High-energy-efficiency COB light source structure and manufacturing method thereof

Abstract

The high-energy-efficiency COB light source structure comprises a substrate, a light source area is arranged on the upper surface of the substrate, a plurality of LED chips are arranged in the light source area of the substrate, a circle of box dam rubber ring surrounding the light source area is arranged on the upper surface of the substrate, and a plurality of fluorescent powder rubber layers are laid in the light source area of the substrate. The LED chips are arranged on the substrate, the fluorescent powder glue layer located at the bottommost layer wraps the LED chips, the difference value of the fluorescent powder emission wavelengths of every two adjacent fluorescent powder glue layers is larger than or equal to 50 nm, and the method at least comprises the following steps that a plurality of LED chips are welded in a light source area on the upper surface of the substrate, and a circle of box dam glue ring surrounding the light source area is arranged on the upper surface of the substrate; dispensing first fluorescent powder glue at the light source area of the substrate; rapidly settling fluorescent powder in the first fluorescent powder glue to the bottom of the first fluorescent powder glue by adopting a centrifugal process; dispensing second fluorescent powder glue at the light source area of the substrate; rapidly settling fluorescent powder in the second fluorescent powder glue to the bottom of the second fluorescent powder glue by adopting a centrifugal process; and high-temperature baking.

Description

Technical Field

[0001] The present invention specifically relates to a high energy efficiency COB light source structure and a method for manufacturing the high energy efficiency COB light source structure. Background Art

[0002] With the rapid development of LED technology and its wide application in the field of lighting, the performance requirements for LED light sources are also increasing. Especially for high-power LED light sources, a large amount of heat is generated during operation, which puts higher requirements on the thermal management of LED light sources. In addition, in order to ensure the service life and stability of LED light sources, improving the airtightness of light sources has become one of the research focuses. The traditional COBChip On Board light source structure has high light output efficiency and customized design capabilities, especially in dual-tone lighting, full spectrum and other applications. It has great structural advantages.

[0003] However, because COB light sources generally use blue LEDs to excite phosphor glue mixed with multiple phosphors such as red, yellow, orange, and green, and different types of phosphors have different particle sizes and densities, different types of phosphors will settle irregularly during phosphor coating, resulting in poor batch quality of the light color points of COB light sources, making it difficult to improve the yield rate in COB production. At the same time, because long-wavelength phosphors can absorb the light emitted by short-wavelength phosphors, it can cause serious reabsorption problems, which in turn seriously affects the light efficiency of the light source. In addition, when multiple phosphors are mixed, due to the uneven distribution of the powders, there is also uncontrollability in the proportion of phosphor addition and the final light spectrum in the optimization process of matching spectrum dimming. The high light efficiency and high light consistency of white light COB light sources are the key issues we need to address.

[0004] The present invention is just produced based on the above-mentioned shortcomings. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a high energy efficiency COB light source structure and a method for manufacturing a high energy efficiency COB light source structure, both of which are for improving the light extraction efficiency and heat dissipation efficiency of the COB light source structure.

[0006] The present invention is achieved through the following technical solutions:

[0007] The present invention provides a high-energy-efficiency COB light source structure, comprising a substrate, wherein a light source area is provided on the upper surface of the substrate, a plurality of LED chips are provided in the light source area of ​​the substrate, a dam rubber ring surrounding the light source area is provided on the upper surface of the substrate, a plurality of phosphor adhesive layers are laid in the light source area of ​​the substrate, the phosphor adhesive layer located at the bottom layer wraps the LED chip, the phosphor emission wavelength of the phosphor adhesive layer located at the upper layer is shorter than the phosphor emission wavelength of the phosphor adhesive layer located at the lower layer, and the difference in the phosphor emission wavelengths of the phosphors of two adjacent phosphor adhesive layers is greater than or equal to 50nm.

[0008] In the high-efficiency COB light source structure as described above, the phosphor glue layer has at least two layers, namely a first phosphor glue and a second phosphor glue.

[0009] In the high-efficiency COB light source structure as described above, the phosphor glue layer has at least three layers, namely, a first phosphor glue, a second phosphor glue and a third phosphor glue.

[0010] In the high-efficiency COB light source structure as described above, the thickness of the phosphor glue layer at the lowest layer is greater than or equal to 200um, and the thickness of the phosphor glue layer at the top layer is greater than or equal to 300um, and the phosphor glue layer is formed by mixing glue and phosphor, and the phosphor glue layer is a layered structure in which the phosphor is located in the lower layer and the glue is located in the upper layer by a centrifugal process.

[0011] The present invention also provides a method for manufacturing a high energy efficiency COB light source structure, which is used to manufacture the above-mentioned high energy efficiency COB light source structure, comprising the following steps:

[0012] S1. Weld a number of LED chips in the light source area on the upper surface of the substrate, and set a dam rubber ring surrounding the light source area on the upper surface of the substrate;

[0013] S2, applying a first phosphor glue on the light source area of ​​the substrate so that the first phosphor glue covers the entire light source area and the LED chip;

[0014] S3, using a centrifugal process to quickly settle the phosphor in the first phosphor glue to the bottom of the first phosphor glue, so that the phosphor in the first phosphor glue covers the surface of the light source area of ​​the chip and the substrate;

[0015] S4, applying a second phosphor glue on the light source area of ​​the substrate so that the first phosphor glue covers the upper surface of the first phosphor glue;

[0016] S5, using a centrifugal process to quickly settle the phosphor in the second phosphor glue to the bottom of the second phosphor glue, so that the phosphor in the second phosphor glue covers the upper surface of the first phosphor glue;

[0017] S6. High temperature baking makes the product completely solidified.

[0018] The method for manufacturing a high energy efficiency COB light source structure as described above further includes the following steps between step S5 and step S6:

[0019] S5a, heating to pre-cure the second phosphor glue;

[0020] S5b, applying a third phosphor glue on the light source area of ​​the substrate so that the third phosphor glue covers the entire light source area and the LED chip;

[0021] S5c, using a centrifugal process to quickly settle the phosphor in the third phosphor glue to the bottom of the third phosphor glue, so that the phosphor in the third phosphor glue covers the upper surface of the second phosphor glue.

[0022] The method for manufacturing a high-efficiency COB light source structure as described above further includes the following steps between step S3 and step S4: S3a, heating to pre-cure the first phosphor glue.

[0023] In the method for manufacturing the high energy efficiency COB light source structure as described above, step S5 also includes the following sub-steps:

[0024] S31, low-speed centrifugation, with a centrifugal speed of less than or equal to 300 revolutions and a time of less than or equal to 100 seconds, so that the first phosphor glue flows evenly under the action of centrifugal force, and the phosphor in the first phosphor glue is evenly distributed;

[0025] S32, high-speed centrifugation, with a centrifugal speed greater than or equal to 1000 revolutions and a time greater than or equal to 100 seconds, to allow the phosphor in the first phosphor glue to quickly settle to the bottom;

[0026] In the method for manufacturing a high energy efficiency COB light source structure as described above, between step S2 and step S3, the high energy efficiency COB light source structure is preheated.

[0027] In the method for manufacturing the high energy efficiency COB light source structure as described above, between step S2 and step S3, a heating device is used to heat the high energy efficiency COB light source structure to a temperature between 50-70° C.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] 1. The energy-efficient COB light source structure and the manufacturing method thereof of the present invention enable the COB light source structure to have a double-layer or multi-layer phosphor glue, a crystal fixing groove is formed by a dam rubber ring, glue is dispensed in the groove to form a glue layer, and a part of the phosphor glue layer is centrifuged after the dispensing process so that the phosphor of the layer settles to the bottom to form a layered structure, and this layered structure is formed by preheating and locally curing each layer of phosphor glue, and a pre-cured film is formed on the surface of each layer of phosphor glue, and after the subsequent manufacturing of the phosphor glue layer, centrifugation is also performed. Due to the presence of the pre-cured film in the previous process, the phosphor can be blocked on the surface of the pre-cured film in the subsequent process, thereby realizing a uniform layered design of multiple layers of phosphor, and the rapidly precipitated phosphor can be evenly distributed at the interface, with good light consistency and a high yield rate.

[0030] 2. By controlling the emission wavelength of the phosphors in each layer of phosphor glue, the rule is that the phosphor emission wavelength of the phosphor glue closer to the LED chip is longer, and the phosphor emission wavelength of the phosphor glue farther away from the LED chip is shorter. By controlling the emission wavelength of the phosphors in each layer of phosphor glue to become shorter and shorter in the direction from close to the LED chip to far away from the LED chip, the wavelength of the light emitted by the phosphor becomes shorter and shorter from bottom to top, which effectively suppresses the decrease in light efficiency caused by the secondary absorption of the upward emitted light by the phosphor located in the upper layer, thereby effectively improving the light output efficiency and heat dissipation efficiency of the light source.

[0031] 3. Since the phosphor glue is heated on the surface after centrifugation, that is, hot air is blown from top to bottom, each layer of phosphor glue is partially cured, and a pre-cured film is formed on the upper surface of each layer of phosphor glue. The lower part of the colloid still has good fluidity. Then, by adopting a high-speed centrifugation process, the phosphors of each layer of phosphor glue can be quickly and evenly settled to the upper surface of the pre-cured film of the phosphor glue in the lower layer. Moreover, a greater centrifugal force is obtained in the high-speed centrifugation process, so that larger particles of phosphor not only settle quickly, but also in the process of high-speed centrifugation, the settled phosphor particles exert a greater force on the pre-cured film of the lower layer under the action of gravity, and it is easier to form an uneven phosphor distribution layer on the surface of the lower phosphor glue, which is conducive to reducing the reflection effect of light irradiated from bottom to top, thereby more conducive to improving the absorption efficiency of phosphor to light, thereby improving the excitation efficiency of phosphor, and helping to improve the overall light effect of the light source.

[0032] 4. The phosphor glue of the high-efficiency COB light source structure of the present invention adopts a layered design, and each layer adopts sedimentation to form a layered structure. Compared with the method of mixing and blending multiple phosphors, this is not only more conducive to the absorption efficiency of various phosphors to light, but also more convenient to adjust the ratio of phosphors in each layer, and then adjust the light output spectrum of the entire light source structure, which is convenient for controlling the light output spectrum of full-spectrum high-quality light sources. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a three-dimensional schematic diagram of the high energy efficiency COB light source structure of the present invention;

[0034] Figure 2 is a cross-sectional schematic diagram of the high energy efficiency COB light source structure of the present invention;

[0035] Figure 3 The manufacturing method and principle of the high energy efficiency COB light source structure of the present invention Figure 1 ;

[0036] Figure 4 The manufacturing method and principle of the high energy efficiency COB light source structure of the present invention Figure 2 ;

[0037] Figure 5 It is a schematic diagram of the principle of the second phosphor glue of the present invention. DETAILED DESCRIPTION

[0038] The invention will be further described below in conjunction with the accompanying drawings:

[0039] The directions described in the specification of the present invention, such as "up", "down", "left", "right", "front", "back", etc., are based on the directions of the drawings and are intended to facilitate the description of the relationship between the various components. They do not indicate the unique or absolute positional relationship between the various components. They are only one of the implementation methods of the invention and are not a limitation on its implementation method.

[0040] The present invention provides a high energy efficiency COB light source structure, such as Figure 1 and Figure 2As shown, it includes a substrate 1, a light source area 10 is provided on the upper surface of the substrate 1, and a plurality of LED chips 2 are provided in the light source area 10 of the substrate 1. A dam rubber ring 3 is provided on the upper surface of the substrate 1 surrounding the light source area 10, so that a solid crystal groove 30 is formed at the light source area 10. The height of the dam rubber ring 3 is relatively high, preferably not less than 0.6 mm. Since the LED chip is easily damaged by water vapor and sulfur and chlorine gas molecules, the dam rubber ring 3 has a thicker packaging glue that has a better blocking effect on water vapor and sulfur and chlorine. In addition, the phosphor is also easily affected by moisture and deteriorated. In theory, the thicker the thickness of the packaging glue, the better the blocking effect on water vapor and sulfur and chlorine. However, considering the production cost and the design of the light source, the thickness is preferably controlled to be above 0.6 mm; the substrate 1 is paved with a plurality of layers of phosphor glue layers 4 in the light source area 10, and the phosphor glue layer 4 located at the bottom layer wraps the LED chip 2, and the difference in the phosphor emission wavelength of the two adjacent phosphor glue layers 4 is greater than or equal to 50nm. As a feasible implementation, for example, in the first layer, the phosphor of the first phosphor glue 41 covers the chip surface and the substrate surface, in the second layer, the phosphor of the second phosphor glue 42 is evenly distributed on the top surface of the first phosphor glue 41, and in the third layer, the phosphor of the third phosphor glue 43 is evenly distributed on the top surface of the second phosphor glue 42; the thickness of the first layer of phosphor glue is not less than 200um, the second layer is not less than 200um, and the last layer is not less than 300um; if there are only two layers, they are not less than 200um and 300um, that is, the thickness of the phosphor glue layer 4 at the bottom layer is greater than or equal to 200um, and the thickness of the phosphor glue layer 4 at the top layer is greater than or equal to 300um.

[0041] The difference in emission wavelength between the upper and lower layers of phosphor is not less than 50nm. For example, the first layer uses fluoride red phosphor with an emission wavelength of 630nm, the second layer uses YAG yellow-green phosphor with an emission wavelength of 560nm, and the third layer uses nitride green phosphor with an emission wavelength of 490nm. The emission wavelength of phosphor refers to the wavelength of light emitted by the phosphor after being excited by light of a specific wavelength (such as ultraviolet light, visible light, etc.). Different phosphors have different emission wavelengths due to their different compositions and structures. These emission wavelengths determine the color of the phosphor's light. Among them, the phosphor glue layer 4 is divided into at least two layers according to the emission wavelength, the first phosphor glue 41 and the second phosphor glue 42. The emission wavelength of the first phosphor glue 41 close to the chip is the longest, so that the longer-wavelength light will not be absorbed by the phosphor in the upper phosphor glue layer 4, reducing the reabsorption between the phosphors in different phosphor glue layers 4; in addition, the red light emitted by the long-wavelength phosphor has a large difference in photon energy from the blue light emitted by the LED, resulting in a much higher heat energy converted by the red light phosphor than the short-wavelength yellow-green light phosphor at similar excitation efficiencies. Therefore, the red light phosphor with high heat generation is placed close to the chip and the substrate for good heat dissipation, while the phosphor with less heat generation is farther away from the substrate, which is more beneficial to the life and reliability of the light source and the phosphor.

[0042] Among them, the brief calculation and comparison of the calorific value of phosphors:

[0043] Take the commonly used 450nm blue LED to excite 550nm yellow-green phosphor and 640nm red phosphor as an example, and calculate based on the same excitation efficiency of 80% for the two phosphors (the actual excitation efficiency of yellow-green phosphor is higher than that of red phosphor), the heat generated by the two phosphors excited by 1mW blue light is:

[0044] Yellow-green powder: 1 / (1240 / 450)*0.8*(1240 / 450-1240 / 550)+0.2=0.34mW

[0045] Red powder: 1 / (1240 / 450)*0.8*(1240 / 450-1240 / 640)+0.2=0.50mW

[0046] It can be seen that the heat energy converted by the red light phosphor is much higher than that of the short-wavelength yellow-green light phosphor, which is nearly 50% higher. In addition, the efficiency of the yellow-green phosphor is higher, while that of the red phosphor is lower, so the difference will be even greater.

[0047] The phosphor glue layer 4 is generally provided with two or three layers. When two phosphor glue layers 4 are provided, they are respectively the first phosphor glue 41 and the second phosphor glue 42; when three phosphor glue layers 4 are provided, they are respectively the first phosphor glue 41, the second phosphor glue 42 and the third phosphor glue 43. Figure 1 and attached Figure 2To set three layers of phosphor glue 4, of course, four layers or more can also be set, but due to process limitations, it is recommended to control it to two or three layers as much as possible. In addition, in the full-spectrum light source design with high color rendering index requirements, there may be more than three types of phosphors. At this time, phosphors with emission wavelengths less than 30nm can be mixed together because they have less reabsorption. If the amount of phosphor is relatively small, it is difficult to handle the single powder layer sedimentation process because the concentration of phosphor is too dilute, the uniformity of centrifugal sedimentation is relatively poor, and the cost is too high. Therefore, only phosphor glue with a phosphor mass ratio of more than 20% needs to be made into a single layer, otherwise it only needs to be made according to the above mixing method. When the above-mentioned mixing method is used, several special wavelength phosphors need to be added to the ingredients of the phosphor layer in order to change the ratio of the color coordinates in a small range. At this time, part of the phosphor layer can be made by mixing with other phosphors, especially when the amount of phosphor in this layer is small, it is best to mix it with other single powders. At this time, the two mixed phosphors are not restricted by the wavelength difference of less than 30nm. For example: if we use 560nm yellow-green powder and 630nm red powder, and then add a little 500nm green phosphor with a mass share of less than 10%, this phosphor can be mixed with the 560nm yellow-green powder for operation.

[0048] In addition, the phosphor glue layer 4 is made of a mixture of glue and phosphor. The phosphor glue layer 4 is a layered structure made by a centrifugal process, with the phosphor in the lower layer and the glue in the upper layer. The concentration of the phosphor glue cannot be too thin, that is, the proportion of the phosphor cannot be too low. If the concentration of the phosphor glue is too low, the phosphor will easily settle during the operation, and when dispensing the glue, it will settle and cause the phosphor in the glue layer to be uneven. At the same time, the concentration of the phosphor glue cannot be too thick. If it is too thick, it will make it difficult for the thinner colloid to flow evenly. Therefore, the viscosity range of the phosphor glue is 2000-8000mPa.s.

[0049] In this embodiment, the COB light source should have a color temperature below 5000K and use at least two types of phosphors, and is particularly suitable for a multi-spectrum phosphor structure of three or more types.

[0050] Among them, the substrate 1 can be a normal-mount substrate, using a mirror aluminum COB substrate, or a flip-chip substrate, using a high-reflective ceramic plate or an aluminum substrate with a high-reflective insulating glue. Correspondingly, the LED chip can be a normal-mount chip or a flip-chip chip. In the normal-mount structure, the front side of the LED chip (i.e., the side with the electrode) is mounted on the substrate facing up. This structure is an earlier method; in the flip-chip structure, the LED chip is flipped 180 degrees so that the back side of the chip (the side without the electrode) faces up, and the electrode surface directly contacts the substrate.

[0051] For the manufacturing method of the above-mentioned high-efficiency COB light source structure, please refer to the attached Figure 3 and 4 , including the following steps:

[0052] S1, soldering a plurality of LED chips 2 in the light source area 10 on the upper surface of the substrate 1, setting a dam rubber ring 3 surrounding the light source area 10 on the upper surface of the substrate 1, and forming a die-fixing groove 20 in the light source area 10;

[0053] S2. Apply the first phosphor glue 41 on the light source area 10 of the substrate 1, that is, fill the first phosphor glue 41 in the solid crystal groove 20, so that the first phosphor glue 41 covers the entire light source area 10 and the LED chip 2; in this step, apply the long-wavelength phosphor glue (red pink glue) to the light source area and cover the chip. The glue surface needs to be higher than the surface of the chip, and the height difference is not less than 100um. Because the glue is relatively thin, in order to improve the uniformity of the glue distribution, it is planned to use a fine glue head (the glue head aperture is not more than 600um) to evenly apply the phosphor glue in the COB light source area, and perform low-temperature heating on the COB light source to improve the rapid and uniform flow of the phosphor glue. The heating temperature is controlled between 50-70°C.

[0054] S3, using a centrifugal process to quickly settle the phosphor in the first phosphor glue 41 to the bottom of the first phosphor glue 41, so that the phosphor in the first phosphor glue 41 covers the surface of the light source area 10 of the chip and the substrate 1, as shown in FIG. Figure 3 As shown, a first deposition layer 411 of the lower layer and a first upper glue layer 412 are formed, wherein the centrifugal powder precipitation process refers to the process of using the centrifugal force generated by the high-speed rotation of the centrifuge to evenly distribute and settle the phosphor particles in the glue. This process helps to eliminate the agglomeration of phosphor particles and ensure that the phosphor is more evenly distributed in the glue, thereby improving the optical performance of the LED light source;

[0055] S3a, heating to pre-cure the first phosphor glue 41; the heating method uses hot air blowing from above to make the glue on the surface cure quickly, and the glue inside is not cured. The glue inside should have a certain flexibility, the advantage is that it will not be stratified, and the phosphor will not be distributed in a plane, so that the phosphor will absorb light better. The hot air temperature is not lower than 140°C, and the time is 3min-10min.

[0056] S4. Apply the second phosphor glue 42 on the light source area 10 of the substrate 1 so that the first phosphor glue 41 covers the upper surface of the first phosphor glue 41. In this step, continue to apply the medium wavelength phosphor glue (yellow-orange powder glue) to the light source area. The thickness of the phosphor glue is not less than 200um. Because the glue is relatively thin, in order to improve the uniformity of the glue distribution, continue to use a fine glue head combined with substrate heating to improve the ability of the colloid to flow evenly.

[0057] S5, using a centrifugal process to quickly settle the phosphor in the second phosphor glue 42 to the bottom of the second phosphor glue 42, so that the phosphor in the second phosphor glue 42 covers the upper surface of the first phosphor glue 41. The process method can refer to step S3; Figure 5 As shown, a large number of phosphor particles B are deposited on the curing glue surface A, the incident light is P, and the outgoing light is Q. Due to the high speed of the centrifuge, under the greater centrifugal effect, the phosphors of different particles settle differently. Large-particle phosphors are heavier and can settle more, while small particles settle less, which will form an uneven and non-flat surface at the pre-cured surface glue. In this way, the blue light emitted from below includes three types: blue light P1 directly hits the phosphor and excites yellow-orange light, blue light P2 hits the side of the phosphor and reflects to the adjacent phosphor, also exciting yellow-orange light upward, and blue light P3 directly passes through the gap between the phosphors and emits upward. Due to the uneven interface, the downward reflection of blue light by the phosphor is greatly reduced, and the higher absorption efficiency can reduce the amount of phosphor used, further inhibit the reabsorption of light of different wavelengths and phosphors, and help reduce costs.

[0058] S5a, heating to pre-cure the second phosphor glue 42, using the method of step S3a, the heating method is to blow hot air from directly above, so that the glue on the surface is quickly cured, and the glue inside is not cured. The glue inside should have a certain flexibility, the advantage is that it will not be stratified, and the phosphor will not be distributed in a plane, so that the phosphor will absorb light better, the hot air temperature is not lower than 140°C, and the time is 3min-10min.

[0059] S5b, apply the third phosphor glue 43 on the light source area 10 of the substrate 1, so that the third phosphor glue 43 covers the entire light source area 10 and the LED chip 2; continue to apply the short-wavelength phosphor glue (green powder glue) to the light source area, the thickness of this layer of glue should be thicker than the previous layer, not less than 300um, mainly because the thicker glue has better blocking effect on external water vapor, and the thick glue has better protection for the phosphor;

[0060] S5c, using a centrifugal process to quickly settle the phosphor in the third phosphor glue 43 to the bottom of the third phosphor glue 43, so that the phosphor in the third phosphor glue 43 covers the upper surface of the second phosphor glue 42, wherein the process method can refer to step S3;

[0061] S6. High-temperature baking makes the product completely cured. In this step, according to the baking and curing process of the phosphor glue, the light source is placed in an oven for curing to achieve the production of the light source. The curing temperature is greater than 120° C. and the curing time is greater than 1 hour.

[0062] In step S3, the following steps are included, and both step S5 and step S5c can adopt the following steps:

[0063] S31, low-speed centrifugation, with a centrifugal speed of less than or equal to 300 rpm and a time of less than or equal to 100 s, so that the first phosphor glue 41 flows evenly under the action of centrifugal force, and the phosphor in the first phosphor glue 41 is evenly distributed;

[0064] S32, high-speed centrifugation, with a centrifugal speed greater than or equal to 1000 revolutions and a time greater than or equal to 100 seconds, to allow the phosphor in the first phosphor glue 41 to quickly settle to the bottom;

[0065] As a preferred solution, after step S2 and before step S3, the high-efficiency COB light source structure is preheated. The specific method is to use a heating device such as an oven or a heating table to preheat the product. Preheating means maintaining the heating temperature between 50-70°C, because the glue layer dispensed in step S2 is in a non-completely cured state, and preheating can increase the fluidity of the glue layer under the non-completely cured condition.

[0066] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A high energy efficiency COB light source structure, characterized in that: The invention comprises a substrate (1), wherein a light source area (10) is provided on the upper surface of the substrate (1), a plurality of LED chips (2) are provided in the light source area (10) of the substrate (1), a dam rubber ring (3) surrounding the light source area (10) is provided on the upper surface of the substrate (1), a plurality of phosphor glue layers (4) are laid in the light source area (10) of the substrate (1), the phosphor glue layer (4) at the bottom layer wraps the LED chip (2), the phosphor emission wavelength of the phosphor glue layer (4) at the upper layer is shorter than the phosphor emission wavelength of the phosphor glue layer (4) at the lower layer, and the difference in the phosphor emission wavelengths of the two adjacent phosphor glue layers (4) is greater than or equal to 50nm.

2. The high energy efficiency COB light source structure according to claim 1, characterized in that: The phosphor glue layer (4) has at least two layers, namely a first phosphor glue (41) and a second phosphor glue (42).

3. The high energy efficiency COB light source structure according to claim 1, characterized in that: The phosphor glue layer (4) has at least three layers, namely a first phosphor glue (41), a second phosphor glue (42) and a third phosphor glue (43).

4. The high energy efficiency COB light source structure according to claim 1, characterized in that: The thickness of the phosphor glue layer (4) at the lowest layer is greater than or equal to 200 um, and the thickness of the phosphor glue layer (4) at the top layer is greater than or equal to 300 um. The phosphor glue layer (4) is formed by mixing glue and phosphor. The phosphor glue layer (4) is a layered structure in which the phosphor is located at the lower layer and the glue is located at the upper layer, which is manufactured by a centrifugal process.

5. A method for manufacturing a high energy efficiency COB light source structure, used to manufacture the high energy efficiency COB light source structure according to claim 1, characterized in that: The following steps are involved: S1. Welding a plurality of LED chips (2) in a light source area (10) on the upper surface of a substrate (1), and providing a dam rubber ring (3) surrounding the light source area (10) on the upper surface of the substrate (1); S2, applying a first phosphor glue (41) on the light source area (10) of the substrate (1) so that the first phosphor glue (41) covers the entire light source area (10) and the LED chip (2); S3, using a centrifugal process to quickly settle the phosphor in the first phosphor glue (41) to the bottom of the first phosphor glue (41), so that the phosphor in the first phosphor glue (41) covers the surface of the light source area (10) of the chip and the substrate (1); S4, spot-coating the second phosphor glue (42) at the light source area (10) of the substrate (1) so that the first phosphor glue (41) covers the upper surface of the first phosphor glue (41); S5, using a centrifugal process to quickly settle the phosphor in the second phosphor glue (42) to the bottom of the second phosphor glue (42), so that the phosphor in the second phosphor glue (42) covers the upper surface of the first phosphor glue (41); S6. High temperature baking makes the product completely solidified.

6. The method for manufacturing a high energy efficiency COB light source structure according to claim 5, characterized in that: Between step S5 and step S6, the following steps are also included: S5a, heating to pre-cure the second phosphor glue (42); S5b, applying a third phosphor glue (43) on the light source area (10) of the substrate (1) so that the third phosphor glue (43) covers the entire light source area (10) and the LED chip (2); S5c, using a centrifugal process to quickly settle the phosphor in the third phosphor glue (43) to the bottom of the third phosphor glue (43), so that the phosphor in the third phosphor glue (43) covers the upper surface of the second phosphor glue (42).

7. The method for manufacturing a high energy efficiency COB light source structure according to claim 5, characterized in that: Between step S3 and step S4, the following steps are also included: S3a, heating to pre-cure the first phosphor glue (41).

8. The method for manufacturing a high-efficiency COB light source structure according to claim 5, characterized in that: Step S5 also includes the following sub-steps: S31, low-speed centrifugation, with a centrifugal speed of less than or equal to 300 revolutions and a time of less than or equal to 100 seconds, so that the first phosphor glue (41) flows evenly under the action of centrifugal force, and the phosphor in the first phosphor glue (41) is evenly distributed; S32, high-speed centrifugation, with a centrifugal speed greater than or equal to 1000 revolutions and a time greater than or equal to 100 seconds, to allow the phosphor in the first phosphor glue (41) to quickly settle to the bottom.

9. The method for manufacturing a high energy efficiency COB light source structure according to claim 5, characterized in that: Between step S2 and step S3, the high energy efficiency COB light source structure is preheated.

10. The method for manufacturing a high energy efficiency COB light source structure according to claim 9, characterized in that: Between step S2 and step S3, a heating device is used to heat the high energy efficiency COB light source structure to a temperature between 50-70°C.

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