Light-emitting assembly, preparation method thereof, backlight module and display device

Abstract

The application discloses a light-emitting assembly and a preparation method thereof, a backlight module and a display device, and relates to the technical field of display. The application discloses a light-emitting assembly preparation method, which comprises the following steps: mixing a light-emitting material and an encapsulating colloid to obtain a colloid mixture; applying the colloid mixture to a light-emitting surface of a light-emitting chip to form a prefabricated encapsulating body; and performing centrifugal treatment on the prefabricated encapsulating body at a centrifugal temperature, wherein the centrifugal treatment comprises the following steps: centrifuging at a first rotating speed for a first time length, then increasing the rotating speed to a second rotating speed, and centrifuging for a second time length; performing solidification treatment on the prefabricated encapsulating body after the centrifugal treatment to obtain the light-emitting assembly, wherein the solidification treatment comprises the following steps: solidifying at a first solidification temperature for a third time length, and solidifying at a second solidification temperature for a fourth time length, and the second solidification temperature is higher than the first solidification temperature. The application aims to eliminate the problems of the existence of a sudden physical interface in a light-emitting layer and structural cracking and light efficiency loss caused thereby caused by a traditional centrifugal process.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a light-emitting component and its preparation method, a backlight module, and a display device. Background Technology

[0002] In LED (light-emitting diode) display devices, semiconductor light-emitting chips are typically used in conjunction with a light-emitting layer (i.e., a phosphor layer) to achieve white light or light output at a specific color temperature. The light-emitting layer is composed of phosphors dispersed in a light-transmitting encapsulant. The particle size distribution, spatial arrangement, and filling density of the phosphors inside the layer directly determine the color temperature consistency, light output efficiency, and reliability of the device.

[0003] Currently, phosphors typically undergo precise grading and screening before use, retaining only narrow-distribution powders with a particle size range ≤1.0 and discarding excessively coarse and fine particles to avoid uncontrollable process issues caused by large differences in sedimentation rates in wide-distribution powders. However, precise grading and screening results in the waste of a large amount of virgin powder, leading to generally low powder utilization rates and significantly increasing the procurement and processing costs of phosphors. Meanwhile, to achieve more uniform color temperature consistency, the industry commonly uses centrifugation to prepare the luminescent layer, utilizing centrifugal force to force phosphors to settle and rearrange in a colloid. However, in traditional centrifugation processes, phosphors of different particle sizes have significant differences in sedimentation rates in a constant centrifugal force field. Larger particles rapidly settle and accumulate on the chip surface, while smaller particles are instantly pushed to the colloid surface, forming a bilayer structure with abrupt changes in particle size distribution, step changes in filling density, and a distinct physical interface. This abrupt interface easily becomes a stress concentration point during thermal cycling tests, leading to cracking and peeling; simultaneously, the abrupt change in refractive index on both sides of the interface generates optical reflection loss, reducing light extraction efficiency. Summary of the Invention

[0004] The main objective of this application is to provide a light-emitting component and its preparation method, a backlight module and a display device, which aims to eliminate the problems of abrupt physical interface changes in the light-emitting layer caused by traditional centrifugation processes and the resulting structural cracking and light efficiency loss.

[0005] To achieve the above objectives, embodiments of this application provide a method for fabricating a light-emitting component, the method comprising: The luminescent material is mixed with the encapsulating colloid to obtain a colloidal mixture; The colloidal mixture is applied to the light-emitting surface of the light-emitting chip to form a pre-encapsulated body; The pre-packaged body is centrifuged at a centrifugation temperature, wherein the centrifugation process includes: centrifuging at a first rotation speed for a first duration, then increasing the rotation speed to a second rotation speed and centrifuging for a second duration; The pre-packaged body after centrifugation is cured to obtain a light-emitting component. The curing process includes curing for a third time at a first curing temperature and curing for a fourth time at a second curing temperature, wherein the second curing temperature is higher than the first curing temperature.

[0006] In one embodiment, the conditions for the centrifugation treatment include at least one of the following: The centrifugation temperature is 40–50 °C; The first rotational speed is 750-850 rpm, and the first duration is 25-35 s; The second rotational speed is 2800–3200 rpm, and the second duration is 90–150 s; Angular acceleration is 0.8–1.2 rad / s². 2 .

[0007] In one embodiment, the conditions for the curing process include at least one of the following: The first curing temperature is 55–65 °C, and the third curing time is 20–30 min; The second curing temperature is 115–125 °C, and the fourth curing time is 55–65 min.

[0008] In addition, to achieve the above objectives, this application also proposes a light-emitting component, which is manufactured by the method described above.

[0009] In one embodiment, the light-emitting component includes: LED chip; A light-emitting layer is disposed on the light-emitting side of the light-emitting chip, the light-emitting layer comprising an encapsulating colloid and a light-emitting material distributed in the encapsulating colloid along the light-emitting direction.

[0010] In one embodiment, the light-emitting layer satisfies at least one of the following: In the light-emitting layer, the particle size of the light-emitting material gradually decreases along the light-emitting direction; In the light-emitting layer, the filling rate of the light-emitting material gradually decreases along the light-emitting direction; The effective refractive index of the light-emitting layer gradually decreases along the light-emitting direction; The scattering ability of the light-emitting layer gradually increases along the light emission direction.

[0011] In one embodiment, the light-emitting layer satisfies at least one of the following: In the light-emitting layer, the D50 particle size of the light-emitting material on the side closer to the light-emitting chip is 20-28 μm, and the D50 particle size of the light-emitting material on the side farther from the light-emitting chip is 3-6 μm; In the light-emitting layer, the D50 particle size of the light-emitting material varies with a unit thickness of 0.4–0.8 μm / μm along the light-emitting direction; The thickness of the light-emitting layer is 80~120 μm, and the thickness of the continuously gradient region of the filling rate of the light-emitting material accounts for more than 75% of the thickness of the light-emitting layer; In the light-emitting layer, the filling rate of the light-emitting material on the side closer to the light-emitting chip is 35%–45%, and the filling rate of the light-emitting material on the side farther from the light-emitting chip is 5%–15%. The equivalent refractive index of the light-emitting layer varies by ≤0.002 per micrometer along the light-emitting direction; The scattering coefficient of the light-emitting layer on the side away from the light-emitting chip is 3.2 to 4.5 times that of the light-emitting layer on the side closer to the light-emitting chip; In the light-emitting layer, the thermal quenching temperature of the light-emitting material on the side closest to the light-emitting chip is ≥190℃.

[0012] In one embodiment, the luminescent material includes: YAG phosphor, chlorosilicate phosphor, TAG phosphor, Ca-α-SiAlON phosphor, β-Ca2SiO4:Eu 2+ Phosphor, BaSi2O2N2:Eu 2+ At least one of phosphor, β-SiAlON phosphor, KSF phosphor, CASN phosphor, and red quantum dot.

[0013] In addition, to achieve the above objectives, this application also proposes a backlight module, which includes the light-emitting component as described above, or the light-emitting component manufactured by the method described above.

[0014] In addition, to achieve the above objectives, this application also proposes a display device, which includes a light-emitting component as described above, or a light-emitting component manufactured by the method described above, or a backlight module as described above.

[0015] One or more technical solutions proposed in this application have at least the following technical effects: A method for preparing a light-emitting component is provided, which involves mixing a light-emitting material with an encapsulating colloid to obtain a colloidal mixture, and applying the colloidal mixture to the light-emitting surface of a light-emitting chip to form a pre-encapsulated body. Furthermore, by centrifuging at a centrifugal temperature, the viscosity of the transparent encapsulating colloid is reduced, decreasing the settling resistance of the light-emitting material in the colloid. This allows light-emitting materials of different particle sizes to migrate and redistribute fully in the centrifugal force field. Simultaneously, this application employs a segmented variable-speed centrifugation method, first centrifuging at a first speed for a first duration, then increasing to a second speed for a second duration. Through a linear, slow-increase process within a defined range, the difference in settling rates between light-emitting materials of different particle sizes is gradually reduced, effectively avoiding the abrupt stratification phenomenon caused by sudden settling under conventional fixed-speed centrifugation conditions. Thus, large-particle-size light-emitting materials naturally settle and accumulate near the light-emitting chip, while small-particle-size light-emitting materials slowly float and accumulate away from the light-emitting surface of the chip, forming a continuous gradient structure without physical boundaries. Furthermore, during the curing process of the pre-encapsulated body after centrifugation, a pre-curing treatment at a first curing temperature is first performed to bring the translucent encapsulating colloid to a gel state, initially locking the sedimentation distribution state of the luminescent material formed during centrifugation. Then, a main curing treatment at a second curing temperature is performed to completely cross-link and cure the encapsulating colloid. This effectively avoids thermal migration and secondary rearrangement of the luminescent material due to Brownian motion during subsequent high-temperature curing, preventing the continuous gradient structure formed by centrifugation from failing due to high-temperature curing, thus ensuring the integrity and stability of the continuous gradient structure and producing a light-emitting component. The light-emitting component prepared by the above method has a gradient structure within its luminescent layer, where the filling density and equivalent refractive index of the luminescent material are synchronously and continuously gradually distributed without abrupt physical interfaces from the side near the luminescent chip to the side away from the luminescent chip. Based on the formation of this continuous gradient structure, the luminescent layer eliminates problems such as thermal cycling cracking and detachment, optical reflection loss caused by abrupt changes in interface refractive index, and large apparent angular aberrations caused by the presence of abrupt physical interfaces in traditional centrifugal double-layer processes, significantly improving the structural reliability and optical consistency of the light-emitting component. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a conventional light-emitting component; Figure 2 This is a flowchart illustrating the method for fabricating a light-emitting component according to an embodiment of this application; Figure 3 This is a schematic diagram of the structure of the light-emitting component involved in the embodiments of this application; Figure 4 This describes the gradient variation trend of the depth direction parameters of the light-emitting layer involved in the embodiments of this application; Figure 5 This is a schematic diagram of the backlight module in an embodiment of this application; Figure 6 This is a schematic diagram of the display device in an embodiment of this application.

[0017] Explanation of reference numerals in the attached figures 10. Light-emitting component; 11. Support; 12. Protective layer; 13. Light-emitting chip; 14. Emissive layer; 141. Lower fluorescent layer; 142. Upper fluorescent layer; 143. Layer interface; 100. Backlight module; 110. Back panel; 120. Reflective film; 130. Diffuser plate; 140. Optical functional film; 200. Display panel; 300. Display device.

[0018] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0020] The embodiments of this application are hereby disclosed in detail with appropriate reference to the accompanying drawings. However, unnecessary details may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of actually identical structures may be omitted. This is to avoid making the following description unnecessarily lengthy and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0021] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for a specific parameter, it is also expected that ranges of 60~110 and 80~120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this application, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0~5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0022] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0023] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, preferably sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, if the method may also include step (c), it means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0024] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the technical solution of this application is further described below in conjunction with the accompanying drawings and embodiments. However, this application is not limited to the listed embodiments, but should also include any other well-known modifications within the scope of the claims made in this application.

[0025] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0026] In conventional technology, LED (light-emitting diode) light-emitting components 10 typically employ, for example... Figure 1The structure shown mainly includes a support 11, a light-emitting chip 13 (e.g., a blue light chip) disposed in the support 11, a protective layer 12 covering the light-emitting surface of the light-emitting chip 13, and a light-emitting layer 14 (i.e., a phosphor layer). The light-emitting layer 14 is composed of phosphor dispersed in a transparent encapsulating colloid, used to convert at least part of the excitation light emitted from the light-emitting chip 13 into emitted light of different wavelengths, which, after mixing, output white light or light of a specific color temperature. Currently, the preparation of the light-emitting layer 14 in the LED light-emitting component 10 mainly employs two methods: a uniform powder mixing process or a centrifugal double-layer process.

[0027] For the uniform powder mixing process, conventional phosphors such as YAG, nitride, fluoride, and silicate phosphors must be precisely graded and sieved to remove oversized and ultrafine particles, retaining only powder within a narrow particle size range for use. All powder from the beginning and end of the sieving process is discarded. After mixing the sieved narrow-segment powder with silica gel, the phosphor particles are randomly distributed within the adhesive layer. After encapsulation, the high-temperature heating area near the chip is prone to contamination with small-diameter phosphor particles with weak heat resistance. When the LED is powered on for extended periods, these small-diameter phosphor particles undergo lattice deformation under sustained high temperatures, exacerbating thermal quenching and leading to accelerated light decay and color temperature drift. Conversely, if large-diameter phosphor particles accumulate on the light-emitting surface away from the chip, their small surface area and poor light scattering ability result in excessively concentrated light emission, easily causing localized bright spots and color shifts on the screen. Therefore, this process cannot simultaneously achieve both thermal stability and optical uniformity.

[0028] For the centrifugal two-layer process, the sieved phosphor is mixed with silica gel and centrifuged at a constant speed. Due to the difference in particle settling rate, phosphors of different particle sizes spontaneously aggregate to form a two-layer structure with clear upper and lower boundaries (i.e., the lower phosphor layer 141 and the upper phosphor layer 142). The composition and powder bulk density of the two layers are inconsistent, forming a flat and rigid physical interface (i.e., the delamination interface 143). When the display product undergoes high and low temperature alternation or humid heat aging, due to the difference in the thermal expansion coefficients of silica gel and phosphor, stress is concentrated at the delamination interface 143 and cannot be uniformly released. After long-term use, gaps are prone to appear at the interface, which can lead to delamination cracking or even failure of the adhesive. In addition, the different powder densities of the upper and lower layers cause a sudden change in the equivalent refractive index of the corresponding adhesive layer at the interface. When light travels to the delamination interface 143, a large amount of reflection and refraction loss occurs, reducing the overall light extraction efficiency of the device.

[0029] Based on this, the first aspect of the present application provides a method for fabricating a light-emitting component 10, referring to... Figure 2 The method for preparing the light-emitting component 10 includes the following steps: Step S10: Mix the luminescent material with the encapsulating colloid to obtain a colloidal mixture.

[0030] In one feasible embodiment, the luminescent material is uniformly mixed with the encapsulating colloid to obtain a colloidal mixture, so as to facilitate the preparation of the luminescent layer 14.

[0031] Optionally, the light-emitting material is used to perform wavelength conversion on the excitation light emitted from the light-emitting chip 13.

[0032] Alternatively, the luminescent material can be a phosphor.

[0033] Optionally, the luminescent material includes: YAG phosphor, chlorosilicate phosphor, TAG phosphor, Ca-α-SiAlON phosphor, β-Ca2SiO4:Eu 2+ Phosphor, BaSi2O2N2:Eu 2+ At least one of phosphor, β-SiAlON phosphor, KSF phosphor, CASN phosphor, and red quantum dot.

[0034] Optionally, the above-mentioned luminescent material can be used alone, or multiple luminescent materials can be mixed in proportion according to the target color temperature and color rendering index requirements. This application does not limit this.

[0035] Optionally, the encapsulating colloid is a light-transmitting adhesive used to disperse and carry the luminescent material, and forms a dense luminescent layer 14 after curing.

[0036] Optionally, the material of the encapsulating colloid may include at least one of the following: silicone, epoxy resin, modified polyurethane, and acrylate transparent resin.

[0037] Optionally, the luminescent materials do not need to undergo precise grading and sieving before mixing; that is, luminescent materials with a wide native particle size range can be directly added to the formulation.

[0038] For example, phosphor and transparent silicone are added to a mixing container at a preset mass ratio. The phosphor is uniformly dispersed in the silicone by mechanical or centrifugal stirring, followed by vacuum degassing to remove air bubbles introduced by stirring. Thus, the colloidal mixture is a slurry in which phosphor is uniformly dispersed in a transparent encapsulating colloid. Unlike traditional processes that require separate preparation and processing of coarse and fine powders, this embodiment directly uses phosphor with a wide particle size range and silicone in a single mixing process. This eliminates the need for particle size classification and screening, and avoids the waste of raw materials caused by classification and screening.

[0039] Step S20: Apply the colloidal mixture to the light-emitting surface of the light-emitting chip 13 to form a pre-made encapsulation.

[0040] In one feasible embodiment, the colloidal mixture is applied to the light-emitting surface of the light-emitting chip 13 to form a pre-packaged body.

[0041] Optionally, the light-emitting chip 13 is a solid-state semiconductor light-emitting element.

[0042] Optionally, the light-emitting chip 13 is a blue light chip, which plays a crucial role in converting electrical energy into light energy. It is primarily made of semiconductor materials, releasing energy through the recombination of electrons and holes to generate photons, which in turn emit visible light or electromagnetic radiation of other wavelengths. Commonly used semiconductor materials for blue light chips include gallium arsenide (GaAs), gallium phosphide (GaP), and gallium nitride (GaN), which emit blue light of specific wavelengths based on the electroluminescence effect of PN junctions.

[0043] Optionally, the light-emitting chip 13 is an LED chip or a mini LED chip.

[0044] Optionally, the light-emitting chip 13 is a flip chip. A flip chip has the active side of the chip facing down and directly contacting the packaging substrate. This structure allows the heat generated by the chip to be quickly conducted to the substrate and dissipated through a heat dissipation system. Compared with traditional packaging technology, flip chip packaging does not require wire bonding, and the direct connection between the chip and the substrate greatly shortens the heat conduction path and reduces thermal resistance.

[0045] Optionally, refer to Figure 3 The light-emitting component 10 provided in this embodiment of the application is further provided with a support 11. The support 11 serves as a carrier substrate, and its material can be selected from at least one of polyphthalamide, polycyclohexanediol terephthalate, epoxy molding compound, or liquid crystal polymer, but is not limited thereto. A cup-shaped receiving groove is formed in the support 11, and the light-emitting chip 13 is disposed at the bottom of the cup-shaped receiving groove.

[0046] Optionally, a protective layer 12 may be pre-formed on the light-emitting surface side of the light-emitting chip 13. The protective layer 12 is used to cover and protect the pads, electrodes and other devices in the light-emitting component 10, and can also stabilize the light-emitting chip 13.

[0047] Optionally, the material of the protective layer 12 includes at least one of silicone, epoxy resin and polyurethane resin.

[0048] Optionally, the thickness of the protective layer 12 can be greater than the height of the light-emitting chip 13, thereby completely enclosing the light-emitting chip 13 and providing all-round physical and chemical protection for the light-emitting chip 13, preventing moisture, dust and other contaminants from entering, and improving long-term reliability and stability.

[0049] Optionally, the thickness of the protective layer 12 can be less than or equal to the height of the light-emitting chip 13, thus partially enclosing the light-emitting chip 13. The light-emitting layer 14 located on the light-emitting side of the protective layer 12 can directly contact the light-emitting chip 13, so that the light emitted by the light-emitting chip 13 can be directly transmitted to the light-emitting layer 14, reducing reflection loss caused by additional optical interfaces, such as the protective layer 12, thereby improving light output efficiency.

[0050] Optionally, the application method can be a dispensing process, that is, the adhesive mixture is quantitatively dispensed into the cup-shaped receiving groove of the support 11 by dispensing equipment, so that the adhesive mixture fills the light-emitting surface of the light-emitting chip 13.

[0051] Optionally, the dispensing process can be point-to-point and quantity-based dispensing, controlling the dispensing amount to initially define the thickness range of the subsequent light-emitting layer 14. After dispensing, the adhesive mixture spreads naturally under the action of surface tension, filling at least a portion of the space in the cup-shaped receiving groove of the support 11.

[0052] Understandably, after the colloidal mixture is applied, the luminescent material in the mixture remains uniformly dispersed in the liquid silicone and has not yet settled or stratified. At this point, the internal structure of the pre-encapsulated body is homogeneous, and the luminescent material does not yet exhibit differential distribution in concentration or particle size along the thickness direction.

[0053] Step S30: Centrifuge the pre-packaged body at a centrifugation temperature.

[0054] The centrifugation process includes: centrifuging at a first speed for a first duration, then increasing the speed to a second speed and centrifuging for a second duration.

[0055] In one feasible embodiment, the pre-packaged body is placed in a centrifuge and centrifuged at a first speed for a first duration at a centrifugation temperature. Then, the speed is increased to a second speed and centrifuged for a second duration.

[0056] In one feasible embodiment, the centrifugation temperature is 40–50 °C; for example, the centrifugation temperature is 40 °C, 41 °C, 42 °C, 43 °C, 44 °C, 45 °C, 46 °C, 47 °C, 48 °C, 49 °C, 50 °C, etc.

[0057] In this embodiment, by controlling the centrifugation temperature within 40–50 °C, the viscosity of the encapsulating colloid is reduced by increasing the temperature (i.e., the low-temperature viscosity reduction effect), thereby reducing the sedimentation resistance of the luminescent material in the encapsulating colloid. This allows luminescent materials of different particle sizes to migrate and redistribute fully in the centrifugal force field. If the centrifugation temperature is too low, the viscosity of the encapsulating colloid is too high, and the migration resistance of the luminescent material in the colloid increases significantly. This results in incomplete effective sedimentation and classification within the centrifugation time, and some small-particle-size luminescent materials may even fail to migrate to the surface due to excessive resistance, ultimately maintaining a uniformly distributed homogeneous state. If the centrifugation temperature is too high, the viscosity of the encapsulating colloid is too low, resulting in an excessively fast sedimentation rate. This makes it impossible to form a controllable gradient distribution, and at higher temperatures, the luminescent material may not be locked into the colloid during subsequent centrifugation, making it prone to premature sedimentation due to a sudden drop in colloid viscosity, thus compromising process stability. Therefore, controlling the centrifugation temperature within the above range can suppress premature sedimentation while ensuring sufficient migration rate of the luminescent material, providing a suitable process window for subsequent segmented centrifugation.

[0058] In one feasible embodiment, the first rotational speed is 750-850 rpm, and the first duration is 25-35 s; for example, the first rotational speed is 750 rpm, 760 rpm, 780 rpm, 790 rpm, 800 rpm, 810 rpm, 820 rpm, 830 rpm, 840 rpm, 850 rpm, etc.; and the first duration is 25 s, 26 s, 27 s, 28 s, 29 s, 30 s, 31 s, 32 s, 33 s, 34 s, 35 s, etc.

[0059] In this embodiment, during the first rotational speed stage, a relatively low centrifugal force is used to induce differential sedimentation displacement of the luminescent material in the colloid. Luminescent materials of different particle sizes are driven by Stokes sedimentation in a low centrifugal field. Larger particles have a slightly higher sedimentation rate than smaller particles, but the difference is not yet significantly amplified. This achieves initial separation and rearrangement of particles of different sizes, providing directional drive and initial displacement for the natural sedimentation and enrichment of larger particles on the chip side and the slow upward floating and enrichment of smaller particles on the light-emitting side. If the first rotational speed is too low, the centrifugal force is insufficient to overcome the viscous resistance of the colloid to the luminescent material, making it difficult for particles of different sizes to generate initial differential sedimentation displacement, thus weakening the particle size grading effect in the subsequent acceleration stage. If the first rotational speed is too high, the difference in particle sedimentation rate in the low centrifugal field is already significant, leading to abrupt particle size stratification before subsequent acceleration, making a smooth gradient impossible. In the first duration phase, the initial constant speed period of 25s to 35s allows the luminescent material to obtain sufficient kinetic energy for accelerated migration. On the other hand, under the low temperature and viscosity reduction conditions, the large-diameter luminescent material begins to initially settle towards the chip side, and the small-diameter luminescent material begins to initially float towards the light-emitting side, forming an initial particle size distribution separation trend. If the first duration is too short, the luminescent material is accelerated before it has established a differentiated settling trend, and the continuity of particle size classification decreases. If the first duration is too long, at low speed, the large and small particles have already formed a clear layered interface 143, and subsequent speed increases cannot bridge the layered interface 143 into a smooth transition zone.

[0060] In one feasible embodiment, the second rotational speed is 2800–3200 rpm, and the second duration is 90–150 s; for example, the second rotational speed is 2800 rpm, 2850 rpm, 2900 rpm, 2950 rpm, 3000 rpm, 3050 rpm, 3100 rpm, 3150 rpm, 3200 rpm, etc.; and the second duration is 90 s, 95 s, 100 s, 105 s, 110 s, 115 s, 120 s, 125 s, 130 s, 135 s, 140 s, 145 s, 150 s, etc.

[0061] Optionally, large-diameter luminescent materials are rapidly enriched on the side of the light-emitting chip in about 11 seconds to complete the construction of the heat-resistant underlayer, while medium-diameter particles are fully graded in about 80 to 100 seconds to form a continuous gradient filling.

[0062] In this embodiment, during the second rotational speed stage, the centrifugal force is increased to 2800–3200 rpm, causing the luminescent material to continue migrating along the light-emitting direction in an enhanced centrifugal force field. This promotes further orderly rearrangement of the initially separated luminescent materials of varying sizes along the thickness direction. Unlike constant-speed centrifugation, this embodiment increases the speed after the luminescent material has achieved initial differentiated sedimentation displacement, allowing particles of different sizes to gradually complete their spatially ordered arrangement from large to small in a continuously changing centrifugal force field. During the second duration stage, a duration of 90–150 s is used to ensure that the luminescent materials, after accelerated migration, are sufficiently compacted at their respective equilibrium positions, forming a stable continuous gradient structure. This avoids excessively long centrifugation times that could lead to over-compacting particles or secondary agglomeration, affecting the uniformity and gradient stability of the luminescent material distribution within the light conversion layer. Consequently, large-diameter luminescent materials naturally settle and accumulate near the light-emitting chip 13, while small-diameter luminescent materials slowly rise and accumulate on the light-emitting surface away from the light-emitting chip 13, forming a continuous gradient structure without physical boundaries.

[0063] In one feasible embodiment, the angular acceleration of the centrifugal treatment is 0.8–1.2 rad / s². 2 For example, the angular acceleration during centrifugation is 0.8 rad / s². 2 0.9 rad / s 2 1 rad / s 2 1.1 rad / s 2 1.2 rad / s 2 .

[0064] In this embodiment, the increase from the first rotational speed to the second rotational speed during centrifugation is not instantaneous, but rather a linear change over a certain acceleration period. The angular acceleration during this acceleration phase has a crucial impact on the formation of a continuous gradient structure. If the angular acceleration is too small, the enhancement of the centrifugal force field is insufficient to propel the luminescent material sufficiently along the light emission direction within the effective time. Small-diameter particles cannot obtain sufficient upward buoyancy driving force, resulting in incomplete particle size classification. A large proportion of homogeneous mixed regions remain within the light conversion layer, failing to form a complete continuous gradient structure, thus affecting the subsequent construction of scattering and refractive index gradients. If the angular acceleration is too large, the rapid change in the centrifugal force field causes a huge difference in sedimentation rate between large and small-diameter luminescent materials in a very short time. Small-diameter particles are rapidly pushed to the surface, while large-diameter particles are abruptly pressed towards the chip side, forming a cliff-like abrupt change in particle size distribution. This results in a return to the abrupt layered structure of traditional centrifugation processes, making it impossible to achieve a smooth continuous gradient. Therefore, the angular acceleration is controlled between 0.8 and 1.2 rad / s. 2Within this range, the centrifugal force field can be continuously and gradually enhanced during the acceleration phase, resulting in a gradual change in the centrifugal driving force experienced by luminescent materials of different particle sizes. Consequently, under the continuously varying driving force, the luminescent materials gradually complete spatial rearrangement along the thickness direction. Larger particles continuously migrate towards the chip side, while smaller particles continuously migrate towards the light-emitting surface, ultimately forming a smooth gradient structure with a continuous transition in particle size along the thickness direction, rather than the abrupt double-layer structure of traditional centrifugal processes. Simultaneously, the gentle angular acceleration avoids turbulent disturbances or localized agglomeration of particles due to sudden force changes during acceleration, which helps maintain the uniformity and stability of the internal structure of the light conversion layer.

[0065] Optionally, the sedimentation and migration behavior of the luminescent material in a centrifugal field follows Stokes' law of centrifugal sedimentation, and its sedimentation velocity is determined by the following equation: v 离心 = 2(ρ p ρ f )ω 2 Rr 2 / (9μ); Among them, v 离心 ρ is the centrifugal sedimentation velocity of the particles. p ρ is the solid density of the luminescent material. f Let ρ be the density of the liquid encapsulant, ω be the centrifuge angular velocity, R be the radius of gyration, r be the particle radius of the luminescent material, and μ be the dynamic viscosity of the encapsulant. From the above formula, it can be seen that under the same liquid medium environment (i.e., ρ...), f Under the same conditions (i.e., ω and R are the same), the settling velocity of the luminescent material is related to the square of its particle radius (r). 2 The settling velocity of large-diameter luminescent materials is directly proportional to that of small-diameter luminescent materials. Based on this principle, this application implements a segmented centrifugal acceleration strategy to achieve in-depth self-grading of luminescent materials. In the first rotational speed stage, under a lower centrifugal force field, large-diameter luminescent materials achieve a higher settling velocity than small-diameter luminescent materials, migrating towards the chip side first, while small-diameter luminescent materials settle slowly and remain suspended in the upper layer of the colloid, thus forming an initial trend of particle size difference distribution. In the acceleration stage, as the centrifuge angular velocity ω gradually increases, the settling velocity of all particles increases synchronously, but because the settling velocity is directly proportional to ω... 2The settling velocity of large-diameter particles increases much more rapidly than that of small-diameter particles. By controlling the angular acceleration within a specific range, the enhancement of the centrifugal force field changes gradually. Large-diameter particles continuously accelerate and settle closer to the chip side, while small-diameter particles slowly migrate towards the light-emitting surface under a weaker centrifugal driving force, thus further expanding the initial particle size separation trend into a complete particle size gradient distribution. In the second rotational speed stage, under a higher centrifugal force field, particles of each size are fully packed and compacted at their equilibrium positions, forming a smooth particle size gradient structure with a continuous transition from large-diameter particles on the chip side to small-diameter particles on the light-emitting surface. Thus, unlike the instantaneous sudden settling and abrupt stratification caused by excessive differences in settling rates under traditional constant-speed centrifugation conditions, this embodiment of the application, through the coordinated control of low-temperature viscosity reduction and piecewise linear speed change, utilizes the relationship that the settling velocity is proportional to the square of the particle size to gradually amplify the differences in settling displacement of particles of different sizes, achieving smooth and deep self-gradation of powder along the thickness direction of the light conversion layer.

[0066] Step S40: The pre-packaged body after centrifugation is cured to obtain the light-emitting component 10.

[0067] The curing process includes: curing for a third time at a first curing temperature, and curing for a fourth time at a second curing temperature, wherein the second curing temperature is higher than the first curing temperature.

[0068] In one feasible embodiment, the pre-encapsulated body after centrifugation is placed in a curing device and subjected to a two-stage gradient curing process at a first curing temperature and a second curing temperature to crosslink and cure the encapsulated colloid, thereby obtaining the light-emitting component 10. The first curing temperature is a lower temperature, and the second curing temperature is higher than the first curing temperature.

[0069] In one feasible embodiment, the first curing temperature is 55-65 °C, and the third curing time is 20-30 min; for example, the first curing temperature is 55 °C, 56 °C, 57 °C, 58 °C, 59 °C, 60 °C, 61 °C, 62 °C, 63 °C, 64 °C, 65 °C, etc.; and the third curing time is 20 min, 21 min, 22 min, 23 min, 24 min, 25 min, 26 min, 27 min, 28 min, 29 min, 30 min, etc.

[0070] In this embodiment, a two-stage gradient curing strategy is adopted, consisting of pre-curing at a low temperature (55–65 °C) followed by primary curing at a high temperature (115–125 °C). It is understood that after centrifugation, although the luminescent material forms a smooth gradient structure in the encapsulating colloid with a continuous transition from large particle size on the chip side to small particle size on the light-emitting surface along the thickness direction, the encapsulating colloid is still in a liquid or low-crosslinking state, and the spatial position of the luminescent material within the colloid is not yet fixed. If high-temperature curing is performed directly, the viscosity of the encapsulating colloid will decrease sharply during the heating process, and the luminescent material particles in the liquid colloid will undergo random thermal migration driven by thermodynamic Brownian motion, causing the formed gradient structure to be destroyed due to secondary particle rearrangement. To avoid the above situation, this embodiment first performs pre-curing treatment at a lower first curing temperature (55–65 °C): the pre-made encapsulated body is heated to 55–65 °C and held at this temperature for 20–30 minutes. Within this temperature range, the crosslinking reaction of the encapsulating colloid begins but the reaction rate is moderate, and the colloid gradually changes from a liquid state to a gel state. During this process, the encapsulating colloid loses its macroscopic fluidity, and the luminescent material particles are physically anchored in their respective positions by the gel-state colloidal network. The thermal migration ability of the particles in the colloid is significantly suppressed, and the gradient distribution state formed by centrifugation is initially locked. If the first curing temperature is too low, the cross-linking reaction rate of the encapsulating colloid is too slow. Within the 20-30 minute pre-curing time, the colloid cannot form a gel network sufficient to anchor the luminescent material particles. The particles can still migrate freely during subsequent heating, leading to locking failure and destruction of the gradient structure. If the first curing temperature is too high, the cross-linking of the colloid in the pre-curing stage is too intense. On the one hand, it may lead to excessive cross-linking of the encapsulating colloid before the subsequent main curing, affecting the further orderly cross-linking of the colloidal molecular chains in the main curing stage, resulting in incomplete curing or internal stress concentration. On the other hand, the excessively high pre-curing temperature itself will induce particle thermal migration, causing degradation of the gradient structure before locking.

[0071] In one feasible embodiment, the second curing temperature is 115–125 °C, and the fourth curing time is 55–65 min; for example, the second curing temperature is 115 °C, 116 °C, 117 °C, 118 °C, 119 °C, 120 °C, 121 °C, 122 °C, 123 °C, 124 °C, 125 °C, etc., and the fourth curing time is 55 min, 56 min, 57 min, 58 min, 59 min, 60 min, 61 min, 62 min, 63 min, 64 min, 65 min, etc.

[0072] In this embodiment, after the pre-curing treatment described above, the encapsulating colloid has changed from a liquid state to a gel state, and the gradient distribution structure of the luminescent material is initially locked. Based on this, the temperature is raised to 115–125 °C and maintained at this temperature for 55–65 min for primary curing. Under this high-temperature condition, the cross-linking reaction of the encapsulating colloid proceeds completely, and the colloid changes from a gel state to a dense glassy or rubbery state, forming a highly cross-linked three-dimensional network structure. The luminescent material particles are firmly encapsulated in the cross-linked network, and their spatial positions are ultimately fixed. If the second curing temperature is too low, the cross-linking reaction kinetics of the encapsulating colloid are insufficient, and complete cross-linking cannot be achieved within the 55–65 min curing time. Unreacted active groups remain inside the colloid, affecting the density and long-term reliability of the light conversion layer. If the second curing temperature is too high, it may cause thermal degradation or surface oxidation of the luminescent material, leading to a decrease in luminous efficiency. Simultaneously, excessively high curing temperatures may cause thermal deformation of the support 11 material, affecting the structural stability of the luminescent component 10. Therefore, this application embodiment adopts a two-stage curing strategy of low-temperature pre-curing to lock the gradient and high-temperature main curing to fully cross-link the colloid. On the one hand, the low-temperature pre-curing allows the colloid to reach a gel state, effectively locking the smooth gradient structure formed after centrifugation and avoiding gradient failure caused by the secondary migration of the luminescent material due to Brownian motion during the subsequent high-temperature curing process. On the other hand, the high-temperature main curing allows the colloid to fully cross-link the colloid, ensuring that the light conversion layer obtains sufficient mechanical strength and structural stability, thereby achieving simultaneous protection of gradient structure integrity and encapsulation reliability.

[0073] In this embodiment, a method for preparing a light-emitting component 10 is provided. The method involves mixing a light-emitting material with an encapsulating colloid to obtain a colloidal mixture, which is then applied to the light-emitting surface of a light-emitting chip 13 to form a pre-encapsulated body. Centrifugation at a specific temperature reduces the viscosity of the transparent encapsulating colloid, decreasing the settling resistance of the light-emitting material within the colloid. This allows light-emitting materials of different particle sizes to migrate and redistribute fully in the centrifugal force field. Furthermore, this embodiment employs a segmented variable-speed centrifugation method, first centrifuging at a first speed for a first duration, then increasing to a second speed for a second duration. This linear, slow-increase process within a defined range gradually reduces the difference in settling rates between light-emitting materials of different particle sizes, effectively avoiding the abrupt stratification caused by sudden settling under conventional fixed-speed centrifugation conditions. Consequently, large-particle-size light-emitting materials naturally settle and accumulate near the light-emitting chip 13, while small-particle-size light-emitting materials slowly rise and accumulate away from the light-emitting surface of the chip 13, forming a continuous gradient structure without physical boundaries. Furthermore, during the curing process of the pre-encapsulated body after centrifugation, a pre-curing treatment at a first curing temperature is first performed to bring the translucent encapsulating colloid to a gel state, initially locking the sedimentation distribution state of the luminescent material formed by centrifugation; then, a main curing treatment at a second curing temperature is performed to completely cross-link and cure the encapsulating colloid. This effectively avoids thermal migration and secondary rearrangement of the luminescent material due to Brownian motion during subsequent high-temperature curing, preventing the continuous gradient structure formed by centrifugation from failing due to high-temperature curing, thus ensuring the integrity and stability of the continuous gradient structure, and producing the luminescent component 10. The luminescent component 10 prepared by the above method has a gradient structure without abrupt changes in the physical interface formed within its luminescent layer 14, where the filling density and equivalent refractive index of the luminescent material are synchronously and continuously gradually distributed from the side near the luminescent chip 13 to the side away from the light-emitting surface of the luminescent chip 13. Based on the formation of the above continuous gradient structure, the light-emitting layer 14 eliminates the problems caused by the abrupt physical interface in the traditional centrifugal double-layer process, such as thermal cycling cracking and peeling, optical reflection loss caused by abrupt change in interface refractive index, and large visual aberration, which significantly improves the structural reliability and optical consistency of the light-emitting component 10.

[0074] A second aspect of this application provides a light-emitting component 10, which is manufactured by the method described above, referring to... Figure 3 The light-emitting component 10 includes: LED chip 13; The light-emitting layer 14 is disposed on the light-emitting side of the light-emitting chip 13. The light-emitting layer 14 includes an encapsulating colloid and a light-emitting material distributed in the encapsulating colloid along the light-emitting direction.

[0075] In one feasible embodiment, the light-emitting component 10 prepared by the above-described method has a gradient structure formed in its light-emitting layer 14, where the filling density and equivalent refractive index of the light-emitting material are synchronously and continuously gradually distributed without abrupt physical interfaces from the side near the light-emitting chip 13 to the side away from the light-emitting surface of the light-emitting chip 13. Based on the formation of the above-described continuous gradient structure, the light-emitting layer 14 eliminates the problems caused by the presence of abrupt physical interfaces in traditional centrifugal double-layer processes, such as thermal cycling cracking and peeling, optical reflection loss caused by abrupt changes in interface refractive index, and large visual aberration, significantly improving the structural reliability and optical consistency of the light-emitting component 10.

[0076] Optionally, refer to Figure 3 The light-emitting component 10 also includes a support 11, which has a receiving groove. The receiving groove can be a bowl-shaped structure with a trapezoidal cross-section. The light-emitting chip 13, the protective layer 12, and the light-emitting layer 14 are all disposed in the receiving groove, forming a sealed container.

[0077] In one feasible embodiment, the luminescent material includes: YAG phosphor, chlorosilicate phosphor, TAG phosphor, Ca-α-SiAlON phosphor, β-Ca2SiO4:Eu 2+ Phosphor, BaSi2O2N2:Eu 2+ At least one of phosphor, β-SiAlON phosphor, KSF phosphor, CASN phosphor, and red quantum dot.

[0078] Optionally, the D50 particle size of YAG phosphor is 3–28 μm, the D50 particle size of nitride (e.g., Ca-α-SiAlON phosphor, β-SiAlON phosphor, CASN phosphor) is 5–30 μm, the D50 particle size of fluoride (e.g., KSF phosphor) is 0.15–40 μm, and the D50 particle size of silicate (e.g., chlorosilicate phosphor, β-Ca2SiO4:Eu) is 0.5–40 μm. 2+ Phosphor, BaSi2O2N2:Eu 2+ The D50 particle size of the phosphor is 2-25 μm.

[0079] In one feasible implementation, refer to Figure 4 In the light-emitting layer 14, the particle size of the light-emitting material gradually decreases along the light-emitting direction.

[0080] Optionally, in the light-emitting layer 14, the D50 particle size of the light-emitting material on the side closer to the light-emitting chip 13 is 20-28 μm (e.g., particle sizes of 20 μm, 22 μm, 24 μm, 26 μm, 28 μm, etc.), and the D50 particle size of the light-emitting material on the side farther from the light-emitting chip 13 is 3-6 μm (e.g., particle sizes of 3 μm, 4 μm, 5 μm, 6 μm, etc.).

[0081] Optionally, the D50 particle size of the luminescent material varies with a unit thickness of 0.4 to 0.8 μm / μm along the light emission direction (e.g., unit thickness variations of 0.4 μm / μm, 0.5 μm / μm, 0.6 μm / μm, 0.7 μm / μm, 0.8 μm / μm, etc.).

[0082] In this embodiment, based on Stokes' law of centrifugal sedimentation (the settling velocity of particles is proportional to the square of their diameter), large-diameter luminescent materials achieve higher settling velocities in the centrifugal field, preferentially migrating and accumulating towards the bottom layer closer to the light-emitting chip 13. Small-diameter luminescent materials, due to their slower settling velocity, gradually suspend and accumulate on the surface layer of the light-emitting surface, away from the light-emitting chip 13. As the progressively increasing centrifugal force with piecewise linear acceleration intensifies, particles of different sizes are continuously arranged according to their equilibrium positions, forming a continuous particle size gradient distribution with a smooth transition from large particles at the bottom layer to small particles at the surface. Thus, the large-diameter luminescent materials enriched near the high-temperature heat source region of the light-emitting chip 13 possess a more complete lattice structure and higher thermal stability, effectively resisting the thermal quenching effect caused by Joule heating generated during the operation of the light-emitting chip 13, maintaining long-term light output stability. Meanwhile, the small-diameter luminescent materials enriched on the surface layer of the light-emitting surface have a larger specific surface area, increasing the scattering cross-section of light and facilitating uniform light emission.

[0083] In one feasible implementation, refer to Figure 4 In the light-emitting layer 14, the filling rate of the light-emitting material gradually decreases along the light-emitting direction.

[0084] Optionally, the thickness of the light-emitting layer 14 is 80~120 μm, and the thickness of the region with a continuous gradient in the filling rate of the light-emitting material accounts for more than 75% of the thickness of the light-emitting layer 14.

[0085] Optionally, in the light-emitting layer 14, the filling rate of the light-emitting material on the side closer to the light-emitting chip 13 is 35-45% (e.g., 35%, 36%, 38%, 40%, 42%, 44%, 45%, etc.), and the filling rate of the light-emitting material on the side farther from the light-emitting chip 13 is 5-15% (e.g., 5%, 6%, 8%, 10%, 12%, 14%, 15%, etc.).

[0086] In this embodiment, as large-diameter luminescent materials accumulate at the bottom layer and small-diameter luminescent materials rise to the surface, the large-diameter particles at the bottom layer accumulate, and due to the large gaps between the particles, the colloid cannot completely fill the gaps. This results in a high powder packing density but relatively low filling rate. Conversely, the small-diameter particles at the surface layer are densely packed, and the gaps between the particles are fully filled by the colloid. This results in a relatively high powder volume ratio. In reality, due to the continuous action of centrifugal force, the bottom-layer luminescent materials are subjected to stronger centrifugal compaction, resulting in a tighter packing of particles, a lower porosity, and a higher proportion of powder per unit volume (i.e., filling rate). The surface-layer luminescent materials are subjected to weaker centrifugal force, resulting in a looser packing and a lower filling rate. This continuously decreasing filling rate from the bottom layer to the surface along the light emission direction further synergistically influences the gradient construction of refractive index and scattering performance. In the light-emitting layer 14, the high filling rate on the side close to the light-emitting chip 13 forms a continuous heat conduction path and quickly dissipates the heat of the light-emitting chip 13, while the colloid on the surface layer (i.e. the side away from the light-emitting chip 13) has a higher proportion of colloid. The colloid itself has excellent elasticity to buffer temperature stress and prevent the colloid from cracking due to hot and cold cycles.

[0087] In one feasible implementation, refer to Figure 4 The equivalent refractive index of the light-emitting layer 14 gradually decreases along the light-emitting direction.

[0088] Optionally, the equivalent refractive index of the light-emitting layer 14 varies by ≤0.002 per micrometer along the light-emitting direction.

[0089] Optionally, the bulk refractive index of the luminescent material is 1.80~2.00, the refractive index of the encapsulating colloid is 1.41, and then the equivalent refractive index of the encapsulating colloid changes smoothly from about 1.58 at the bottom layer to about 1.45 at the surface layer as the filling rate of the luminescent material changes continuously. The refractive index change per micrometer thickness is ≤0.002, there is no interface with abrupt refractive index change, eliminating interface reflection loss, improving light output, and facilitating brightness improvement.

[0090] In this embodiment, unlike the step change in refractive index at the abrupt interface in the traditional centrifugal double-layer process, the refractive index gradient structure of this application effectively reduces the total internal reflection loss of light at the abrupt refractive index interface and improves the light emission efficiency of the light-emitting component 10.

[0091] In one feasible implementation, refer to Figure 4 In the light-emitting layer 14, the thermal quenching temperature of the light-emitting material on the side closest to the light-emitting chip 13 is ≥190℃.

[0092] Optionally, the quantum efficiency of the luminescent material is ≥92% at 150℃, the heat resistance decreases continuously along the light emission direction, and the temperature distribution of the matching chip gradually decreases from the inside to the outside.

[0093] In one feasible embodiment, the scattering ability of the light-emitting layer 14 gradually increases along the light-emitting direction.

[0094] Optionally, the scattering coefficient of the light-emitting layer 14 on the side away from the light-emitting chip 13 is 3.2 to 4.5 times (e.g., 3.2 times, 3.4 times, 3.6 times, 3.8 times, 4 times, 4.2 times, 2.4 times, 4.5 times, etc.) of the scattering coefficient of the light-emitting layer 14 on the side closer to the light-emitting chip 13.

[0095] In this embodiment, the scattering ability is closely related to the particle size and filling density of the luminescent material. According to the Mie scattering theory, the scattering cross-section is largest and the scattering ability is strongest when the particle size is close to the incident light wavelength. In this application, the particle size of the small-diameter luminescent material enriched on the surface is closer to the blue light wavelength, so its scattering cross-section is much larger than that of the large-diameter particles in the bottom layer. At the same time, the scattering ability gradually increases from the side of the light-emitting chip 13 towards the light-emitting surface, so that the excess blue light emitted in the vertical direction is effectively scattered by the fine powder on the surface, and some blue light is scattered back into the light-emitting layer 14 to excite the phosphor, increasing the probability of blue light being converted into yellow light, thereby suppressing the vertical blue bias phenomenon; while the light emitted at large angles, when passing through the light-emitting layer 14 with gradually enhanced scattering ability, the mixing ratio of blue light and yellow light tends to be consistent at different viewing angles, thereby improving the large-angle yellow bias phenomenon and achieving uniform color temperature across the entire viewing angle. In addition, the gradient distribution of scattering ability can also avoid local light intensity concentration on the light-emitting surface, significantly improve the problem of local bright spots on the screen, and improve the optical uniformity of the backlight module.

[0096] Optionally, the luminescent material can be directly selected from unscreened and unground virgin powder, eliminating the manual compounding process of coarse and fine luminescent materials, increasing the utilization rate by 15-25%, and reducing the cost of powder raw materials per unit by 8-15%.

[0097] Optionally, the large-particle-size, high-heat-resistant luminescent material in the light-emitting layer 14 is enriched in the high-temperature region near the light-emitting chip 13 to suppress powder thermal quenching. In the aging test at 85℃ / 85%RH / 1000h, the LED brightness decay is ≤5%, and the color coordinates Δx and Δy are both ≤0.008.

[0098] Optionally, the equivalent refractive index of the light-emitting layer 14 has a continuous and smooth transition, with no interface reflection loss, which improves the light output efficiency by 8 to 10% compared with traditional LEDs.

[0099] Optionally, the filling density gradient of the luminescent material achieves a gradual change in stiffness from the inside to the outside, balancing the stress of thermal cycling and reducing defects such as colloid cracking and delamination.

[0100] A third aspect of this application provides a backlight module, which includes the light-emitting component 10 as described above.

[0101] Optionally, refer to Figure 5The backlight module 100 includes: The back plate 110 is the basic support structure of the entire backlight module 100. It can be bent in an F-shape to form an accommodating space for installing other components in the backlight module 100. The back plate 110 can provide mechanical support and protect the internal components in the backlight module 100. In the above embodiments, the light-emitting component 10, or the array of light-emitting components 10, is disposed at the bottom of the accommodating space formed by the back plate 110, providing the necessary light source for the backlight module 200. The reflective film 120 is located inside the back panel 110 and is used to reflect light from inside the backlight module 100 back, thereby improving light utilization efficiency. The diffuser plate 130 is located on the light-emitting side of the light-emitting component 10. Its function is to homogenize the light, make the light softer and more uniform, and reduce light spots and shadows. Optical functional film 140 is located on the light-emitting side of the diffuser plate; the optical functional film may include: brightness enhancement film, prism sheet, etc., used to enhance the brightness of light and improve the display effect.

[0102] The beneficial effects of the backlight module provided in this application embodiment are the same as those of the light-emitting component 10 provided in the above embodiment, and other technical features in the backlight module are the same as those disclosed in the method of the above embodiment, and will not be repeated here.

[0103] A fourth aspect of this application provides a display device, which includes: a light-emitting component 10 as described above, or a backlight module as described above.

[0104] Optionally, refer to Figure 6 The display device 300 includes: a backlight module 100 and a display panel 200; The backlight module includes: a back plate 110, which is the basic support structure of the entire backlight module 100. It can be bent in an F-shape to form an accommodating space for installing other components within the backlight module 100. The back plate 110 provides mechanical support and protects the internal components of the backlight module 100. The light-emitting components 10, or an array of light-emitting components 10, are positioned at the bottom of the accommodating space formed by the back plate 110, providing the necessary light source for the backlight module 100. A reflective film 120, located inside the back plate 110, reflects light from inside the backlight module 100 back, improving light utilization efficiency. A diffuser plate 130, located on the light-emitting side of the light-emitting components 10, homogenizes the light, making it softer and more uniform, reducing light spots and shadows. An optical functional film 140, located on the light-emitting side of the diffuser plate, may include a brightness enhancement film, a prism sheet, etc., to enhance light brightness and improve display effects. The display panel 200 is located on the light-emitting side of the optical functional film 140 in the backlight module 100. It is the final display part of the display device and is used to display images and text.

[0105] The beneficial effects of the display device provided in this application embodiment are the same as those of the light-emitting component 10 provided in the above embodiment, and other technical features in the display device are the same as those disclosed in the method of the above embodiment, and will not be repeated here.

[0106] In order to enable those skilled in the art to clearly understand the details and operations of the above embodiments of this application, and to demonstrate the significant improvement in performance of the embodiments of this application, the above technical solutions are illustrated below through multiple embodiments.

[0107] To verify the technical advantages of the embodiments of this application, two sets of mainstream traditional processes in the industry were set as comparative examples, and parallel benchmarking tests were carried out with the light-emitting component 10 of the embodiments of this application. All samples used the same batch of 3030SMC bracket 11, 4848 flip-chip blue light chip, original powder of the same system, the same amount of adhesive and uniform curing parameters, and uniformly completed 85℃ / 85%RH / 1000h damp heat aging and 500 cycles of high and low temperature cycling from -40℃ to 125℃ reliability tests. The six key indicators were compared: initial luminous efficacy (Lm / W), aging light decay, color coordinate drift Δx, color coordinate drift Δy, raw material utilization rate, and colloid cracking defect rate.

[0108] Example 1 A luminescent material (YAG phosphor) is mixed with an encapsulating colloid (silicone) to obtain a colloidal mixture; The colloidal mixture is applied to the light-emitting surface of the light-emitting chip (blue light chip) to form a pre-made package; The pre-packaged body was centrifuged at 46°C. The centrifugation process included centrifuging at 800 rpm for 28 seconds, then increasing the speed to 3000 rpm and centrifuging for X seconds. The pre-packaged body after centrifugation is cured to obtain the light-emitting component. The curing process includes curing at 61°C for 26 min and curing at 118°C for 60 min.

[0109] Example 2 The difference from Example 1 is that the luminescent material is replaced with CASN phosphor.

[0110] Example 3 The difference from Example 1 is that the luminescent material is replaced with KSF phosphor.

[0111] Comparative Example 1 YAG phosphor is precisely graded and sieved to retain narrowly distributed powder particles with a particle size of 8-18 μm. The sieved phosphor is mixed with silica gel and stirred for 15 min, then vacuum degassed for 30 min to obtain a fluorescent colloidal mixture. The fluorescent colloidal mixture is then dispensed onto the light-emitting surface of the blue light chip and cured at 150°C for 4 h to obtain the light-emitting component.

[0112] Comparative Example 2 YAG phosphor is precisely graded and sieved to retain narrowly distributed powder particles with a particle size of 8-18 μm. The sieved phosphor is mixed with silica gel and stirred for 15 min, then vacuum degassed for 30 min to obtain a fluorescent colloidal mixture. The fluorescent colloidal mixture is dispensed onto the light-emitting surface of the blue light chip, centrifuged at a constant speed of 2000 rpm for 10 min at 25 °C, and then cured at 150 °C for 4 h to obtain the light-emitting component.

[0113] The test results are shown in Table 1 below: Table 1

[0114] Based on the above experimental results, it is evident that the two traditional processes have inherent structural defects, resulting in disordered powder mixing and chaotic stress distribution. The double-layer centrifugal process exhibits a rigid delamination interface, with cracking failure rates reaching 5.2% and 8.6% respectively after 500 high and low temperature cycles. The embodiments of this application employ a continuous gradient integrated structure, eliminating physical delamination interfaces and ensuring uniform stress release. The cracking failure rate of these embodiments is ≤0.3%, completely resolving the problems of colloidal cracking and interlayer delamination failure. Furthermore, the embodiments of this application feature an interface-free gradient refractive index structure, completely eliminating interface optical losses. The light extraction efficiency is improved by approximately 6% compared to conventional powder mixing and by 4%–5% compared to traditional double-layer centrifugal processes. After aging, the traditional process exhibits Δx≥0.0024 and Δy≥0.0021, resulting in severe color shift. This process significantly reduces color drift, with Δx≤0.0014 and Δy≤0.0013. Furthermore, in the embodiments of this application, the large-particle-size, high-heat-resistant powder is enriched in the high-temperature region, effectively suppressing powder thermal quenching and lattice degradation. The aging optical decay is only 3.7% to 4.1%, far superior to the 7.8% to 9.2% optical decay level of traditional processes, significantly improving the long-term optical stability and service life of the device. Moreover, the traditional process of precision sieving of powder generates a large amount of waste, with a raw material utilization rate of only 71% to 73%. This application can directly use virgin wide powder and sieving waste, without the need for graded compounding, increasing the raw material utilization rate to 90.5% to 93% and the powder utilization rate to over 15%, significantly reducing raw material procurement and processing costs.

[0115] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the patent protection scope of this application.

Claims

1. A method for preparing a light-emitting component, characterized in that, The method includes: The luminescent material is mixed with the encapsulating colloid to obtain a colloidal mixture; The colloidal mixture is applied to the light-emitting surface of the light-emitting chip to form a pre-encapsulated body; The pre-packaged body is centrifuged at a centrifugation temperature, wherein the centrifugation process includes: centrifuging at a first rotation speed for a first duration, then increasing the rotation speed to a second rotation speed and centrifuging for a second duration; The pre-packaged body after centrifugation is cured to obtain a light-emitting component. The curing process includes curing for a third time at a first curing temperature and curing for a fourth time at a second curing temperature, wherein the second curing temperature is higher than the first curing temperature.

2. The method as described in claim 1, characterized in that, The conditions for centrifugation include at least one of the following: The centrifugation temperature is 40–50 °C; The first rotational speed is 750-850 rpm, and the first duration is 25-35 s; The second rotational speed is 2800–3200 rpm, and the second duration is 90–150 s; Angular acceleration is 0.8–1.2 rad / s². 2 .

3. The method as described in claim 1, characterized in that, The conditions for the curing process include at least one of the following: The first curing temperature is 55–65 °C, and the third curing time is 20–30 min; The second curing temperature is 115–125 °C, and the fourth curing time is 55–65 min.

4. A light-emitting component, characterized in that, The light-emitting component is manufactured by the method described in any one of claims 1 to 3.

5. The light-emitting component as described in claim 1, characterized in that, The light-emitting component includes: LED chip; A light-emitting layer is disposed on the light-emitting side of the light-emitting chip, the light-emitting layer comprising an encapsulating colloid and a light-emitting material distributed in the encapsulating colloid along the light-emitting direction.

6. The light-emitting component as described in claim 5, characterized in that, The light-emitting layer satisfies at least one of the following: In the light-emitting layer, the particle size of the light-emitting material gradually decreases along the light-emitting direction; In the light-emitting layer, the filling rate of the light-emitting material gradually decreases along the light-emitting direction; The effective refractive index of the light-emitting layer gradually decreases along the light-emitting direction; The scattering ability of the light-emitting layer gradually increases along the light emission direction.

7. The light-emitting component as described in claim 6, characterized in that, The light-emitting layer satisfies at least one of the following: In the light-emitting layer, the D50 particle size of the light-emitting material on the side closer to the light-emitting chip is 20-28 μm, and the D50 particle size of the light-emitting material on the side farther from the light-emitting chip is 3-6 μm; In the light-emitting layer, the D50 particle size of the light-emitting material varies with a unit thickness of 0.4 to 0.8 μm / μm along the light-emitting direction; The thickness of the light-emitting layer is 80~120 μm, and the thickness of the continuously gradually changing region of the filling rate of the light-emitting material accounts for more than 75% of the thickness of the light-emitting layer; In the light-emitting layer, the filling rate of the light-emitting material on the side closer to the light-emitting chip is 35%–45%, and the filling rate of the light-emitting material on the side farther from the light-emitting chip is 5%–15%. The equivalent refractive index of the light-emitting layer varies by ≤0.002 per micrometer along the light-emitting direction; The scattering coefficient of the light-emitting layer on the side away from the light-emitting chip is 3.2 to 4.5 times that of the light-emitting layer on the side closer to the light-emitting chip; In the light-emitting layer, the thermal quenching temperature of the light-emitting material on the side closest to the light-emitting chip is ≥190℃.

8. The light-emitting component as described in claim 5, characterized in that, The luminescent materials include: YAG phosphor, chlorosilicate phosphor, TAG phosphor, Ca-α-SiAlON phosphor, and β-Ca2SiO4:Eu. 2+ Phosphor, BaSi2O2N2:Eu 2+ At least one of phosphor, β-SiAlON phosphor, KSF phosphor, CASN phosphor, and red quantum dot.

9. A backlight module, characterized in that, The backlight module includes a light-emitting component manufactured by the method described in any one of claims 1 to 3, or a light-emitting component as described in any one of claims 4 to 8.

10. A display device, characterized in that, The display device includes a light-emitting component manufactured by the method of any one of claims 1 to 3, or a light-emitting component as described in any one of claims 4 to 8, or a backlight module as described in claim 9.

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