JP2019186305A - Light-emitting device and manufacturing method - Google Patents

Abstract

To achieve a light-emitting device capable of suppressing reduction in quantum efficiency of a semiconductor nanoparticle phosphor caused by heat.SOLUTION: An LED package (1) comprises a phosphor element (10), an LED (51) and an encapsulation material (2). The phosphor element (10) is unevenly distributed on an emission side of fluorescent light in the encapsulation material (2).SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a light emitting device including a nanoparticle phosphor element.

  Semiconductor nanoparticle phosphors have been studied for their application as phosphors. When the semiconductor nanoparticle phosphor is used as a phosphor element, the semiconductor nanoparticle phosphor is dispersed in a matrix and enclosed in an enclosure. Patent Document 1 discloses primary particles (phosphor elements) including a group of semiconductor nanoparticles. The primary particles are individually provided with a layer of surface coating material.

Special table 2013-505347 gazette (released on February 14, 2013)

  The semiconductor nanoparticle fluorescent material has its quantum efficiency (QY) lowered by being given heat. This phenomenon is considered to be caused by the fact that the organic modifying group on the surface of the semiconductor nanoparticle phosphor is removed by heat and a dangling bond is generated on the surface of the nanoparticle phosphor.

  However, Patent Document 1 does not disclose a method for dealing with the phenomenon.

  An object of one embodiment of the present disclosure is to realize a light-emitting device that can suppress a decrease in quantum efficiency of a semiconductor nanoparticle phosphor due to heat.

  In order to solve the above problems, a light-emitting device according to one embodiment of the present disclosure includes a phosphor element including a semiconductor nanoparticle phosphor dispersed in a matrix, a light source that emits excitation light, the phosphor element, and A sealing material that seals the light source, and a side of the sealing material from which the fluorescence emitted by the phosphor element is emitted is referred to as an emission side, and the phosphor element emits the emission from the sealing material. The configuration is unevenly distributed to the side.

  A manufacturing method according to an aspect of the present disclosure includes a phosphor element including a semiconductor nanoparticle phosphor dispersed in a matrix, a light source that emits excitation light, and the phosphor element and a sealing material that seals the light source A first injection step of injecting a first sealing material not including the phosphor element around the light source, and a layer formed by the first injection step. And a second injection step of injecting a second sealing material containing the phosphor element.

  According to one aspect of the present disclosure, it is possible to suppress a decrease in quantum efficiency of the semiconductor nanoparticle phosphor due to heat.

1 is a cross-sectional view illustrating a configuration of an LED package according to Embodiment 1. FIG. It is sectional drawing which shows the structure of a phosphor element. 6 is a cross-sectional view illustrating a configuration of an LED package according to Embodiment 2. FIG. 6 is a cross-sectional view illustrating a configuration of an LED package according to Embodiment 3. FIG. FIG. 6 is a cross-sectional view illustrating a configuration of an LED package according to Embodiment 4. FIG. 6 is a cross-sectional view illustrating a configuration of an LED package according to Embodiment 5. FIG. 10 is a cross-sectional view illustrating a configuration of a phosphor element according to Embodiment 6. It is sectional drawing which shows the structure of the phosphor element which concerns on Embodiment 7. It is sectional drawing which shows multiple types of LED package used in the Example. It is a figure which shows the result of the lighting test of an LED package.

Embodiment 1
Hereinafter, an embodiment of the present disclosure will be described in detail. FIG. 1 is a cross-sectional view illustrating a configuration of an LED (Light Emitting Diode) package 1 (light emitting device) according to the first embodiment. As shown in FIG. 1, the LED package 1 includes an LED 51 (light source), a reflector 52, a sealing material 2, and a phosphor element 10. In the LED package 1, the phosphor element 10 dispersed in the sealing material 2 is directly injected and sealed in the recess 5 of the reflector 52.

  The reflector 52 is a member that reflects the fluorescence emitted from the phosphor element 10 (and part of the excitation light emitted from the LED 51), and the inner surface of the recess 5 functions as a reflecting mirror. The LED 51 is disposed on the bottom surface 52 </ b> A of the recess 5.

  The LED 51 is an excitation light source that emits excitation light for exciting the semiconductor nanoparticle phosphor 11 included in the phosphor element 10. The LED 51 does not need to be disposed on the bottom surface 52 </ b> A of the reflector 52, and may be disposed near the bottom surface 52 </ b> A of the reflector 52 and on the side surface of the recess 5. Such a vicinity of the bottom surface 52 </ b> A is referred to as a bottom portion of the reflector 52. Further, as the excitation light source, another type of light source such as a semiconductor laser may be used.

  The sealing material 2 is a sealing material that seals the phosphor element 10 and the LED 51 and is an optically transparent dispersion medium. The sealing material 2 is made of resin, for example. In detail, the sealing material 2 is a polymer, epoxy, silicone and (meth) acrylate, silica glass, silica gel, siloxane, sol gel, hydrogel, agarose, cellulose, epoxy, polyether, polyethylene, polyvinyl, polydiacetylene, polyphenylene vinylene. , Polystyrene, polypyrrole, polyimide, polyimidazole, polysulfone, polythiophene, polyphosphate, poly (meth) acrylate, polyacrylamide, polypeptide, polysaccharide and combinations thereof.

  A mixture of the sealing material 2 and the phosphor element 10 formed inside the recess 5 is referred to as a wavelength conversion member 6. In the LED package 1, particularly the wavelength conversion member 6, the side from which the fluorescence emitted from the phosphor element 10 is emitted is referred to as the emission side. Of the surfaces of the members of the LED package 1, the surface on the emission side may be referred to as the upper surface.

  The phosphor element 10 is unevenly distributed on the emission side in the wavelength conversion member 6. More specifically, the phosphor element 10 is located on the emission side of the wavelength conversion member 6 with respect to the upper surface 51A of the LED 51. The upper surface 51A is a surface on the opposite side of the LED 51 from the surface in contact with the bottom surface 52A, and is a surface on the emission side. In FIG. 1, a plane 53 parallel to the bottom surface 52A and including the top surface 51A is shown. All the phosphor elements 10 are located on the emission side from the plane 53. However, there may be a case where a small amount of the phosphor element 10 exists on the side of the bottom surface 52A with respect to the flat surface 53, but such a light emitting device is also included in the technical scope of the present disclosure.

  Since the LED 51 generates heat when it emits light, it is preferable not to arrange the phosphor element 10 around the LED 51. By arranging the phosphor element 10 as shown in FIG. 1, it is possible to suppress the quantum efficiency of the semiconductor nanoparticle phosphor 11 from being lowered by the heat of the LED 51.

  FIG. 2 is a cross-sectional view showing the configuration of the phosphor element 10. As shown in FIG. 2, the phosphor element 10 includes an enclosure 13, a matrix 12 enclosed in the enclosure 13, and a semiconductor nanoparticle phosphor 11 dispersed in the matrix 12. The matrix 12 includes an ionic liquid or a structural unit derived from the ionic liquid.

  The shape of the phosphor element 10 is not limited to a spherical shape, and may be a cube or the like having a polygonal cross-sectional shape. The particle diameter (diameter) of the phosphor element 10 is preferably 1 μm or more and 30 μm or less. When the particle diameter of the phosphor element 10 is 30 μm or less, the phosphor element 10 tends to be dispersed in the sealing material 2 by the same process as that of the conventional phosphor.

  The semiconductor nanoparticle phosphor 11 is a nano-sized phosphor particle and is a single phosphor particle that does not scatter visible light. The semiconductor nanoparticle phosphor 11 is composed of one or more types of semiconductor crystals.

  The particle diameter (diameter) of the semiconductor nanoparticle phosphor 11 can be appropriately selected according to the raw material and the desired emission wavelength, and is not particularly limited. The particle diameter of the semiconductor nanoparticle phosphor 11 is, for example, in the range of 1 to 20 nm.

  The semiconductor nanoparticle phosphor 11 is preferably composed of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, InN, InP, InAs, InSb, AlP, AlS, AlAs, AlSb, GaN, GaP, GaAs, as semiconductor nanoparticles. It includes one or more semiconductor materials selected from the group consisting of GaSb, PbS, PbSe, Si, Ge, MgS, MgSe, MgTe, and combinations thereof.

  Further, the semiconductor nanoparticle phosphor 11 may be a two-component core type, a three-component core type, a four-component core type, a core-shell type or a core multi-shell type, doped nanoparticles or tilted nanoparticles known to those skilled in the art. It may be.

  Since the semiconductor nanoparticle phosphor 11 has an organic modifying group on its surface, it can prevent aggregation of the semiconductor nanoparticle phosphors 11. Moreover, since the surface of the semiconductor nanoparticle phosphor 11 has polarity, the semiconductor nanoparticle phosphor 11 can be favorably dispersed in a matrix including a structural unit derived from an ionic liquid. Therefore, it can suppress that the semiconductor nanoparticle fluorescent substance 11 deteriorates by aggregation.

  The matrix 12 is a dispersion medium for stably dispersing the semiconductor nanoparticle phosphor, and includes an ionic liquid or a structural unit derived from the ionic liquid. In the present specification, the “ionic liquid” means a salt in a molten state (normal temperature molten salt) even at normal temperature (for example, 25 ° C.), and is represented by the following general formula (1).

X ⁺ Y ⁻ (1)
In the general formula (1), X ⁺ is a cation selected from an imidazolium ion, a pyridinium ion, a phosphonium ion, an aliphatic quaternary ammonium ion, pyrrolidinium, and sulfonium. Of these, aliphatic quaternary ammonium ions are particularly preferred cations because of their excellent thermal and atmospheric stability.

In the general formula (1), Y ⁻ represents tetrafluoroborate ion, hexafluorophosphate ion, bistrifluoromethylsulfonylimido ion, perchlorate ion, tris (trifluoromethylsulfonyl) carbonate ion, trifluoro. An anion selected from lomethanesulfonate ion, trifluoroacetate ion, carboxylate ion, and halogen ion. Among these, bistrifluoromethylsulfonylimido ion is mentioned as a particularly preferable anion because it has excellent thermal and atmospheric stability.

  For example, the matrix 12 contains a resin containing a structural unit derived from an ionic liquid having a polymerizable functional group as a main component (for example, 80% by mass or more). Examples of the ionic liquid having a polymerizable functional group include 2- (methacryloyloxy) -ethyltrimethylammonium bis (trifluoromethanesulfonyl) imide and 1- (3-acryloyloxy-propyl) -3-methylimidazolium bis. (Trifluoromethanesulfonyl) imide etc. are mentioned.

  The matrix 12 may contain a resin containing a structural unit derived from an ionic liquid having no polymerizable functional group as a main component (for example, 80% by mass or more). Examples of the ionic liquid having no polymerizable functional group include N, N, N-trimethyl-N-propylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-methyl-2- (2- Methoxyethyl) ammonium bis (trifluoromethanesulfonyl) imide and the like.

  The resin containing the structural unit derived from the ionic liquid can be formed, for example, by curing the ionic liquid with heat or light using a crosslinking agent. As a curing method, a photocuring method in which ultraviolet rays are applied for curing, or a thermosetting method in which heat is applied for curing can be used.

  The above-mentioned substance as the matrix 12 does not have a vapor pressure and hardly evaporates, so that a stable state can be maintained. In addition, there is an effect of electrostatically stabilizing the surface of the semiconductor nanoparticle phosphor 11 so as to stably disperse it without agglomeration, and it becomes possible to maintain high luminous efficiency.

  The encapsulant 13 is a hollow and translucent capsule that defines an encapsulating space, and holds the matrix 12 in which the semiconductor nanoparticle phosphor 11 is dispersed in the encapsulating space. By covering the periphery of the matrix 12 with the inclusion body 13, the intrusion of oxygen and moisture into the matrix 12 can be suppressed. Thereby, degradation of the semiconductor nanoparticle phosphor 11 due to oxygen or moisture can be suppressed, and a decrease in efficiency of the semiconductor nanoparticle phosphor 11 can be suppressed.

  The material of the encapsulant 13 is not particularly limited as long as it is a light-transmitting material and blocks oxygen and moisture, and an inorganic material or a polymer material can be used. Inorganic materials have an excellent barrier property against oxygen and moisture. As the inorganic material, for example, silica, metal oxide, metal nitride, or the like can be used.

  Since the polymer material has flexibility, the impact resistance of the semiconductor nanoparticle phosphor 11 is improved when it is used as the material of the encapsulant 13. Polymer materials include acrylate polymers, epoxides, polyamides, polyimides, polyesters, polycarbonates, polythioethers, polyacrylonitriles, polydienes, polystyrene polybutadiene copolymers, parylene, silica-acrylate hybrids, polyetheretherketone, polyvinylidene fluoride, polyvinylidene chloride, Polydivinylbenzene, polyethylene, polypropylene, polyethylene terephthalate, polyisobutylene, polyisoprene, cellulose derivatives, polytetrafluoroethylene, and the like can be used.

(Production method)
The manufacturing method of the semiconductor nanoparticle phosphor 11 is not particularly limited, and any manufacturing method may be used. From the viewpoint that the technique is simple and low in cost, it is preferable to use a chemical synthesis method as a method for producing the semiconductor nanoparticle phosphor 11. In the chemical synthesis method, a target product can be obtained by dispersing a plurality of starting materials containing the constituent elements of the product in a medium and reacting them. Examples of such chemical synthesis methods include sol-gel method (colloid method), hot soap method, reverse micelle method, solvothermal method, molecular precursor method, hydrothermal synthesis method, or flux method.

  There are no particular restrictions on the method for manufacturing phosphor element 10. As a manufacturing method of the phosphor element 10, for example, the following method can be cited.

  After the matrix 12 in which at least one semiconductor nanoparticle phosphor 11 capped with an ionic modifier is dispersed is placed in a solution containing the material of the inclusion body 13, the inclusion body material is deposited. Thereby, the phosphor element 10 in which the surface of the matrix 12 is coated with the inclusion body 13 can be obtained.

  The following method can be illustrated as a manufacturing method of the LED package 1. First, the LED 51 is disposed on the bottom surface 52 </ b> A of the reflector 52. And only the sealing material 2 (1st sealing material) is inject | poured into the recessed part 5 of the reflector 52 (1st injection | pouring process). At this time, the sealing material 2 is injected so that the injected sealing material 2 covers the upper surface 51 </ b> A of the LED 51. Thereafter, the wavelength conversion member 6 is completed by further injecting the sealing material 2 (second sealing material) in which the phosphor elements 10 are dispersed (second injection step) and performing a curing process on the sealing material 2. To do.

[Embodiment 2]
Other embodiments of the present disclosure are described below. For convenience of explanation, members having the same functions as those described in the above embodiment are given the same reference numerals, and the description thereof will not be repeated.

  FIG. 3 is a cross-sectional view illustrating a configuration of an LED package 50 (light emitting device) according to the second embodiment. In FIG. 3, the distance between the bottom surface 52 </ b> A and the exit-side surface of the sealing material 2 is indicated by the symbol H. This distance is referred to as the height H of the wavelength conversion member 6. A plane parallel to the bottom surface 52 </ b> A and located at half the height H is denoted by reference numeral 54.

  In the LED package 50, in the wavelength conversion member 6, all the phosphor elements 10 are unevenly distributed on the emission side from the plane 54. In other words, the phosphor element 10 is held in the region on the emission side half of the sealing material 2. However, there may be a case where a small amount of the phosphor element 10 is present on the side of the bottom surface 52A from the flat surface 54, but such a light emitting device is also included in the technical scope of the present disclosure. That is, in the LED package 50, in the wavelength conversion member 6, substantially all the phosphor elements 10 are located on the emission side from the plane 54.

  In the LED package 50, the phosphor element 10 is separated from the bottom surface 52A by a distance of at least half the height H. Compared with the LED package 1, in the LED package 50, since the phosphor element 10 is further away from the LED 51, the deterioration of the semiconductor nanoparticle phosphor 11 due to the heat of the LED 51 can be more effectively suppressed.

(Production method)
As a manufacturing method of the LED package 50, the following method can be illustrated. First, the LED 51 is disposed on the bottom surface 52 </ b> A of the reflector 52. And only the sealing material 2 (1st sealing material) is inject | poured into the recessed part 5 of the reflector 52 (1st injection | pouring process). At this time, the sealing material 2 is injected so that the upper surface of the injected sealing material 2 is positioned on the emission side with respect to half of the height H. Then, the wavelength conversion member 6 is completed by inject | pouring further the sealing material 2 (2nd sealing material) in which the phosphor element 10 was disperse | distributed (2nd injection | pouring process), and performing the hardening process of the sealing material 2. FIG. To do.

[Embodiment 3]
Other embodiments of the present disclosure are described below.

  FIG. 4 is a cross-sectional view illustrating a configuration of an LED package 60 (light emitting device) according to the third embodiment. As shown in FIG. 4, the LED package 60 includes a first layer 55 formed by sealing the LED 51 with a sealing material 2 that does not include the phosphor element 10, and the phosphor element 10 with the sealing material 2. And a second layer 56 sealed with. The second layer 56 is located on the emission side with respect to the first layer 55.

  In FIG. 4, a flat surface 54 located at a height half the height H is shown. The boundary surface between the first layer 55 and the second layer 56 is located on the emission side with respect to the plane 54. That is, the height of the first layer 55 from the bottom surface 52 </ b> A is half or more of the total height H of the first layer 55 and the second layer 56.

  Thus, in the LED package 60, the phosphor element 10 is separated from the bottom surface 52A by a distance of at least half the height H. Compared with the LED package 1, in the LED package 60, since the phosphor element 10 is further away from the LED 51, the deterioration of the semiconductor nanoparticle phosphor 11 due to the heat of the LED 51 can be more effectively suppressed.

(Production method)
The following method can be illustrated as a manufacturing method of the LED package 60. First, the LED 51 is disposed on the bottom surface 52 </ b> A of the reflector 52. And only the sealing material 2 is inject | poured into the recessed part 5 of the reflector 52 (1st injection | pouring process). At this time, the sealing material 2 is injected so that the upper surface of the injected sealing material 2 is positioned on the emission side with respect to half of the height H. Then, the injected sealing material 2 is cured to form the first layer 55.

  Thereafter, the sealing material 2 in which the phosphor element 10 is dispersed is further injected (second injection step), and the sealing material 2 is cured to form the second layer 56.

  Thus, by forming the wavelength conversion member 6 in two steps, the first layer 55 that does not include the phosphor element 10 is formed in the vicinity of the LED 51, and the phosphor element 10 is disposed at a position away from the LED 51. You can be sure.

[Embodiment 4]
Other embodiments of the present disclosure are described below.

  FIG. 5 is a cross-sectional view illustrating a configuration of an LED package 70 (light emitting device) according to the fourth embodiment. As shown in FIG. 5, the LED package 70 includes a wavelength conversion member 6 in which the phosphor element 10 and the phosphor element 20 are sealed.

  The phosphor element 20 includes a semiconductor nanoparticle phosphor 11 that emits fluorescence having a wavelength different from that of the semiconductor nanoparticle phosphor 11 included in the phosphor element 10. For example, the phosphor element 10 may include the semiconductor nanoparticle phosphor 11 that emits red fluorescence, and the phosphor element 20 may include the semiconductor nanoparticle phosphor 11 that emits green fluorescence. Thus, the wavelength conversion member 6 which emits fluorescence of desired chromaticity is realizable by combining the phosphor elements 10 and 20 which emit fluorescence of different wavelengths.

  In the LED package 70, both the phosphor elements 10 and 20 are located on the emission side from the plane 54. Therefore, it can suppress that the semiconductor nanoparticle fluorescent substance 11 contained in fluorescent substance element 10 * 20 deteriorates with the heat | fever of LED51.

  Note that the combination of the phosphor elements 10 and 20 may be realized in the LED packages 1 and 60.

[Embodiment 5]
Other embodiments of the present disclosure are described below.

  FIG. 6 is a cross-sectional view illustrating a configuration of an LED package 80 (light emitting device) according to the fifth embodiment. As shown in FIG. 6, the LED package 80 includes a wavelength conversion member 6 in which the phosphor element 10 and the conventional phosphor 40 are sealed.

Since the phosphor element 10 can be handled in the same manner as the conventional phosphor 40, the phosphor element 10 and the phosphor 40 are mixed in the same process as the conventional process to manufacture the LED package 80 having a desired emission color. Can do. As conventional phosphor 40, for example, inorganic phosphors, organic pigments, rare earth activated oxynitride phosphor, CaAlSiN ₃ red phosphor or YAG: can be used Ce yellow phosphor.

  In the LED package 80, both the phosphor element 10 and the phosphor 40 are located on the emission side from the plane 54. Therefore, it can suppress that the semiconductor nanoparticle fluorescent substance 11 and the fluorescent substance 40 which are contained in the fluorescent substance element 10 deteriorate with the heat | fever of LED51.

The combination of the phosphor element 10 and the conventional phosphor 40 may be realized in the LED packages 1 and 60.
[Embodiment 6]
Other embodiments of the present disclosure are described below. FIG. 7 is a cross-sectional view illustrating a configuration of a phosphor element 10A according to the sixth embodiment. As shown in FIG. 7, pores 13 </ b> A penetrating from the wall surface to the internal space may be formed on the wall surface of the enclosure 13. The diameter of the pore 13A is, for example, 20 nm or more and 10 μm or less.

  Since the enclosure 13 has the pores 13A, after the enclosure 13 is produced, the matrix 12 in which the semiconductor nanoparticle phosphor 11 is dispersed is injected into the enclosure 13 to obtain the phosphor element 10A. Can be produced. When the diameter of the pore 13A is 20 nm or more and 10 μm or less, the matrix 12 in which the semiconductor nanoparticle phosphor 11 is dispersed can be efficiently injected into the encapsulant 13.

[Embodiment 7]
Other embodiments of the present disclosure are described below. FIG. 8 is a cross-sectional view illustrating a configuration of the phosphor element 30 according to the seventh embodiment. As shown in FIG. 8, the phosphor element 30 has a protective substrate 14 on the outermost side. In the present embodiment, the enclosure 13 may have the pores 13A.

There is no particular limitation on the material for forming the protective substrate 14, for example _{SiO 2,} Al ₂ O ₃ as at least one of the main _{components, ZnO, In 2 O 3,} SnO 2, TiO 2, silicone resins, epoxy resins, etc. Can be mentioned.

  By providing the protective substrate 14, high chemical stability can be imparted to the phosphor element 30. Moreover, when the pore 13A is formed in the enclosure 13, the liquid leakage of the ionic liquid from the pore 13A can be physically prevented, and the handleability is improved.

  One embodiment of the present disclosure will be described below. FIG. 9 is a cross-sectional view showing a plurality of types of LED packages used in this example. In the present embodiment, the semiconductor nanoparticles contained in the phosphor element 10 sealed in these LED packages using the LED packages 100, 110, 120, and 130 shown in FIGS. The maintenance rate of the quantum efficiency (QY) of the phosphor 11 was examined.

  An LED package 100 shown in FIG. 9A is a conventional LED package in which the phosphor element 10 exists around the LED 51. In the LED package 110 shown in FIG. 9B, the ratio of the height of the first layer 55 to the height of the second layer 56 is 30:70. In the LED package 120 shown in FIG. 9C, the ratio of the height of the first layer 55 to the height of the second layer 56 is 50:50. In the LED package 130 shown in FIG. 9D, the ratio of the height of the first layer 55 to the height of the second layer 56 is 80:20. The sum of the height of the first layer 55 and the height of the second layer 56 is 0.7 mm.

  These LED packages 100, 110, 120, and 130 were continuously turned on, and the change in the quantum efficiency of the semiconductor nanoparticle phosphor 11 included in the phosphor element 10 was examined. The output of the LED 51 is 30 mW in any LED package, and the wavelength of light emitted from the LED 51 is 45 nm.

  The results of the lighting test for the LED packages 100, 110, 120, and 130 are indicated by broken lines A, B, C, and D in FIG. The polygonal lines E and F show the test results when the semiconductor nanoparticle phosphor 11 is directly sealed without being encapsulated in the encapsulant 13. The broken line E shows the result for the case of only one layer (corresponding to (a) in FIG. 9), and the broken line F shows the result for the case of two layers (corresponding to (c) in FIG. 9).

  As shown in FIG. 10, a decrease in quantum efficiency was suppressed when the phosphor element 10 was moved away from the LED 51. As indicated by the broken lines C and D, the quantum efficiency of the semiconductor nanoparticle phosphor 11 is more reliably suppressed by moving the phosphor element 10 away from the bottom surface 52A by more than half the height H of the wavelength conversion member 6. It became clear that we could do it.

  In general, the lifetime of the light-emitting device is a time for decaying to 70% of the initial quantum efficiency. If the maintenance rate of quantum efficiency is 0.7 or more after lighting for 1000 hours or more, the variation in brightness becomes small and practical. By moving the phosphor element 10 away from the bottom surface 52A by more than half the height H of the wavelength conversion member 6, it is easy to realize an LED package that satisfies this standard.

  The present disclosure is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the embodiments can be obtained by appropriately combining technical means disclosed in different embodiments. Are also included in the technical scope of the present disclosure. Furthermore, a new technical feature can be formed by combining the technical means disclosed in each embodiment.

1, 50, 60, 70, 80 LED package 2 Sealing material 5 Recess 6 Wavelength conversion member 10, 10A, 20, 30 Phosphor element 11 Semiconductor nanoparticle phosphor 12 Matrix 13 Encapsulant 13A Pore 40 Phosphor 51 LED
51A Top surface 52 Reflector 52A Bottom surface

Claims (5)

A phosphor element comprising a semiconductor nanoparticle phosphor dispersed in a matrix;
A light source that emits excitation light;
A sealing material for sealing the phosphor element and the light source;
In the sealing material, the side from which the fluorescence emitted by the phosphor element is emitted is referred to as an emission side,
The phosphor element is unevenly distributed on the emission side in the sealing material.   The light emitting device according to claim 1, wherein the phosphor element is unevenly distributed in the sealing material on the emission side with respect to the light source. A reflector that reflects the fluorescence emitted from the phosphor element;
The light source is disposed at the bottom of the reflector;
The light-emitting device according to claim 1, wherein the phosphor element is unevenly distributed in a region on the emission side half of the sealing material. The sealing material is
A first layer for sealing the light source;
A second layer located on the emission side of the first layer,
4. The light emitting device according to claim 1, wherein the phosphor element is included in the second layer, which is included in the first layer. 5. A phosphor element comprising a semiconductor nanoparticle phosphor dispersed in a matrix;
A light source that emits excitation light;
A method of manufacturing a light emitting device comprising the phosphor element and a sealing material for sealing the light source,
A first injection step of injecting a first sealing material not including the phosphor element around the light source;
And a second injection step of injecting a second sealing material containing the phosphor element onto the layer formed by the first injection step.

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