Uniform-luminescence CSP flash lamp and manufacturing method thereof

Abstract

The invention discloses a CSP flash lamp capable of uniformly emitting light and a manufacturing method thereof, and the manufacturing method comprises the following steps: S1, providing a UV film, and fixedly arranging at least one LED chip on the UV film; s2, a fluorescent glue film is fixedly arranged on the light-emitting surface of the LED chip, the plane size of the fluorescent glue film is consistent with the size of the light-emitting surface of the LED chip, and then first baking curing is carried out; s3, the periphery of the LED chip is coated with high-reflection white glue, a reflection box dam is formed, and then secondary baking curing is carried out; s4, in an area defined by the high-reflection white glue, a mist glue cake doped with diffusion powder is adopted for film pressing, and a layer of mist glue film covering the surface of the fluorescent glue film is formed; and S5, the semi-finished product subjected to film pressing is subjected to UV irradiation so as to remove the viscosity of the UV film, and the formed product is peeled off from the UV film. According to the method, through the innovative packaging structure design and process, the color temperature difference between the front face and the side face is effectively eliminated, the problems of yellow light spots and blue light leakage of the side face are avoided, and the uniformity and consistency of emergent light are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor optoelectronic technology, specifically to a CSP flash lamp with uniform light emission and its manufacturing method. Background Technology

[0002] With the rapid development of mobile device camera functions, the requirements for the light quality of their built-in LED flash units are becoming increasingly stringent, especially the uniformity of light and color temperature consistency. Chip Scale Package (CSP) flash units are widely used due to their advantages such as small size and high brightness.

[0003] Currently, there are two main processes for processing phosphor adhesive in CSP flash lamp packaging: The first type is the phosphor suspension process. This process involves adding additives or using specific techniques to the phosphor adhesive, causing the phosphor to be evenly dispersed throughout the adhesive after curing. In flashlights using this process, when the blue light emitted by the chip excites the phosphor for light conversion, the difference in optical path results in a lower color temperature (more yellowish) for light emitted from the side and a higher color temperature (more bluish) for light emitted from the front. This color temperature difference between the front and side, after secondary optical design using reflectors or lenses, easily forms persistent yellow spots on the illuminated surface, affecting image quality and leading to customer dissatisfaction.

[0004] The second method is phosphor deposition. In this process, after dispensing the adhesive, centrifugation or similar equipment is used to cause the phosphor to settle to the bottom of the adhesive layer, with a transparent encapsulating adhesive on top. While this process can improve the front-side color temperature to some extent, there is a risk that the phosphor may not completely cover the chip sidewalls after deposition, resulting in strong blue light leaking directly from the chip's sides. This makes the overall light color uniformity of the light source extremely poor, especially in high color temperature products with relatively low phosphor usage, where the "blue ring" or "blue spot" phenomenon on the sides is particularly noticeable, severely impairing light quality.

[0005] Therefore, there is an urgent need in this field for a new method for manufacturing CSP flash lamps to solve the problems of uneven light spot and color inherent in the two traditional processes mentioned above. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a method for manufacturing a CSP flash unit with uniform light emission. This method, through innovative packaging structure design and process, effectively eliminates color temperature differences between the front and sides, avoids yellow light spots and blue light leakage from the sides, and significantly improves the uniformity and consistency of light output.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] This invention provides a method for manufacturing a CSP flash lamp with uniform light emission, comprising the following steps: S1: Provide a UV film, on which at least one LED chip is fixed; S2: A fluorescent adhesive film is fixed on the light-emitting surface of the LED chip, the planar dimensions of the fluorescent adhesive film being consistent with the light-emitting surface dimensions of the LED chip, followed by a first baking and curing process; S3: Coat the LED chip with high-reflectivity white glue to form a reflective dam, and then bake and cure it a second time; S4: In the area surrounded by the high-reflectivity white glue, a fog-like glue cake doped with diffusion powder is used for pressing to form a fog-like glue film covering the surface of the fluorescent glue film. S5: The semi-finished product after molding is subjected to UV irradiation to remove the stickiness of the UV film, and the molded product is peeled off from the UV film.

[0009] Preferably, in step S3 above, the height of the high-reflectivity white adhesive is flush with the surface of the fluorescent adhesive film, together forming a flat lamination substrate.

[0010] Preferably, in step S4 above, the mist-like adhesive film formed by the pressing process has a flat shape, uniform thickness, and the internal diffusion powder material is uniformly distributed.

[0011] The present invention also provides a CSP flash lamp with uniform light emission, the structure of which includes: LED chips; The fluorescent adhesive film is tightly bonded to the light-emitting surface of the LED chip, and its planar dimensions are consistent with those of the chip's light-emitting surface. The highly reflective white adhesive forms a highly reflective dam that surrounds the side of the LED chip, and its surface is flush with the surface of the fluorescent adhesive film. A mist-like adhesive film covers the area enclosed by the fluorescent adhesive film and the high-reflectivity dam, and the mist-like adhesive film contains uniformly dispersed diffusion powder.

[0012] The beneficial effects of this invention are: Uniform light color and no light spots: This invention creatively adopts a composite structure of "fluorescent film (light conversion layer) + frosted film (light homogenizing layer)". The blue light emitted by the LED chip first undergoes numerous refractions and light conversions within the fluorescent film to form preliminary white light. This white light then enters the frosted film, where the uniformly distributed diffuser powder fully scatters and homogenizes the light, completely eliminating the color temperature difference between the front and side sides caused by optical path difference. Therefore, no yellow light spots will be produced after secondary optical design.

[0013] Improved yield and reliability: The matte film process ensures excellent consistency and flatness across all units on the UV film substrate, significantly improving production yield. Simultaneously, the robust matte film layer effectively protects the underlying phosphor film, enhancing the product's mechanical strength and long-term reliability.

[0014] Improved luminous efficiency: The high-reflectivity white glue dam and efficient light-uniforming structure reduce the loss of light absorbed inside the encapsulation, allowing more light to be effectively extracted, thereby improving the overall luminous efficiency of the light source. Attached Figure Description

[0015] Figure 1 This is a product structure diagram of step S1 in the method of this invention; Figure 2 This is a product structure diagram of step S2 in the method of this invention; Figure 3 This is a product structure diagram of step S3 in the method of this invention; Figure 4 yes Figure 3 Top view; Figure 5 This is a product structure diagram of step S4 in the method of this invention; Figure 6 This is a product structure diagram of step S5 in the method of this invention. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention. Example 1

[0017] like Figure 1-6 As shown, the present invention provides a method for manufacturing a CSP flash lamp with uniform light emission, comprising the following steps: S1: Provide a UV film 1, and fix at least one LED chip 2 on the UV film 1.

[0018] S2: A fluorescent film 3 is fixed on the light-emitting surface of the LED chip 2. The planar dimensions of the fluorescent film 3 are consistent with the light-emitting surface dimensions of the LED chip 2. Then, a first baking and curing process is performed.

[0019] S3: High-reflectivity white glue 4 is coated around the LED chip 2 to form a reflective dam, and then a second baking and curing process is performed; the height of the high-reflectivity white glue 4 is flush with the surface of the fluorescent film 3, together forming a flat film substrate.

[0020] S4: In the area enclosed by the high-reflectivity white glue 4, a fog-like glue cake doped with diffusion powder is used for pressing to form a fog-like glue film 5 covering the surface of the fluorescent glue film; the fog-like glue film 5 formed by the pressing process has a flat shape, uniform thickness, and the diffusion powder material inside is uniformly distributed.

[0021] S5: The semi-finished product after molding is subjected to UV irradiation to remove the stickiness of the UV film, and the molded product is peeled off from the UV film 1.

[0022] The CSP flash lamp prepared by this method, after testing, showed that its color temperature ratio between the front and side surfaces was significantly better than that of products prepared by traditional processes, and there were no visible light spots or blue light leakage, resulting in a significant improvement in light quality. Example 2

[0023] like Figure 6 As shown, a CSP flash lamp with uniform light emission includes the following structure: an LED chip 2; a fluorescent film 3, which is tightly attached to the light-emitting surface of the LED chip and has the same planar dimensions as the light-emitting surface of the chip; a high-reflectivity dam formed by a high-reflectivity white adhesive 4, which surrounds the side of the LED chip and has its surface flush with the surface of the fluorescent film; and a fog-like film 5, which covers the area enclosed by the fluorescent film 3 and the high-reflectivity dam, wherein a diffuser powder is uniformly dispersed within the fog-like film 5.

[0024] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method of manufacturing a CSP flash lamp with uniform light emission, characterized by, The method comprises the following steps: S1: providing a UV film and fixing at least one LED chip on the UV film; S2: fixing a fluorescent glue film on the light emitting surface of the LED chip, the planar size of the fluorescent glue film being consistent with the light emitting surface size of the LED chip, and then performing first baking and curing; S3: coating high reflection white glue around the LED chip to form a reflection dam, and then performing second baking and curing; S4: using a fog-shaped glue cake mixed with diffusion powder to press a film in the area surrounded by the high reflection white glue, to form a fog-shaped glue film covering the surface of the fluorescent glue film; S5: performing UV irradiation on the semi-finished product after the film pressing to remove the viscosity of the UV film, and peeling the formed product from the UV film.

2. The method of claim 1, wherein the method further comprises: forming a first dielectric layer on the first surface of the CSP flash; forming a second dielectric layer on the second surface of the CSP flash; and forming a third dielectric layer on the first and second dielectric layers. The height of the high reflection white glue in the step S3 is flush with the surface of the fluorescent glue film, and together forms a flat film pressing substrate.

3. The method of claim 1, wherein the method further comprises: forming a first dielectric layer on the first surface of the CSP flash; forming a second dielectric layer on the second surface of the CSP flash; and forming a third dielectric layer on the first and second dielectric layers. In the step S4, the fog-shaped glue film formed by the film pressing process has a flat shape, uniform thickness, and the internal diffusion powder material is in a uniform distribution state.

4. A CSP flash lamp prepared by the method of any one of claims 1 to 3, characterized by, The method comprises: an LED chip; a fluorescent glue film tightly adhered to the light emitting surface of the LED chip, and having a planar size consistent with the light emitting surface of the chip; a high reflection dam formed by high reflection white glue, surrounding the side surface of the LED chip, and having a surface flush with the surface of the fluorescent glue film; a fog-shaped glue film covering the area surrounded by the fluorescent glue film and the high reflection dam, and having diffusion powder uniformly dispersed in the fog-shaped glue film.

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