LED packaging method and packaging module

Abstract

The invention discloses an LED packaging method. The LED packaging method comprises the following steps: preparing a packaging bracket bonded with an LED chip, wherein a body of the packaging bracket is provided with a recess for accommodating the LED chip; preparing a liquid transfer system, and using the liquid transfer system to transfer the first liquid polymer into the recess of the packaging support; transferring the second liquid polymer to a surface center position of the first liquid polymer by using a liquid transfer system; regulating and controlling the second liquid polymer to be located at the surface center position of the first liquid polymer by adopting a heat-assisted oscillation alignment process or an inertia-assisted alignment process; and curing the first liquid polymer to form a large-angle free-form surface primary optical lens, and removing the second liquid polymer to complete the preparation of the LED packaging module. The technical scheme provided by the invention has the advantages of simplicity, flexibility, stable morphology parameters, producibility and low cost.

Description

Technical Field

[0001] The present invention relates to the field of light emitting diodes, and in particular to an LED packaging method and a packaging module. Background Art

[0002] In the LED industry chain, the packaging link connects upstream chips with downstream applications, providing mechanical protection, electrical signal connection, optical parameter control, and heat dissipation. Conventional LED packaging modules offer Lambertian light distribution, which cannot meet the demand for uniform illumination at close range. In the LED packaging process, lens manufacturing is the primary method for controlling light distribution. Lenses of different shapes can achieve diverse light distribution, such as conical lenses for narrow-angle light distribution and asymmetric lenses for asymmetric light distribution.

[0003] In order to achieve uniform illumination at close range and large angle, a secondary optical lens can be introduced into the LED package module. However, the air gap between the secondary optical lens and the primary optical lens will cause Fresnel loss when the light emitted from the LED chip passes through the primary lens-air-secondary lens, reducing the secondary light extraction efficiency. Figure 1 (a). And the secondary lens is large, which will increase the overall size of the device. Therefore, Figure 1 As shown in (b), the LED secondary and primary optical lenses are integrated, and the free-form primary optical lens is used to directly encapsulate the LED chip, which simplifies the optical system structure and reduces light loss, which is of great significance for realizing LED packaging modules with large-angle light distribution.

[0004] In recent years, free-form lens technology has rapidly developed, making its design and manufacturing more flexible. By designing free-form lenses, it is possible to reduce the intensity of narrow-angle light from LED chips, enabling the use of large-angle free-form lens-based single-stage optical lenses to control wide-angle light distribution in LED packaging modules. Currently, the main manufacturing processes for large-angle free-form lens-based single-stage optical lenses to control wide-angle light distribution in LED packaging modules are mold-based and mold-free methods.

[0005] A typical mold-based process is the top-mold process. This process places a ceramic substrate or plastic package bracket, complete with die bonding and wire bonding, on the lower mold of a top-mold machine. The mold is closed, vacuumed, and then the encapsulation colloid is injected and cured to produce the finished product. The top-mold process offers high manufacturing precision and efficiency, making it widely used. However, it relies on high-quality molds, resulting in a long development and manufacturing cycle, high costs and ongoing maintenance, and limited process flexibility, leading to high R&D and production costs.

[0006] The mold-free method also has problems. For example, the doctoral dissertation of Huazhong University of Science and Technology, "Electric Field Controlled Polymer Molding Technology and Its LED Packaging Application", discloses a mold-free preparation process based on droplet imprinting and electric field action. The encapsulation colloid is spot-coated on the surface of the substrate after solidification and wire bonding. The immiscible droplets with suitable interfacial tension and evaporable properties are transferred to the surface of the encapsulation colloid. The position of the droplets is controlled by the electric field. After stabilization, the encapsulation colloid is heated to solidify, and the droplets evaporate to obtain the finished product. This process does not require expensive molds and equipment, and is low in cost. By controlling the droplet-encapsulation colloid interfacial tension and droplet volume, free-form surface lenses with crater morphologies of different morphologies can be obtained, and the process flexibility is good. However, the encapsulation colloid takes tens of minutes to fix its morphology during the heating and curing process. During this period, the volume of the evaporable droplets changes continuously, resulting in continuous changes in the morphology of the encapsulation colloid and unstable lens morphology parameters. Moreover, the droplet alignment technology based on electric field action has extremely high requirements on the flatness of the packaging bracket, the placement position and the smoothness of the flat electrode, the parallel relationship and distance between the electrodes. The small errors that are difficult to avoid in mass production will cause inconsistent droplet alignment between different LED packaging modules, resulting in inconsistent lens morphology parameters. Summary of the Invention

[0007] The technical solution of the present application provides an LED packaging method and a packaging module, which realizes the preparation of a finished LED packaging module with a large-angle free-form surface with stable morphological parameters and a single optical lens to adjust the large-angle light distribution.

[0008] In a first aspect, the present application provides an LED packaging method, comprising the following steps: A. Prepare a package bracket bonded with an LED chip, wherein the package bracket body is provided with a recess for accommodating the LED chip; B. preparing a liquid transfer system, and using the liquid transfer system to transfer a first liquid polymer into the recess of the packaging bracket, wherein the first liquid polymer is a heat-curable polymer; C. Using a liquid transfer system, transferring a second liquid polymer to a center position on a surface of the first liquid polymer, wherein the second liquid polymer is a liquid material that is incompatible with the first liquid polymer, is non-volatile, and cannot be heated to evaporate or solidify; D. Using a thermally assisted oscillation alignment process or an inertia-assisted alignment process to control the second liquid polymer to be located at the center of the surface of the first liquid polymer; E. Use a gradient temperature curing process to cure the first liquid polymer to form a large-angle free-form surface primary optical lens, remove the second liquid polymer, and complete the preparation of the LED packaging module.

[0009] The LED packaging method provided in this application realizes the preparation of a finished LED packaging module with a large-angle free-form surface with stable morphology parameters and a single optical lens to control the large-angle light distribution. The technical principle is as follows: In the LED packaging method provided in the present application, a liquid transfer system is used to transfer a first liquid polymer that can be heat-cured into a recess of a packaging bracket bonded with an LED chip, covering the LED chip. Under the action of surface tension, the first liquid polymer becomes hemispherical after morphology is stabilized; a second liquid polymer that is insoluble in, non-volatile, and cannot be heated to evaporate and solidify with the first liquid polymer is transferred to the center position of the surface of the first liquid polymer using a liquid transfer system. Under the interaction of the surface tension of the first liquid polymer and the second liquid polymer, the morphology of the first liquid polymer is regulated; a heat-assisted oscillation alignment process or an inertia-assisted alignment process is used to ensure that the second liquid polymer is located at the center position of the surface of the first liquid polymer; a gradient temperature curing process is used to cure the first liquid polymer, and after removing the second liquid polymer, a large-angle free-form surface with stable morphology parameters and a one-time optical lens to regulate the large-angle light distribution LED packaging module finished product is obtained.

[0010] Optionally, a boss is provided on the top of the packaging bracket body surrounding the recess, and a transition surface is formed between the top outer edge of the boss and the bottom outer edge of the boss. A transition angle α is formed between the top surface of the boss and the transition surface, and 90°≤α≤105°. The boss structure can increase the volume of liquid polymer that the packaging bracket can bear, thereby preventing the liquid polymer from collapsing during the transfer and curing process.

[0011] Optionally, the liquid transfer system includes a motion device and a liquid discharge device; the motion direction, speed and distance of the motion device are accurately adjustable; the liquid discharge device includes a single liquid discharge head or an array of multiple liquid discharge heads that can release liquid in a quantitative manner, and the motion device controls the movement of the liquid discharge device.

[0012] Optionally, in step C, the central axis of the liquid outlet head of the liquid transfer system coincides with the central axis of the packaging bracket, and the height of the bottom end of the liquid outlet head from the highest point of the surface of the first liquid polymer is H, H ≥ 0.1 mm; the first liquid polymer is a heat-curable high thixotropic polymer, which avoids collapse from the top of the packaging bracket during transfer and heat curing, and the volume of the first liquid polymer is V1, and 2μL≤V1≤40μL; the volume of the second liquid polymer is V2, and 1μL≤V2≤20μL, V2≤0.5V1.

[0013] Optionally, the first liquid polymer is one of silicone, polyurethane, and epoxy resin; the second liquid polymer is one of silicone oil, isocyanate, and epoxy prepolymer.

[0014] Optionally, the thermally assisted oscillation alignment process in step D includes: D1. Prepare a heating device and a special structure fixture. Use the heating device to heat the special structure fixture to temperature T. Fix the package bracket to the special structure fixture. The angle between the mounting surface of the package plastic bracket on the special structure fixture and the horizontal plane is β = 180°. The material of the special structure fixture is a high specific heat capacity material. D2. Prepare an oscillation device and horizontally mount a specially constructed fixture on the oscillation device. Use an oscillation process to move the second liquid polymer to the center of the surface of the first liquid polymer, thereby achieving alignment of the second liquid polymer. The oscillation device can be an ultrasonic oscillator or a mechanical oscillator. During the oscillation process, the specially constructed fixture continuously provides heat to the first and second liquid polymers, increasing their fluidity and promoting alignment of the second liquid polymer.

[0015] Optionally, the inertial assisted alignment process in step D includes: after using a liquid transfer system to transfer the second liquid polymer to the center position of the surface of the first liquid polymer, setting the liquid transfer system to move along the central axis of the packaging bracket at a speed v in a direction away from the surface of the first liquid polymer, and the movement distance is L, where v ≥ 100 mm / s and L ≥ 1 mm.

[0016] Optionally, the process of curing the first liquid polymer in step E is a gradient temperature curing process, wherein the bottom end of the packaging bracket is at the highest temperature, and the temperature gradually decreases along the central axis of the packaging bracket toward the top end of the second liquid polymer.

[0017] Optionally, the light-emitting surface of the large-angle free-form surface primary optical lens described in step E consists of a first light-emitting surface and a second light-emitting surface, the first light-emitting surface is a free-form surface located at the top of the large-angle free-form surface primary optical lens and with a concave, flat or convex center, and the second light-emitting surface is a smooth surface located on the side wall of the large-angle free-form surface primary optical lens; wherein, when the first light-emitting surface is a free-form surface with a convex center, the central curvature of the first light-emitting surface is less than or equal to 2 / d, and d is the distance between the two farthest points on the outer edge of the bottom of the packaging bracket.

[0018] In a second aspect, the present application provides an LED packaging module, which is prepared by the above-mentioned LED packaging method.

[0019] Compared with the prior art, the technical solution of the present invention has the following characteristics: a second liquid polymer that is incompatible with the first liquid polymer, non-volatile, and cannot be heated to evaporate and solidify is used to ensure that the volume of the second liquid polymer does not change during the solidification process; a simple and reliable heat-assisted oscillation alignment process or an inertia-assisted alignment process is used to achieve consistency in the alignment effect during mass production; and a gradient temperature curing process is used to ensure high yield and producibility in the preparation of large-angle free-form surface one-time optical lens-controlled large-angle light distribution LED packaging modules.

[0020] Furthermore, the use of a special boss structure for the package support and a high-thixotropic first and second liquid polymers further ensures high yield and manufacturability in the production of LED package modules with large-angle free-form surfaces and single-shot optical lens control for wide-angle light distribution. This technical solution offers the advantages of simplicity and flexibility, stable morphological parameters, manufacturability, and low cost. It addresses the difficulty of mass-producing finished LED package modules with large-angle free-form surfaces and single-shot optical lens control for wide-angle light distribution using existing technical solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 (a) Schematic diagram of the light emission principle of the finished product of LED secondary optical lens structure package; Figure 1 (b) Schematic diagram of the light emission principle of the finished product of LED large-angle free-form surface one-time optical lens structure packaging.

[0022] Figure 2 This is a schematic diagram of the principle that the second liquid polymer wetting the inner and outer walls of the liquid discharge head during the release process of the liquid discharge device, and the second liquid polymer of indefinite volume is randomly adsorbed at different positions on the inner and outer walls of the liquid discharge head.

[0023] Figure 3 (a) is a schematic diagram of the LED packaging method according to Example 1 of the present invention after step A is completed; Figure 3 (b) is a bottom view of the package bracket of Example 1.

[0024] Figure 4 This is a schematic diagram of the principle of the special structural boss on the top of the packaging bracket body in the LED packaging method of the present invention producing a stagnation effect on the first liquid polymer.

[0025] Figure 5 This is a schematic diagram of the LED packaging method according to Example 1 of the present invention after step B is completed.

[0026] Figure 6 This is a schematic diagram of the LED packaging method according to Example 1 of the present invention after step C is completed.

[0027] Figure 7 This is a schematic diagram of the LED packaging method according to Example 1 of the present invention after step D is completed.

[0028] Figure 8 This is a schematic diagram of horizontally mounting the packaging bracket on a gradient heating device for curing in step E of the LED packaging method according to embodiment 1 of the present invention.

[0029] Figure 9 This is a schematic diagram of the finished product of the large-angle free-form surface single-stage optical lens-controlled large-angle light distribution LED packaging module ultimately achieved by the LED packaging method of Example 1 of the present invention.

[0030] Figure 10 (a) A finished product of a large-angle free-form surface LED packaging module with a primary optical lens for controlling large-angle light distribution, manufactured using the LED packaging method of Example 1 of the present invention; Figure 10 (b) is a schematic diagram showing the light pattern test results of a finished product of a large-angle free-form surface primary optical lens-controlled large-angle light distribution LED packaging module manufactured using the LED packaging method of Example 1 of the present invention; Figure 10 (c) is a schematic diagram of the finished product of the large-angle free-form surface single-stage optical lens-controlled large-angle light distribution LED packaging module mass-produced using the LED packaging method of Example 1 of the present invention.

[0031] Figure 11 (a) is a schematic diagram of the LED packaging method according to Example 2 of the present invention after step A is completed; Figure 11 (b) is a bottom view of the encapsulated plastic bracket of Example 2.

[0032] Figure 12 This is a schematic diagram of the LED packaging method according to embodiment 2 of the present invention after step B is completed.

[0033] Figure 13 This is a schematic diagram of the LED packaging method according to embodiment 2 of the present invention after step C is completed.

[0034] Figure 14 This is a schematic diagram of the LED packaging method according to embodiment 2 of the present invention after step D is completed.

[0035] Figure 15 This is a schematic diagram of horizontally mounting the packaging plastic bracket on a gradient heating device for curing in step E of the LED packaging method according to embodiment 2 of the present invention.

[0036] Figure 16 This is a schematic diagram of the finished product of the large-angle free-form surface single-stage optical lens-controlled large-angle light distribution LED packaging module ultimately achieved by the LED packaging method of Example 2 of the present invention.

[0037] Figure 17 This is a schematic diagram of the arrangement position of the chip in the recess of the packaging plastic bracket in the LED packaging method of Example 2 of the present invention.

[0038] Figure 18 (a) is a schematic diagram of the LED packaging method according to Example 3 of the present invention after step A is completed; Figure 18 (b) is a bottom view of the encapsulated plastic bracket of Example 3.

[0039] Figure 19 This is a schematic diagram of the LED packaging method according to Example 3 of the present invention after step B is completed.

[0040] Figure 20 This is a schematic diagram of the LED packaging method according to Example 3 of the present invention after step C is completed.

[0041] Figure 21 This is a schematic diagram of the LED packaging method according to Example 3 of the present invention after step D is completed.

[0042] Figure 22 This is a schematic diagram of horizontally mounting the packaging plastic bracket on a gradient heating device for curing in step E of the LED packaging method of embodiment 3 of the present invention.

[0043] Figure 23 This is a schematic diagram of the finished product of the large-angle free-form surface single-stage optical lens-controlled large-angle light distribution LED packaging module ultimately achieved by the LED packaging method of Example 3 of the present invention.

[0044] Figure 24 (a) A finished product of a large-angle free-form surface LED packaging module with a primary optical lens for controlling large-angle light distribution, manufactured using the LED packaging method of Example 3 of the present invention; Figure 24 (b) is a schematic diagram showing the light pattern test results of a finished product of a large-angle free-form surface primary optical lens-controlled large-angle light distribution LED packaging module manufactured using the LED packaging method of Example 3 of the present invention; Figure 24 (c) is a schematic diagram of the finished product of the large-angle free-form surface single-stage optical lens-controlled large-angle light distribution LED packaging module mass-produced using the LED packaging method of Example 3 of the present invention.

[0045] Figure 25 Schematic diagram of the arrangement position of the packaging plastic bracket in the LED packaging method of Example 3 of the present invention.

[0046] Figure 26 Schematic diagram of the arrangement position of the liquid outlet device in the LED packaging method of Example 3 of the present invention.

[0047] Figure 27 This is a schematic diagram of the finished product of the large-angle free-form surface primary optical lens-controlled large-angle light distribution LED packaging module ultimately achieved by the LED packaging method of Example 4 of the present invention.

[0048] Figure 28 This is a schematic diagram of the finished product of the large-angle free-form surface single-stage optical lens-controlled large-angle light distribution LED packaging module ultimately achieved by the LED packaging method of Example 5 of the present invention.

[0049] Figure 29 This is a schematic diagram of the finished product of the large-angle free-form surface one-time optical lens-controlled large-angle light distribution LED packaging module ultimately achieved by the LED packaging method of Example 6 of the present invention.

[0050] Figure 30This is a comparison chart of the simulation results of the light intensity distribution of the large-angle free-form surface one-time optical lens controlled large-angle light distribution LED packaging module and the ball-cap lens LED packaging module finally achieved in Examples 4, 5 and 6 of the present invention.

[0051] Figure 31 This is a schematic diagram of a finished product of a large-angle free-form surface primary optical lens-controlled large-angle light distribution LED packaging module ultimately achieved by the LED packaging method of Example 7 of the present invention.

[0052] Figure 32 This is a schematic diagram of a finished product of a large-angle free-form surface primary optical lens-controlled large-angle light distribution LED packaging module ultimately achieved by the LED packaging method of Example 8 of the present invention.

[0053] Figure 33 This is a schematic diagram of a finished product of a large-angle free-form surface primary optical lens-controlled large-angle light distribution LED packaging module ultimately achieved by the LED packaging method of Example 9 of the present invention.

[0054] Figure 34 This is a comparison chart of the simulation results of the light intensity distribution of the large-angle free-form surface primary optical lens regulating the large-angle light distribution LED packaging module and the ball-cap lens LED packaging module finally realized in Examples 7, 8 and 9 of the present invention. DETAILED DESCRIPTION

[0055] The terms used in the implementation section of this application are only used to explain the specific embodiments of this application and are not intended to limit this application.

[0056] Before describing the embodiments of the present application, the related technologies are first described.

[0057] The special structure fixture refers to a fixture that can be installed and fixed on an oscillating device, on the surface of which a packaging bracket can be installed and fixed, and the installation angle on the oscillating device and the angle between the surface on which the packaging bracket is installed and fixed and the horizontal plane are flexibly adjustable.

[0058] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0059] The present invention provides an LED packaging method, which realizes the preparation of a finished LED packaging module with a large-angle free-form surface and stable morphology parameters, and a single optical lens that controls the large-angle light distribution, including the following steps: A. Prepare a package bracket bonded with an LED chip, wherein the package bracket body is provided with a recess for accommodating the LED chip; B. preparing a liquid transfer system, and using the liquid transfer system to transfer a first liquid polymer into the recess of the packaging bracket, wherein the first liquid polymer is a heat-curable polymer; C. Using a liquid transfer system, transferring a second liquid polymer to a center position on a surface of the first liquid polymer, wherein the second liquid polymer is a liquid material that is incompatible with the first liquid polymer, is non-volatile, and cannot be heated to evaporate or solidify; D. Using a thermally assisted oscillation alignment process or an inertia-assisted alignment process to control the second liquid polymer to be located at the center of the surface of the first liquid polymer; E. Use a gradient temperature curing process to cure the first liquid polymer to form a large-angle free-form surface primary optical lens, remove the second liquid polymer, and complete the preparation of the LED packaging module.

[0060] In some embodiments, a method for preparing a package support bonded with an LED chip includes bonding the LED chip to a die-bonding position of the package support via a die-bonding layer, thereby mechanically securing the LED chip to the package support, establishing an electrical connection between the bottom electrode of the LED chip and the package support, and establishing a heat dissipation path for the LED chip; and connecting the surface electrode of the LED chip to the circuit of the package support via leads, thereby electrically connecting the top electrode of the LED chip to the package support. Multiple LED chips may be arranged in a circular or polygonal pattern. The leads are selected from the group consisting of gold, aluminum, copper, and silver wires.

[0061] In some embodiments, a boss is provided on the top of the package support body surrounding the recess, and a transition surface is formed between the top outer edge of the boss and the bottom outer edge of the boss. A transition angle α is formed between the top surface of the boss and the transition surface, and 90°≤α≤105°. The boss can increase the volume of the package support that can carry the liquid polymer. In addition, the range of the transition angle α is explained in principle, as shown in FIG. Figure 4 As shown, when the liquid polymer flows to the top outer edge of the boss, the angle formed between the tangent line of the liquid polymer profile at the top outer edge of the boss and the top surface of the boss is the stagnation angle θ. According to the principles of fluid mechanics, the minimum stagnation angle of the liquid polymer is θ min =θ0, the maximum stagnation angle of liquid polymer is θ max ={θ min +(180°-α,180°)} min , where θ0 is the contact angle of the liquid polymer on the top surface of the boss. The contact angle range of the liquid polymer and the surface of the packaging plastic bracket involved in the present invention is 15°≤θ0≤25°. In order to increase the volume of the packaging plastic bracket that can carry the liquid polymer as much as possible, θ max≥90°, according to the above formula, α≤105° is obtained. Due to the limitation of the manufacturing process of the packaging plastic bracket, the transition angle is 90°≤α≤105°.

[0062] In some embodiments, the encapsulation bracket is a plastic bracket made from a combination of EMC or PCT engineering plastics and copper or brass. The EMC or PCT engineering plastics are processed and molded onto a copper or brass substrate. Insulating strips are fabricated to isolate the positive and negative electrodes of the copper or brass substrate. A recessed structure is formed between the bracket structure and the copper or brass substrate to provide mechanical protection for the LED chip and limit the morphology of the liquid polymer after transfer.

[0063] In some embodiments, the liquid transfer system includes a motion device and a liquid discharge device; the motion direction, speed and distance of the motion device are accurately adjustable; the liquid discharge device includes a single liquid discharge head or an array of multiple liquid discharge heads that can quantitatively release liquid, and the motion device controls the precise movement of the liquid discharge device to ensure a one-time alignment effect of the central axis of the liquid discharge head and the central axis of the packaging bracket during the transfer of the second liquid polymer.

[0064] In some embodiments, the central axis of the liquid outlet head of the liquid transfer system in step C coincides with the central axis of the packaging support, and the height of the bottom of the liquid outlet head from the highest point of the surface of the first liquid polymer is H, H ≥ 0.1 mm; the first liquid polymer is a heat-curable high thixotropic polymer, the volume of the first liquid polymer is V1, and 2μL ≤ V1 ≤ 40μL; the second liquid polymer is a liquid material that is incompatible with the first liquid polymer, non-volatile, and cannot be heated to evaporate and solidify, the volume of the second liquid polymer is V2, and 1μL ≤ V2 ≤ 20μL, V2 ≤ 0.5V1. By regulating the volume and height H of the second liquid polymer and changing the materials of the first and second liquid polymers to regulate the interfacial tension between the two, the morphology of the first liquid polymer is controlled, thereby controlling the morphology of the final large-angle free-form surface primary optical lens. It should also be noted that the first liquid polymer is a heat-curable high thixotropic polymer to prevent the first liquid polymer from collapsing from the top of the packaging support during the transfer and curing process. Examples of the second liquid polymer include higher alcohols (such as undecanol, dodecanol, etc.), polyols (such as ethylene glycol, glycerol, etc.), liquid rubbers (such as liquid EPDM, styrene-butadiene rubber, etc.) and other liquids (such as liquid paraffin, edible oil, etc.).

[0065] In some embodiments, the first liquid polymer is one of silicone, polyurethane, and epoxy resin commonly used in the manufacture of LED packaging lenses; the second liquid polymer is one of silicone oil, isocyanate, and epoxy prepolymer. Although the second liquid polymer only needs to be incompatible with the first liquid polymer, non-volatile, and non-evaporable and non-curable by heating in order to control the morphology of the final optical lens of a specific shape, the hydrophilic hydroxyl groups contained in some of the liquid material's molecular chains will form hydrogen bonds with some groups in the first liquid polymer's molecular chains, causing the liquid material molecules at the first liquid polymer-liquid material interface to penetrate into the first liquid polymer's molecular chains, resulting in swelling of the first liquid polymer at the interface, thereby affecting the surface finish of the final lens (for example, dodecanol molecules penetrate into the silicone rubber molecular chains, causing the silicone rubber at the interface to swell, resulting in a white and rough surface on the corresponding lens). Due to the significant difference in molecular structure, the thermal expansion coefficient of the other type of liquid material and the first liquid polymer also differ significantly, resulting in large thermal strain at the first liquid polymer-liquid material interface during the heating and curing process, thereby causing wrinkles on the final lens surface (for example, the butadiene and styrene portions of the styrene-butadiene rubber molecular chains are prone to stretching and movement at high temperatures, resulting in large thermal strain at the styrene-butadiene rubber-silicone interface during the heating and curing process, resulting in irregular wrinkles on the corresponding lens surface). Therefore, the second liquid polymer material needs to be a liquid material whose molecular chain groups are not easy to form hydrogen bonds with the first liquid polymer molecular chain and whose molecular structure is slightly different from that of the first liquid polymer, such as silicone oil, isocyanate, and epoxy prepolymer.

[0066] In some embodiments, nanoparticles are uniformly dispersed within the first liquid polymer and / or the second liquid polymer, and the refractive index of the nanoparticles is the same as that of the polymer itself. Uniformly dispersing the nanoparticles within the first liquid polymer can further enhance the thixotropic properties of the first liquid polymer. Maintaining the same refractive index is intended to prevent light scattering caused by the nanoparticles within the large-angle free-form surface primary optical lens after curing, thereby affecting the light distribution control effect.

[0067] In some embodiments, the thermally assisted oscillation alignment process in step D includes: D1. Prepare a heating device and a special structure fixture. Use the heating device to heat the special structure fixture to temperature T. Fix the package bracket to the special structure fixture. The angle between the mounting surface of the package plastic bracket on the special structure fixture and the horizontal plane is β = 180°. The material of the special structure fixture is a high specific heat capacity material. D2. Prepare an oscillation device and horizontally mount the specially structured fixture on the oscillation device. Use an oscillation process to move the second liquid polymer to the center of the surface of the first liquid polymer, thereby achieving alignment of the second liquid polymer. The oscillation device can be an ultrasonic oscillator or a mechanical oscillator. During the oscillation process, the movement of the second liquid polymer is controlled by gravity by controlling the mounting position of the package bracket on the specially structured fixture and the mounting position of the specially structured fixture on the oscillation device. A heating device continuously provides heat to the first and second liquid polymers through the specially structured fixture, thereby increasing the fluidity of the first and second liquid polymers and achieving alignment of the second liquid polymer.

[0068] In some embodiments, the inertial assisted alignment process in step D includes: after using a liquid transfer system to transfer the second liquid polymer to the center position of the surface of the first liquid polymer, setting the liquid transfer system to move at a speed v along the central axis of the packaging bracket in a direction away from the surface of the first liquid polymer, and the movement distance is L, wherein v ≥ 100 mm / s, L ≥ 1 mm. During the transfer of the second liquid polymer, during the release process of the liquid transfer system, the second liquid polymer will have a wetting effect on the inner and outer wall surfaces of the liquid outlet head of the liquid transfer system, so that the indefinite volume of the second liquid polymer is randomly adsorbed at different positions on the inner and outer wall surfaces of the liquid outlet head, resulting in the final released second liquid polymer deviating from the center position of the surface of the first liquid polymer, such as Figure 2 As shown. Due to the surface tension and viscosity of the second liquid polymer, the discharge head remains in contact with a portion of the second liquid polymer even after the second liquid polymer is released. The liquid transfer system moves a distance L away from the surface of the first liquid polymer at a speed v, utilizing the inertia of the second liquid polymer to achieve alignment. The speed v has a minimum limit to ensure sufficient inertia for the second liquid polymer, and the movement distance L has a minimum limit to ensure sufficient duration for the inertial effect.

[0069] In some embodiments, the process for curing the first liquid polymer in step E is a gradient temperature curing process, wherein the temperature is highest at the bottom of the package support and gradually decreases along the central axis of the package support toward the top of the second liquid polymer. As the temperature gradient changes, the fluidity of the first and second liquid polymers changes from better to worse, and the curing rate of the first liquid polymer changes from faster to slower. This gradient in fluidity and curing rate effectively prevents collapse of the first and second liquid polymers during the heat curing process, thereby ensuring a high yield.

[0070] In some embodiments, the light-emitting surface of the large-angle free-form surface primary optical lens described in step E consists of a first light-emitting surface and a second light-emitting surface, the first light-emitting surface is a free-form surface located at the top of the large-angle free-form surface primary optical lens and with a concave, flat or convex center, and the second light-emitting surface is a smooth curved surface located on the side wall of the large-angle free-form surface primary optical lens; wherein, when the first light-emitting surface is a free-form surface with a convex center, the central curvature of the first light-emitting surface is less than or equal to 2 / d, d is the distance between the two farthest points on the outer edge of the bottom of the packaging bracket, and the central curvature of the first light-emitting surface is limited to be less than or equal to the surface curvature of the spherical cap structure with the circumscribed circle of the bottom of the packaging bracket as the bottom surface, thereby ensuring the refraction and total reflection effects of the light emitted by the LED at the first light-emitting surface. When the small-angle light emitted by the LED chip reaches the first light-emitting surface, it is converted into large-angle light due to refraction and total reflection; the second light-emitting surface is a smooth curved surface located on the side wall of the large-angle free-form surface primary optical lens, and the large-angle light is emitted from the second light-emitting surface, thereby realizing an LED packaging module in which the large-angle free-form surface primary optical lens can regulate large-angle light distribution.

[0071] The embodiment of the present application further provides an LED packaging module, which is prepared by the above-mentioned LED packaging method. Example 1

[0072] like Figure 3-10 As shown, a LED packaging method includes the following steps: A: If Figure 3-4 As shown, a plastic package bracket 101 and an LED chip 102 are prepared. The material of the plastic package bracket 101 is a combination of EMC (Epoxy Molding Compound) and red copper. The distance between the two farthest points on the bottom outer edge of the plastic package bracket 101 is d, where d = 4.24 mm. The body of the plastic package bracket 101 is provided with a recess for accommodating the LED chip 102. The top of the body is provided with a boss surrounding the recess. The top outer edge of the boss forms a transition surface with the bottom outer edge of the boss. The top surface of the boss and the transition surface form a transition angle α, where α = 100°. LED chip 102 is a high-efficiency vertical yellow LED chip with a dominant wavelength of 560nm. Using a die-bonding process, LED chip 102 is bonded to the die-bonding position of the plastic package bracket 101 through a die-bonding layer 103. Using a wire bonding process, the surface electrodes of the LED chip 102 are connected to the circuit of the plastic package bracket 101 via wires 104 to achieve electrical connection.

[0073] B: Prepare a liquid transfer system 111, including a motion device 1111 and a liquid discharge device 1112, wherein the liquid discharge device 1112 includes a liquid discharge head 11121; prepare a first liquid polymer 121, which is silicone, add the first liquid polymer 121 into the liquid discharge device 1112, control the liquid discharge device 1112 to move above the depression of the encapsulated plastic bracket 101 through the motion device 1111, and use the liquid discharge device 1112 to transfer V1 volume of the first liquid polymer 121 to the depression of the encapsulated plastic bracket 101, where V1 = 4 μL.

[0074] C: Prepare a second liquid polymer 122. The second liquid polymer 122 is a 12500 cs viscosity silicone oil uniformly doped with nanoparticles at a mass concentration of 1%. Generally, the surface tension of silicone oil increases with increasing viscosity. By using silicone oils of different viscosities, the interfacial tension between the first liquid polymer and the second liquid polymer can be regulated. The second liquid polymer 122 is added to the liquid discharge device 1112. The liquid discharge device 1112 is controlled by the motion device 1111 to move to the center position of the surface of the first liquid polymer 121 in the depression of the packaging plastic bracket 101, and the height between the bottom end of the liquid discharge head 11121 and the highest point of the surface of the first liquid polymer 121 is H, where H=0.5 mm. The second liquid polymer 122 with a volume of V2 is transferred to the center position of the surface of the first liquid polymer 121 by the liquid discharge device 1112, where V2=1.5 μL.

[0075] D: Prepare a special structure fixture 131, use a heating device to heat the special structure fixture 131 to a temperature T1, preferably, T1 = 120 ° C, install the encapsulated plastic bracket 101 on the special structure fixture 131, and the angle between the installation surface of the encapsulated plastic bracket 101 on the special structure fixture and the horizontal plane is β = 180 °; prepare a mechanical oscillator 132, install the special structure fixture 131 horizontally on the mechanical oscillator 132, and use an oscillation process to move the second liquid polymer 122 to the center position of the surface of the first liquid polymer 121.

[0076] E: Prepare a gradient temperature heating device 141, and horizontally install the packaging plastic bracket 101 on the gradient temperature heating device 141. Preferably, use a heating temperature T2 = 120°C and a heating time t2 = 120 min to solidify the first liquid polymer 121; remove the second liquid polymer 122 on the surface of the first liquid polymer 121, and finally obtain a free-form surface lens, thereby realizing a large-angle free-form surface one-time optical lens to regulate a large-angle light distribution LED packaging module finished product 151.

[0077] like Figure 9As shown, an LED packaging structure includes a packaging plastic bracket 101, an LED chip 102, a solid crystal layer 103, a lead 104, and a large-angle free-form surface primary optical lens 105. An LED chip 102 is bonded to the solid crystal position of the packaging plastic bracket 101 through the solid crystal layer 103; the surface electrode of the LED chip 102 is connected to the circuit of the packaging plastic bracket 101 through the lead 104; the recess of the packaging plastic bracket 101 is filled with the large-angle free-form surface primary optical lens 105 to achieve sealed protection of the LED chip 102, and at the same time, the shape of the large-angle free-form surface primary optical lens 105 on the upper surface of the packaging plastic bracket 101 is a free-form surface, thereby realizing the large-angle free-form surface primary optical lens to regulate the large-angle light distribution LED packaging module finished product 151.

[0078] Among them, the light-emitting surface of the large-angle free-form surface primary optical lens 105 consists of a first light-emitting surface and a second light-emitting surface, wherein the first light-emitting surface is a free-form surface located at the top of the lens 105 and concave in the center, and the second light-emitting surface is a smooth curved surface located on the side wall of the lens 105, gradually transitioning from the first light-emitting surface to the upper surface of the top boss of the encapsulating plastic bracket.

[0079] like Figure 10 (a) shows a physical picture of a finished product 151 of a LED packaging module with a large-angle free-form surface and a primary optical lens 105 for regulating large-angle light distribution produced by the packaging method in Example 1; Figure 10 (b) shows the measured light distribution curve of the finished product 151 of the large-angle free-form surface primary optical lens 105 regulating the large-angle light distribution LED package module; Figure 10 (b) It can be seen that the average beam angle of the large-angle free-form surface primary optical lens 105 regulating the large-angle light distribution LED package module finished product 151 is 151°, which proves that it is feasible to use the packaging method in Example 1 to manufacture the large-angle free-form surface primary optical lens 105 regulating the large-angle light distribution LED package module finished product; Figure 10 (c) shows a finished product of a large-angle free-form surface primary optical lens 105 controlling large-angle light distribution LED packaging module produced in batches by the packaging method in Example 1; Figure 10 (c) It can be seen that the finished product of the large-angle free-form surface one-time optical lens 105 for regulating large-angle light distribution LED packaging module produced in batches using the packaging method in Example 1 has stable morphology parameters, which proves that it is feasible to use the packaging method in Example 1 to mass-produce the finished product of the large-angle free-form surface one-time optical lens for regulating large-angle light distribution LED packaging module. Example 2

[0080] like Figure 11-17 As shown, a LED packaging method includes the following steps: A: If Figure 11 As shown, a plastic package bracket 201 is prepared, and four LED chips 202, 203, 204, and 205 are provided. The material of the plastic package bracket 201 is a combination of EMC (Epoxy Molding Compound) and brass. The distance between the two farthest points on the bottom outer edge of the plastic package bracket 201 is d, where d = 7.07 mm. The body of the plastic package bracket 201 is provided with a recess for accommodating the LED chips 202, 203, 204, and 205. The top of the body is provided with a boss arranged around the recess, and the top outer edge of the boss is aligned with the bottom outer edge of the boss. A transition surface is formed between the top surface of the boss and the transition surface, and a transition angle of α is formed between the top surface of the boss and the transition surface. In this embodiment, α=105°; the LED chip 202 is a high-efficiency vertical structure blue LED chip with a main wavelength of 460nm, the LED chip 203 is a high-efficiency vertical structure green LED chip with a main wavelength of 520nm, the LED chip 204 is a high-efficiency vertical structure yellow LED chip with a main wavelength of 560nm, and the LED chip 205 is a high-efficiency vertical structure red LED chip with a main wavelength of 620nm, and they are spaced apart in a square arrangement in the recess of the packaging plastic bracket 201, as shown in FIG. Figure 17 As shown; using a solid crystal process, the LED chips 202, 203, 204, 205 are bonded to the solid crystal position of the packaging plastic bracket 201 through the solid crystal layer 206; using a wire bonding process, the surface electrodes of the LED chips 202, 203, 204, 205 are connected to the circuit of the packaging plastic bracket 201 through the wire 207 to achieve electrical connection.

[0081] B: Prepare a liquid transfer system 211, including a motion device 2111 and a liquid discharge device 2112, wherein the liquid discharge device 2112 includes a liquid discharge head 21121; prepare a first liquid polymer 221, wherein the first liquid polymer 221 is an epoxy resin uniformly doped with nanoparticles at a mass concentration of 5%, add the first liquid polymer 221 into the liquid discharge device 2112, and control the liquid discharge device 2112 to move above the depression of the encapsulated plastic bracket 201 through the motion device 2111, and use the liquid discharge device 2112 to transfer a volume V1 of the first liquid polymer 221 into the depression of the encapsulated plastic bracket 201, wherein V1 = 10 μL.

[0082] C: Prepare the second liquid polymer 222. The second liquid polymer 122 is an epoxy prepolymer with a viscosity of 3000 cs. Generally, the surface tension of the epoxy prepolymer increases with the increase of viscosity. By using epoxy prepolymers of different viscosities, the interfacial tension between the first liquid polymer and the second liquid polymer can be controlled. The second liquid polymer 222 is added to the liquid discharge device 2112. The liquid discharge device 2112 is controlled by the motion device 2111 to move to the center position of the surface of the first liquid polymer 221 in the depression of the packaging plastic bracket 201, and the height between the bottom end of the liquid discharge head 21121 and the highest point of the surface of the first liquid polymer 221 is H, where H=2 mm. The second liquid polymer 222 with a volume of V2 is transferred to the center position of the surface of the first liquid polymer 221 by the liquid discharge device 2112, where V2=3 μL.

[0083] D: The motion device 2111 is set to control the liquid outlet device 2112 to move at a speed v along the central axis of the packaging plastic bracket 201 in a direction away from the surface of the first liquid polymer 221 by a distance L. Preferably, v=200mm / s, L=10mm.

[0084] E: Prepare a gradient temperature heating device 231, and horizontally install the packaging plastic bracket 201 on the gradient temperature heating device 231. Preferably, use a heating temperature T1 = 120°C and a heating time t1 = 120min to solidify the first liquid polymer 221; remove the second liquid polymer 222 on the surface of the first liquid polymer 221, and finally obtain a free-form surface lens, thereby realizing a large-angle free-form surface one-time optical lens to regulate a large-angle light distribution LED packaging module finished product 241.

[0085] like Figure 16 As shown, an LED packaging structure includes a packaging plastic bracket 201, four LED chips 202-205, a solid crystal layer 206, a lead 207, and a large-angle free-form surface primary optical lens 208. The four LED chips 202, 203, 204, and 205 are bonded to the solid crystal position of the packaging plastic bracket 201 through the solid crystal layer 206; the surface electrodes of the LED chips 202, 203, 204, and 205 are connected to the circuit of the packaging plastic bracket 201 through the lead 207; the large-angle free-form surface primary optical lens 208 is used to fill the recess of the packaging plastic bracket 201 to achieve sealed protection of the LED chips 202, 203, 204, and 205, and at the same time, the shape of the large-angle free-form surface primary optical lens 208 on the upper surface of the packaging plastic bracket 201 is a free-form surface, thereby achieving the large-angle free-form surface primary optical lens 208 to regulate the large-angle light distribution LED packaging module finished product 241.

[0086] Among them, the light-emitting surface of the large-angle free-form surface primary optical lens 208 is composed of a first light-emitting surface and a second light-emitting surface, wherein the first light-emitting surface is a free-form surface located at the top of the large-angle free-form surface primary optical lens 208 and with a flat center, and the second light-emitting surface is a smooth curved surface located on the side wall of the large-angle free-form surface primary optical lens 208, gradually transitioning from the first light-emitting surface to the upper surface of the top boss of the packaging plastic bracket.

[0087] Comparing Example 2 with Example 1, it is shown that by changing the materials of the first liquid polymer and the second liquid polymer, the interfacial tension between the first liquid polymer and the second liquid polymer can be regulated to achieve control of the morphology of the first liquid polymer, thereby achieving a large-angle free-form surface primary optical lens with a large morphological difference such as a concave center and a flat first light-emitting surface; uniformly dispersing a certain concentration of nanoparticles inside the first liquid polymer or the second liquid polymer can avoid the collapse of the first liquid polymer from the surface of the packaging bracket during the transfer and curing process; using a thermally assisted oscillation alignment process or an inertia-assisted alignment process can achieve the movement of the second liquid polymer on the surface of the first liquid polymer, and ultimately ensure that the second liquid polymer is located at the center of the surface of the first liquid polymer. Example 3

[0088] like Figure 18-26 As shown, a LED packaging method includes the following steps: A: If Figure 18 As shown, prepare to package plastic brackets 3001, 3002, 3003, 3004, LED chips 3005, 3006, 3007, 3008; the distance between the two farthest points on the outer edge of the bottom of the packaging plastic brackets 3001, 3002, 3003, 3004 is d, where d=5.66mm, as shown Figure 25As shown, the encapsulating plastic brackets 3001, 3002, 3003, and 3004 are located in the same plane and spaced apart in a square arrangement. The material thereof is a combination of PCT (Poly 1,4-cyclohexylenedimethyleneterephthalate) and brass. The bodies of the encapsulating plastic brackets 3001, 3002, 3003, and 3004 are respectively provided with recesses for accommodating LED chips 3005, 3006, 3007, and 3008. The top of the body is provided with a boss arranged around the recess. A transition surface is formed between the top outer edge of the boss and the bottom outer edge of the boss. A transition angle of α is formed between the top surface of the boss and the transition surface. In this embodiment, α= 90°; LED chips 3005, 3006, 3007, and 3008 are high-efficiency vertical-structured red LED chips with a main wavelength of 620nm; a die bonding process is used to bond LED chips 3005, 3006, 3007, and 3008 to the die bonding positions of packaging plastic supports 3001, 3002, 3003, and 3004 respectively through die bonding layers 3009, 3010, 3011, and 3012; a wire bonding process is used to connect surface electrodes of LED chips 3005, 3006, 3007, and 3008 to circuits of packaging plastic supports 3001, 3002, 3003, and 3004 respectively through wires 3013, 3014, 3015, and 3016 to achieve electrical connection.

[0089] B: Prepare a liquid transfer system 311, including a motion device 3111 and liquid outlet devices 3112, 3113, 3114, 3115, wherein the liquid outlet devices 3112, 3113, 3114, 3115 are located on the same plane and are spaced apart in a square arrangement, such as Figure 26 As shown, and respectively include liquid discharge heads 31121, 31131, 31141, and 31151; prepare a first liquid polymer 321, the first liquid polymer 321 is silicone, add the first liquid polymer 321 into the liquid discharge devices 3112, 3113, 3114, and 3115, and control the liquid discharge devices 3112, 3113, 3114, and 3115 to move above the depressions of the packaging plastic supports 3001, 3002, 3003, and 3004 respectively by the motion device 3111, and use the liquid discharge devices 3112, 3113, 3114, and 3115 to transfer V1 volume of the first liquid polymer 321 to the depressions of the packaging plastic supports 3001, 3002, 3003, and 3004 respectively, where V1=6μL.

[0090] C: Prepare a second liquid polymer 322, which is 50 cs viscosity silicone oil. Add the second liquid polymer 322 to the interior of the liquid discharge devices 3112, 3113, 3114, and 3115. Use the motion device 3111 to control the liquid discharge devices 3112, 3113, 3114, and 3115 to move to the center position of the surface of the first liquid polymer 321 in the depression of the packaging plastic bracket 3001, 3002, 3003, and 3004, respectively. The height between the bottom end of the liquid discharge head 31121, 31131, 31141, and 31151 and the highest point of the surface of the first liquid polymer 321 is H, where H = 1 mm. Use the liquid discharge devices 3112, 3113, 3114, and 3115 to transfer a volume of V2 of the second liquid polymer 322 to the center position of the surface of the first liquid polymer 321, where V2 = 1.5 μL.

[0091] D: Prepare a special structure fixture 331, use a heating device to heat the special structure fixture 331 to a temperature T1, preferably, T1 = 100 ° C, install the encapsulated plastic brackets 3001, 3002, 3003, 3004 on the special structure fixture 131, and the angle between the installation surface of the encapsulated plastic brackets 3001, 3002, 3003, 3004 on the special structure fixture and the horizontal plane is β = 180 °; prepare an ultrasonic oscillator 332, install the special structure fixture 331 horizontally on the ultrasonic oscillator 332, and use an oscillation process to move the second liquid polymer 322 to the center position of the surface of the first liquid polymer 321.

[0092] E: Prepare a gradient temperature heating device 341, and horizontally install the packaging plastic brackets 3001, 3002, 3003, and 3004 on the gradient temperature heating device 341. Preferably, use a heating temperature T2 = 120°C and a heating time t2 = 120 min to solidify the first liquid polymer 321; remove the second liquid polymer 322 on the surface of the first liquid polymer 321, and finally obtain a free-form surface lens, thereby realizing a large-angle free-form surface one-time optical lens to regulate a large-angle light distribution LED packaging module finished product 351, 352, 353, and 354.

[0093] like Figure 23As shown, taking one of the finished products 351 of the LED packaging module with large-angle free-form surface one-time optical lens regulating large-angle light distribution as an example, an LED packaging structure includes a packaging plastic bracket 3001, an LED chip 3005, a solid crystal layer 3009, a lead 3013, and a large-angle free-form surface one-time optical lens 3017. An LED chip 3005 is bonded to the solid crystal position of the packaging plastic bracket 3001 through the solid crystal layer 3009; the surface electrode of the LED chip 3005 is connected to the circuit of the packaging plastic bracket 3001 through the lead 3013; the recess of the packaging plastic bracket 3001 is filled with the large-angle free-form surface one-time optical lens 3017 to achieve sealed protection of the LED chip 3005, and at the same time, the shape of the portion of the lens 3017 on the upper surface of the packaging plastic bracket 3001 is a free-form surface, thereby realizing the finished product 351 of the LED packaging module with large-angle free-form surface one-time optical lens regulating large-angle light distribution.

[0094] Among them, the light-emitting surface of the large-angle free-form surface primary optical lens 3017 is composed of a first light-emitting surface and a second light-emitting surface, wherein the first light-emitting surface is a free-form surface located at the top of the large-angle free-form surface primary optical lens 3017 and convex at the center, and the second light-emitting surface is a smooth curved surface located on the side wall of the large-angle free-form surface primary optical lens 3017, gradually transitioning from the first light-emitting surface to the upper surface of the top boss of the packaging plastic bracket.

[0095] like Figure 24 (a) shows a physical picture of a finished product 351 of a large-angle free-form surface primary optical lens-controlled large-angle light distribution LED packaging module manufactured by the packaging method in Example 3; Figure 24 (b) shows the measured light distribution curve of the finished product 351 of the LED package module with large-angle free-form surface and single-stage optical lens for adjusting large-angle light distribution; Figure 24 (b) It can be seen that the average beam angle of the finished product 351 of the large-angle free-form surface optical lens-controlled large-angle light distribution LED packaging module is 140°, which proves that it is feasible to use the packaging method in Example 3 to manufacture the finished product of the large-angle free-form surface optical lens-controlled large-angle light distribution LED packaging module; Figure 24 (c) shows a finished product of a large-angle free-form surface primary optical lens-controlled large-angle light distribution LED packaging module produced in batches by the packaging method in Example 3; Figure 24 (c) It can be seen that the finished products of the large-angle free-form surface one-time optical lens-controlled large-angle light distribution LED packaging modules produced in batches using the packaging method in Example 3 have stable morphology parameters, which proves that it is feasible to use the packaging method in Example 3 to mass-produce the finished products of the large-angle free-form surface one-time optical lens-controlled large-angle light distribution LED packaging modules.

[0096] Comparing Example 3 with Example 1, it is shown that when silicone is selected as the first liquid polymer and silicone oil is selected as the second liquid polymer, the interfacial tension between the first liquid polymer and the second liquid polymer can be regulated by changing the viscosity of the silicone oil, thereby achieving control of the morphology of the first liquid polymer, and further achieving a large-angle free-form surface primary optical lens with large morphological differences such as the first light-emitting surface being concave or convex in the center; when the thixotropic values ​​of the first liquid polymer and the second liquid polymer are high enough, there is no need to evenly disperse nanoparticles inside the two, so that the first liquid polymer can be stable and not collapse on the surface of the packaging bracket during the transfer and curing process. Example 4

[0097] Example 4 is basically the same as Example 1, except that: The volume of the second liquid polymer transferred to the center of the surface of the first liquid polymer by the liquid outlet device is V2=1μL, and finally the large-angle free-form surface one-time optical lens regulating large-angle light distribution LED packaging module finished product 451 is realized, and its structural schematic diagram is shown as follows Figure 27 shown. Example 5

[0098] Example 5 is basically the same as Example 1, except that: The volume of the second liquid polymer transferred to the center of the surface of the first liquid polymer by the liquid outlet device is V2=0.5μL, and finally the large-angle free-form surface one-time optical lens regulating large-angle light distribution LED packaging module finished product 551 is realized, and its structural schematic diagram is shown as follows Figure 28 shown. Example 6

[0099] Example 6 is basically the same as Example 1, except that: The volume of the second liquid polymer transferred to the center of the surface of the first liquid polymer by the liquid outlet device is V2=1.8μL, and finally the large-angle free-form surface one-time optical lens regulating large-angle light distribution LED packaging module finished product 651 is realized. Its structural diagram is shown as follows Figure 29 shown.

[0100] By comparing Examples 4, 5, and 6, it can be seen that, under the condition that other conditions remain the same, by changing the volume of the second liquid polymer transferred to the center of the first liquid polymer surface, the morphology of the first liquid polymer can be changed, thereby achieving the morphology adjustment of the large-angle free-form surface primary optical lens with the center of the first light-emitting surface concave. Figure 30 As shown, the simulation results of the light intensity distribution show that if the volume of the second liquid polymer is too large or too small, it is not conducive to the light shape control effect of the final large-angle free-form surface optical lens. Example 7

[0101] Example 7 is basically the same as Example 3, except that: The volume of the second liquid polymer transferred to the center of the surface of the first liquid polymer by the liquid outlet device is V2=1μL, and finally the large-angle free-form surface one-time optical lens regulating large-angle light distribution LED packaging module finished products 751, 752, 753, 754 are realized. Taking one of the large-angle free-form surface one-time optical lens regulating large-angle light distribution LED packaging module finished products 751 as an example, its structural schematic diagram is shown as follows Figure 31 shown. Example 8

[0102] Example 8 is basically the same as Example 3, except that: The volume of the second liquid polymer transferred to the center of the surface of the first liquid polymer by the liquid outlet device is V2=2μL, and finally the large-angle free-form surface one-time optical lens regulating large-angle light distribution LED packaging module finished products 851, 852, 853, 854 are realized. Taking one of the large-angle free-form surface one-time optical lens regulating large-angle light distribution LED packaging module finished products 851 as an example, its structural schematic diagram is shown as follows Figure 32 shown. Example 9

[0103] Example 9 is basically the same as Example 3, except that: The volume of the second liquid polymer transferred to the center of the surface of the first liquid polymer by the liquid outlet device is V2=2.5μL, and finally the large-angle free-form surface one-time optical lens regulating large-angle light distribution LED packaging module finished products 951, 952, 953, and 954 are realized. Taking one of the large-angle free-form surface one-time optical lens regulating large-angle light distribution LED packaging module finished products 951 as an example, its structural schematic diagram is shown as follows Figure 33 shown.

[0104] Comparing Examples 7, 8, and 9, it can be seen that, under the condition that other conditions remain the same, by changing the volume of the second liquid polymer transferred to the center of the first liquid polymer surface, the morphology of the first liquid polymer can be changed, thereby achieving the morphology adjustment of the large-angle free-form surface primary optical lens with the center of the first light-emitting surface convex outward. Figure 34 As shown, the simulation results of the light intensity distribution show that with the increase of the volume of the second liquid polymer, the light shape control effect of the large-angle free-form surface optical lens is better.

[0105] The above embodiments are intended only to illustrate the design concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. The scope of protection of the present invention is not limited to the above embodiments. Therefore, any equivalent changes or modifications made based on the principles and design concepts disclosed in the present invention are within the scope of protection of the present invention.

Claims

1. A method for encapsulating an LED, characterized in that: The following steps are involved: A. Prepare a package bracket bonded with an LED chip, wherein the package bracket body is provided with a recess for accommodating the LED chip; B. preparing a liquid transfer system, and using the liquid transfer system to transfer a first liquid polymer into the recess of the packaging bracket, wherein the first liquid polymer is a heat-curable polymer; C. Using a liquid transfer system, transferring a second liquid polymer to a center position on a surface of the first liquid polymer, wherein the second liquid polymer is a liquid material that is incompatible with the first liquid polymer, is non-volatile, and cannot be heated to evaporate or solidify; D. Using a thermally assisted oscillation alignment process or an inertia-assisted alignment process to control the second liquid polymer to be located at the center of the surface of the first liquid polymer; E. Use a gradient temperature curing process to cure the first liquid polymer to form a large-angle free-form surface primary optical lens, remove the second liquid polymer, and complete the preparation of the LED packaging module.

2. The LED packaging method according to claim 1, wherein: A boss surrounding the recess is provided on the top of the package bracket body, a transition surface is formed between the top outer edge of the boss and the bottom outer edge of the boss, a transition angle α is formed between the top surface of the boss and the transition surface, and 90°≤α≤105°.

3. The LED packaging method according to claim 1, wherein: The liquid transfer system includes a motion device and a liquid discharge device; the motion direction, speed and distance of the motion device are accurately adjustable; the liquid discharge device includes a single liquid discharge head or an array of multiple liquid discharge heads that can release liquid in a quantitative manner, and the motion device controls the movement of the liquid discharge device.

4. The LED packaging method according to claim 1, wherein: In step C, the central axis of the liquid outlet head of the liquid transfer system coincides with the central axis of the packaging bracket, and the height of the bottom end of the liquid outlet head from the highest point of the surface of the first liquid polymer is H, H ≥ 0.1 mm; the first liquid polymer is a heat-curable high thixotropic polymer, the volume of the first liquid polymer is V1, and 2 μL ≤ V1 ≤ 40 μL; the volume of the second liquid polymer is V2, and 1 μL ≤ V2 ≤ 20 μL, V2 ≤ 0.5V1.

5. The LED packaging method according to claim 4, wherein: The first liquid polymer is one of silicone, polyurethane, and epoxy resin; the second liquid polymer is one of silicone oil, isocyanate, and epoxy prepolymer.

6. The LED packaging method according to claim 1, wherein: The thermally assisted oscillation alignment process in step D includes: D1. Prepare a heating device and a special structure fixture. Use the heating device to heat the special structure fixture to temperature T. Fix the package bracket to the special structure fixture. The angle between the mounting surface of the package plastic bracket on the special structure fixture and the horizontal plane is β = 180°. The material of the special structure fixture is a high specific heat capacity material. D2. Prepare an oscillation device, horizontally install a special structure fixture on the oscillation device, and use an oscillation process to move the second liquid polymer to the center position of the surface of the first liquid polymer to achieve alignment of the second liquid polymer; wherein the oscillation device is an ultrasonic oscillator or a mechanical oscillator.

7. The LED packaging method according to claim 1, wherein: The inertial assisted alignment process described in step D includes: using a liquid transfer system to transfer the second liquid polymer to the center position of the surface of the first liquid polymer, setting the liquid transfer system to move along the central axis of the packaging bracket at a speed v in a direction away from the surface of the first liquid polymer, and the movement distance is L, where v ≥ 100 mm / s and L ≥ 1 mm.

8. The LED packaging method according to claim 1, wherein: In the gradient temperature curing process in step E, the bottom end of the package support is at the highest temperature, and the temperature gradually decreases along the central axis of the package support toward the top end of the second liquid polymer.

9. The LED packaging method according to claim 1, wherein: The light-emitting surface of the large-angle free-form surface primary optical lens described in step E consists of a first light-emitting surface and a second light-emitting surface, the first light-emitting surface is a free-form surface located at the top of the large-angle free-form surface primary optical lens and with a concave, flat or convex center, and the second light-emitting surface is a smooth surface located on the side wall of the large-angle free-form surface primary optical lens; wherein, when the first light-emitting surface is a free-form surface with a convex center, the central curvature of the first light-emitting surface is less than or equal to 2 / d, and d is the distance between the two farthest points on the outer edge of the bottom of the packaging bracket.

10. An LED package module, characterized in that: Prepared according to the LED packaging method according to any one of claims 1-9.

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