Preparation method of packaged lamp bead and packaged lamp bead

Abstract

The invention relates to the technical field of LED packaging, in particular to a preparation method of a packaged lamp bead and the packaged lamp bead, the preparation method of the packaged lamp bead provided by the invention comprises the following steps: providing a flip chip structure comprising a substrate, an LED chip and a fluorescent glue layer which are arranged in sequence; a groove aligned with the LED chip is formed in the face, away from the LED chip, of the fluorescent glue layer in a glue dispensing or printing mode, a reflecting material is subjected to mold pressing in the groove to form a convex reflecting structure, the groove is filled with at least part of the convex reflecting structure, and a packaged lamp bead is formed; or, providing a prefabricated optical structure comprising a convex reflection structure prepared in a dispensing manner, and fixing the prefabricated optical structure on the surface, deviating from the LED chip, of the fluorescent glue layer in an alignment mold pressing or pressing manner to form a packaged lamp bead. The convex reflection structure is prevented from being manufactured by adopting a special mold, so that the manufacturing cost is lower, and more cost is saved.

Description

Technical Field

[0001] This invention relates to the field of LED packaging technology, and in particular to a method for preparing packaged LED beads and the packaged LED beads themselves. Background Art

[0002] In LED packaging technology, flip-chip is widely used due to its advantages such as high thermal conductivity and high power density. However, in white light solutions, its emission angle is often smaller than that of traditional conventional chips.

[0003] Existing POB white light solutions typically increase the emission angle by adding a reflective structure to the LED light-emitting structure. However, such reflective structures, especially non-planar reflective structures, usually require the use of special molds for fabrication, resulting in high manufacturing costs. Summary of the Invention

[0004] To address the problem of high manufacturing costs associated with the use of specially designed molds to create non-planar reflective structures that increase the light emission angle in existing technologies, this invention provides a method for preparing encapsulated LED beads and an encapsulated LED bead.

[0005] The present invention provides a method for preparing an encapsulated LED chip, comprising the following steps: providing a flip-chip structure; the flip-chip structure comprising a substrate, an LED chip, and a phosphor layer arranged sequentially; forming a groove aligned with the LED chip on the side of the phosphor layer opposite to the LED chip by dispensing or printing, and molding a reflective material into the groove to form a convex reflective structure, such that at least part of the convex reflective structure fills the groove, thereby forming an encapsulated LED chip; or, providing a prefabricated optical structure including a convex reflective structure, and aligning and fixing the prefabricated optical structure to the side of the phosphor layer opposite to the LED chip by alignment molding or pressing, thereby forming an encapsulated LED chip; the convex reflective structure is prepared by dispensing.

[0006] Preferably, a flip-chip structure is provided, specifically comprising: providing a substrate with a plurality of cutouts and LED chips; flip-chipping the LED chips onto the substrate, with each LED chip corresponding to one of the cutouts; coating the cutouts on the substrate and the side of the substrate on which the LED chips are disposed with reflective adhesive; and leveling the reflective adhesive on the cutouts and the side of the substrate on which the LED chips are disposed by centrifugation or stencil printing, thereby forming a first reflective layer and a second reflective layer respectively; and molding a phosphor layer onto the side of the second reflective layer and the LED chips facing away from the substrate to obtain the flip-chip structure.

[0007] Preferably, a flip-chip structure is provided, wherein the flip-chip structure includes a substrate, an LED chip, and a phosphor layer arranged sequentially, and the method further includes: molding a transparent layer on the phosphor layer; forming a groove aligned with the LED chip on the side of the phosphor layer opposite to the LED chip by dispensing or printing, specifically including: forming a groove aligned with the LED chip on the side of the transparent layer opposite to the LED chip by dispensing or printing.

[0008] Preferably, a groove aligned with the LED chip is formed on the side of the transparent layer opposite to the LED chip by dispensing adhesive. Specifically, this includes dispensing adhesive onto the transparent layer to form an annular adhesive ring of a preset height, such that the unadhesive area of ​​the inner ring of the annular adhesive ring is recessed towards the LED chip to form the groove, and the center of the recess is aligned with the center of the LED chip.

[0009] Preferably, a groove aligned with the LED chip is formed on the side of the transparent layer opposite to the LED chip by printing. Specifically, this includes: applying a transparent adhesive layer of a predetermined height at each of the four azimuth angles of each opening in the stencil using a stencil and vacuum printing method, and making the boundary of each transparent adhesive layer concave; the concave boundaries of the transparent adhesive layers at the four azimuth angles enclose the area on the transparent layer where no transparent adhesive layer is applied, forming the groove, and aligning the center of the groove with the center of the LED chip.

[0010] Preferably, the prefabricated optical structure is obtained through the following steps: providing a release film or a reflective substrate, forming multiple convex reflective structures arranged in a preset array on the release film or reflective substrate by dispensing adhesive; aligning the multiple convex reflective structures with multiple cutouts in the substrate; molding a transparent layer on the side of the release film or reflective substrate where the convex reflective structures are formed, and completely encapsulating the convex reflective structures through the transparent layer to form the prefabricated optical structure.

[0011] Preferably, the pre-fabricated optical structure is fixed to the side of the fluorescent adhesive layer opposite to the LED chip by alignment molding to form an encapsulated LED bead. Specifically, this includes: setting a first alignment mark point and a second alignment mark point on the flip chip structure and the pre-fabricated optical structure, respectively; providing a molding die including the first alignment structure and the second alignment structure, inserting the first alignment structure and the second alignment structure into the corresponding first alignment mark point and the second alignment mark point, respectively, so that the convex reflective structure is aligned with the LED chip; using the molding die to invert the pre-fabricated optical structure on the side of the fluorescent adhesive layer opposite to the LED chip, and using transparent silicone to bond the pre-fabricated optical structure and the fluorescent adhesive layer to form the encapsulated LED bead.

[0012] Preferably, the pre-fabricated optical structure is aligned and fixed on the side of the fluorescent adhesive layer away from the LED chip by pressing to form an encapsulated LED bead. Specifically, this includes: providing a pressing fixture, directly aligning and bonding the transparent layer of the pre-fabricated optical structure with the fluorescent adhesive layer using the pressing fixture and transparent silicone, and aligning the convex reflective structure with the LED chip to form an encapsulated LED bead.

[0013] Preferably, the substrate is one of a sheet substrate, a flat plate support, and a cup mouth support.

[0014] To solve the above-mentioned technical problems, the present invention also provides a packaged LED bead, which is manufactured using the packaged LED bead preparation method described in any of the preceding claims.

[0015] Compared with the prior art, the method for preparing the encapsulated LED chip and the encapsulated LED chip provided by the present invention have the following advantages: 1. This invention provides a method for preparing an encapsulated LED chip, comprising the following steps: providing a flip-chip structure; the flip-chip structure includes a substrate, an LED chip, and a phosphor layer arranged sequentially; forming a groove aligned with the LED chip on the side of the phosphor layer away from the LED chip by dispensing or printing, and molding a reflective material within the groove to form a convex reflective structure, such that at least part of the convex reflective structure fills the groove, thereby forming an encapsulated LED chip; or, providing a prefabricated optical structure including a convex reflective structure, and aligning and fixing the prefabricated optical structure on the side of the phosphor layer away from the LED chip by alignment molding or pressing, thereby forming an encapsulated LED chip. The method involves first forming a groove, then molding a reflective material based on the shape of the groove to form a convex reflective structure; or prefabricating a convex reflective structure by dispensing to obtain a prefabricated optical structure. In both of these methods, no special mold is used to prepare the convex reflective structure; instead, a lower-cost method, such as dispensing, is employed. Therefore, the above-mentioned preparation method is more cost-effective than the prior art which uses a special mold to prepare the concave reflective structure. In addition, by avoiding the use of molds to prepare non-planar reflective structures, the low demolding efficiency and alignment problems between non-planar reflective structures and LED chips are also avoided.

[0016] 2. The flip-chip structure provided in this invention specifically includes: providing a substrate with a plurality of cutouts and LED chips; flip-chipping the LED chips onto the substrate, with each LED chip corresponding to a cutout; coating the cutouts of the substrate and the side of the substrate where the LED chips are located with reflective adhesive; and leveling the reflective adhesive on the cutouts and the side of the substrate where the LED chips are located by centrifugation or stencil printing, forming a first reflective layer and a second reflective layer respectively; and molding a phosphor layer onto the side of the second reflective layer and the LED chips facing away from the substrate to obtain the flip-chip structure. By setting the first reflective layer in the cutouts of the substrate and the second reflective layer on the side of the substrate where the LED chips are located, a reflective structure can be set at the bottom and periphery of the chip. The diffuse reflection of the light emitted by the LED chips achieved by the first and second reflective layers replaces the total internal reflection of the pad silver plating layer in existing flip-chip light-emitting structures, thereby reducing the high-light interference caused by total internal reflection, making the light scatter uniformly, and resulting in a softer and more natural overall light effect.

[0017] 3. The present invention provides a flip-chip structure, which includes a substrate, an LED chip, and a phosphor layer arranged sequentially. The method further includes: molding a transparent layer on the phosphor layer; forming a groove aligned with the LED chip on the side of the phosphor layer away from the LED chip by dispensing or printing. Specifically, this includes forming a groove aligned with the LED chip on the side of the transparent layer away from the LED chip by dispensing or printing. By setting a transparent layer on the phosphor layer, the light emitted from the top of the LED chip enters the transparent layer after passing through the phosphor layer, thereby better opening the optical angle. Furthermore, after some light is reflected by the white cover, the light is reflected horizontally to pass through the transparent layer and exit, further opening the optical angle.

[0018] 4. The present invention involves forming a groove aligned with the LED chip on the side of the transparent layer opposite to the LED chip using an adhesive dispensing method. Specifically, this includes: dispensing adhesive onto the transparent layer to form an annular ring of a predetermined height, causing the inner ring of the annular ring without adhesive to recess towards the LED chip to form a groove, and aligning the center of the recess with the center of the LED chip. This adhesive dispensing method allows for direct formation of the corresponding groove on the transparent layer, and it offers greater flexibility, enabling control over the size of the formed groove to better meet different parameter requirements for convex reflective structures.

[0019] 5. The method of forming a groove aligned with the LED chip on the side of the transparent layer opposite to the LED chip by printing in this invention specifically includes: applying a transparent adhesive layer of a predetermined height at each of the four azimuth positions of each opening in the stencil using a stencil and vacuum printing method, ensuring that the boundary of each transparent adhesive layer is concave; enclosing the area on the transparent layer without transparent adhesive layer by the concave boundaries of the transparent adhesive layers at the four azimuth positions, forming a groove, and aligning the center of the groove with the center of the LED chip. The groove formed by stencil and vacuum printing allows for direct formation on the transparent layer using a common printing mold, avoiding the demolding problems and high costs associated with using special templates to form convex reflective structures. Furthermore, the stencil and vacuum printing method produces grooves with better consistency and faster speed, making it more suitable for large-scale production.

[0020] 6. The prefabricated optical structure in this invention is obtained through the following steps: providing a release film or a reflective substrate; forming multiple convex reflective structures arranged in a preset array on the release film or reflective substrate by dispensing adhesive; aligning the multiple convex reflective structures with multiple cutouts in the substrate; molding a transparent layer on the side of the release film or reflective substrate where the convex reflective structures are formed, completely encapsulating the convex reflective structures to form the prefabricated optical structure. By dispensing adhesive, convex reflective structures aligned with the cutouts in the substrate can be directly formed on the release film or reflective substrate. Molding a transparent layer onto the convex reflective structures allows for the complete encapsulation of all individual and overall convex reflective structures arranged in a preset array by the transparent layer. After molding, the release film can be directly removed or the structure can be used directly as the prefabricated optical structure, avoiding the cost and demolding problems associated with existing methods that require specially made templates to prepare convex reflective structures. In addition, the separate fabrication of the prefabricated optical structure can avoid errors that may occur during the direct fabrication of the convex reflective structure on the fluorescent adhesive layer, and facilitates the direct use of the intact prefabricated optical structure to fabricate the encapsulated LED beads.

[0021] 7. The present invention uses alignment molding to fix the prefabricated optical structure onto the side of the phosphor layer away from the LED chip to form an encapsulated LED bead. Specifically, this includes: setting a first alignment mark point and a second alignment mark point on the flip chip structure and the prefabricated optical structure, respectively; providing a molding die including the first alignment structure and the second alignment structure; inserting the first alignment structure and the second alignment structure into the corresponding first alignment mark point and second alignment mark point, respectively, so that the convex reflective structure is aligned with the LED chip; pressing the prefabricated optical structure upside down onto the side of the phosphor layer away from the LED chip using the molding die; and using transparent silicone to bond the prefabricated optical structure and the phosphor layer, forming the encapsulated LED bead. By setting the first alignment mark point and the second alignment mark point on the prefabricated optical structure and the substrate, the alignment of each convex reflective structure on the prefabricated optical structure with the LED chip on the substrate can be achieved through the molding die, thereby improving the accuracy of the alignment between the convex reflective structure and the LED chip.

[0022] 8. The present invention uses a pressing method to align and fix the prefabricated optical structure onto the side of the fluorescent adhesive layer facing away from the LED chip to form an encapsulated LED bead. Specifically, this includes: providing a pressing fixture; using the pressing fixture and transparent silicone to directly align and bond the transparent layer of the prefabricated optical structure to the fluorescent adhesive layer; and aligning the convex reflective structure with the LED chip to form the encapsulated LED bead. This pressing method provides a simpler and more efficient way to combine the prefabricated optical structure with the flip-chip light-emitting structure, thus improving production efficiency.

[0023] 9. The present invention also provides a display module, which has the same beneficial effects as the above-described method for preparing encapsulated LED beads, and will not be described in detail here. Attached Figure Description

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

[0025] Figure 1 This is a flowchart of the steps in the preparation method of the encapsulated LED bead provided in the first embodiment of the present invention.

[0026] Figure 2 This is a cross-sectional schematic diagram of the flip-chip structure provided in the method for preparing packaged LED beads according to the first embodiment of the present invention.

[0027] Figure 3 This is a cross-sectional view of the encapsulated LED bead provided in the preparation method of the encapsulated LED bead according to the first embodiment of the present invention. Figure 1 .

[0028] Figure 4 This is a flowchart of the steps in the preparation method of the encapsulated LED bead provided in the second embodiment of the present invention.

[0029] Figure 5 This is a cross-sectional schematic diagram of the prefabricated optical structure provided in the method for preparing the encapsulated LED bead according to the second embodiment of the present invention. Figure 1 .

[0030] Figure 6 This is a cross-sectional view of the encapsulated LED bead provided in the preparation method of the encapsulated LED bead according to the second embodiment of the present invention. Figure 2 .

[0031] Figure 7 This is a flowchart illustrating the specific steps of step S10 in the method for preparing the encapsulated LED bead provided in the third embodiment of the present invention.

[0032] Figure 8 This is a top view of the substrate provided in the method for preparing the packaged LED bead according to the third embodiment of the present invention.

[0033] Figure 9 This is a flowchart illustrating the specific steps involved in preparing the prefabricated optical structure as part of the method for preparing encapsulated LED beads according to the fourth embodiment of the present invention.

[0034] Figure 10 This is a cross-sectional schematic diagram of the prefabricated optical structure provided in the method for preparing the encapsulated LED bead according to the fourth embodiment of the present invention. Figure 2 .

[0035] Figure 11 This is a cross-sectional view of the packaged LED bead provided in the preparation method of the packaged LED bead according to the fifth embodiment of the present invention. Figure 1 .

[0036] Figure 12 This is a cross-sectional schematic diagram of the packaged LED bead provided in the sixth embodiment of the present invention.

[0037] Explanation of reference numerals in the attached diagram: 1. Flip-chip structure; 2. Pre-fabricated optical structure; 3. Encapsulated LED chips; 10. Groove; 11. Substrate; 12. LED chip; 13. Phosphor layer; 14. Convex reflective structure; 15. First reflective layer; 16. Second reflective layer; 17. Transparent layer; 21. Reflective base film; 111. Hollowed-out section; 112. Positive electrode pad; 113. Negative electrode pad; 116. Cup mouth support; 141. Arc-shaped vertex. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0039] Please see Figures 1-3 The first embodiment of the present invention provides a method for preparing encapsulated LED beads, comprising the following steps: S10: Provide a flip-chip structure 1; the flip-chip structure 1 includes a substrate 11, an LED chip 12 and a phosphor layer 13 arranged sequentially. Specifically, in the flip-chip structure 1, the LED chip 12 is flip-chip mounted on the substrate 11, and the phosphor layer 13 covers all positions of the LED chip 12 except the side connected to the substrate 11, so that the light emitted by the LED chip 12 will be converted by the phosphor layer and emitted as white light.

[0040] S20: A groove 10 aligned with the LED chip 12 is formed on the side of the fluorescent adhesive layer 13 opposite to the LED chip 12 by dispensing or printing, and a convex reflective structure 14 is formed by molding reflective material in the groove 10, so that at least part of the convex reflective structure 14 fills the groove 10, forming an encapsulated LED bead 3; or, Specifically, the alignment of the LED chip 12 and the groove 10 is such that the center of the recess in the groove 10 is directly aligned with the light-emitting center of the LED chip 12. This ensures that the convex vertex of the convex reflective structure 14, which fills the entire groove, is also directly aligned with the light-emitting center of the LED chip 12. The reflective material can be made of a highly reflective material, specifically a mixture of transparent silicone and titanium dioxide. In step S20, the groove 10 is first formed on the phosphor layer 13 by dispensing or printing, with the bottom of the groove 10 aligned with the light-emitting center of the LED chip 12. Then, reflective material is molded onto the side of the phosphor layer facing away from the substrate 11, filling the entire groove 10 and curing it. This forms a convex reflective structure 14 within the groove 10, matching its shape, with the convex vertex of the convex reflective structure 14 aligned with the light-emitting center of the LED chip 12. Furthermore, since the convex reflective structure 14 is made of reflective material, it can block and reflect the light emitted from the LED chip 12 after it has undergone color conversion by the phosphor layer 13. Specifically, the convex reflective structure 14 can reflect the light at the center of the LED chip 12, reflecting the light horizontally to prevent the brightness at the center from being too high, thereby making it easier to open the light emission angle and make the light emission more uniform.

[0041] Optionally, the groove 10 can be an arc-shaped groove 10, so that the convex reflective structure 14 is an arc-shaped reflective structure, and the alignment of the arc-shaped reflective structure with the LED chip is such that the arc vertex 141 of the arc-shaped reflective structure is directly opposite the light-emitting center of the LED chip 12.

[0042] Understandably, in step S20, the solution of forming the groove 10 by first applying adhesive or printing, and then forming the convex reflective structure 14 by molding, thereby obtaining the packaged LED bead 3 with a larger light emission angle, does not involve the fabrication of a special mold. Instead, it is achieved in a lower-cost manner. Therefore, this embodiment reduces the manufacturing cost of the convex reflective structure, thus saving costs. In addition, by avoiding the use of special molds to prepare non-planar reflective structures, it also avoids the low demolding efficiency and alignment problems between non-planar reflective structures and LED chips 12.

[0043] Please see Figures 4-6 The present invention also provides a second embodiment, which provides a method for preparing an encapsulated LED chip, comprising the following steps: S10: Provide a flip-chip structure 1; the flip-chip structure 1 includes a substrate 11, an LED chip 12 and a phosphor layer 13 arranged sequentially. S30: A pre-fabricated optical structure 2 including a convex reflective structure 14 is provided. The pre-fabricated optical structure 2 is aligned and fixed on the side of the fluorescent adhesive layer 13 away from the LED chip 12 by alignment molding or pressing to form an encapsulated lamp bead 3. The convex reflective structure 14 is prepared by dispensing.

[0044] Specifically, the prefabricated optical structure 2 includes a convex reflective structure 14. This convex reflective structure 14 can be made of the same material as the convex reflective structure 14 in step S20. When the prefabricated optical structure 2 is aligned and fixed to the side of the fluorescent adhesive layer 13 away from the LED chip 12 by means of alignment molding or pressing, it is also necessary to align the convex reflective structure 14 in the prefabricated optical structure 2 with the LED chip, that is, to align the convex vertex of the convex reflective structure 14 with the light-emitting center of the LED chip 12. This convex reflective structure 14 can also reflect the light emitted from the light-emitting center of the LED chip 12, reflecting the light in a horizontal direction to prevent the brightness at the center position from being too high, thereby making it easier to open the light emission angle and make the light emission more uniform.

[0045] Understandably, in step S30, the convex reflective structure 14, pre-formed by dispensing, is then aligned and fixed to the side of the fluorescent adhesive layer 13 facing away from the LED chip 12 by alignment molding or pressing to form the encapsulated LED bead 3. Similarly, a special mold is not used to prepare the convex reflective structure 14; instead, a lower-cost method, such as dispensing, is used. Therefore, this embodiment reduces the manufacturing cost of the convex reflective structure, resulting in greater cost savings. Furthermore, by avoiding the use of special molds to prepare the non-planar reflective structure, the low demolding efficiency and alignment problems between the non-planar reflective structure and the LED chip 12 are also avoided.

[0046] Therefore, either step 20 or step S30 can form a convex reflective structure 14 that reflects LED light. Compared to the prior art that uses a special mold to create a concave reflective structure, neither method in this embodiment uses a special mold, resulting in lower manufacturing costs and greater cost savings for the convex reflective structure 14. Furthermore, by avoiding the use of molds to create a non-planar reflective structure, the low demolding efficiency and alignment issues between the non-planar reflective structure and the LED chip 12 are also avoided.

[0047] It should be noted that the convex reflective structure 14 formed by either step 20 or step S30 can reflect LED light, and the manufacturing cost is lower than that of the convex reflective structure 14 in the prior art. Therefore, users can choose the corresponding manufacturing method according to their actual needs. This embodiment does not limit this.

[0048] Please see Figure 6 , Figure 7 and Figure 8 The present invention also provides a third embodiment, which, based on the first or second embodiment, includes step S10 as follows: S101: Provide a substrate 11 with a plurality of cutout portions 111 and an LED chip 12, flip-chip the LED chip 12 onto the substrate 11, and make each LED chip 12 correspond to the cutout portion 111; Specifically, in this embodiment, the substrate 11 can be a sheet substrate 11, which is a hollowed-out copper sheet, and the hollowed-out portion 111 is also called the hollowed-out portion 111. The hollowed-out portion 111 is the gap between the positive electrode pad 112 and the negative electrode pad 113 in the substrate 11. When the LED chip 12 is flip-chip mounted on the substrate 11, the positive and negative electrode pads 113 of the LED chip 12 are respectively soldered to a set of positive electrode pads 112 and negative electrode pads 113 on the substrate 11, and span across the hollowed-out portion 111, so that a gap is formed between the bottom of the LED chip 12 and the substrate 11. In this embodiment, this gap directly connects to the corresponding hollowed-out portion 111.

[0049] S102: Reflective adhesive is coated on the cutout portion 111 of the substrate 11 and the side of the substrate 11 where the LED chip 12 is disposed, and the reflective adhesive is leveled on the cutout portion 111 and the side of the substrate 11 where the LED chip 12 is disposed by centrifugation or stencil printing, and a first reflective layer 15 and a second reflective layer 16 are formed respectively. S103: A layer of phosphor adhesive 13 is molded onto the side of the second reflective layer 16 and the LED chip 12 facing away from the substrate 11 to obtain the flip chip structure 1.

[0050] Specifically, the reflective adhesive can be made from materials such as silicone and titanium dioxide. Reflective adhesive can be applied to one side of the substrate 11 where the LED chip 12 is mounted, as well as inside the cutout portion 111, to form a second reflective layer 16 and a first reflective layer 15. The first reflective layer 15 fills the cutout portion 111, and the second reflective layer 16 is located between the phosphor layer 13 and the substrate 11. The second reflective layer 16 surrounds the LED chip 12 and avoids the side of the LED chip 12 that faces away from the substrate 11. The thickness of the second reflective layer 16 must be less than or equal to the thickness of the LED chip 12 to prevent the second reflective layer 16 from being too high and blocking the light emitted by the LED chip 12. The first reflective layer 15 and the second reflective layer 16 can diffusely reflect the light emitted by the LED.

[0051] Understandably, by setting the second reflective layer 16 on the substrate 11 and surrounding the LED chip 12, and cooperating with the first reflective layer 15 within the cutout portion 111, reflective layers can be set at the bottom and periphery of the chip. This allows the diffuse reflection of light emitted from the LED chip 12 by the first reflective layer 15 and the second reflective layer 16 to replace the total internal reflection of the pad silver plating layer in the existing flip-chip light-emitting structure. This reduces the high-light interference caused by total internal reflection, further increases the overall light emission angle of the prepared packaged LED bead 3, and makes the light scatter uniformly, resulting in a softer and more natural overall light effect. Furthermore, setting the first reflective layer 15 and the second reflective layer 16 on the substrate 11 increases the bonding strength between the substrate 11 and the LED chip 12, and between the phosphor layer 13 and the reflective layer, and prevents sulfidation.

[0052] The present invention also provides a fourth embodiment, which, based on any of the first or third embodiments, further includes the following after step S10: S11: A transparent layer 17 is molded onto the fluorescent adhesive layer 13; Specifically, the transparent layer 17 may be made of transparent silicone or silicone with a small amount of diffusing agent added, and can be used to guide light and open the angle of light. After the light emitted from the LED chip 12 is converted by the phosphor layer 13, the light will pass through the transparent layer 17 to expand the light emission angle, and then be reflected by the convex reflective structure 14 before entering the transparent layer 17 again, so as to expand the angle again in the transparent layer 17.

[0053] S200: A groove 10 aligned with the LED chip 12 is formed on the side of the fluorescent adhesive layer 13 opposite to the LED chip 12 by dispensing or printing, specifically including: S2000: A groove 10 aligned with the LED chip 12 is formed on the side of the transparent layer 17 opposite to the LED chip 12 by dispensing or printing.

[0054] Understandably, after the transparent layer 17 is set, its groove 10 will be correspondingly formed on the transparent layer 17, so that reflective material is molded on the transparent layer 17 to fill the groove 10 on the transparent layer 17, forming a convex reflective structure 14. The light emitted by the LED chip 12 enters the transparent layer 17 for the first time after passing through the phosphor layer 13 for color conversion, so as to better open the optical angle through the transparent layer 17. After some light is reflected by the convex reflective structure 14, the light is reflected in the horizontal direction so as to be emitted again through the transparent layer 17, thereby further increasing the lateral light emission angle of the packaged lamp bead 3, so as to further open the optical angle.

[0055] In a first optional embodiment of forming the groove 10, step S201: forming a groove 10 aligned with the LED chip 12 on the side of the transparent layer 17 opposite to the LED chip 12 by dispensing adhesive, specifically including: S2011: Apply adhesive to the transparent layer 17 to form an annular adhesive ring of a preset height, so that the adhesive-free area of ​​the inner ring of the annular adhesive ring is recessed towards the LED chip 12 to form the groove 10, and align the center of the recess of the groove 10 with the center of the LED chip 12.

[0056] Specifically, during the dispensing process, the adhesive used must be of the same composition as the transparent layer 17, so that the light emitted by the LED has a consistent light-reflecting effect when passing through the transparent layer 17. The preset height can be determined in advance according to the height of the convex reflective structure 14 to be formed, thereby ensuring the reflection effect of the convex reflective structure 14 formed in the groove 10 on the light emitted by the LED chip 12.

[0057] More specifically, when the recessed center of the groove 10 is aligned with the light-emitting center of the LED chip 12, that is, when the recessed center of the groove 10 and the light-emitting center of the LED chip 12 are aligned in a direction perpendicular to the LED chip 12, the convex vertex of the convex reflective structure 14 in the groove 10 is aligned with the light-emitting center of the LED chip 12, thereby ensuring the reflection effect of the convex reflective structure 14 on the light emitted by the light-emitting center of the LED chip 12.

[0058] Understandably, the adhesive dispensing method allows the corresponding groove 10 to be formed directly on the transparent layer 17. Moreover, the adhesive dispensing method is more flexible and can control the size of the formed groove 10, making it easier to meet different parameter requirements for the convex reflective structure 14.

[0059] In a second optional embodiment of forming the groove 10, step S211: forming a groove 10 aligned with the LED chip 12 on the side of the transparent layer 17 opposite to the LED chip 12 by printing, specifically including: S2111: By means of steel mesh and vacuum printing, a transparent adhesive layer of a preset height is applied to the four azimuth positions of each opening of the steel mesh, and the boundary of each transparent adhesive layer is formed into an arc shape. Specifically, in this embodiment, the openings on the stencil can be square, not necessarily the same shape as the convex reflective structure 14. The stencil is aligned with the substrate 11 and placed on the transparent layer 17, ensuring that the center of each opening on the stencil is aligned with the light-emitting center of each LED chip 12 in the flip-chip package. Adhesive is applied to each of the four azimuth angles of each opening, forming a transparent adhesive layer of a predetermined height on the transparent layer 17. The central area is an adhesive-free area, lower than the transparent adhesive layer. The material used for the adhesive can be the same as that used for the transparent layer 17. This predetermined height is also determined in advance based on the height of the convex reflective structure 14 to ensure the reflective effect of the convex reflective structure 14 formed within the groove 10 on the light emitted from the LED chip 12.

[0060] It should be noted that, due to the interaction between liquid molecules and surface tension, the boundary of the transparent adhesive layer forms an arc shape after the adhesive inside the opening comes into contact with the transparent layer 17 and the steel mesh.

[0061] More specifically, after the transparent adhesive layer with an arc shape is formed at the boundary, the steel mesh can be demolded by vacuuming, thereby improving the integrity of the demolding structure, that is, the formed groove 10.

[0062] S2112: The area on the transparent layer 17 where the transparent adhesive layer is not coated is enclosed by the arc-shaped boundaries of the transparent adhesive layer at the four azimuth angles to form the groove 10, and the center of the recess of the groove 10 is aligned with the center of the LED chip 12.

[0063] Specifically, after demolding, all transparent adhesive layers on the transparent layer 17 can be cured so that the arc-shaped boundaries of the transparent adhesive layers at the four azimuth angles of any group enclose the central area, that is, the area on the transparent layer 17 corresponding to an LED chip 12 that is not coated with transparent adhesive, that is, the adhesive-free area. The height of this area is lower than that of the transparent adhesive layer, thereby forming the groove 10.

[0064] Understandably, the groove 10 formed by stencil and vacuum printing can be formed directly on the transparent layer 17 using a general printing mold stencil, avoiding the demolding problem and high cost caused by using a special template to form a convex reflective structure 14. Moreover, the stencil and vacuum printing methods form the groove 10 with better consistency, faster speed, and are more suitable for large-scale production.

[0065] Please see Figure 5 , Figure 9 and Figure 10 Furthermore, the prefabricated optical structure 2 is obtained through the following steps: S301: Provide a release film or reflective substrate 21, and form a plurality of convex reflective structures 14 arranged in a preset array on the release film or reflective substrate 21 by dispensing adhesive; the plurality of convex reflective structures 14 are aligned with a plurality of cutout portions 111 in the substrate 11; Specifically, the reflective substrate 21 can be a reflective film made of reflective paper, silicone, or other materials that can reflect light. The preset array can be arranged in the same way as the cutouts 111 in the substrate 11, so that the cutouts 111 correspond one-to-one with the convex reflective structure 14, thereby facilitating the one-to-one correspondence between the convex reflective structure 14 of the prefabricated optical structure 2 and the LED chip 12 in the flip chip structure 1.

[0066] Optionally, a convex reflective structure 14 can be formed by applying adhesive to the release film, which facilitates the molding of the convex reflective structure 14. Demolding can be completed by tearing, making the demolding process of the convex reflective structure 14 simpler and more efficient, and also ensuring higher demolding integrity.

[0067] Optionally, a convex reflective structure 14 can be formed by applying adhesive to the reflective substrate 21. This facilitates the subsequent combination of the convex reflective structure 14 and the reflective substrate 21 to form a reflective structure, thereby increasing the reflection range of the light emitted from the LED chip 12 and further increasing the lateral light emission angle.

[0068] S302: On the side of the release film or reflective base film 21 where the convex reflective structure 14 is formed, a transparent layer 17 is molded to completely enclose the convex reflective structure 14 through the transparent layer 17, forming the prefabricated optical structure 2.

[0069] Specifically, the prefabricated optical structure 2 also includes a transparent layer 17, which is also made of transparent silicone or silicone with a small amount of diffusing agent added. A transparent layer 17 can be molded onto the formed convex reflective structure 14, so that the transparent layer 17 completely covers the convex side of the convex reflective structure 14, thereby fixing the shape of the convex reflective structure 14 in advance and avoiding deformation of the convex reflective structure 14 during the subsequent pressing process.

[0070] Understandably, by dispensing adhesive, convex reflective structures 14 aligned with the cutouts 111 in the substrate 11 can be directly formed on the release film or reflective substrate 21. A transparent layer 17 is then molded onto the convex reflective structures 14, allowing for both individual and overall encapsulation of all the convex reflective structures 14 arranged in a predetermined array by the transparent layer 17. After molding, the release film can be removed directly, or the structure can be used directly as the prefabricated optical structure 2, avoiding the cost and demolding issues associated with traditional methods that require specially designed templates for fabricating convex reflective structures 14. Furthermore, the separate fabrication of the prefabricated optical structure 2 avoids potential errors that may occur during the direct fabrication of the convex reflective structure 14 on the fluorescent adhesive layer 13, facilitating the direct use of the intact prefabricated optical structure 2 to form the encapsulated LED chip 3.

[0071] In the first optional embodiment where the pre-fabricated optical structure 2 is fixed on the phosphor layer 13, step S311: the pre-fabricated optical structure 2 is fixed to the side of the phosphor layer 13 facing away from the LED chip 12 by alignment molding to form the encapsulated lamp bead 3, specifically including: S3111: A first alignment MARK point and a second alignment MARK point are respectively provided on the flip chip structure 1 and the prefabricated optical structure 2; Specifically, the first alignment mark point is a first set of holes pre-set on the flip chip structure 1, used for positioning between the molding die and the substrate 11. The second alignment mark point is a second set of holes pre-set on the prefabricated optical structure 2, used for positioning between the molding die and the prefabricated optical structure 2.

[0072] S3112: Provide a molding die including a first alignment structure and a second alignment structure, and insert the first alignment structure and the second alignment structure into the corresponding first alignment MARK point and the second alignment MARK point respectively, so that the convex reflective structure 14 is aligned with the LED chip 12. Specifically, before molding the pre-formed optical structure 2 and the fluorescent adhesive layer 13, the molding die needs to connect the pillars that need to be molded together. Specifically, the first alignment structure and the second alignment structure can be inserted into the corresponding first alignment mark point and the second alignment mark point respectively, so as to complete the positioning between the molding die and the flip chip structure 1, as well as the positioning between the molding die and the pre-formed optical structure 2. Then, the molding die is used to align the convex vertex of the convex reflective structure 14 on the pre-formed optical structure 2 with the light-emitting center of the LED chip 12.

[0073] S3113: The pre-made optical structure 2 is inverted onto the side of the fluorescent adhesive layer 13 facing away from the LED chip 12 using the molding die, and the pre-made optical structure 2 and the fluorescent adhesive layer 13 are bonded together using transparent silicone to form the encapsulated LED bead 3.

[0074] Specifically, after the prefabricated optical structure 2 is inverted onto the side of the fluorescent adhesive layer 13 facing away from the LED chip 12 using a molding die, transparent silicone is used to bond the prefabricated optical structure 2 and the fluorescent adhesive layer 13. This allows for a more natural transition between the transparent layer 17 and the transparent silicone at the connection point, enabling light to pass through the connection between the prefabricated optical structure 2 and the fluorescent adhesive layer 13 more naturally. Furthermore, when using transparent silicone to bond the prefabricated optical structure 2 and the fluorescent adhesive layer 13, a vacuum is required to ensure the stability of the bond.

[0075] Understandably, by setting the first alignment mark point and the second alignment mark point on the prefabricated optical structure 2 and the substrate 11 respectively, the alignment of each convex reflective structure 14 on the prefabricated optical structure 2 with the LED chip 12 on the substrate 11 can be achieved by the molding die, thereby improving the accuracy of the alignment between the convex reflective structure 14 and the LED chip 12.

[0076] In the second optional embodiment where the pre-fabricated optical structure 2 is fixed on the phosphor adhesive layer 13, step S321: the pre-fabricated optical structure 2 is aligned and fixed on the side of the phosphor adhesive layer 13 away from the LED chip 12 by pressing to form the encapsulated LED bead 3, specifically including: S3211: Provide a pressing fixture, through which the transparent layer 17 and the fluorescent adhesive layer 13 in the prefabricated optical structure 2 are directly aligned and bonded, and the convex reflective structure 14 is aligned with the LED chip 12 to form the encapsulated lamp bead 3.

[0077] Specifically, the difference between the pressing method and the molding method is that the molding method achieves the bonding between the prefabricated optical structure 2 and the fluorescent adhesive layer 13 by vacuuming, while the pressing method does not use vacuuming, but directly presses the prefabricated optical structure 2 onto the fluorescent adhesive layer 13. This achieves the combination of the prefabricated optical structure 2 and the flip-chip light-emitting structure in a simpler and more efficient way, which is more conducive to improving production efficiency.

[0078] Understandably, in any of the above embodiments, whether the groove 10 is made first and then the convex reflective structure 14 is made, or the convex reflective structure 14 is made first and then the transparent layer 17 is molded, the convex reflective structure 14 can be an arc-shaped reflective structure, that is, the side of the arc-shaped reflective structure corresponding to the LED chip 12 is arc-shaped, so that the arc vertex 141 of the arc-shaped reflective structure is directly opposite the center position of the LED chip 12.

[0079] Please see Figure 6Optionally, when the convex reflective structure formed in any of the above embodiments is an arc-shaped reflective structure, the radius of curvature of the arc surface of the arc-shaped reflective structure is 0.5mm-10mm; the distance D between the arc vertex 141 of the arc-shaped reflective structure and the side of the transparent layer 17 near the substrate 11 (e.g., Figure 6 As shown in Figure D), the thickness is 0.2mm-2.0mm. The thickness h of the arc-shaped reflective structure (as shown in Figure D) is... Figure 6 The value of h is 0.02mm-0.5mm.

[0080] Understandably, when the side of the curved reflective structure facing the LED chip 12 is curved, the radius of curvature of the curved vertex 141 on this side can be controlled to be within the range of 0.5mm-10mm. This allows control over the curvature range of the curved shape protruding into the transparent layer 17, ensuring optimal reflection of the LED chip 12's light-emitting center by the curved surface of the reflective structure. This avoids situations where the curved surface is too curved or not curved enough, failing to reflect the light-emitting center of the chip. Furthermore, by controlling the distance D between the curved vertex 141 on the curved reflective structure and the side of the transparent layer 17 near the substrate 11 to be 0.2mm-2.0mm, the light-guiding effect of the transparent layer 17 on the light emitted by the LED chip 12 is ensured, achieving a balance between the light-guiding effect of the light-transmitting layer and the light-reflecting effect of the curved reflective structure within this distance range. Additionally, by controlling the thickness h of the convex reflective structure 14, it is prevented from being too thick and affecting the overall thickness of the packaged LED bead 3.

[0081] The present invention also provides a fifth embodiment, in which the substrate 11 can be a flat plate support or a cup support 116, based on the first embodiment.

[0082] In one alternative embodiment, a flat plate bracket is used instead of the sheet substrate in the second embodiment, and a second reflective layer 16 is disposed on the sheet substrate. The flat plate bracket also has a cutout portion 111, which is also filled with the first reflective layer 15. This can increase the opening light-emitting angle while reducing manufacturing costs.

[0083] Please see Figure 11 In one optional embodiment, a cup holder 116 is used instead of the substrate 11 in the second embodiment and the first reflective layer 15 is provided on the substrate 11. The cup holder 116 also has a hollow portion 111, which is also filled with the first reflective layer 15. The transparent layer 17 covers the cup mouth of the cup holder 116. This can increase the opening light-emitting angle while reducing lateral light loss and improving light efficiency through the cup holder 116.

[0084] Please see Figure 12The present invention also provides a sixth embodiment, which provides an encapsulated lamp bead 3, which is made by the preparation method of the encapsulated lamp bead 3 described in any one of the first to fifth embodiments, and has the same beneficial effects as the first embodiment. This embodiment will not elaborate on this.

[0085] Understandably, the packaged LED bead 3 in this embodiment includes a flip-chip structure 1, which includes a substrate 11, an LED chip 12, and a phosphor layer 13 arranged sequentially. A convex reflective structure 14 is provided on the phosphor layer 13 facing the LED chip 12, with the arc surface of the convex reflective structure 14 facing the LED chip 12.

[0086] Furthermore, the substrate 11 can be a sheet substrate 11, which is a hollowed-out copper sheet, and the hollowed-out portion 111 is also called the hollowed-out portion 111. The hollowed-out portion 111 is the gap between the positive electrode pad 112 and the negative electrode pad 113 in the substrate 11. When the LED chip 12 is flip-chip mounted on the substrate 11, the positive and negative electrode pads 113 of the LED chip 12 are respectively soldered to a set of positive electrode pads 112 and negative electrode pads 113 on the substrate 11, and span across the hollowed-out portion 111, so that a gap is formed between the bottom of the LED chip 12 and the substrate 11.

[0087] Specifically, the reflective adhesive can be prepared using materials such as silicone and titanium dioxide. Reflective adhesive can be applied to the side of the substrate 11 where the LED chip 12 is located and within the cutout portion 111 to form a second reflective layer 16 and a first reflective layer 15. The first reflective layer 15 fills the cutout portion 111, and the second reflective layer 16 is located between the phosphor layer 13 and the substrate 11. The second reflective layer 16 surrounds the LED chip 12 and avoids the side of the LED chip 12 that faces away from the substrate 11. The thickness of the second reflective layer 16 must be less than or equal to the thickness of the LED chip 12 to prevent the second reflective layer 16 from being too high and blocking the light emitted by the LED chip 12. The first reflective layer 15 and the second reflective layer 16 can diffusely reflect the light emitted by the LED.

[0088] Understandably, by setting the second reflective layer 16 on the substrate 11 and surrounding the LED chip 12, and cooperating with the first reflective layer 15 within the cutout portion 111, reflective layers can be set at the bottom and periphery of the chip. This allows the diffuse reflection of light emitted from the LED chip 12 by the first reflective layer 15 and the second reflective layer 16 to replace the total internal reflection of the pad silver plating layer in the existing flip-chip light-emitting structure. This reduces the high-light interference caused by total internal reflection, further increases the overall light emission angle of the prepared packaged LED bead 3, and makes the light scatter uniformly, resulting in a softer and more natural overall light effect. Furthermore, setting the first reflective layer 15 and the second reflective layer 16 on the substrate 11 increases the bonding strength between the substrate 11 and the LED chip 12, and between the phosphor layer 13 and the reflective layer, and prevents sulfidation.

[0089] Furthermore, a transparent layer 17 is disposed between the phosphor layer 13 and the convex reflective structure 14. The transparent layer 17 may be made of transparent silicone or silicone with a small amount of diffusing agent added, and can be used to guide light and open the light angle. After the light emitted from the LED chip 12 is color-changed by the phosphor layer 13, the light will pass through the transparent layer 17 to expand the light emission angle, and then be reflected by the convex reflective structure 14 before entering the transparent layer 17 again, so as to expand the angle again in the transparent layer 17.

[0090] Furthermore, the thickness H1 of substrate 11 (e.g.) Figure 12 As shown in H1) 0.1mm-0.3mm, the thickness H2 of the second reflective layer 16 (as shown in H1) is 0.1mm-0.3mm. Figure 12 The thickness of H2 shown is 0.01mm-0.2mm, and the thickness of the fluorescent adhesive layer 13 is H3 (as shown). Figure 12 As shown, H3) is 0.2mm-0.6mm, and the thickness H4 of the transparent layer 17 (as shown) Figure 12 The thickness of H4 (as shown) is 0.2mm-3.0mm, and the thickness of the convex reflective structure 14 is 0.02mm-0.5mm.

[0091] Understandably, by controlling the thickness range of each layer in the encapsulated LED bead 3, the overall thickness of the encapsulated LED bead 3 can be ensured as much as possible, thereby reducing the overall volume occupied by the encapsulated LED bead 3 while ensuring the light emission effect. In addition, within this range of layer structure, it can be ensured that each layer achieves the light emission effect within the corresponding range, while making the effects of the three elements more balanced, so as to ensure the maximum effect of opening the light emission angle.

[0092] In one optional embodiment, when the encapsulated LED bead 3 does not have a transparent layer 17, the thickness of the fluorescent adhesive layer 13 is 0.4mm-1.0mm.

[0093] Understandably, when the encapsulated LED chip 3 does not have a transparent layer 17, the phosphor layer can be thickened to a thickness of 0.4mm-1.0mm to ensure that the emission angle is not reduced while having a transparent layer 17. In addition, replacing the transparent layer 17 with a thicker phosphor layer 13 simplifies production.

[0094] In the embodiments provided by this invention, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined based on A. However, it should also be understood that determining B based on A does not mean determining B solely based on A; B can also be determined based on A and / or other information.

[0095] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Those skilled in the art should also recognize that the embodiments described in the specification are optional embodiments, and the actions and modules involved are not necessarily essential to the invention.

[0096] In various embodiments of the present invention, it should be understood that the sequence number of each process does not necessarily imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0097] Compared with the prior art, the method for preparing the encapsulated LED chip and the encapsulated LED chip provided by the present invention have the following advantages: 1. This invention provides a method for preparing an encapsulated LED chip, comprising the following steps: providing a flip-chip structure; the flip-chip structure includes a substrate, an LED chip, and a phosphor layer arranged sequentially; forming a groove aligned with the LED chip on the side of the phosphor layer away from the LED chip by dispensing or printing, and molding a reflective material within the groove to form a convex reflective structure, such that at least part of the convex reflective structure fills the groove, thereby forming an encapsulated LED chip; or, providing a prefabricated optical structure including a convex reflective structure, and aligning and fixing the prefabricated optical structure on the side of the phosphor layer away from the LED chip by alignment molding or pressing, thereby forming an encapsulated LED chip. The method involves first forming a groove, then molding a reflective material based on the shape of the groove to form a convex reflective structure; or prefabricating a convex reflective structure by dispensing to obtain a prefabricated optical structure. In both of these methods, no special mold is used to prepare the convex reflective structure; instead, a lower-cost method, such as dispensing, is employed. Therefore, the above-mentioned preparation method is more cost-effective than the prior art which uses a special mold to prepare the concave reflective structure. In addition, by avoiding the use of molds to prepare non-planar reflective structures, the low demolding efficiency and alignment problems between non-planar reflective structures and LED chips are also avoided.

[0098] 2. The flip-chip structure provided in this invention specifically includes: providing a substrate with a plurality of cutouts and LED chips; flip-chipping the LED chips onto the substrate, with each LED chip corresponding to a cutout; coating the cutouts of the substrate and the side of the substrate where the LED chips are located with reflective adhesive; and leveling the reflective adhesive on the cutouts and the side of the substrate where the LED chips are located by centrifugation or stencil printing, forming a first reflective layer and a second reflective layer respectively; and molding a phosphor layer onto the side of the second reflective layer and the LED chips facing away from the substrate to obtain the flip-chip structure. By setting the first reflective layer in the cutouts of the substrate and the second reflective layer on the side of the substrate where the LED chips are located, a reflective structure can be set at the bottom and periphery of the chip. The diffuse reflection of the light emitted by the LED chips achieved by the first and second reflective layers replaces the total internal reflection of the pad silver plating layer in existing flip-chip light-emitting structures, thereby reducing the high-light interference caused by total internal reflection, making the light scatter uniformly, and resulting in a softer and more natural overall light effect.

[0099] 3. The present invention provides a flip-chip structure, which includes a substrate, an LED chip, and a phosphor layer arranged sequentially. The method further includes: molding a transparent layer on the phosphor layer; forming a groove aligned with the LED chip on the side of the phosphor layer away from the LED chip by dispensing or printing. Specifically, this includes forming a groove aligned with the LED chip on the side of the transparent layer away from the LED chip by dispensing or printing. By setting a transparent layer on the phosphor layer, the light emitted from the top of the LED chip enters the transparent layer after passing through the phosphor layer, thereby better opening the optical angle. Furthermore, after some light is reflected by the white cover, the light is reflected horizontally to pass through the transparent layer and exit, further opening the optical angle.

[0100] 4. The present invention involves forming a groove aligned with the LED chip on the side of the transparent layer opposite to the LED chip using an adhesive dispensing method. Specifically, this includes: dispensing adhesive onto the transparent layer to form an annular ring of a predetermined height, causing the inner ring of the annular ring without adhesive to recess towards the LED chip to form a groove, and aligning the center of the recess with the center of the LED chip. This adhesive dispensing method allows for direct formation of the corresponding groove on the transparent layer, and it offers greater flexibility, enabling control over the size of the formed groove to better meet different parameter requirements for convex reflective structures.

[0101] 5. The method of forming a groove aligned with the LED chip on the side of the transparent layer opposite to the LED chip by printing in this invention specifically includes: applying a transparent adhesive layer of a predetermined height at each of the four azimuth positions of each opening in the stencil using a stencil and vacuum printing method, ensuring that the boundary of each transparent adhesive layer is concave; enclosing the area on the transparent layer without transparent adhesive layer by the concave boundaries of the transparent adhesive layers at the four azimuth positions, forming a groove, and aligning the center of the groove with the center of the LED chip. The groove formed by stencil and vacuum printing allows for direct formation on the transparent layer using a common printing mold, avoiding the demolding problems and high costs associated with using special templates to form convex reflective structures. Furthermore, the stencil and vacuum printing method produces grooves with better consistency and faster speed, making it more suitable for large-scale production.

[0102] 6. The prefabricated optical structure in this invention is obtained through the following steps: providing a release film or a reflective substrate; forming multiple convex reflective structures arranged in a preset array on the release film or reflective substrate by dispensing adhesive; aligning the multiple convex reflective structures with multiple cutouts in the substrate; molding a transparent layer on the side of the release film or reflective substrate where the convex reflective structures are formed, completely encapsulating the convex reflective structures to form the prefabricated optical structure. By dispensing adhesive, convex reflective structures aligned with the cutouts in the substrate can be directly formed on the release film or reflective substrate. Molding a transparent layer onto the convex reflective structures allows for the complete encapsulation of all individual and overall convex reflective structures arranged in a preset array by the transparent layer. After molding, the release film can be directly removed or the structure can be used directly as the prefabricated optical structure, avoiding the cost and demolding problems associated with existing methods that require specially made templates to prepare convex reflective structures. In addition, the separate fabrication of the prefabricated optical structure can avoid errors that may occur during the direct fabrication of the convex reflective structure on the fluorescent adhesive layer, and facilitates the direct use of the intact prefabricated optical structure to fabricate the encapsulated LED beads.

[0103] 7. The present invention uses alignment molding to fix the prefabricated optical structure onto the side of the phosphor layer away from the LED chip to form an encapsulated LED bead. Specifically, this includes: setting a first alignment mark point and a second alignment mark point on the flip chip structure and the prefabricated optical structure, respectively; providing a molding die including the first alignment structure and the second alignment structure; inserting the first alignment structure and the second alignment structure into the corresponding first alignment mark point and second alignment mark point, respectively, so that the convex reflective structure is aligned with the LED chip; pressing the prefabricated optical structure upside down onto the side of the phosphor layer away from the LED chip using the molding die; and using transparent silicone to bond the prefabricated optical structure and the phosphor layer, forming the encapsulated LED bead. By setting the first alignment mark point and the second alignment mark point on the prefabricated optical structure and the substrate, the alignment of each convex reflective structure on the prefabricated optical structure with the LED chip on the substrate can be achieved through the molding die, thereby improving the accuracy of the alignment between the convex reflective structure and the LED chip.

[0104] 8. The present invention uses a pressing method to align and fix the prefabricated optical structure onto the side of the fluorescent adhesive layer facing away from the LED chip to form an encapsulated LED bead. Specifically, this includes: providing a pressing fixture; using the pressing fixture and transparent silicone to directly align and bond the transparent layer of the prefabricated optical structure to the fluorescent adhesive layer; and aligning the convex reflective structure with the LED chip to form the encapsulated LED bead. This pressing method provides a simpler and more efficient way to combine the prefabricated optical structure with the flip-chip light-emitting structure, thus improving production efficiency.

[0105] 9. The present invention also provides a display module, which has the same beneficial effects as the above-described method for preparing encapsulated LED beads, and will not be described in detail here.

[0106] The foregoing has provided a detailed description of a method for preparing a packaged LED chip and the packaged LED chip itself, as disclosed in the embodiments of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention. Any modifications, equivalent substitutions, and improvements made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing an encapsulated LED chip, characterized in that: Includes the following steps: A flip-chip structure is provided; the flip-chip structure includes a substrate, an LED chip, and a phosphor layer arranged sequentially. A groove aligned with the LED chip is formed on the side of the fluorescent adhesive layer away from the LED chip by dispensing or printing, and a reflective material is molded into the groove to form a convex reflective structure, so that at least part of the convex reflective structure fills the groove to form an encapsulated LED bead. or, A prefabricated optical structure including a convex reflective structure is provided. The prefabricated optical structure is aligned and fixed on the side of the fluorescent adhesive layer away from the LED chip by means of alignment molding or pressing to form an encapsulated lamp bead. The convex reflective structure is prepared by dispensing adhesive.

2. The method for preparing the encapsulated LED chip as described in claim 1, characterized in that: Provides flip-chip structures, specifically including: A substrate with a plurality of cutout portions and an LED chip are provided. The LED chip is flip-chip mounted on the substrate, and each LED chip corresponds to one of the cutout portions. Reflective adhesive is applied to the cutout portion of the substrate and the side of the substrate on which the LED chip is disposed. The reflective adhesive is then leveled on the cutout portion and the side of the substrate on which the LED chip is disposed by centrifugation or stencil printing, thereby forming a first reflective layer and a second reflective layer, respectively. A phosphor layer is molded onto the side of the second reflective layer and the LED chip facing away from the substrate to obtain the flip chip structure.

3. The method for preparing the encapsulated LED chip as described in claim 1, characterized in that: After providing a flip-chip structure, the flip-chip structure comprising a substrate, an LED chip, and a phosphor layer sequentially arranged, the method further includes: A transparent layer is molded onto the fluorescent adhesive layer; A groove aligned with the LED chip is formed on the side of the fluorescent adhesive layer opposite to the LED chip by dispensing or printing, specifically including: A groove aligned with the LED chip is formed on the side of the transparent layer opposite to the LED chip by dispensing or printing.

4. The method for preparing the encapsulated LED chip as described in claim 3, characterized in that: A groove aligned with the LED chip is formed on the side of the transparent layer opposite to the LED chip by dispensing adhesive, specifically including: A ring of adhesive with a preset height is formed by applying adhesive to the transparent layer. The inner ring of the ring without adhesive is recessed towards the LED chip to form the groove, and the center of the groove is aligned with the center of the LED chip.

5. The method for preparing the encapsulated LED chip as described in claim 3, characterized in that: A groove aligned with the LED chip is formed on the side of the transparent layer opposite to the LED chip by printing, specifically including: By using stencil and vacuum printing, a transparent adhesive layer of a predetermined height is applied to each of the four azimuth positions of each opening in the stencil, and the boundary of each transparent adhesive layer is concave. The grooves are formed by enclosing the areas on the transparent layer where the transparent adhesive layer is not applied with the concave boundaries of the transparent adhesive layer at the four azimuth angles, and the center of the grooves is aligned with the center of the LED chip.

6. The method for preparing the encapsulated LED chip as described in claim 1, characterized in that: The prefabricated optical structure is obtained through the following steps: A release film or a reflective substrate is provided, and multiple convex reflective structures arranged in a preset array are formed on the release film or reflective substrate by dispensing adhesive; the multiple convex reflective structures are aligned with multiple cutouts in the substrate; On the side of the release film or reflective substrate where the convex reflective structure is formed, a transparent layer is molded to completely enclose the convex reflective structure, thus forming the prefabricated optical structure.

7. The method for preparing the encapsulated LED chip as described in claim 6, characterized in that: The pre-fabricated optical structure is fixed to the side of the fluorescent adhesive layer opposite to the LED chip by alignment molding to form an encapsulated LED bead, specifically including: A first alignment mark point and a second alignment mark point are respectively provided in the flip chip structure and the prefabricated optical structure; A molding die is provided, comprising a first alignment structure and a second alignment structure, wherein the first alignment structure and the second alignment structure are respectively inserted into the corresponding first alignment MARK point and the second alignment MARK point, so that the convex reflective structure is aligned with the LED chip; The pre-fabricated optical structure is inverted onto the side of the fluorescent adhesive layer opposite to the LED chip using the molding die, and the pre-fabricated optical structure and the fluorescent adhesive layer are bonded together using transparent silicone to form the encapsulated LED bead.

8. The method for preparing the encapsulated LED chip as described in claim 6, characterized in that: The pre-fabricated optical structure is aligned and fixed to the side of the fluorescent adhesive layer opposite to the LED chip by pressing, forming an encapsulated LED bead, specifically including: A pressing fixture is provided, through which the transparent layer and the fluorescent adhesive layer in the prefabricated optical structure are directly aligned and bonded together, and the convex reflective structure is aligned with the LED chip to form an encapsulated LED bead.

9. The method for preparing the encapsulated LED chip as described in claim 1, characterized in that: The substrate is one of the following: sheet substrate, flat plate support, and cup mouth support.

10. A packaged LED chip, characterized in that: It is prepared by the method of preparing the encapsulated lamp bead as described in any one of claims 1-9.

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