement film, a diffusion-prism composite film, a microlens-prism composite film, a prism-prism composite film, and a reflective polarizing brightness enhancement composite film.

[0018] As a second aspect of this application, a display device is provided, including a liquid crystal panel and the backlight module described in this application.

[0019] As a third aspect of this application, a method for fabricating a backlight module is provided, for fabricating any of the aforementioned backlight modules, the method comprising:

[0020] A light-emitting diode (LED) is formed, comprising a blue LED chip, a support having a cavity, and a phosphor adhesive filler. The blue LED chip is located within the cavity and disposed at the bottom of the cavity, and the phosphor adhesive filler covers the blue LED chip. The phosphor adhesive filler comprises red phosphor and green phosphor, and the mass ratio of the red phosphor to the green phosphor is 1:1 to 5:1. An optical component is formed on the light-emitting side of the LED, and the optical component is provided with a red dye.

[0021] In some embodiments, the steps of forming the optical component and the red dye include: coating the light-emitting surface of the optical component with a liquid red dye; or, mixing and melting the raw material of the optical component with the raw material of the red dye; granulating the mixed and melted raw material; and mixing the granulated raw material with the raw material of the optical component, melting and cooling it to form the optical component with a predetermined shape.

[0022] In some embodiments, the step of mixing the granulated raw material with the raw material of the optical component further includes: mixing a foaming agent into the granulated raw material.

[0023] In the technical solution of this application, a certain proportion of red dye is set in the optical components of the backlight module to increase the proportion of red light in the backlight module and actively cause a red shift phenomenon in the color point of the backlight module. At the same time, the ratio of red phosphor to green phosphor in the high color gamut LED is adjusted to appropriately increase the proportion of green light and achieve visible screen color point correction. The increase in the proportion of green phosphor in the high color gamut LED can not only improve the luminous efficiency of the LED and improve thermal reliability, but also increase the upper limit of the driving forward current, which is more advanced than traditional white high color gamut LEDs. Using the above principles, the solution can be matched according to the requirements to achieve the effect of improving the brightness of the backlight module and achieve an ultimate cost design solution. Attached Figure Description

[0024] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application.

[0025] Figure 1(A) is a schematic diagram of the structure of a conventional LED, and Figure 1(B) is a schematic diagram of the structure of an LED in the embodiment of this application;

[0026] Figure 2 shows the optical spectrum of the backlight module without red dye and with red dye.

[0027] Figure 3(A) is a CIE1931 color gamut coordinate system diagram of a backlight module with red dye in the optical components, and Figure 3(B) is a CIE1931 color gamut coordinate system diagram of a backlight module with red dye in the optical components and the ratio of red phosphor to green phosphor in the LED adjusted at the same time.

[0028] Figure 4 shows the optical spectrum of the backlight module with the green phosphor ratio unchanged and the backlight module with the green phosphor ratio increased.

[0029] Figure 5(A) is a schematic diagram of a bubble structure set in the light guide plate of a side-lit backlight module, and Figure 5(B) is a schematic diagram of a bubble structure set in the lens of a direct-lit backlight module.

[0030] Figure 6 shows the L50 values ​​of LED lamps with different mass ratios of red and green phosphors.

[0031] Figure 7 shows the excitation efficiency of LEDs with different mass ratios of red and green phosphors.

[0032] Figure 8 shows a schematic diagram of a display device including a side-lit backlight module;

[0033] Figure 9 shows a schematic diagram of a display device including a direct-lit backlight module.

[0034] Explanation of reference numerals: 1. Housing; 101. Light outlet; 102. Back plate; 1021. Side plate; 1022. Bottom plate; 103. Middle frame; 104. Bending section; 2. Circuit board; 3. Light-emitting diode; 301. Blue light chip; 302. Support with storage cavity; 303. Phosphor adhesive filler; 4. Light guide plate; 401. First bubble structure; 5. Reflector; 501. Clearance hole; 6. Lens; 601. Second bubble structure; 7. Diffuser plate; 8. Optical film; 9. Liquid crystal panel; 10. Heat dissipation medium; 11. Adhesive. Detailed Implementation

[0035] This application discloses a backlight module and display device. Those skilled in the art can refer to the content of this document and appropriately improve the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this application. The product described in this application has been described through preferred embodiments. Those skilled in the art can obviously make modifications or appropriate changes and combinations to the product described herein without departing from the content, spirit, and scope of this application to implement and apply the technology of this application. Obviously, the described embodiments are only some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without creative effort are within the scope of protection of this application.

[0036] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this article are only used to explain the relative positional relationship and movement of the components in a specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0037] In this document, unless otherwise expressly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0038] Furthermore, the technical solutions of the various embodiments of this application can be combined with each other, but only if they are feasible to those skilled in the art. If a combination of technical solutions contradicts each other or cannot be implemented, it should be considered that such a combination does not exist and is not within the scope of protection claimed in this application. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0039] In this document, relational terms such as “first” and “second”, “step 1” and “step 2”, and “(1)” and “(2)” are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. Moreover, embodiments and features described herein can be combined with each other without conflict.

[0040] The following provides a further description of a backlight module and display device provided in this application.

[0041] Traditional high color gamut backlight modules are generally divided into edge-lit backlight modules and direct-lit backlight modules. In edge-lit backlight modules, high color gamut LED strips are placed on the side of the module. A light guide plate converts the point light surface of the LEDs into a surface light source. Then, through the brightness enhancement and diffusion effects of optical films such as brightness enhancement films and diffusion films, a uniform surface light source is provided to the LCD panel. In direct-lit backlight modules, high color gamut LED strips are placed at the bottom of the module. An optical lens expands the highly collimated LED light into a beam with a divergence angle of about 150°. Then, through the brightness enhancement and diffusion effects of diffuser plates and optical films, a uniform surface light source is provided to the LCD panel. Regardless of the type of backlight module, in order to avoid the defect of excessive heat dissipation of KSF red phosphor in LED strips, the driving forward current is reduced as a means of compensation. At the same time, the brightness is supplemented by increasing the number of LEDs and stacking optical films. However, this solution significantly increases the cost and increases the reliability risk.

[0042] Based on the aforementioned technical problems of traditional backlight modules, in the first aspect of this application, a backlight module is provided, comprising a light-emitting diode (LED) and optical components; the optical components are provided with a red dye; the LED comprises a blue LED chip, a bracket having a cavity, and a phosphor adhesive filler, the blue LED chip being located within the cavity and disposed at the bottom of the cavity, and the phosphor adhesive filler covering the blue LED chip; the phosphor adhesive filler comprises red phosphor and green phosphor, the mass ratio of which is not higher than 5:1.

[0043] Referring to Figure 1, the blue LED chip 301 in the LED 3 is located within a support 302 with a cavity and is disposed at the bottom of the cavity. Phosphor adhesive filler 303 covers the blue LED chip 301. In some embodiments of this application, the support 302 with the cavity is cup-shaped, and the phosphor adhesive filler 303 covers the blue LED chip 301 and fills the entire cavity. In the LED 3 of this application embodiment, the mass ratio of red phosphor to green phosphor in the phosphor adhesive filler 303 is no higher than 5:1. Compared to the mass ratio of red phosphor to green phosphor of 5:1 to 10:1 in traditional high color gamut LEDs, the embodiments of this application increase the proportion of green phosphor in the LED and reduce the proportion of red phosphor. Since green phosphor has a higher excitation efficiency than red phosphor, the heat dissipation of the LED beads in the embodiments of this application is reduced. This not only improves the overall reliability of the LED but also increases the driving current, thereby increasing brightness, simplifying the optical film configuration, and reducing module costs. On the other hand, the optical components in the backlight module of this application are set with red dye, resulting in an overabundance of red light. If a traditional high color gamut white LED is used in the backlight module, it is difficult to achieve the standard white field color point because traditional high color gamut white LEDs are mainly composed of red phosphors. However, the LEDs in the embodiments of this application have increased the proportion of green phosphors, thereby generating more green light and enabling screen color point correction.

[0044] The optical components in the backlight module provided in this application include any component capable of controlling the transmission and processing of light, such as at least one of light guide plates, lenses, reflective sheets, diffuser plates, and optical films. The optical films include, but are not limited to, at least one of diffuser films, brightness enhancement films, diffuser-on-prism composite films (DOP), micro-lens-on-prism composite films (MOP), prism-on-prism composite films (POP), and cycloclic olefin polymer reflective polarizer composite films (COP).

[0045] The optical components in this application can directly increase the proportion of red light in the light spectrum emitted by the backlight module by setting a red dye, as shown in Figure 2. Compared with a backlight module without red dye (a conventional backlight module), the backlight module with red dye (the backlight module in this application) has a higher peak of red light at a wavelength of 610nm. Using the CIE 1931 color coordinate system as a reference, the color coordinates (x, y) of the pure white field of the display screen will drift towards the red color coordinates (0.67, 0.33). The color coordinates deviating from the standard pure white field are (0.28, 0.29), as shown in Figure 3(A). However, due to the adjustment of the phosphor ratio of the high color gamut LED beads in this application, namely reducing the proportion of red phosphor and increasing the proportion of green phosphor, the color coordinates (x, y) of the display screen shift towards the green color coordinates (0.21, 0.71), as shown in Figure 3(B). This achieves the color coordinates of the pure white field of the display screen to be (0.28, 0.29), which is consistent with the color coordinates of the standard pure white field. It should be noted that, under normal circumstances, (0.28, 0.29) is the color coordinate of the standard pure white field in the CIE1931 coordinate system, which is applicable to most display products. However, different needs may require special pure white field color coordinates, such as (0.27, 0.28), (0.28, 0.31), etc. This application uses the standard pure white field color coordinates of (0.28, 0.29) as an example for explanation.

[0046] When the backlight module in this embodiment is working, the blue LED chip 301 emits blue light. The phosphor adhesive filler 303, including red and green phosphors, is excited by the blue light to generate red and green light. Compared to traditional high color gamut white LEDs, the LED in this embodiment has a significantly increased proportion of green phosphor, resulting in a corresponding increase in the intensity of green light in the emitted spectrum. A schematic diagram of the backlight module spectrum is shown in Figure 4. As can be seen from Figure 4, compared to a backlight module with an unadjusted green phosphor proportion (a conventional backlight module), the peak of the 530nm green light in the backlight module with an increased green phosphor proportion (the backlight module in this embodiment) is significantly enhanced. When the blue light and the generated red and green light pass through the optical components containing red dye, the redshift phenomenon caused by the red dye can be corrected, thereby achieving a standard pure white field.

[0047] The excitation efficiency of green phosphor is much higher than that of red phosphor. Therefore, increasing the proportion of green phosphor in LED can significantly increase the light intensity of the green band of the screen, thereby improving the overall brightness. Based on this principle, the proportion of green phosphor in LED can be appropriately increased, and the proportion of red pigment in optical components can be increased simultaneously. This can achieve a standard pure white field while also significantly improving the brightness of the screen.

[0048] In another aspect of this application, the blue light-emitting diode 3 (LED 3) includes, but is not limited to, a gallium nitride blue light-emitting diode; the phosphor adhesive filler 303 includes silicone, red phosphor, and green phosphor. To ensure reliability, the mass ratio of silicone to total phosphor is 1:1-5:1, such as 1:1, 2:1, 3:1, 4:1, 5:1, etc.; in some embodiments of this application, the red phosphor includes fluoride red phosphor, such as KSF (K2SiF). 6+ The red phosphor and the green phosphor include nitride green phosphors, such as nitride β-sialon green phosphor. In some other embodiments of this application, the mass ratio of red phosphor to green phosphor is greater than or equal to 1:1 and less than or equal to 5:1, for example 1:1, 2:1, 3:1, 4:1, 4.9:1, 5:1, etc., or the mass ratio of red phosphor to green phosphor is greater than or equal to 1:1 or less than 5:1.

[0049] In another aspect of this application, the red dye is uniformly doped within the optical component, or the red dye is uniformly coated on the light-emitting surface of the optical component, or the red dye is uniformly doped not only within the optical component but also uniformly coated on the light-emitting surface of the optical component. The further the red dye is disposed within the optical component or on the light-emitting surface from the liquid crystal panel, the better the light mixing effect and the better the overall effect. For example, the red dye is disposed within the light guide plate or on the light-emitting surface in an edge-lit backlight module, or within the lens and diffuser plate of at least one of them in a direct-lit backlight module, or on the light-emitting surface of another.

[0050] In some embodiments of this application, the optical component incorporates a bubble structure, such as a micron-sized bubble structure. The bubble structure creates a significant difference in refractive index between the optical component and air, causing light energy to be frequently refracted, reflected, and totally internally reflected at the bubble interface, thereby increasing the optical path and improving the light mixing effect. During this process, the backlight energy frequently comes into contact with the red dye, significantly enhancing the redshift effect and making the light output from the optical component more uniform. The bubble structure in the optical component can be achieved by adding a foaming agent to the raw materials during the fabrication of the optical component. The foaming agent can be an inorganic foaming agent (ammonium carbonate, sodium bicarbonate, etc.) or an organic foaming agent (azo, nitroso). The mass percentage of the foaming agent in the raw materials for fabricating the optical component is 3‰-8‰. In some embodiments of this application, sodium bicarbonate is selected as the foaming agent.

[0051] Referring to Figure 5(A), multiple micron-sized first bubble structures 401 are provided in the light guide plate 4 of the side-lit backlight module. Optical films 8 and reflective sheets 5 can be respectively provided on the upper and lower sides of the light guide plate 4. Referring to Figure 5(B), multiple micron-sized second bubble structures 601 are provided in the lens 6 of the direct-lit backlight module. The lens 6 covers the periphery of the light-emitting diode 3, and the light-emitting diode 3 is mounted on the circuit board 2. The refractive index of the light guide plate and lens is about 1.6, while the refractive index of air is about 1.0. Due to the large difference in refractive index, light energy will be frequently refracted, reflected, and totally internally reflected at the bubble interface, thereby increasing the optical path and improving the light mixing effect.

[0052] In some embodiments of this application, the red dye accounts for 1%-5% of the mass of the optical component, such as 1%, 2%, 3%, 4%, 5%, etc. Less than 1% cannot achieve a significant color shift effect, while more than 5% will result in an over-biased color shift, making it impossible to correct the color by adjusting the phosphor ratio of the light-emitting diode.

[0053] In some embodiments of this application, the red dye includes carmine and phthalocyanine red (tetrahydroquinoline diacridone C). 20 H 12 One or more of N2O2 and iron oxide red.

[0054] In some embodiments of this application, coating the light-emitting surface of an optical component with red dye can be achieved by preparing the red dye into a liquid material and uniformly coating it on the light-emitting surface, while doping the interior of an optical component with red dye can be achieved by mixing the red dye with the raw material of the optical component, granulating it, and then preparing it into an optical component.

[0055] In other embodiments of this application, optical components uniformly doped with red dye are obtained by referring to the following method:

[0056] The raw materials for preparing optical components and red dye are mixed and melted uniformly. The melting temperature is between the melting point of the optical component raw materials and the melting point of the red dye. This facilitates the uniform distribution of the red dye in the molten optical component raw materials. Granulation is then performed first, followed by mixing with the optical component raw materials (a foaming agent can be added simultaneously if a bubble structure is required). The processes of feeding, melting, cooling and molding, thickness monitoring, and defect monitoring are repeated to obtain an optical component with red dye. This embodiment of the application, through the process of granulation before optical component preparation, ensures the uniform distribution of red dye in the optical component, avoiding uneven distribution phenomena such as agglomeration that lead to subjective defects and optical data deviations.

[0057] In other embodiments of this application, the following description is further provided using the example of a red dye, phthalocyanine red, disposed within a light guide plate:

[0058] To ensure the uniform distribution of phthalocyanine red, raw material granulation is required first: The light guide plate raw material, polymethyl methacrylate (PMMA), and phthalocyanine red raw material are mixed evenly and then fed into the screw conveyor at 180℃-200℃ for melting. During this process, PMMA melts, while the melting point of phthalocyanine red (around 400℃) remains unaffected, resulting in a uniform distribution of phthalocyanine red within the molten PMMA. The molten mixture is then extruded, cooled, and cut into micron- to millimeter-sized particles. By repeatedly mixing these PMMA and phthalocyanine red particles with pure PMMA particles, and performing the feeding, melting, cooling, molding, thickness monitoring, and defect monitoring processes, a light guide plate incorporating the red dye can be obtained.

[0059] The preparation process of red dye is based on other optical components such as lenses, optical films, and diffusers. For example, after the lens is prepared, a layer of red dye is uniformly coated on its light-emitting surface. When preparing optical films and diffusers, red dye can be mixed with organic plastic and granulated. Finally, depending on the need, organic plastic can be added or not added for feeding, melting, cooling and molding, thickness monitoring, defect monitoring and other steps, so as to obtain the corresponding optical films and diffusers doped with red dye.

[0060] The aforementioned process for incorporating red dyes into optical components is cost-effective and simple. Furthermore, given that optical components such as light guides and lenses are made of organic plastics such as polystyrene (PS), polymethyl methacrylate (PMMA), styrene-methyl methacrylate copolymer (MS), and polycarbonate (PC), phthalocyanine red, due to its superior stability, is a preferred red dye.

[0061] In some embodiments of this application, the light decay of LEDs under different ratios of red and green phosphors is tested by setting different mass ratios. The normal maximum current value If of a traditional high color gamut white LED is also measured. MAX It is generally set at 650mA, while the normal maximum current value of traditional ordinary color gamut white LEDs is If MAXHowever, the current can be set between 850mA and 1A. The reason for the difference is that traditional high color gamut white LEDs have a high KSF red phosphor ratio, but low excitation efficiency and large heat dissipation. If driven by a large current, it is easy to cause abnormal heat dissipation and stress cracking failure of the phosphor. The backlight module provided in this application fully optimizes the ratio of KSF red phosphor to β-sialon green phosphor. Appropriately reducing the KSF red phosphor ratio can significantly improve the heat dissipation of LED beads, thereby increasing the current drive value. As shown in Figure 6, with a fixed forward current value of If = 800mA, the light decay test of high color gamut LED beads with different ratios is carried out under the traditional experimental conditions of 85℃ / 85% humidity. The time value when the brightness decays to 50% is recorded and defined as the LED lifetime value, i.e., L50. The data is shown in Table 1 below. The industry standard for LED lifetime is L50 / 30000H (Typ.), that is, the brightness decays to 50% of the initial value after 30000H.

[0062] Table 1

[0063] Combining the results in Figure 6 and Table 1, it is clear that as the proportion of red phosphor decreases, the light decay of LEDs slows down and the reliability is improved accordingly.

[0064] In some embodiments of this application, the excitation efficiency of LEDs under different ratios of red and green phosphors was tested by setting different mass ratios, and the results are shown in Figure 7. Figure 7 clearly shows that the excitation light intensity at the same current varies significantly depending on the ratio of KSF red phosphor to β-sialon green phosphor. As the proportion of KSF red phosphor decreases and the proportion of β-sialon green phosphor increases, the excitation light intensity of the LED increases accordingly. It can also be seen that when the proportion of KSF red phosphor is absolutely dominant (e.g., 5:1-10:1), the LED reaches its peak excitation efficiency at a current of 500-600mA. Further increasing the current does not significantly improve brightness, and more electrical energy is converted into heat, affecting reliability. When the ratio of KSF red phosphor to β-sialon green phosphor is roughly equal, the LED still exhibits improved excitation efficiency at 800mA.

[0065] Therefore, appropriately reducing the proportion of KSF red phosphor in high color gamut LEDs is beneficial to improving the reliability and excitation efficiency of the LED chips. When this technology is applied to backlight modules, it can highlight a very obvious brightness improvement effect, thereby reducing the number of LED chips and the configuration of films, thus achieving efficiency improvement and cost reduction.

[0066] In another aspect of this application, the backlight module is a side-lit backlight module, and the optical components include a light guide plate, with a light-emitting diode disposed at one end of the light guide plate.

[0067] Referring to Figure 8 as an example, the side-lit backlight module includes: a housing 1, a circuit board 2, a light-emitting diode (LED) 3, a light guide plate 4, a reflector 5, and an optical film 8. The housing 1 forms a cavity with a light outlet 101. The circuit board 2 is disposed on one side of the cavity. The LED 3 is disposed on the side of the circuit board 2 facing away from the cavity. A schematic diagram of the LED 3 is shown in Figure 1, including a blue LED chip 301, a support 302 with a cavity, and a phosphor adhesive filler 303. The blue LED chip 301 is located inside the cavity and at the bottom of the cavity, and the phosphor adhesive filler 303 covers the blue LED chip 301. 303 includes red phosphor and green phosphor, with a mass ratio of red phosphor to green phosphor of 1:1 to 5:1; red dye is doped in the light guide plate 4 and disposed in the accommodating cavity, the light-incident side of the light guide plate 4 is disposed corresponding to the light-emitting diode 3, and the light-emitting side of the light guide plate 4 is disposed corresponding to the light-emitting port 101; the reflective sheet 5 is disposed on the side of the light guide plate 4 away from the light-emitting port 101 and abuts against the light guide plate 4; the optical film 8 is disposed on the side of the light guide plate 4 close to the light-emitting port 101 and abuts against the light guide plate 4.

[0068] In some embodiments of this application, the housing 1 includes a back plate 102 and a middle frame 103. The back plate 102 includes a side plate 1021 and a bottom plate 1022. The side plate 1021 and the bottom plate 1022 are directly connected. The middle frame 103 is spaced apart from the bottom plate 1022 and connected through the side plate 1021. A light outlet 101 is provided on the middle frame 103. The circuit board 2 is mounted on the side plate 1021.

[0069] In some embodiments of this application, the reflector 5 abuts against the base plate 1022, and the side of the optical film 8 is connected to the edge of the middle frame 103 near the light outlet 101 by an adhesive 11 (e.g., a strip).

[0070] In some embodiments of this application, a heat dissipation medium 10, such as a heat dissipation aluminum strip, is partially or completely provided between the circuit board 2 and the back plate 102 or between the reflector 5 and the back plate 102.

[0071] In the aforementioned side-lit backlight module, the housing 1 forms a cavity, and a light outlet 101 communicating with the cavity is provided on the housing 1 at a position corresponding to the cavity. The light-emitting diode 3 is disposed on the side of the light guide plate 4, which is either the left or right side of the light guide plate 4. The light guide plate 4 is disposed in the cavity, and the side of the light guide plate 4 closer to the light-emitting diode 3 is the light-inlet side, and the side of the light guide plate 4 closer to the light outlet 101 is the light-outlet side.

[0072] During operation, circuit board 2 provides power to LED 3, which emits blue light. The phosphor adhesive filler 303 in LED 3 increases the proportion of green phosphor and reduces the proportion of red phosphor. The resulting light includes system blue light as well as green and red light excited by the blue light. Then, a light guide plate 4 converts the point light source of LED 3 into a surface light source. The light guide plate 4 is doped with red pigment. After mixing, the various colors of light achieve a standard white field color point, significantly improving screen brightness. The brightness gain and diffusion effects of reflective sheet 5 and optical film 8 provide a uniform surface light source for LCD panel 9. Utilizing this principle, not only can LED luminous efficiency and thermal reliability be improved, but the upper limit of the driving forward current can also be increased. Compared to traditional white high color gamut LEDs, this is more advanced and allows for customized solutions to achieve improved backlight module brightness, resulting in a cost-effective design.

[0073] In another aspect of this application, the backlight module is a direct-lit backlight module, and the optical components include a lens disposed on the light-emitting side of the light-emitting diode. Furthermore, the optical components also include one or more of a diffusion film, a diffusion plate, and a reflective sheet.

[0074] Referring to Figure 9 as an example, the direct-lit backlight module includes: a housing 1, a circuit board 2, a reflector 5, a light-emitting diode 3, a lens 6, a diffuser 7, and an optical film 8. The housing 1 encloses a cavity, and the cavity has a light-emitting port 101. The circuit board 2 is disposed on the bottom of the cavity. The reflector 5 is disposed on the side of the circuit board 2 away from the bottom of the cavity and extends along the sidewall of the cavity to the sidewall of the light-emitting port 101. The reflector 5 on the circuit board 2 has a clearance hole 501. The light-emitting diode 3 is disposed in the clearance hole 501 and mounted on the circuit board 2. A schematic diagram of the structure of the light-emitting diode 3 is shown in Figure 1, including... The device comprises a blue LED chip 301, a support 302 with a storage cavity, and a phosphor adhesive filler 303. The blue LED chip 301 is located inside the storage cavity and is disposed at the bottom of the storage cavity. The phosphor adhesive filler 303 covers the blue LED chip 301. The phosphor adhesive filler 303 includes red phosphor and green phosphor, and the mass ratio of red phosphor to green phosphor is 1:1 to 5:1. A lens 6 is doped with red dye and covers the periphery of the light-emitting diode 3. A diffuser plate 7 is disposed at the light outlet 101 of the storage cavity, and the light-emitting diode 3 is disposed perpendicular to the diffuser plate 7. An optical film 8 is disposed on the side of the diffuser plate 7 away from the housing 1 and abuts against it.

[0075] In some embodiments of this application, the edge of the housing 1 is bent toward the diffuser plate 7 to form a bend 104.

[0076] In the above-mentioned direct-lit backlight module, the housing 1 is arranged to form a cavity. A light outlet 101 communicating with the cavity is opened on the housing 1 at the position corresponding to the cavity. The backlight composed of the light-emitting diode 3 and the lens 6 is set at the bottom of the cavity and on the circuit board 2 in the clearance hole 501. The light-emitting diode 3 is set perpendicular to the diffuser plate 7 in order to achieve the best light emission effect.

[0077] During operation, circuit board 2 provides power to LED 3, which emits blue light. The phosphor adhesive filler 303 in LED 3 increases the proportion of green phosphor and reduces the proportion of red phosphor. The resulting light includes system blue light as well as green and red light excited by the blue light. Lens 6, which contains red pigment, expands the highly collimated LED light into a beam with a divergence angle of approximately 150°. The various colors of light are mixed to achieve a standard white field, significantly improving screen brightness. Further brightness gain and diffusion effects from reflector 5, diffuser 7, and optical film 8 provide a uniform surface light source for LCD panel 9. Utilizing this principle, without changing the number of LEDs or the backlight module architecture, increasing the LED driving current significantly improves the backlight module brightness without incurring additional costs. This allows for a module solution with optimal cost-effectiveness, which is highly advantageous for designs requiring high brightness and high energy efficiency in backlight modules.

[0078] In another aspect of this application, a display device is provided, including a liquid crystal panel 9 and any of the backlight modules provided in this application.

[0079] In some embodiments of this application, the display device includes a liquid crystal panel 9 and the aforementioned side-lit backlight module. A structural schematic is shown in FIG8. Based on the aforementioned side-lit backlight module, the liquid crystal panel 9 is disposed over the light outlet 101 and abuts against the housing 1. The abutment method includes, but is not limited to, using an adhesive 11 (e.g., glue strip) for connection.

[0080] In some other embodiments of this application, the display device includes a liquid crystal panel 9 and the aforementioned direct-lit backlight module. A structural schematic is shown in FIG9. Based on the aforementioned direct-lit backlight module, the liquid crystal panel 9 is disposed over the light outlet 101 and abuts against the bent portion 104. The abutment method includes, but is not limited to, using an adhesive 11 (e.g., a strip of glue) for connection.

[0081] Based on the technical principles of the present application, it is known that the optical components of the backlight module are equipped with red dye to induce a red shift, which can improve the color gamut of the display device. Simultaneously, to correct the (x, y) color coordinates to the standard pure white field color coordinates (e.g., x = 0.28, y = 0.29), the phosphor ratio of the high color gamut LED beads is adjusted, i.e., the proportion of red phosphor is increased, and the proportion of green phosphor is increased, shifting the (x, y) color coordinates of the display device towards the green region. Furthermore, under the same blue light chip excitation, green phosphor has a higher excitation efficiency than red phosphor. As the proportion of green phosphor in the LED increases, the brightness level of the LED can be increased simultaneously, and the heat dissipation of the LED beads is reduced. This not only improves the overall reliability of the LED but also increases the driving current, thereby increasing brightness, simplifying the optical film configuration, and reducing module costs.

[0082] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A backlight module, wherein, The device includes a light-emitting diode (LED) and optical components; the optical components are provided with a red dye; the LED includes a blue LED chip, a support with a cavity, and a phosphor adhesive filler, the blue LED chip being located within the cavity and disposed at the bottom of the cavity, and the phosphor adhesive filler covering the blue LED chip; the phosphor adhesive filler includes red phosphor and green phosphor, and the mass ratio of the red phosphor to the green phosphor is 1:1 to 5:

1.

2. The backlight module according to claim 1, wherein, The red dye satisfies at least one of the following: The red dye is doped into the optical component; The red dye is coated on the light-emitting surface of the optical component.

3. The backlight module according to claim 2, wherein, The red dye comprises 1%-5% of the mass of the optical component.

4. The backlight module according to claim 1, wherein, The red dye includes one or more of carmine, phthalocyanine red, and iron oxide red.

5. The backlight module according to claim 1, wherein, The red phosphor includes fluoride red phosphor, and the green phosphor includes nitride green phosphor.

6. The backlight module according to claim 1, wherein, The optical component incorporates a bubble structure.

7. The backlight module according to any one of claims 1-6, wherein, The phosphor adhesive filler includes silicone, red phosphor, and green phosphor, wherein the mass ratio of the silicone to the total mass of the phosphor is 1:1 to 5:1, and the mass ratio of the red phosphor to the green phosphor is 1:1 to 5:

1.

8. The backlight module according to claim 6, wherein, The backlight module is a side-lit backlight module, and the optical components include a light guide plate, with the light-emitting diode disposed at one end of the light guide plate.

9. The backlight module according to claim 6, wherein, The backlight module is a direct-lit backlight module, and the optical components include a lens, which is disposed on the light-emitting side of the light-emitting diode.

10. The backlight module according to claim 1, wherein, The optical components include at least one of a light guide plate, a lens, a reflector, a diffuser plate, and an optical film.

11. The backlight module according to claim 10, wherein, The optical film includes at least one of the following: diffusion film, brightness enhancement film, diffusion-prism composite film, microlens-prism composite film, prism-prism composite film, and reflective polarizing brightness enhancement composite film.

12. A display device, wherein, It includes a liquid crystal panel and a backlight module as described in any one of claims 1-9.

13. A method for fabricating a backlight module, used to fabricate the backlight module as described in any one of claims 1-11, the fabrication method comprising: A light-emitting diode (LED) is formed, comprising a blue LED chip, a support having a cavity, and a phosphor adhesive filler. The blue LED chip is located within the cavity and disposed at the bottom of the cavity, and the phosphor adhesive filler covers the blue LED chip. The phosphor adhesive filler comprises red phosphor and green phosphor, and the mass ratio of the red phosphor to the green phosphor is 1:1 to 5:

1. An optical component is formed on the light-emitting side of the light-emitting diode, and the optical component is provided with a red dye.

14. The method for manufacturing a backlight module according to claim 13, wherein, The steps of forming the optical component and the red dye include: A liquid red dye is coated on the light-emitting surface of the optical component; Alternatively, the raw material of the optical component can be mixed and melted with the raw material of the red dye; Granulation of the mixed and melted raw materials; The granulated raw materials are mixed with the raw materials of the optical component, melted and cooled to form the optical component with a set shape.

15. The method for manufacturing a backlight module according to claim 14, wherein, The step of mixing the granulated raw material with the raw material of the optical component further includes: A foaming agent is mixed into the granulated raw material.

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