White light LED device and preparation method thereof

Abstract

The invention relates to a white light LED device and a preparation method thereof, and the white light LED device comprises a support bowl cup with an open cavity, a first light-emitting chip assembly disposed in the middle of the cavity of the support bowl cup, and a second light-emitting chip assembly disposed around the peripheral side of the first light-emitting chip assembly. The peripheral contour of the first light-emitting chip assembly is in a regular polygon shape, the first light-emitting chip assembly comprises at least three first light-emitting chips, and a gap is formed between every two adjacent first light-emitting chips. A first packaging adhesive layer and a second packaging adhesive layer are further arranged in the support bowl cup, the first packaging adhesive layer is arranged in the middle of a cavity of the support bowl cup and covers the top faces and the inner side faces of the first light-emitting chips and at least partially covers the outer side faces of the first light-emitting chips, and the second packaging adhesive layer fills the remaining space in the cavity of the support bowl cup and wraps the first packaging adhesive layer. According to the white light LED device, two color temperatures are achieved, meanwhile, light loss can be avoided, and the lighting effect is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of LEDs, and in particular to a white light LED device and a preparation method thereof. Background Art

[0002] White LED lighting technology is well known for its wide range of applications. It is based on the working principle of light-emitting diodes (LEDs) and can produce white light that is both bright and energy-efficient. This type of LED uses a combination of specific fluorescent materials and light-emitting chips to efficiently convert electrical energy into light energy to generate white light. White LEDs are not only favored for their long life, low energy consumption and environmental protection, but are also widely used in a variety of lighting devices because of their small size and easy integration.

[0003] Among the various application forms of white light LEDs, there is a design that has the characteristic of adjusting color temperature, allowing flexible switching between multiple color temperatures. The adjustable color temperature range generally extends from 2700K (warm light) to 5700K (cold light). Users can choose the appropriate color temperature mode according to specific needs to adapt to different lighting conditions and visual needs, thereby creating a comfortable and healthy lighting environment.

[0004] Traditional white light LED devices usually set a retaining wall inside the bracket cup to divide the bracket cup into two independent spaces side by side, and encapsulate different encapsulation glue layers in these two spaces to achieve the effect of two color temperatures. However, the existence of the retaining wall may reflect part of the light emitted by the light-emitting chip, resulting in light loss and thus reducing the light efficiency. Therefore, how to achieve two color temperatures in one space while avoiding light loss and ensuring light efficiency is an urgent problem that needs to be solved. Summary of the invention

[0005] Based on this, the purpose of the present invention is to overcome the defects or shortcomings of the prior art. On the one hand, a white light LED device is provided to achieve two color temperatures while avoiding light loss and ensuring light efficiency.

[0006] A white light LED device comprises a support bowl with an open cavity, a first light-emitting chip assembly arranged in the middle of the support bowl cavity, and a second light-emitting chip assembly arranged around the outer peripheral side of the first light-emitting chip assembly; the outer peripheral contour of the first light-emitting chip assembly is a regular polygon, the first light-emitting chip assembly comprises at least three first light-emitting chips, and there is a gap between two adjacent first light-emitting chips; the first light-emitting chip has a top surface and a peripheral side surface, the side of the peripheral side surface facing another first light-emitting chip is an inner side surface, and the side facing the inner side wall of the support bowl is an outer side surface; the support bowl is also provided with a first encapsulation glue layer and a second encapsulation glue layer, the first encapsulation glue layer is arranged in the middle of the support bowl cavity and covers the top surface and inner side surface of each first light-emitting chip and at least partially covers the outer side surface, the second encapsulation glue layer fills the remaining space in the support bowl cavity and covers the first encapsulation glue layer.

[0007] Compared with the prior art, the white light LED device of the present invention divides the cavity of the bracket bowl cup into two areas from the inside to the outside by arranging a first light-emitting chip component in the middle of the bracket bowl cup and arranging a second light-emitting chip component at a position surrounding the outer periphery of the first light-emitting chip component, and respectively encapsulates the two areas with a first encapsulation adhesive layer and a second encapsulation adhesive layer, forming an LED device with a double-layer encapsulation adhesive layer, which can avoid light loss and ensure light efficiency while achieving dual color temperatures.

[0008] In one embodiment, the first light-emitting chips in the first light-emitting chip assembly are arranged end to end to form a regular polygon, and the second light-emitting chip assembly includes at least three second light-emitting chips, and the second light-emitting chips are arranged to form the same regular polygon as the first light-emitting chips.

[0009] In one embodiment, the top surface of the first packaging adhesive layer does not exceed a position in the cavity that is 50 μm away from the cup surface of the bracket bowl.

[0010] In another aspect, the present invention provides a method for preparing a white light LED device, comprising the following steps:

[0011] Install the chip: prepare a support bowl, install the first light-emitting chip assembly in the middle of the support bowl cavity, and install the second light-emitting chip assembly in the support bowl cavity at a position surrounding the outer periphery of the first light-emitting chip assembly, the outer periphery of the first light-emitting chip assembly forms a first area, the first area is a regular polygon, the first light-emitting chip assembly includes at least three first light-emitting chips, and there is a gap between two adjacent first light-emitting chips; the first light-emitting chip has a top surface and an outer peripheral side surface, the side of the outer peripheral side surface facing the other first light-emitting chip is the inner side surface, and the side facing the inner side wall of the support bowl is the outer side surface;

[0012] First glue dispensing: dispensing glue on the first area to form a first fluorescent glue;

[0013] Centrifugation: centrifugally treating the support bowl to diffuse the first fluorescent glue beyond the first area, so that the first fluorescent glue covers the top surface and the inner side surface of each first light-emitting chip, and at least partially covers the outer side surface;

[0014] First heating and curing: heating the first fluorescent glue to cure the glue to form a first encapsulation glue layer;

[0015] Second glue dispensing: dispensing glue to the remaining space in the cavity of the bracket bowl to form a second fluorescent glue;

[0016] Second heating and curing: heating the second fluorescent glue to cure the glue to form a second encapsulation glue layer, wherein the second encapsulation glue layer covers the first encapsulation glue layer.

[0017] Compared with the prior art, the method for preparing a white light LED device of the present invention installs a first light-emitting chip component in the middle position of a bracket bowl and arranges a second light-emitting chip component at a position surrounding the outer periphery of the first light-emitting chip component to divide the cavity of the bracket bowl from the inside to the outside into a first area and a second area, and then encapsulates the first area with a first fluorescent glue, and centrifuges the first fluorescent glue to completely cover the top surface and side surfaces of each first light-emitting chip and partially cover the outer surface of the first light-emitting chip, and then fills the remaining space of the bracket bowl cavity with a second fluorescent glue to form a second encapsulation glue layer that completely covers the first encapsulation glue layer. Finally, the LED device with a double-layer encapsulation glue layer can achieve dual color temperatures while avoiding light loss and ensuring light efficiency.

[0018] In one embodiment, in the chip installation step, the first light-emitting chip assembly includes at least three first light-emitting chips, and each first light-emitting chip is connected end to end to form a regular polygon.

[0019] In one embodiment, there is a gap between two adjacent first light-emitting chips.

[0020] In one embodiment, the width of the gap is less than or equal to 100 μm.

[0021] In one embodiment, in the chip installation step, the second light-emitting chip assembly includes at least three second light-emitting chips (300), and each second light-emitting chip is arranged to form a regular polygon that is the same as each first light-emitting chip.

[0022] In one embodiment, in the first dispensing step, the first fluorescent glue includes a first glue solution, yellow-green fluorescent powder, red fluorescent powder and anti-precipitation powder, and the ratio of each component is first glue solution: yellow-green fluorescent powder: red fluorescent powder: anti-precipitation powder = 11: (7-26): (2-8): (0.05-0.3).

[0023] In one embodiment, the colloidal viscosity of the first glue is 4000-6500 mPa·s.

[0024] In one embodiment, in the centrifugation step, the centrifugal speed of the centrifugal treatment is 600-1200 r / min, and the centrifugal time is 15-60 s.

[0025] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a top view of the support bowl cup on which the first light-emitting chip and the second light-emitting chip are installed in Example 1 of the preparation method of the present invention;

[0027] Figure 2 It is a schematic diagram of the process of the preparation method of the present invention;

[0028] Figure 3 This is a device appearance diagram in which the first encapsulation adhesive layer is raised in the middle of the bracket bowl;

[0029] Figure 4 This is a spectrum diagram of the white light LED device prepared by Example 1 of the preparation method of the present invention;

[0030] Figure 5 This is an appearance diagram of a device with a smooth encapsulation adhesive layer obtained by the preparation method embodiment 1 of the present invention;

[0031] Figure 6 This is a comparison diagram of the state of the first fluorescent glue in Example 1-2 of the preparation method of the present invention before the first heating and curing; Figure 6 (a) is a state diagram of the first fluorescent glue in Example 1; Figure 6 (b) is a state diagram of the first fluorescent glue in Example 2;

[0032] Figure 7 This is a comparison diagram of the state of the first fluorescent glue before the first heating and curing in Example 1 of the preparation method of the present invention and Comparative Examples 1-3; Figure 7 (a) is a state diagram of the first fluorescent glue in Example 1; Figure 7 (b) is a state diagram of the first fluorescent glue in comparative example 1; Figure 7 (c) is a state diagram of the first fluorescent glue in comparative example 2; Figure 7 (d) is a state diagram of the first fluorescent glue in comparative example 3;

[0033] Reference numerals:

[0034] 10. Bracket for bowls and cups;

[0035] 200. a first light-emitting chip;

[0036] 300. a second light-emitting chip;

[0037] A1, first area; A2, second area; C, middle depression area. DETAILED DESCRIPTION

[0038] Dual-color temperature LED devices usually include two types of fluorescent glue, namely high color temperature fluorescent glue and low color temperature fluorescent glue. The two fluorescent glues can emit light of different color temperatures after being excited. In order to accommodate the two fluorescent glues at the same time, traditional white light LED devices usually set a baffle wall in the cavity of the bracket bowl to divide the cavity into two independent parallel spaces, and then encapsulate different fluorescent glues in the two independent spaces to achieve dual color temperature. However, the existence of the baffle wall will reflect part of the light emitted by the light-emitting chip, thereby causing light loss and reducing the light efficiency. In order to eliminate the light loss caused by the baffle wall and reduce the light efficiency while achieving dual color temperature, it is necessary to redivide the cavity of the bracket bowl into two areas after removing the baffle wall, and encapsulate different encapsulation glue layers in these two areas respectively.

[0039] Based on the above-mentioned improved concept, the present invention arranges a first light-emitting chip assembly including multiple first light-emitting chips in the middle position of the bracket bowl cavity to divide the cavity into a first area located in the middle position and a second area surrounding the first area, and then respectively encapsulates different encapsulation glue layers in the first area and the second area to obtain an LED device that can achieve two color temperatures.

[0040] The scheme of the present invention is described in detail below with reference to the accompanying drawings.

[0041] like Figure 1 As shown, an embodiment of the present invention provides a white light LED device, including a support bowl 10 with an open cavity, a first light-emitting chip component arranged in the middle position of the cavity of the support bowl 10, and a second light-emitting chip component arranged around the outer peripheral side of the first light-emitting chip component.

[0042] Specifically, the first light-emitting chip assembly includes four first light-emitting chips 200, and the first light-emitting chip 200 is a hexahedron, which has a top surface and four sides. The side facing another first light-emitting chip 200 among the four sides is the inner side, and the side facing the inner wall of the support bowl 10 is the outer side. The four first light-emitting chips 200 are arranged end to end to form a regular quadrilateral, and there is a gap between two adjacent first light-emitting chips 200, and the gap width is less than or equal to 100μm, preferably 50μm; the inner circumference of the first light-emitting chip 200 encloses a concave middle concave area C. The first area A1 is formed with the outer circumferential contour line enclosed by the four first light-emitting chips 200 as the boundary, and the cavity part outside the first area A1 forms the second area A2.

[0043] The second light-emitting chip assembly includes four second light-emitting chips 300, and the second light-emitting chips 300 are also hexahedrons like the first light-emitting chips 200. The four second light-emitting chips 300 are distributed in the second area A2 and arranged in the same quadrilateral as the four first light-emitting chips 200. The first area A1 is encapsulated with a first encapsulation glue layer (not shown), which fills the middle recessed area C and the gap between two adjacent first light-emitting chips 200, and covers the top surface, inner side surface and at least part of the outer side surface of each first light-emitting chip 200, wherein the coverage range of the first fluorescent glue on the outer side surface is more than 50% of the outer side surface area from the top surface of the first light-emitting chip 200. The second area A2 is encapsulated with a second encapsulation glue layer (not shown), which fills the remaining space outside the first encapsulation glue layer (not shown) in the cavity, and covers the first encapsulation glue layer (not shown), that is, the second encapsulation glue layer covers the top surface and peripheral side surface of the first encapsulation glue layer.

[0044] In this way, by dividing the cavity from the inside to the outside into the first area A1 and the second area A2, and encapsulating the first encapsulation glue layer and the second encapsulation glue layer in the first area A1 and the second area A2 respectively, the light emitted by the first light-emitting chip 200 in the first area A1 sequentially excites the first encapsulation glue layer and the second encapsulation glue layer and is emitted to form a first color temperature light (low color temperature); the light emitted by the second light-emitting chip 300 in the second area A2 excites the second encapsulation glue layer and is emitted to form a second color temperature light (high color temperature), thereby realizing two color temperatures in the cavity of a bracket bowl 10.

[0045] The number of the first light-emitting chip 200 included in the above-mentioned first light-emitting chip assembly can be two, with two first light-emitting chips 200 arranged in parallel, or can be three, five, six, or even more, arranged end to end to form polygons such as regular triangles, regular pentagons, and regular hexagons, which are not limited here.

[0046] In order to prepare the above-mentioned white light LED device, the present invention provides a method for preparing a white light LED device. The preparation method of the present invention is specifically described below through Examples 1-2.

[0047] Example 1

[0048] like Figure 2 As shown, Embodiment 1 of the present invention provides a method for preparing a white light LED device, comprising the following steps:

[0049] S1: Install the chip: prepare the bracket bowl, install the first light-emitting chip component in the middle of the bracket bowl 10 cavity, and install the second light-emitting chip component in the bracket bowl 10 cavity at a position surrounding the outer periphery of the first light-emitting chip component, wherein the outer periphery of the first light-emitting chip component forms a first area A1.

[0050] Specifically, prepare Figure 3 The support bowl cup 10 with an open cavity shown (e.g., 30 μm in length and 30 μm in width) has a first light-emitting component including four first light-emitting chips 200, which are installed in the middle of the cavity. The four first light-emitting chips 200 are arranged end to end in a regular quadrilateral, with a gap between two adjacent first light-emitting chips 200, and the inner circumference of the first light-emitting chips 200 encloses a central recessed area C. The outer circumference of the regular quadrilateral enclosed by the four first light-emitting chips 200 is used as a boundary to form a first area A1, and the part of the cavity surrounding the outer circumference of the first area A1 is a second area A2, in which a second light-emitting chip component is installed, and the second light-emitting chip component includes four second light-emitting chips 300, and the four second light-emitting chips 300 are arranged in the same quadrilateral as the first light-emitting chip component.

[0051] S2: First glue dispensing: dispensing glue on the first area A1 to form a first fluorescent glue;

[0052] Specifically, glue is dispensed at the central position of the first area A1, so that the first fluorescent glue can be evenly diffused around the first area A1 and fill the middle recessed area C and the gap between two adjacent first light-emitting chips 200. The first fluorescent glue includes a first glue liquid, yellow-green fluorescent powder, red fluorescent powder and anti-precipitation powder, and the mass percentage thereof is first glue liquid: yellow-green fluorescent powder: red fluorescent powder: anti-precipitation powder = 11: (7-26): (2-8): (0.05-0.3);

[0053] The first glue is specifically silica gel, and its viscosity is 4000-6500mPa·s; the yellow-green phosphor is specifically yellow-green phosphor with an emission peak wavelength in the range of 520nm-540nm, and its particle size is 10-20μm; the red phosphor is red phosphor with an emission peak wavelength in the range of 640-660nm, and its particle size is 10-20μm. The phosphor with a larger particle size can improve the brightness of the device;

[0054] In this embodiment, the mass percentage of the first glue liquid, yellow-green phosphor, red phosphor and anti-precipitation powder in the first fluorescent glue is first glue liquid: yellow-green phosphor: red phosphor: anti-precipitation powder = 11:13:4:0.1, the viscosity of the first glue liquid is 5500mPa·s, the emission peak wavelength of the yellow-green phosphor is 531nm, and the particle size is 16μm; the emission peak wavelength of the red phosphor is 650nm, and the particle size is 15μm.

[0055] S3: Centrifugation: Centrifuge the support cup 10 to diffuse the first fluorescent glue outside the first area A1, so that the first fluorescent glue covers the top surface and the inner side surface of each first light-emitting chip 200, and at least partially covers the outer side surface.

[0056] In order to make the light emitted by the first light-emitting chip 200 after excitation of the packaging glue layer located in the first area A1 reach the first target color temperature, it is necessary to improve the conversion efficiency of the first light-emitting chip 200 after exciting the packaging glue layer as much as possible. There are usually two ways to improve the excitation conversion efficiency: one way is to increase the amount of fluorescent powder added in the first fluorescent glue, and the other way is to increase the amount of the first fluorescent glue added. However, adding too much fluorescent powder will cause the first fluorescent glue to be too viscous to stir and dispense when preparing it. Therefore, it is more feasible to increase the amount of the first fluorescent glue added to improve the excitation conversion efficiency. However, since the dispensing position is usually at the center of the first area A1 during dispensing so that the first fluorescent glue can be evenly diffused to the first area A1, if the amount of the first fluorescent glue added is increased, it is easy to cause the first packaging glue layer in the first area A1 to accumulate in the middle of the cavity and protrude to the cup surface of the bracket bowl 10, so that the first packaging glue layer cannot be completely covered after the second packaging glue layer is encapsulated, making it difficult to achieve the first target color temperature, and the colloid located in the middle will also protrude from the bracket bowl 10 (such as Figure 3 The circular dotted line position indicates that the device appearance is affected.

[0057] In order to prevent the colloid in the middle of the bowl of the bracket of the LED device from protruding out of the cup surface, after the first dispensing, the first fluorescent glue still in a fluid state is centrifuged to diffuse the first fluorescent glue toward the outer periphery, reduce the thickness of the middle part of the first fluorescent glue, and at the same time make the first fluorescent glue diffused outward completely cover the top surface and the inner side surface of each first light-emitting chip 200, and at least partially cover the outer side surface;

[0058] Specifically, the bracket bowl cup 10 that has completed the first dispensing is symmetrically placed on opposite sides of the centrifuge's rotating axis, so that the central axis of the bracket bowl cup 10 is perpendicular to the centrifuge's rotating axis, and the first fluorescent glue accumulated in the height direction of the bracket bowl cup 10 is reduced by centrifugal action to diffuse outward to the second area A2, so as to reduce the thickness of the colloid in the middle position, thereby avoiding the middle part of the colloid protruding from the cup surface of the bracket bowl cup 10; at the same time, the first fluorescent glue diffused to the second area A2 will completely cover the top surface and inner side surface of each first light-emitting chip 200, and at least partially cover the outer side surface of the first light-emitting chip 200, wherein the coverage range of the first fluorescent glue on the outer side surface is preferably more than 50% of the outer side surface area from the top surface of the first light-emitting chip 200, and by at least partially covering the outer side surface of the first light-emitting chip 200, the contact area between the first fluorescent glue and the first light-emitting chip 200 is increased as much as possible, and the conversion efficiency of the first light-emitting chip 200 after exciting the fluorescent glue is improved, so that the light converted by the first light-emitting chip 200 reaches the first target color temperature.

[0059] The applicant has found through practice that in the centrifugation step, in order to make the first fluorescent glue effectively diffuse outside the first area A1 under the action of centrifugation, but it is necessary to ensure that the fluidity of the colloid after centrifugation is small, so as to minimize the overflow or make the amount of overflowed colloid as equal as possible, so as to maintain the consistency of the device. The key lies in the viscosity of the first glue in the first fluorescent glue, the addition of anti-precipitation powder, and the setting of centrifugal speed and centrifugation time. Specifically, in the first fluorescent glue, the viscosity of the first glue is 4000-6500mPa·s. Although the bulge in the middle of the first fluorescent glue can be avoided after centrifugation, it will also cause the first fluorescent glue to overflow excessively. Therefore, the use of a first glue with a higher viscosity can reduce the flow of the colloid before centrifugation, slow down the overflow of the colloid during the centrifugation process, minimize the overflow, and also ensure the stability of the colloid morphology after centrifugation to maintain the consistency of the device. At the same time, the anti-precipitation powder added to the first fluorescent glue can promote the fluorescent powder to be evenly dispersed in the first glue solution, avoid the aggregation and precipitation of the fluorescent powder in the colloid, and help improve the excitation conversion efficiency of the first light-emitting chip 200. At the same time, the anti-precipitation powder added to the first fluorescent glue can increase the viscosity of the first fluorescent glue, which cooperates with the first glue solution with a viscosity of 4000-6500mPa·s to jointly adjust the viscosity of the first fluorescent glue of the final configuration, ensuring that the first fluorescent glue can be filled into the gap between two adjacent first light-emitting chips 200. In addition, while ensuring that the first fluorescent glue can be effectively diffused during centrifugation, the overflow amount is minimized or the amount of overflowed colloid is made as equal as possible. The centrifugal speed during centrifugation is 600-1200r / min, the centrifugal time is 15-60s, preferably 900r / min, and the centrifugal time is 20s. If the speed is too slow or the centrifugal time is too short, the first fluorescent glue cannot be diffused, affecting the yield; if the speed is too fast or the centrifugal time is too long, the overflow range of the first fluorescent glue may increase, affecting the color coordinates and photoelectric parameters.

[0060] S4: First heating and curing: heating the first fluorescent glue to cure the glue to form a first encapsulation glue layer.

[0061] Specifically, the first glue-doped bracket bowl cup 10 is baked in an oven to heat the first fluorescent glue to solidify it and form a first packaging glue layer, wherein the top surface of the first packaging glue layer does not exceed a position 50 μm away from the cup surface of the bracket bowl cup in the cavity, so as to reserve sufficient height space for the subsequent filling of the second fluorescent glue, and form a double-layer packaging glue layer above the first light-emitting chip assembly. The first light-emitting chip 200 is mixed by two layers of packaging glue, which is beneficial to improving the dimming effect.

[0062] S5: Second glue dispensing: dispensing glue to the remaining space in the bracket bowl cavity to form a second fluorescent glue.

[0063] Specifically, the second area A2 is dispensed with glue for the second time to form a second fluorescent glue, and the second fluorescent glue fills the remaining space of the cavity of the bracket bowl 10, so that the second fluorescent glue completely covers the first packaging glue layer;

[0064] The second fluorescent glue is composed of a second glue liquid, cyan phosphor, yellow-green phosphor and red phosphor, wherein the mass percentage of the second glue liquid, cyan phosphor, yellow-green phosphor and red phosphor is second glue liquid: cyan phosphor: yellow-green phosphor: red phosphor = 11:0.5:2:0.3; wherein the second glue liquid is specifically silica gel, the cyan phosphor is specifically a cyan phosphor with an emission peak wavelength in the range of 480nm-500nm, and its particle size is 8-18μm; the yellow-green phosphor is specifically a yellow-green phosphor with an emission peak wavelength in the range of 520nm-540nm, and its particle size is 10-20μm, and the red phosphor is specifically a red phosphor with an emission peak wavelength in the range of 650nm-670nm, and its particle size is 10-20μm;

[0065] In this embodiment, the emission peak wavelength of the cyan phosphor is 490nm, and the particle size is 13μm; the emission peak wavelength of the yellow-green phosphor is 531nm, and the particle size is 16μm; the emission peak wavelength of the red phosphor is 650nm, and the particle size is 15μm;

[0066] Preferably, in order to ensure that the two packaging adhesive layers have the same bonding force to prevent the adhesive layers from falling off, the first adhesive liquid of the first packaging adhesive layer is the same as the second adhesive liquid of the second packaging adhesive layer.

[0067] S6: Second heating and curing: heating the second fluorescent glue to cure the glue to form a second encapsulation glue layer.

[0068] Specifically, the second glue-doped support cup 10 is baked in an oven to heat the second fluorescent glue to solidify it, thereby forming a second encapsulation glue layer, and the second encapsulation glue layer completely covers the first encapsulation glue layer.

[0069] In this way, by dividing the cavity of the bracket bowl cup 10 from the inside to the outside into the first area A1 and the second area A2, and encapsulating the first encapsulation glue layer and the second encapsulation glue layer in the first area A1 and the second area A2 respectively, the light emitted by the first light-emitting chip 200 in the first area A1 sequentially excites the first encapsulation glue layer and the second encapsulation glue layer and is emitted to form a first color target temperature light; the light emitted by the second light-emitting chip 300 in the second area A2 excites the second encapsulation glue layer and is emitted to form a second color target temperature light, thereby realizing two color temperatures in one space.

[0070] Figure 4 The spectrum of the white light LED device prepared by the above preparation method is shown. Figure 4It can be seen that the white light LED device prepared by the preparation method of the above embodiment can achieve a maximum color temperature of 5700K and a minimum color temperature of 2700. By adjusting the current of the first light-emitting chip 200 in the first area A1 and the second light-emitting chip 300 in the second area A2, any two color temperatures can be achieved within the range of 2700K-5700K. Figure 5 The figure shows the appearance of the white light LED device obtained by the above preparation method. Figure 5 It can be seen that the packaging adhesive of the white light LED device has a smooth appearance.

[0071] Example 2

[0072] Example 2 adopts the same preparation method as Example 1. The only difference between Example 2 and Example 1 is that the centrifugal speeds are different, and the other steps and parameters are the same. Table 1 shows the centrifugal parameters of Example 1 and Example 2:

[0073] Table 1

[0074]

[0075] See also Figure 6 (a) and 6(b), Figure 6 (a) and 6(b) respectively show the morphology of Example 1-2 after the first dispensing is completed and the first fluorescent glue is centrifuged, wherein: Figure 6 Embodiment 1 shown in (a) is a preferred embodiment.

[0076] Depend on Figure 6 As can be seen from Figures 6(a) and 6(b), after the centrifugal treatment, the first fluorescent glue is effectively diffused to the second area A2, so that the bulge in the middle of the colloid is significantly reduced or even eliminated, and the overflowed first fluorescent glue completely covers the top surface and inner side surface of each first light-emitting chip 200, and at least covers more than 50% of the area of ​​its outer side surface.

[0077] Comparative Examples 1-3

[0078] Examples 1-3 adopt the same preparation method as Example 1. The only difference between Comparative Example 1 and Example 1 is that the first fluorescent glue is not centrifuged after the first dispensing in Comparative Example 1, and the other steps and parameters are the same as those in Example 1. The only difference between Comparative Examples 2-3 and Example 1 is that the centrifugal speed and / or centrifugal time are different, and the other steps and parameters are the same as those in Example 1. Table 2 shows the centrifugal parameters of Comparative Examples 1-3:

[0079] Table 2

[0080]

[0081] See also Figure 7 (a)-7(d), Figure 7 (a)-7(d) respectively show the morphology of the first fluorescent glue of Example 1 of the present invention and Comparative Examples 1-3 before the first heating and curing.

[0082] Comparing 7(a) and 7(b), it can be seen that in Example 1, no centrifugation is performed after the first dispensing, and the middle part of the first fluorescent glue is obviously convex (such as Figure 7 (b) as shown by the dotted circle); and in Example 1, after the first dispensing, centrifugal treatment is performed to eliminate the protrusions of the first fluorescent glue, and at the same time, the first fluorescent glue diffused to the second area A2 covers more than 50% of the outer surface area of ​​the first light-emitting chip 200.

[0083] Comparing 7(a) and 7(c), it can be seen that compared with Example 1, under the same centrifugation time condition, the centrifugal speed of Example 2 is lower (less than 600 r / min). Although a small part of the colloid will overflow from the first area A1, the bulge in the middle of the first fluorescent gel is still obvious (such as Figure 7 (c) as shown by the circular dotted line position), and the overflowed small amount of colloid can only cover a very small part of the outer side surface of the first light-emitting chip 200.

[0084] Comparing 7(a), 7(c) and 7(d), it can be seen that compared with Comparative Example 2, the centrifugation time of Comparative Example 3 is shorter (less than 15s), and the colloid has almost no diffusion, so the bulge in the middle of the first fluorescent gel is more obvious than that in Comparative Example 2 (such as Figure 7 (d) The dotted circle position is shown).

[0085] Compared with the prior art, the present invention divides the cavity into a first area located in the middle position and a second area arranged around the first area by arranging a first light-emitting chip component in the middle position of the bracket bowl cavity. The light-emitting chip in the first area is firstly packaged by dispensing glue to form a first fluorescent glue, and then the bracket bowl is centrifuged to allow the first fluorescent glue to diffuse toward the outer peripheral side of the first area and completely cover the top surface and side surfaces of each first light-emitting chip and partially cover the outer side surface of the first light-emitting chip. After centrifugation, the first fluorescent glue is heated and cured to form a first packaging glue layer, and then a second dispensing is performed. After heating and curing, a second packaging glue layer is formed that completely covers the first packaging glue layer, and finally a white light LED device with a smooth packaging glue layer appearance is obtained, and dual color temperatures can be achieved. Furthermore, by adopting a first glue liquid with a higher viscosity and adding anti-precipitation powder to configure the first fluorescent glue, and centrifuging under appropriate centrifugal speed and centrifugal time conditions, it is ensured that the first fluorescent glue can effectively diffuse to cover the outer side surface of the first light-emitting chip during centrifugation, and the overflow is minimized to ensure the consistency of the device as much as possible.

[0086] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of the present application. The singular forms of "a", "said" and "the" used in the embodiments of the present application and the claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that, unless otherwise specified, "multiple" refers to two or more; the terms "first", "second", "third", etc. are only used to distinguish, rather than to describe a specific order or sequence, and cannot be understood as indicating or implying relative importance. The term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items. When the above description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. In the description of the present application, for those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0087] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A white light LED device, characterized in that: It comprises a support cup (10) having an open cavity, a first light-emitting chip component arranged in the middle of the cavity of the support cup (10), and a second light-emitting chip component arranged around the outer periphery of the first light-emitting chip component; The outer peripheral contour of the first light-emitting chip assembly is a regular polygon, the first light-emitting chip assembly comprises at least three first light-emitting chips (200), and there is a gap between two adjacent first light-emitting chips (200); the first light-emitting chip (200) has a top surface and an outer peripheral side surface, the side surface of the outer peripheral side surface facing another first light-emitting chip (200) is an inner side surface, and the side surface facing the inner side wall of the support bowl (100) is an outer side surface; The support bowl (10) is also provided with a first encapsulation adhesive layer and a second encapsulation adhesive layer. The first encapsulation adhesive layer is arranged in the middle of the cavity of the support bowl (10) and covers the top surface and inner side surface of each first light-emitting chip (200) and at least partially covers the outer side surface. The second encapsulation adhesive layer fills the remaining space in the cavity of the support bowl (10) and covers the first encapsulation adhesive layer.

2. The white light LED device according to claim 1, characterized in that: The first light-emitting chips (200) in the first light-emitting chip assembly are arranged end to end to form a regular polygon, and the second light-emitting chip assembly comprises at least three second light-emitting chips (300), and the second light-emitting chips (300) are arranged to form the same regular polygon as the first light-emitting chips (200).

3. The white light LED device according to claim 1, characterized in that: The top surface of the first packaging adhesive layer does not exceed a position within the cavity that is 50 μm away from the cup surface of the support bowl (10).

4. A method for preparing a white light LED device, characterized in that: The following steps are involved: Installing the chip: preparing a support bowl (10), installing a first light-emitting chip assembly in the middle of the cavity of the support bowl (10), and installing a second light-emitting chip assembly in the cavity of the support bowl (10) at a position surrounding the outer periphery of the first light-emitting chip assembly, wherein the outer periphery of the first light-emitting chip assembly forms a first area (A1), and the first area (A1) is a regular polygon; the first light-emitting chip assembly includes at least three first light-emitting chips (200), and there is a gap between two adjacent first light-emitting chips (200); the first light-emitting chip (200) has a top surface and an outer peripheral side surface, wherein the side of the outer peripheral side surface facing the other first light-emitting chip (200) is an inner side surface, and the side facing the inner side wall of the support bowl (100) is an outer side surface; First glue dispensing: dispensing glue on the first area (A1) to form a first fluorescent glue; Centrifugation: centrifugally treating the support cup (10) to diffuse the first fluorescent glue outside the first area (A1), so that the first fluorescent glue covers the top surface and inner side surface of each first light-emitting chip (200) and at least partially covers the outer side surface; First heating and curing: heating the first fluorescent glue to cure the glue to form a first encapsulation glue layer; Second glue dispensing: dispensing glue on the remaining space in the cavity of the support bowl (10) to form a second fluorescent glue; Second heating and curing: heating the second fluorescent glue to cure the glue to form a second encapsulation glue layer, wherein the second encapsulation glue layer covers the first encapsulation glue layer.

5. The method for preparing a white light LED device according to claim 4, characterized in that: In the chip installation step, the first light-emitting chip assembly comprises at least three first light-emitting chips (200), and each first light-emitting chip (200) is connected end to end to form a regular polygon.

6. The method for preparing a white light LED device according to claim 5, characterized in that: There is a gap between two adjacent first light-emitting chips (200).

7. The method for preparing a white light LED device according to claim 6, characterized in that: The width of the gap is less than or equal to 100 μm.

8. The method for preparing a white light LED device according to claim 4, characterized in that: In the chip installation step, the second light-emitting chip assembly comprises at least three second light-emitting chips (300), and each second light-emitting chip (300) is arranged to form a regular polygon that is the same as that of each first light-emitting chip.

9. The method for preparing a white light LED device according to claim 4, characterized in that: In the first dispensing step, the first fluorescent glue includes a first glue solution, yellow-green fluorescent powder, red fluorescent powder and anti-precipitation powder, and the ratio of each component is first glue solution: yellow-green fluorescent powder: red fluorescent powder: anti-precipitation powder = 11: (7-26): (2-8): (0.05-0.3).

10. The method for preparing a white light LED device according to claim 9, characterized in that: The colloidal viscosity of the first glue solution is 4000-6500 mPa·s.

11. The method for preparing a white light LED device according to claim 4, characterized in that: In the centrifugation step, the centrifugal speed of the centrifugal treatment is 600-1200 r / min, and the centrifugal time is 15-60 s.

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