WO2019227993A1

WO2019227993A1 - Light emitting diode packaging structure and packaging method

Info

Publication number: WO2019227993A1
Application number: PCT/CN2019/076644
Authority: WO
Inventors: 陈雨叁; 刘莹莹; 王艳刚
Original assignee: 深圳市绎立锐光科技开发有限公司
Priority date: 2018-06-01
Filing date: 2019-03-01
Publication date: 2019-12-05
Also published as: CN110556464A

Abstract

The present application relates to the field of light emitting diodes, and discloses a light emitting diode packaging structure and packaging method. The packaging structure comprises a first wavelength conversion layer, a second wavelength conversion layer, and a third optical layer; the first wavelength conversion layer is located between the second wavelength conversion layer and a light emitting diode; the side of the second wavelength conversion layer away from the first wavelength conversion layer is provided with the third optical layer, and the third optical layer comprises a light guide layer and/or a third wavelength conversion layer; the first wavelength conversion layer is used for converting light emitted from the light emitting diode into light of a first wavelength, the second wavelength conversion layer is used for converting the light emitted from the light emitting diode into light of a second wavelength, the first wavelength being different from the second wavelength, and the third wavelength conversion layer is used for converting the light emitted from the light emitting diode into light of a third wavelength. By means of the method, the color rendering index of the packaged light emitting diode can be effectively improved and the reliability is ensured.

Description

Light emitting diode packaging structure and packaging method

Technical field

The present application relates to the field of light emitting diodes, and in particular, to a light emitting diode packaging structure and a packaging method.

Background technique

At present, light-emitting diodes, as an energy-saving and environmental-friendly light source, have generally replaced traditional light sources and are widely used in various indoor and outdoor places (such as home interior lighting, shopping mall decorative lighting, stage lighting, outdoor street lights, square lighting, advertising Display boards, building exterior decorative lights, traffic lights, etc.). In the field of white light-emitting diode lighting, people are constantly pursuing high light efficiency and high brightness in order to achieve the highest efficiency in energy conversion and efficiency improvement.

In this development process, there is an increasing demand for high-power and high-brightness applications. As the brightness of high-power light-emitting diodes continues to increase, the process and material requirements for their packaging are gradually increasing. High-power light-emitting diodes can be encapsulated with fluorescent ceramics instead of silicone fluorescent layers or resin fluorescent layers (mixed with phosphor and adhesive). Compared with the organic-encapsulated silicone fluorescent layer or resin fluorescent layer, fluorescent ceramics have better heat dissipation and heat resistance, but lower conversion efficiency. The fluorescent ceramic packaged light emitting diode has better reliability, but still has the problem of low color rendering index.

In order to solve this problem, a packaging structure composed of a red and yellow double-layer fluorescent ceramic bonded is proposed in the prior art. After being excited by the blue light emitted from the light emitting diode, the yellow fluorescent ceramic generates yellow light, and the red fluorescent ceramic generates red light. Blue light that is not excited by the fluorescent ceramic is mixed into white light. The red light in the double-layer fluorescent ceramic packaged light-emitting diode can supplement the missing part of the spectrum, thereby improving the color rendering index, but the conversion efficiency of the fluorescent ceramic is low and it is not easy to control, which makes the light-emitting effect not ideal.

Summary of the Invention

The technical problem mainly solved by the present application is to provide a light emitting diode packaging structure and a packaging method, which can solve the problem of low color rendering index of the light emitting diodes after packaging and ensure reliability.

In order to solve the above technical problems, a technical solution adopted in the present application is to provide a light emitting diode package structure including a first wavelength conversion layer, a second wavelength conversion layer, and a third optical layer; the first wavelength conversion layer is located at Between the second wavelength conversion layer and the light emitting diode; a third optical layer is disposed on a side of the second wavelength conversion layer remote from the first wavelength conversion layer, and the third optical layer includes a light guide layer and / or a third wavelength conversion layer; The first wavelength conversion layer is used to convert light emitted from the light emitting diode into light of a first wavelength, the second wavelength conversion layer is used to convert light emitted from the light emitting diode into light of a second wavelength, the first wavelength and the second wavelength Differently, the third wavelength conversion layer is used to convert light emitted by the light emitting diode into light of a third wavelength.

In order to solve the above technical problem, another technical solution adopted in the present application is: sequentially laminating the first wavelength conversion layer, the second wavelength conversion layer, and the third optical layer on the light emitting diode in sequence; The first wavelength conversion layer, the second wavelength conversion layer, and the third optical layer are stacked together, and then they are bonded and disposed on the light emitting diode, and the first wavelength conversion layer is close to the light emitting diode; the bonding method uses Colorless and transparent optical adhesive bonding; the third optical layer includes a light guide layer and / or a third wavelength conversion layer; the first wavelength conversion layer and the third wavelength conversion layer include at least one of a fluorescent ceramic or a fluorescent glass; a light guide The layer includes at least one of transparent ceramic or glass; the second wavelength conversion layer includes at least one of fluorescent ceramic, fluorescent glass, silica gel fluorescent layer, resin fluorescent layer, and quantum dot film.

The beneficial effects of the present application are: Different from the situation of the prior art, the present application provides a light emitting diode package structure, which includes a first wavelength conversion layer, a second wavelength conversion layer, and a third optical layer; the first wavelength The conversion layer is located between the second wavelength conversion layer and the light emitting diode; a third optical layer is provided on a side of the second wavelength conversion layer away from the first wavelength conversion layer, and the third optical layer includes a light guide layer and / or a third wavelength conversion Layer; wherein the first wavelength conversion layer is used to convert light emitted by the light emitting diode into light of the first wavelength, and the second wavelength conversion layer is used to convert light emitted by the light emitting diode into light of the second wavelength, the first wavelength and The second wavelength is different, and the third wavelength conversion layer is used to convert light emitted from the light emitting diode into light of a third wavelength. Light of a second wavelength different from the first wavelength emitted by the second wavelength conversion layer can make up for the missing part of the spectrum and improve the color rendering index of the packaged light emitting diode. At the same time, the third optical layer can adjust the uniformity of light output on the surface, and can isolate the first wavelength conversion layer and the second wavelength conversion layer from the external environment such as air, and can avoid the first wavelength conversion layer and / or the second wavelength conversion layer. Degradation and failure at higher temperatures improve the reliability of light-emitting diodes, and especially ensure the reliability at higher power and temperature conditions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a first embodiment of a light emitting diode package structure of the present application; FIG.

2 is a schematic structural diagram of a second embodiment of a light emitting diode package structure of the present application;

3 is a schematic structural diagram of a third embodiment of a light emitting diode package structure of the present application;

4 is a schematic structural diagram of a fourth embodiment of a light emitting diode package structure of the present application;

5 is a schematic structural diagram of a fifth embodiment of a light emitting diode package structure of the present application;

6 is a schematic structural diagram of a sixth embodiment of a light emitting diode package structure of the present application;

7 is a schematic flowchart of an embodiment of a light emitting diode packaging method according to the present application;

8 is a schematic flowchart of another embodiment of a light emitting diode packaging method according to the present application;

FIG. 9 is a schematic view showing a packaging solution effect of a prior art light emitting diode; FIG.

FIG. 10 is a schematic view showing an effect of an embodiment of a packaging scheme for a light emitting diode according to the present application.

Detailed ways

In the following, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the embodiments described in the following of the present application are only a part of the embodiments of the present application, not all of them Examples. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

In the following embodiments, those that do not conflict may be combined with each other.

FIG. 1 is a schematic structural diagram of a first embodiment of a light emitting diode package structure of the present application.

As shown in FIG. 1, 101 is a light emitting diode, 102 is a first wavelength conversion layer, 103 is a silica gel fluorescent layer or a resin fluorescent layer, and 104 is a third wavelength conversion layer.

The light emitting diode 101 may be a blue light emitting diode 101, a single light emitting diode 101, a light emitting diode group formed by a plurality of light emitting diodes 101, or other light emitting diodes 101, which is not specifically limited herein.

The first wavelength conversion layer 102 is located between the silicone fluorescent layer or the resin fluorescent layer 103 and the light emitting diode 101. The first wavelength conversion layer 102 is used to convert the light emitted by the light emitting diode 101 into light of the first wavelength. The silicone fluorescent layer or resin The fluorescent layer 103 is used to convert light emitted from the light emitting diode 101 into light of a second wavelength, and the first wavelength is different from the second wavelength.

Light of the first wavelength, light of the second wavelength, and light not emitted by the light emitting diode 101 can be mixed to obtain white light. In general, white light can also be obtained by mixing light of the first wavelength with light that is emitted by the LED 101 and is not absorbed. Compared with the two types of white light, the former adds light of the second wavelength, which can supplement the missing part of the spectrum, thereby improving the color rendering index. For example, the light emitted by the light emitting diode is blue light, the light of the first wavelength may be yellow, and the light of the second wavelength may be red. It can be understood that the first wavelength is smaller than the second wavelength; in this embodiment, the wavelength of the yellow light of the first wavelength is smaller than that of the red light of the second wavelength, and the yellow light in this embodiment cannot excite the red phosphor and the red fluorescence Excited by light with a shorter wavelength emitted by the light emitting diode, specifically blue light or ultraviolet light, etc., thus ensuring a high light efficiency of the entire light emitting device.

The thermal conductivity of the first wavelength conversion layer 102 is greater than that of the silica gel fluorescent layer or the resin fluorescent layer 103, so the heat generated by the silica gel fluorescent layer or the resin fluorescent layer 103 can be diffused through the first wavelength conversion layer 102.

The first wavelength conversion layer 102 includes at least one of a fluorescent ceramic or a fluorescent glass. The fluorescent ceramic layer may be a pure phase fluorescent ceramic layer or a multi-phase fluorescent ceramic layer.

The silica gel fluorescent layer includes silica gel and a phosphor, wherein the silica is used as an adhesive phase to encapsulate the phosphor therein. The fluorescent glass layer includes a fluorescent powder and glass, wherein the glass serves as an adhesive phase to encapsulate the fluorescent powder therein. Pure-phase fluorescent ceramic layers are generally composed of pure-phase fluorescent ceramics, excluding other components as a bonding phase; such as cerium-doped yttrium aluminum garnet pure-phase fluorescent ceramics (YAG: Ce). The multi-phase fluorescent ceramic layer includes a phosphor and a ceramic material, wherein the ceramic material is used as an adhesive phase to encapsulate the phosphor therein, such as a common ceramic material such as alumina, undoped yttrium aluminum garnet, etc .; in some specific embodiments, In this case, the fluorescent ceramic can be YAG: Ce & Al2O3, which is a cerium-doped yttrium aluminum garnet phosphor and alumina as a composite phase fluorescent ceramic. It can be understood that the ratio of silica gel and phosphor in the silicone fluorescent layer can be adjusted, the ratio of phosphor and glass powder in the fluorescent glass layer can be adjusted, the ratio of yttrium aluminum garnet and cerium in the pure phase ceramic layer can be adjusted, and the multi-phase fluorescent ceramic layer The ratio of medium yttrium aluminum garnet, cerium and alumina can be adjusted. It can be adjusted according to the specific color temperature requirements, which will not be repeated here.

Each of the silica gel fluorescent layer or the resin phosphor layer 103 includes a phosphor, the silica gel fluorescent layer includes silica gel, the resin phosphor layer includes a resin, and the phosphor includes at least one of a cyan phosphor, a green phosphor, and a red phosphor. The red phosphor may be a red nitride phosphor such as (Sr, Ca) AlSiN3: Eu2 +. It can be understood that, since the particle size of the phosphor particles can be larger in the fluorescent layer such as silica gel or resin as the adhesive phase, and the ratio of the adhesive phase and the phosphor can also be adjusted within a larger range, the silicone fluorescent layer or The conversion efficiency of the resin fluorescent layer is higher than that of the fluorescent ceramic or fluorescent glass of the same color.

The phosphor particle size is greater than 0 and less than or equal to 10 microns. The ratio of the fluorescent powder to the silica gel or resin is 1: 1 to 1:10. The thickness of the silica gel fluorescent layer or the resin fluorescent layer 103 is greater than 0 and less than or equal to 50 microns, and the optimal thickness of the silica gel fluorescent layer or the resin fluorescent layer 103 is greater than or equal to 40 microns and less than or equal to 50 microns.

The third wavelength conversion layer 104 is located on the silicone fluorescent layer or the resin fluorescent layer 103. The third wavelength conversion layer 104 is used to convert light emitted from the light emitting diode 101 into light of a third wavelength. The two wavelengths can be the same or different.

The thermal conductivity of the third wavelength conversion layer 104 is greater than that of the silica gel fluorescent layer or the resin fluorescent layer 103, so the heat generated by the silica gel fluorescent layer or the resin fluorescent layer 103 can be diffused through the third wavelength conversion layer 104. It can be understood that, in some embodiments, the first wavelength conversion device and the second wavelength conversion layer are main light emitting areas, and most of the final emitted light is composed of the first wavelength light and the second wavelength light, so the first wavelength conversion Layer and the second wavelength conversion layer generate more heat; especially the second wavelength conversion layer, due to its lower conversion efficiency compared to other wavelength conversion materials, generates more heat; and only a few light-emitting diodes The emitted light is converted into the third wavelength light by the third wavelength conversion layer. Therefore, the heat generated by the third wavelength conversion layer is smaller than that of the second wavelength conversion layer; at the same time, the third wavelength is converted into heat conduction such as fluorescent ceramics or fluorescent glass. A material with a higher coefficient, so that the heat generated by the silica gel fluorescent layer or the resin fluorescent layer 103 can be diffused through the third wavelength conversion layer 104.

The third wavelength conversion layer 104 includes at least one of a fluorescent ceramic or a fluorescent glass, and the structure of the third wavelength conversion layer 104 may be the same as that of the first wavelength conversion layer 102.

The above embodiments are merely illustrative, and do not limit the protection scope of the present application.

FIG. 2 is a schematic structural diagram of a second embodiment of a light emitting diode package structure of the present application.

The main difference between the first embodiment and the second embodiment of the light-emitting diode package structure of the present application is that the second wavelength conversion layer of the first embodiment is a silica gel fluorescent layer or a resin fluorescent layer, and the second wavelength conversion layer of the second embodiment It is a quantum dot film.

As shown in FIG. 2, 201 is a light emitting diode, 202 is a first wavelength conversion layer, 203 is a quantum dot thin film layer, and 204 is a third wavelength conversion layer.

The first wavelength conversion layer 202 is located between the quantum dot thin film layer 203 and the light emitting diode 201. The first wavelength conversion layer 202 is used to convert light emitted from the light emitting diode 201 into light of a first wavelength. The light emitted from the light emitting diode 201 is converted into light of a second wavelength, and the first wavelength is different from the second wavelength.

The thermal conductivity of the first wavelength conversion layer 202 is greater than that of the quantum dot thin film layer 203, so the heat generated by the quantum dot thin film layer 203 can be diffused through the first wavelength conversion layer 202.

The third wavelength conversion layer 204 is located on the quantum dot film 203. The third wavelength conversion layer 204 is used to convert light emitted from the light emitting diode 201 into light of a third wavelength. The third wavelength may be the same as the first wavelength / second wavelength. It can also be different.

The thermal conductivity of the third wavelength conversion layer 204 is greater than that of the quantum dot film 203, so the heat generated by the quantum dot film 203 can be diffused through the third wavelength conversion layer 204.

A quantum dot is a low-dimensional semiconductor material, and its dimensions in three dimensions are not larger than twice the Bohr radius of the exciton of the corresponding semiconductor material. Quantum dots are generally spherical or spheroidal, and their diameter is often between 2 and 20 nanometers. The quantum dots in the quantum dot film 203 may be red light quantum dots, such as cadmium compounds containing cadmium selenide and zinc sulfide, cadmium compounds containing cadmium selenide and zinc cadmium sulfide, and non-cadmium containing copper indium sulfur and zinc sulfide. Compound, and can reduce the blue light absorption rate by adjusting the formula and thickness of the quantum dots.

FIG. 3 is a schematic structural diagram of a third embodiment of a light emitting diode package structure of the present application.

As shown in FIG. 3, 301 is a light emitting diode, 302 is a first wavelength conversion layer, 303 is a silica gel fluorescent layer or a resin fluorescent layer, and 304 is a light guiding layer.

The main difference between the third embodiment and the first embodiment of the light-emitting diode package structure of the present application is that the third embodiment is located on the silicone fluorescent layer or the resin fluorescent layer as the third wavelength conversion layer, and the third embodiment is located on the silicone fluorescent layer. Above the layer or resin fluorescent layer is a light guide layer.

The first wavelength conversion layer 302 is located between the silicone fluorescent layer or the resin fluorescent layer 303 and the light emitting diode 301. The first wavelength conversion layer 302 is used to convert light emitted from the light emitting diode 301 into light of the first wavelength. The fluorescent layer 303 is used to convert light emitted from the light emitting diode 301 into light of a second wavelength, and the first wavelength is different from the second wavelength.

304 light guide layer is located on the silica gel fluorescent layer or resin fluorescent layer 303. The light guide layer 304 can be composed of sapphire. The surface of the light guide layer 304 can be microstructured, or an antireflection coating can be plated to improve the light extraction on the surface. Efficiency (light emitting efficiency). In addition, the light guiding layer 304 can play a role of light guiding, which can greatly improve light emitting efficiency. It can be understood that the light guide layer may also be other transparent ceramic materials, such as yttrium aluminum garnet (Y3Al5O12), magnesium aluminum spinel (MgAl2O4), aluminum nitride (AlN), aluminum nitride (AION) and other transparent ceramic materials; In some other embodiments, the light guide layer may also be glass. Since the light guide layer has a high thermal conductivity and it does not generate heat from wavelength conversion, it can well realize the heat dissipation of the second wavelength conversion layer and improve the thermal stability of the second wavelength conversion layer.

FIG. 4 is a schematic structural diagram of a fourth embodiment of a light emitting diode package structure of the present application.

As shown in FIG. 4, 401 is a light emitting diode, 402 is a first wavelength conversion layer, 403 is a quantum dot film, and 404 is a light guide layer.

The main difference between the fourth embodiment and the second embodiment of the light emitting diode package structure of the present application is that the third embodiment is a third wavelength conversion layer on the quantum dot film, and the fourth embodiment is on the quantum dot film. Is a light guide layer.

The first wavelength conversion layer 402 is located between the quantum dot film 403 and the light emitting diode 401. The first wavelength conversion layer 402 is used to convert light emitted from the light emitting diode 401 into light of a first wavelength, and the quantum dot film 403 is used to convert light emitting diodes. The light emitted by the 401 is converted into light of a second wavelength, and the first wavelength is different from the second wavelength.

The light guide layer 404 is located on the quantum dot thin film layer 403.

FIG. 5 is a schematic structural diagram of a fifth embodiment of a light emitting diode package structure of the present application.

As shown in FIG. 5, 501 is a light emitting diode, 502 is a first wavelength conversion layer, 503 is a silica gel fluorescent layer or a resin fluorescent layer, 504 is a third wavelength conversion layer, and 505 is a light guide layer.

The main difference between the fifth embodiment and the first embodiment of the light-emitting diode package structure of the present application is that the fifth embodiment has one more light guiding layer than the first embodiment.

The first wavelength conversion layer 502 is located between the silica gel fluorescent layer or the resin fluorescent layer 503 and the light emitting diode 501. The first wavelength conversion layer 502 is used to convert light emitted from the light emitting diode 501 into light of the first wavelength. The silica gel fluorescent layer or resin The fluorescent layer 503 is used to convert light emitted from the light emitting diode 501 into light of a second wavelength, and the first wavelength is different from the second wavelength.

The third wavelength conversion layer 504 is located on the silicone fluorescent layer or the resin fluorescent layer 503. The third wavelength conversion layer 504 is used to convert light emitted from the light emitting diode 501 into light of a third wavelength. The two wavelengths can be the same or different.

The light guide layer 505 is located on the third wavelength conversion layer 504.

FIG. 6 is a schematic structural diagram of a sixth embodiment of a light emitting diode package structure of the present application.

As shown in FIG. 6, 601 is a light emitting diode, 602 is a first wavelength conversion layer, 603 is a quantum dot film, 604 is a third wavelength conversion layer, and 605 is a light guide layer.

The main difference between the sixth embodiment and the second embodiment of the light-emitting diode package structure of the present application is that the sixth embodiment has one more light guiding layer than the second embodiment.

The first wavelength conversion layer 602 is located between the quantum dot film 603 and the light emitting diode 601. The first wavelength conversion layer 602 is used to convert light emitted from the light emitting diode 601 into light of a first wavelength, and the quantum dot film 603 is used to convert light emitting diodes. The light emitted by 601 is converted into light of a second wavelength, and the first wavelength is different from the second wavelength.

The third wavelength conversion layer 604 is located on the quantum dot film 603. The third wavelength conversion layer 604 is used to convert light emitted from the light emitting diode 601 into light of a third wavelength. The third wavelength may be the same as the first wavelength / second wavelength. It can also be different.

The light guide layer 605 is located on the third wavelength conversion layer 604.

The present application provides a light emitting diode package structure including a first wavelength conversion layer, a second wavelength conversion layer, and a third optical layer; the first wavelength conversion layer is located between the second wavelength conversion layer and the light emitting diode; A third optical layer is disposed on a side of the two wavelength conversion layer away from the first wavelength conversion layer, and the third optical layer includes a light guide layer and / or a third wavelength conversion layer; wherein the first wavelength conversion layer is configured to emit the light emitting diode. Light is converted into light of a first wavelength, the second wavelength conversion layer is used to convert light emitted by the light emitting diode into light of a second wavelength, the first wavelength is different from the second wavelength, and the third wavelength conversion layer is used to convert the light emitting diode The emitted light is converted into light of a third wavelength. The second wavelength conversion layer includes at least one of a fluorescent ceramic, a fluorescent glass, a silica gel fluorescent layer, a resin fluorescent layer, and a quantum dot film. The light of the second wavelength can make up the missing part of the spectrum and has higher conversion efficiency. To improve the color rendering index of the packaged light emitting diode. At the same time, since the thermal conductivity of the first wavelength conversion layer and the third optical layer is greater than that of the second wavelength conversion layer, the heat generated by the second wavelength conversion layer can be diffused out through the first wavelength conversion layer and the third optical layer, ensuring that Light-emitting diode reliability.

FIG. 7 is a schematic flowchart of an embodiment of a light emitting diode packaging method according to the present application.

S10: A first wavelength conversion layer is provided on the light emitting diode.

The first wavelength conversion layer is used to convert light emitted from the light emitting diode into light of a first wavelength.

The light emitting diode may be a blue light emitting diode, a single light emitting diode, a light emitting diode group formed by a plurality of light emitting diode groups, or other light emitting diodes, which is not specifically limited herein.

At least one of a fluorescent ceramic or a fluorescent glass is disposed on the light emitting diode to form a first wavelength conversion layer. The fluorescent ceramic layer may be a pure phase fluorescent ceramic layer or a multi-phase fluorescent ceramic layer.

The silica gel fluorescent layer includes silica gel and a phosphor, wherein the silica is used as an adhesive phase to encapsulate the phosphor therein. The fluorescent glass layer includes a fluorescent powder and glass, wherein the glass serves as an adhesive phase to encapsulate the fluorescent powder therein. Pure-phase fluorescent ceramic layers are generally composed of pure-phase fluorescent ceramics, excluding other components as a bonding phase; such as cerium-doped yttrium aluminum garnet pure-phase fluorescent ceramics (YAG: Ce). The multi-phase fluorescent ceramic layer includes a phosphor and a ceramic material, wherein the ceramic material is used as an adhesive phase to encapsulate the phosphor therein, such as a common ceramic material such as alumina, undoped yttrium aluminum garnet, etc .; in some specific embodiments, In this case, the fluorescent ceramic can be YAG: Ce & Al2O3, which is a cerium-doped yttrium aluminum garnet phosphor and alumina as a composite phase fluorescent ceramic. It can be understood that the ratio of silica gel and phosphor in the silicone fluorescent layer can be adjusted, the ratio of phosphor and glass powder in the fluorescent glass layer can be adjusted, the ratio of yttrium aluminum garnet and cerium in the pure phase ceramic layer can be adjusted, and the multi-phase fluorescent ceramic layer The ratio of medium yttrium aluminum garnet, cerium and alumina can be adjusted.

The preparation of the fluorescent glass includes: mixing the fluorescent powder, the glass powder and the organic carrier, and then performing dispensing or doctor coating, and then melt-molding to form the fluorescent glass layer. The melting temperature is specifically set according to the selected glass powder and phosphor. Further, the melt molding further includes a step of preparing a release layer, which is specifically as follows: firstly, at least one powder of boron nitride, titanium dioxide, and alumina is mixed with an organic carrier to form a release slurry, and the slurry is coated; A release layer is formed on the ceramic substrate, and then a mixed slurry of phosphor powder, glass powder, and an organic carrier is uniformly knife-coated on the release layer; then melt molding is performed. The ceramic substrate may be at least one of an aluminum nitride substrate and an alumina substrate. The setting of the release layer can facilitate the fluorescent glass to be easily separated from the ceramic substrate after being melt-molded; it is convenient for subsequent operations.

The preparation of the fluorescent ceramic includes: cutting and processing the fluorescent ceramic into a sheet-shaped fluorescent ceramic layer. In some embodiments, the finished fluorescent ceramic is directly cut into fluorescent ceramic layers of a desired thickness and size as required. If necessary, the fluorescent ceramic can be further polished.

The first wavelength conversion layer and the light emitting diode may be bonded together with a colorless and transparent optical adhesive, or may be bonded with silicone.

S11: A second wavelength conversion layer is provided on the first wavelength conversion layer.

The second wavelength conversion layer is used to convert light emitted by the light emitting diode into light of a second wavelength, and the first wavelength is different from the second wavelength. The second wavelength conversion layer includes a silicone fluorescent layer or a resin fluorescent layer, and a quantum dot film. at least one.

Light of the first wavelength, light of the second wavelength, and light not emitted by the light emitting diode may be mixed to obtain white light. In general, white light can also be obtained by mixing light of the first wavelength with light that is emitted by the LED and is not absorbed. Compared with the two types of white light, the former adds light of the second wavelength, which can supplement the missing part of the spectrum, thereby improving the color rendering index. For example, the light emitted by the light emitting diode is blue light, the light of the first wavelength may be yellow, and the light of the second wavelength may be red.

The silica gel and the phosphor are mixed to form a silica gel phosphor layer, and the resin and the phosphor are mixed to form a resin phosphor layer, wherein the phosphor includes at least one of a cyan phosphor, a green phosphor, and a red phosphor. The red phosphor may be a red nitride phosphor such as (Sr, Ca) AlSiN3: Eu2 +. The conversion efficiency of the silicone fluorescent layer or the resin fluorescent layer is higher than that of the fluorescent ceramic or fluorescent glass of the same color.

The particle diameter of the phosphor is greater than 0 and less than or equal to 10 microns; the ratio of the phosphor to the binder is from 1: 1 to 1:10; the thickness of the silica gel or resin phosphor layer is greater than 0 and less than or equal to 50 microns.

The manufacturing process of silica gel fluorescent layer or resin phosphor layer is to mix silica gel, resin and phosphor uniformly, then place it in a vacuum environment to remove air bubbles, and apply it on polyterephthalic acid plastic with no adhesion enhancement on the surface Then, it is baked at 150 degrees Celsius for 5 to 10 minutes to perform a mold release treatment, and then baked to completely cure the coating. It can be understood that, in other embodiments, according to the specific type of the silica gel or the resin, a curing method such as photocuring may also be adopted.

The thermal conductivity of the first wavelength conversion layer is greater than that of the second wavelength conversion layer, so the heat generated by the second wavelength conversion layer can be diffused through the first wavelength conversion layer.

S12: A third optical layer is disposed on a side of the second wavelength conversion layer away from the first wavelength conversion layer. The third optical layer includes a light guide layer and / or a third wavelength conversion layer.

Only a third wavelength conversion layer may be provided on the second wavelength conversion layer, or a third wavelength conversion layer may be provided on the second wavelength conversion layer and a light guide layer may be provided on the third wavelength conversion layer. The light guide layer may be composed of sapphire . The third wavelength conversion layer is used to convert light emitted from the light emitting diode into light of a third wavelength, and the third wavelength may be the same as or different from the first wavelength / the second wavelength.

The thermal conductivity of the third wavelength conversion layer is greater than that of the second wavelength conversion layer.

The method for preparing the third wavelength conversion layer may be the same as the first wavelength conversion layer, and the structure of the third wavelength conversion layer may be the same as the first wavelength conversion layer.

The first wavelength conversion layer and the second wavelength conversion layer may be bonded together with a colorless transparent optical adhesive, or may be bonded using silica gel. Similarly, the second wavelength conversion layer, the third wavelength conversion layer, and the third wavelength conversion layer The second wavelength conversion layer, the light guide layer and the second wavelength conversion layer, and the third wavelength conversion layer and the light guide layer may be bonded with a colorless transparent optical glue or silicone.

FIG. 8 is a schematic flowchart of another embodiment of a light emitting diode packaging method of the present application.

S20: providing a first wavelength conversion layer on the light emitting diode, a second wavelength conversion layer on the first wavelength conversion layer, and a third optical layer on a side of the second wavelength conversion layer away from the first wavelength conversion layer, The third optical layer includes a light guide layer and / or a third wavelength conversion layer.

S21: The three-layer structure is attached to the light emitting diode, and the first wavelength conversion layer is close to the light emitting diode.

It can be understood that, in some other implementation manners, the order of operation steps of an embodiment of the light emitting diode packaging method of the present application can be appropriately adjusted as needed. Exemplarily, the bonding method may also be that the at least one of the first wavelength conversion layer, the second wavelength conversion layer, the third wavelength conversion layer, and the light guide layer is sequentially bonded and then cut into the same size as the light emitting diode. The block is then attached to the light-emitting diode. Similarly, a colorless transparent optical glue or silicone can be used.

FIG. 9 is a schematic view showing the effect of a prior art packaging scheme for light emitting diodes, in which the wavelength conversion layer uses a silicone-encapsulated phosphor, that is, a silicone phosphor layer. As shown in FIG. Uniformity of light output. Because the final light emitted from the light emitting surface includes the light from the unconverted LED chip, the light from the first wavelength conversion layer, and the light from the second wavelength conversion layer (in this case, the Light emitted), the above three different sources of light are sufficiently uniformly mixed to obtain uniform color and brightness of the emitted light, and the light exit surface with poor surface flatness makes the optical path of light at different positions different, so the light at different positions is uniform Sex is affected.

FIG. 10 is a schematic view showing an effect of an embodiment of a packaging scheme for a light emitting diode of the present application, wherein a third wavelength conversion layer is provided on the second wavelength conversion layer, and in this embodiment, the third wavelength conversion layer is made of The flatness of the light emitting surface of the cerium fluorescent ceramic layer and the third wavelength conversion layer is higher than that of the silica gel fluorescent layer in FIG. 9, which improves the light uniformity of the packaging structure described in this application. At the same time, on the one hand, as described above, the use of a third wavelength conversion layer with high thermal conductivity such as fluorescent ceramics can improve the heat dissipation of the second wavelength conversion layer, and on the other hand, the third wavelength conversion layer blocks the second wavelength conversion The direct contact between the layer and the external environment (such as air) can avoid the degradation and failure of the second wavelength conversion layer at a higher temperature. In particular, in the embodiment in which the second wavelength conversion layer uses a silicone, a resin, or the like to encapsulate red phosphor, .

The present application provides a method for packaging a light emitting diode, which includes sequentially laminating a first wavelength conversion layer, a second wavelength conversion layer, and a third optical layer on the light emitting diode; or, laminating sequentially The first wavelength conversion layer, the second wavelength conversion layer, and the third optical layer are stacked, and then they are bonded and disposed on the light emitting diode, and the first wavelength conversion layer is close to the light emitting diode; Color transparent optical adhesive bonding; the third optical layer includes a light guide layer and / or a third wavelength conversion layer; the first wavelength conversion layer and the third wavelength conversion layer include at least one of a fluorescent ceramic or a fluorescent glass; a light guide layer The second wavelength conversion layer includes at least one of a fluorescent ceramic, a fluorescent glass, a silica gel fluorescent layer, a resin fluorescent layer, and a quantum dot film. . The light of the second wavelength emitted by the second wavelength conversion layer can make up for the missing part of the spectrum and has higher conversion efficiency, and improves the color rendering index of the light-emitting diode after packaging. At the same time, since the thermal conductivity of the first wavelength conversion layer and the third optical layer is greater than that of the second wavelength conversion layer, the heat generated by the second wavelength conversion layer can be diffused out through the first wavelength conversion layer and the third optical layer, ensuring that Light-emitting diode reliability.

Again, the above description is only an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the description of the application and the contents of the drawings, such as the technology between the embodiments The mutual combination of features, or direct or indirect use in other related technical fields, is similarly included in the scope of patent protection of this application.

Claims

A light emitting diode packaging structure, characterized in that the packaging structure includes a first wavelength conversion layer, a second wavelength conversion layer, and a third optical layer;

The first wavelength conversion layer is located between the second wavelength conversion layer and the light emitting diode; the third optical layer is provided on a side of the second wavelength conversion layer remote from the first wavelength conversion layer, The third optical layer includes a light guide layer and / or a third wavelength conversion layer;

The first wavelength conversion layer is configured to convert light emitted by the light emitting diode to light of a first wavelength, and the second wavelength conversion layer is configured to convert light emitted by the light emitting diode to a second wavelength Light, the first wavelength is different from the second wavelength, and the third wavelength conversion layer is configured to convert light emitted by the light emitting diode into light of a third wavelength.
The package structure according to claim 1, wherein a thermal conductivity of the first wavelength conversion layer and / or the third optical layer is greater than a thermal conductivity of the second wavelength conversion layer.
The package structure according to claim 1, wherein the first wavelength conversion layer and / or the third wavelength conversion layer is at least one of a fluorescent ceramic or a fluorescent glass.
The package structure according to claim 1, wherein the second wavelength conversion layer is at least one of a fluorescent ceramic, a fluorescent glass, a silica gel fluorescent layer, a resin fluorescent layer, and a quantum dot film.
The package structure according to claim 4, wherein a particle diameter of the phosphor in the resin fluorescent layer and / or the silica gel fluorescent layer is greater than 0 and less than or equal to 10 microns.
The package structure according to claim 4, wherein the thickness of the silica gel fluorescent layer and / or the resin fluorescent layer is greater than 0 and less than or equal to 50 microns.
The package structure according to claim 4, wherein a ratio of the phosphor to the resin or the silica gel in the resin fluorescent layer and / or the silica gel fluorescent layer is 1: 1 to 1:10.
The package structure according to claim 1, wherein the first wavelength is smaller than the second wavelength.
A light emitting diode packaging method, characterized in that the method includes:

The first wavelength conversion layer, the second wavelength conversion layer, and the third optical layer are sequentially laminated on the light emitting diode; or, the first wavelength conversion layer and the second wavelength are sequentially laminated on the light emitting diode. A conversion layer and the third optical layer, which are then attached to the light emitting diode, and the first wavelength conversion layer is close to the light emitting diode;

The bonding method uses colorless and transparent optical adhesive bonding;

The third optical layer includes a light guide layer and / or a third wavelength conversion layer;

The first wavelength conversion layer and the third wavelength conversion layer include at least one of a fluorescent ceramic or a fluorescent glass;

The light guide layer includes at least one of transparent ceramic or glass;

The second wavelength conversion layer includes at least one of a fluorescent ceramic, a fluorescent glass, a silica gel fluorescent layer, a resin fluorescent layer, and a quantum dot film.
The packaging method according to claim 9, further comprising at least one of the following steps:

The preparation of the silica gel fluorescent layer or the resin fluorescent layer includes: mixing the silica gel or the resin with a phosphor, performing dispensing or doctor coating, and then curing to form the silica gel fluorescent layer or the resin fluorescent layer;

The preparation of the fluorescent glass includes: mixing fluorescent powder, glass powder, and an organic carrier, and then performing dispensing or doctor coating, and then melt-molding to form the fluorescent glass;

The preparation of the fluorescent ceramic includes: cutting and processing the fluorescent ceramic into a thin sheet of the fluorescent ceramic.