TWM594809U - Light-emitting diode element and luminaire for plant lighting - Google Patents

Abstract

A light-emitting diode element for plant lighting is provided. The light-emitting diode element comprises: a blue light-emitting diode chip; an encapsulation material layer, which covers the blue light-emitting diode chip; and first phosphor powders dispersed in the encapsulation material layer and can be excited the blue light-emitting diode chip with an emission peak wavelength in the range of 650-655 nm and a full width at half maximum of less than 55 nm.

Description

Light-emitting diode components and lamps for plant lighting

This creation relates to a light-emitting diode (LED) element, in particular to a light-emitting diode element for plant lighting, and a lamp including the light-emitting diode element.

In the 19th century, the Russian botanist Andrei Famintsyn tried to use artificial light sources in plant research, opening up various studies and applications of various light sources on plant growth and related chemical reactions. try. The research not only realized the change of plant growth mode and cycle, but also allowed plants to be mass-produced by artificial methods without being restricted by natural conditions. With the evolution of technology, the light source of plant lighting has also evolved from incandescent lamps and fluorescent lamps to the currently used high intensity discharge (HID) lamps. In addition, the luminous power of the luminaire has been significantly improved with continuous research, and the emitted spectrum has evolved from full spectrum to tunable spectrum. The above changes make the plant lighting system gradually replace sunlight as the protagonist from the role of early auxiliary sunlight, and can begin to supplement the specific spectrum required by plants.

In recent years, benefiting from the development of the semiconductor industry, light-emitting diode light sources (also referred to herein as "LED light sources") provide another option for plant lighting. The LED light source not only has the advantages of low energy consumption and many types of colored light, but also the full width at half maximum (fwhm) of each colored light is narrower than the traditional light source, which allows the LED light source to meet the needs of plants The absorption spectra are more easily combined to achieve the effective use of the light source. For example, Figure 1 shows the absorption spectra of chlorophyll a and chlorophyll b necessary for photosynthesis in plants, and the emission spectra of red and blue LEDs. As shown in FIG. 1, the core regions of the absorption spectrum of chlorophyll a and chlorophyll b are the blue absorption region near 450 nm and the red absorption region near 650 nm. Therefore, the blue LED can provide the blue wavelength band required for the photosynthesis of chlorophyll a and chlorophyll b, and has the effects of promoting the growth of plant leaves, protein synthesis and fruit formation, and the red LED can provide the photosynthesis of chlorophyll a and chlorophyll b. The required red light band has the effects of promoting plant stem growth, carbohydrate synthesis and flowering. Therefore, the combination of blue LED light source and red LED light source is used to provide plant lighting. Compared with traditional full-spectrum light sources (such as incandescent lamps), it not only saves many spectral bands that are unnecessary for chlorophyll, but also reduces lamps. The energy consumption and heat dissipation burden.

However, the combination of LED light sources with different light colors has several shortcomings, including: LED light sources with different light colors need to be matched with a specific arrangement to achieve a uniform light mixing effect, which is not only difficult to mix but also needs to be relatively complicated Circuit layout; different light attenuation levels, different light color LED light sources have different lifespans and light attenuation levels, and color light ratio errors are prone to occur after long-term use; and the monochromatic LED light source has a narrow peak width and is not easy to move, which is not conducive to broad peaks Spectral combination.

In response to the above problems, a light-emitting diode element (also referred to as "LED element") composed of a monochromatic LED light source and a specific phosphor is a feasible technical means, in which a layer containing phosphor is provided On a monochromatic LED light source, the monochromatic LED light source is used to excite the unique emission spectrum of phosphor powder, so that the light emitted by the phosphor powder is mixed with the LED light passing through the phosphor powder layer to achieve a spectral combination and The effect of uniform light mixing. For example, CN 104465963 B discloses an LED device using CaAlSiN ₃ :Eu (also referred to herein as “CASN”) red phosphor and blue LED light source. However, as shown in Figure 2, the red light emitted by the CASN red phosphors can cover the red light band required for photosynthesis of chlorophyll a and chlorophyll b, but its half-height width is too large, which emits a lot of chlorophyll. Useless energy, especially near infrared light in excess of 700 nanometers. In addition, other commonly used oxide, fluoride or nitride red phosphors also have the problem of half-width and over-width, or the problem of the peak position being blue or red.

In view of the foregoing technical problems, the present invention provides a light-emitting diode device in which a blue light-emitting diode chip and a red phosphor that can be excited by blue light to emit a specific spectrum are used. The emission spectrum of the light-emitting diode element of this creation can fully correspond to the blue and red bands required for photosynthesis of chlorophyll a and chlorophyll b, which can provide efficient plant lighting and greatly reduce energy waste.

Therefore, one of the purposes of this creation is to provide a light-emitting diode element for plant lighting, which includes: a blue light-emitting diode chip; a packaging material layer covering the blue light-emitting diode chip; and a first fluorescent light The powder is dispersed in the encapsulation material layer and can be excited by the light emitted by the blue light-emitting diode chip, emitting light with a peak between 650 nm and 655 nm and a half-height width of less than 55 nm.

In some implementations of this creation, the first phosphor is SrLiAl ₃ N ₄ : Eu ²⁺ phosphor, and the SrLiAl ₃ N ₄ : Eu ²⁺ phosphor is preferably a barium-containing nitride In the presence, it is prepared by hot isostatic pressing (hot isostatic pressing) method, in which the barium-containing nitride may be Ba ₃ N ₂ .

In some implementations of this creation, the above hot isostatic pressing sintering method is performed in an inert atmosphere at a temperature of 800°C to 1500°C and a pressure of 10MPa to 200MPa.

In some implementations of this creation, the surface of the particles of the first phosphor can be treated with surface coating.

In some implementations of this creation, the light-emitting diode element further includes a second phosphor, which is different from the first phosphor and is dispersed in the encapsulating material layer, and is selected from the following Group: green phosphor, orange phosphor, infrared phosphor, and combinations thereof.

In some implementations of this creation, the surface of the particles of the second phosphor can be treated with surface coating.

In some implementations of this creation, the blue light-emitting diode chip emits light with a peak between 440 nm and 480 nm.

Another purpose of this creation is to provide a luminaire for plant lighting that includes the light-emitting diode elements as described above.

In order to make the above purpose, technical features and advantages of this creation more obvious and understandable, the following is a detailed description with some specific implementations.

400: LED element

401: Bearing base

401a: Circuit

401b: electrode endpoint

402: Blue light emitting diode chip

403a: the first phosphor

403b: Surface coating

404: encapsulation material layer

405: Wire

FIG. 1 is a graph comparing the absorption spectra of chlorophyll a and chlorophyll b with the emission spectra of conventional red and blue LEDs.

FIG. 2 is a comparison chart of the absorption spectra of chlorophyll a and chlorophyll b and the emission spectra of red LED, blue LED, and CaAlSiN ₃ :Eu(CASN) phosphor.

Figure 3 compares the absorption spectra of chlorophyll a and chlorophyll b with the emission spectra of red LED, blue LED, CaAlSiN ₃ :Eu(CASN) phosphor, and SrLiAl ₃ N ₄ :Eu ²⁺ (SLA) phosphor Figure.

FIG. 4 is a schematic diagram of one embodiment of the light-emitting diode device of this creation.

FIG. 5 is a schematic diagram of another embodiment of the light-emitting diode device of this creation.

Fig. 6 is an emission spectrum of one embodiment of the light-emitting diode element of this creation.

FIG. 7 is an emission spectrum of another embodiment of the light-emitting diode element of this creation.

The following will specifically describe some specific implementations based on this creation; however, without departing from the spirit of this creation, this creation can still be practiced in many different forms, and the scope of protection of this creation should not be interpreted as being limited to the specification The specific implementation form stated.

Unless otherwise stated, the terms "a", "the" and similar terms used in this specification and the scope of patent application shall be understood to include both singular and plural forms.

Unless otherwise stated, the terms "first", "second" and similar terms used in this specification and the scope of patent application are only used to distinguish the described elements or components, and have no special meaning in themselves, and are not intended Refers to the order of precedence.

The effect of this creation compared with the prior art is that the blue light emitting diode chip and the red phosphor that can be excited by blue light and emit a specific spectrum are used to prepare the light emitting diode element, so that the light emitting diode element of this creation is released The emission spectrum can fully correspond to the blue and red light bands required for chlorophyll a and chlorophyll b photosynthesis, can provide efficient plant lighting, and can significantly reduce energy waste.

Specifically, the light-emitting diode device of the present invention includes a blue light-emitting diode chip, a packaging material layer, a first phosphor, and an optional second phosphor, as described below.

1.1. Blue light emitting diode chip

The blue light emitting diode chip may be any light emitting diode chip that can emit blue light. Specifically, it may be any light-emitting diode chip that can emit light with a wavelength range of 400 nm to 500 nm and a peak of 430 nm to 450 nm. For example, the wavelength range may be from 410 nm to 500 nm, 420 nm to 500 nm, 430 nm to 500 nm, 440 nm to 500 nm, 450 nm to 500 nm, 460 nm to 500 nm, 470 nm to 500 nm, 480 nm to 500 nm, 490 nm to 500 nm, or any two of the above The range of values. The peak can be 435 nm, 440 nm, or 445 nm.

Examples of blue light-emitting diode chips include, but are not limited to, GaN-based light-emitting diode chips, InGaN-based light-emitting diode chips, InAlGaN-based light-emitting diode chips, SiC-based light-emitting diode chips, ZnSe-based light-emitting diodes A wafer, a BN-based light-emitting diode wafer, and a BAlGaN-based light-emitting diode wafer.

1.2. Packaging material layer

In the light-emitting diode device of this creation, the packaging material layer covers the blue light-emitting diode chip to provide the packaging function, and its material is not particularly limited, which can be derived from any optical packaging known in the technical field of the creation Materials used include, but are not limited to, epoxy resin, silicone, etc.

1.3. First phosphor

The first phosphor is dispersed in the packaging material layer and can be excited by the light emitted by the blue light-emitting diode chip, thereby emitting light with a peak between 650 nm and 655 nm and a half-height width of less than 55 nm . For example, the first phosphor can emit peaks between 650.5 nm to 655 nm, 651 nm to 655 nm, 651.5 nm to 655 nm, 652 nm to 655 nm, 652.5 nm to 655 nm Light from the range of 653 nanometers to 655 nanometers, 653.5 nanometers to 655 nanometers, 654 nanometers to 655 nanometers, 654.5 nanometers to 655 nanometers, or any two of the above endpoints, and The emitted light has 45 nm to 54.5 nm, 45.5 nm to 54 nm, 46 nm to 53.5 nm, 46.5 nm to 53 nm, 47 nm to 52.5 nm, 47.5 nm to 52 nm Rice, 48 nanometers to 51.5 nanometers, 48.5 nanometers to 51 nanometers, 49 nanometers to 50.5 nanometers, 49.5 nanometers to 50 nanometers, or the half-height width of the range formed by any two of the above endpoints.

In some implementations of the light-emitting diode element created in this work, the first phosphor is SrLiAl ₃ N ₄ : Eu ²⁺ phosphor, where Eu ²⁺ is an activator, and its content is not particularly limited. Those with ordinary knowledge in the technical field to which the creation belongs may adjust as needed. Generally speaking, based on the total content of Sr and Eu ²⁺ in 1 mol, the content of Eu ²⁺ may be 0.01 mol to 0.2 mol. Further, SrLiAl ₃ N _4: Eu ²⁺ phosphor powder is preferably based on the existence of a barium-containing nitride, hot isostatic pressing sintering method to obtain the SrLiAl ₃ N _4: Eu ²⁺ phosphor. Examples of the barium-containing nitride include, but are not limited to, Ba ₃ N ₂ , which can provide a fluxing effect to produce micron-level large-particle phosphors. The hot isostatic pressing sintering method is generally carried out in an inert atmosphere at a temperature of 800° C. to 1500° C. and a pressure of 10 MPa to 200 MPa. For metals containing metal elements constituting SrLiAl ₃ N ₄ :Eu ²⁺ phosphor powder The nitride is hot isostatically sintered to form SrLiAl ₃ N ₄ :Eu ²⁺ phosphor powder. For specific implementation, reference may be made to the examples in the following examples.

The primary particle size distribution of SrLiAl ₃ N ₄ :Eu ²⁺ phosphor prepared by the above hot isostatic pressing sintering method can reach a particle size of 25 microns to 50 microns, such as 26 microns, 27 microns, 28 microns , 29 microns, 30 microns, 31 microns, 32 microns, 33 microns, 34 microns, 35 microns, 36 microns, 37 microns, 38 microns, 39 microns, 40 microns, 41 microns, 42 microns, 43 microns, 44 microns, 45 Micrometer, 46 micrometer, 47 micrometer, 48 micrometer, or 49 micrometer, has more excellent light emitting efficiency, heat resistance and low thermal decay properties, making the light-emitting diode element of this creation more suitable for long-term plant lighting, can Maintain and promote photosynthesis of plants with high performance and low cost.

Figure 3 compares the absorption spectra of chlorophyll a and chlorophyll b with the emission spectra of red LED, blue LED, CaAlSiN ₃ : Eu (CASN) red phosphor and SrLiAl ₃ N ₄ : Eu ²⁺ (SLA) phosphor Figure. As shown in Fig. 3, the emission spectrum of SLA phosphors can not only cover the red light band required by chlorophyll a and chlorophyll b, but also reduce the amount of chlorophyll a and chlorophyll b that are not required compared to CASN red phosphors by 10%. The amount of photon emission greatly reduces the energy waste problem.

1.3. The second phosphor as needed

In the light-emitting diode device of the present invention, in addition to the first phosphor, a second phosphor that can be excited by blue light and emit light may be further included as needed. The second phosphor is different from the first phosphor and is also dispersed in the packaging material layer. Examples of the second phosphor include, but are not limited to, selected from the group consisting of green phosphor, orange phosphor, infrared phosphor, and combinations thereof. In some implementations of this creation, green fluorescent powder is used as the second fluorescent powder. The green light emitted by the green fluorescent powder can also promote the growth of some plants. When the second fluorescent powder is an infrared fluorescent powder that is excited by blue light and emits infrared light, it can stimulate the extension of the stem of the plant.

1.4. Composition of light-emitting diode components

In the following, with reference to the accompanying drawings, examples of the specific implementation of the light-emitting diode element of this creation are illustrated, but this creation is not limited to this.

FIG. 4 is a schematic diagram of one embodiment of the light-emitting diode device of this creation. As shown in FIG. 4, the light emitting diode device 400 includes a supporting base 401, a circuit 401 a, an electrode terminal 401 b, a blue light emitting diode chip 402, a first phosphor 403 a, a packaging material layer 404, and a wire 405 Wherein, the carrying base 401 is used to carry the blue light-emitting diode chip 402, the packaging material layer 404 covers the blue light-emitting diode chip 402, and the first phosphor 403a is dispersed in the packaging material layer 404.

The mixing ratio of the encapsulating material layer 404 and the first phosphor 403a will affect the ratio of blue light to red light emitted by the light emitting diode element, and increasing the content of the first phosphor powder 403a will increase the amount of light emitted by the light emitting diode element The total amount of red light relatively reduces the total amount of blue light emitted by the light-emitting diode element. In the light emitting diode device of the present invention, the weight of the encapsulating material layer 404 to the first phosphor 403a is preferably 1:0.05 to 1:0.5, for example, 1:0.06, 1:0.07, 1:0.08, 1: 0.09, 1:0.1, 1:0.11, 1:0.12, 1:0.13, 1:0.14, 1:0.15, 1:0.16, 1:0.17, 1:0.18, 1:0.19, 1:0.2, 1:0.21 1: 0.22, 1: 0.23, 1:0.24, 1:0.25, 1:0.26, 1:0.27, 1:0.28, 1:0.29, 1:0.3, 1:0.31, 1:0.32, 1:0.33, 1:0.34, 1:0.35, 1: 0.36, 1:0.37, 1:0.38, 1:0.39, 1:0.4, 1:0.41, 1:0.42, 1:0.43, 1:0.44, 1:0.45, 1:0.46, 1:0.47, 1:0.48, Or 1: 0.49.

According to the light-emitting diode device of the present invention, the surfaces of the first phosphor powder and the second phosphor particles as needed may be further subjected to surface plating treatment to provide the desired improved performance. For example, FIG. 5 is a schematic diagram of another embodiment of the light-emitting diode device of the present invention, in which the surface of the first phosphor 403a is treated with a surface coating to have a surface coating 403b, and the surface coating 403b is used to improve water resistance 1. Prevent the phosphor powder from agglomerating, or isolate the phosphor powder to avoid undesirable chemical reactions. The surface plating layer is preferably transparent, and any organic plating material or inorganic plating material known in the technical field to which this creation belongs can be used. Examples of organic plating materials include, but are not limited to, silicone polymers, poly(methyl methacrylate) (PMMA), and polycarbonate (PC). Examples of inorganic plating materials include but are not limited to glass. For the method of performing the surface plating treatment on the surface of the phosphor particles, the surface plating treatment method known in the technical field to which this creation belongs can be used. For example, the surface coating layer can be covered on the surface of the particles of the first phosphor by sol-gel method, chemical vapor deposition method, physical vapor deposition method, or solution adsorption method, but the creation is not limited to this.

2. Lamps for plant lighting

The light-emitting diode element of the present invention can be used for plant lighting. Therefore, the present invention also provides a lamp for plant lighting, which uses the light-emitting diode element of the present invention as a light source.

The following specific examples of implementation are used to further illustrate this creation.

3. Examples

3.1. SrLiAl ₃ N ₄ : Eu ²⁺ Preparation of phosphor

Weigh barium nitride (Ba ₃ N ₂ ), strontium nitride, lithium nitride, aluminum nitride and europium nitride, where the molar ratio of Ba: Sr: Li: Al: Eu is 0.1: 0.98: 1: 3: 0.02, and grind in a boron nitride mortar for 30 minutes. Next, in a hot isostatic pressure sintering furnace (model: AIP6-30H), sintering was carried out in a nitrogen atmosphere at a temperature of 1000°C and a pressure of 100 MPa for four hours. Finally, the obtained product was ground in a mortar to obtain SrLiAl ₃ N ₄ :Eu ²⁺ phosphor. SrLiAl ₃ N ₄ : The primary particle size distribution of Eu ²⁺ phosphor powder ranges from 5 microns to 50 microns, and the average particle diameter is from 10 microns to 15 microns.

3.2. Preparation of light-emitting diode elements

[Example 1]

The blue light-emitting diode chip (the wavelength range of blue light is between 410 nanometers and 480 nanometers and the peak is 440 nanometers) is arranged on a rectangular supporting base, and is connected to wires, circuits and electrode terminals, such as Figure 4 illustrates this.

The liquid silicone resin was mixed with the SrLiAl ₃ N ₄ :Eu ²⁺ phosphor powder in a weight ratio of 1:0.2 to prepare a colloidal mixture with a total weight of 10 g. Next, the colloidal mixture was placed in a vacuum defoaming mixer, and mixed and defoamed. Subsequently, the defoamed colloidal mixture is put into a dispenser, and the colloidal mixture is covered on the blue light-emitting diode wafer by dispensing. After that, the blue light-emitting diode wafer covered with the colloidal mixture was placed in an oven and baked at 120°C for 8 hours to harden the colloidal mixture to obtain a light-emitting diode element.

The light-emitting diode element was placed on the stage of the spectrometer (instrument model: FluoroMax-3, manufactured by HORIBA) and energized to measure the emission spectrum. The emission spectrum of the light-emitting diode element of Example 1 is shown in FIG. 6.

[Example 2]

A light-emitting diode element was prepared in the same manner as in Example 1, except that the weight ratio of liquid silicone resin to SrLiAl ₃ N ₄ :Eu ²⁺ phosphor was adjusted to 1:0.13. The emission spectrum of the light-emitting diode element of Example 2 is shown in FIG. 7.

As shown in FIG. 6, the light emitted by the light-emitting diode device of Example 1 includes blue light with a peak of 440 nm and red light with a peak of 652 nm and a half-height width of 50 nm. The intensity is greater than the intensity of blue light. This shows that the wavelength band of the light emitted by the light-emitting diode element of the present invention can cover and match the absorption spectra of chlorophyll a and chlorophyll b, so it is particularly suitable for promoting and maintaining the photosynthesis of plants.

In addition, as shown in FIG. 7, the light emitted from the light-emitting diode device of Example 2 includes blue light with a peak of 440 nm and red light with a peak of 652 nm and a half-height width of 50 nm. The intensity of light is less than the intensity of blue light. This shows that the intensity of blue light and red light can be changed by adjusting the weight ratio of silicone resin to SrLiAl ₃ N ₄ :Eu ²⁺ phosphor, so those with ordinary knowledge in the technical field of this creation can adjust it according to actual needs The weight ratio of silicone resin to SrLiAl ₃ N ₄ :Eu ²⁺ phosphor powder to obtain the required light-emitting diode components.

The above-mentioned embodiments are merely illustrative for explaining the principle and effect of the creation, and explaining the technical features of the creation, rather than limiting the protection scope of the creation. Anyone who is familiar with this technology can easily complete the changes or arrangements without violating the technical principles and spirit of this creation, which is within the scope of this creation. Therefore, the protection scope of the rights of this creation is as listed in the appended patent application scope.

400: LED element

401: Bearing base

401a: Circuit

401b: electrode endpoint

402: Blue light emitting diode chip

403a: the first phosphor

404: encapsulation material layer

405: Wire

Claims (10)

A light-emitting diode element for plant lighting, including: Blue light emitting diode chip; A layer of encapsulating material covering the blue light-emitting diode chip; and The first phosphor is dispersed in the encapsulation material layer and can be excited by the light emitted by the blue light-emitting diode chip, the emission peak is between 650 nm and 655 nm, and the half-height width is less than 55 nm Light. The light emitting diode element according to claim 1, wherein the first phosphor is SrLiAl ₃ N ₄ :Eu ²⁺ phosphor. The light-emitting diode element according to claim 2, wherein the SrLiAl ₃ N ₄ :Eu ²⁺ phosphor powder is prepared by hot isostatic pressing in the presence of barium-containing nitride. The light-emitting diode element according to claim 3, wherein the barium-containing nitride is Ba ₃ N ₂ . The light emitting diode element of the requested item 3, wherein the hot isostatic sintering method based in an inert atmosphere, at a temperature of 800 ^o C to 1500 ^o C and the pressure of 10 MPa to 200 MPa. The light-emitting diode element according to any one of claims 1 to 5, wherein the particle surface of the first phosphor is subjected to surface plating treatment. The light-emitting diode element according to any one of claims 1 to 5, further comprising a second phosphor, the second phosphor is different from the first phosphor and is dispersed in the packaging material layer, and is It is selected from the group consisting of green phosphor, orange phosphor, infrared phosphor, and combinations thereof. The light-emitting diode element according to claim 7, wherein the particle surface of the second phosphor is subjected to surface plating treatment. The light-emitting diode element according to claim 1, wherein the blue light-emitting diode chip emits light having a peak between 440 nm and 480 nm. A luminaire for plant lighting comprising the light-emitting diode element according to any one of claims 1 to 9.

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