JP5585421B2 - Wavelength conversion element and light source including the same - Google Patents

Description

  The present invention relates to a wavelength conversion element and a light source including the same.

  In recent years, attention has been paid to next-generation light sources such as light sources using light emitting diodes (LEDs) and laser diodes (LDs), such as fluorescent lamps and incandescent lamps. As an example of such a next-generation light source, for example, in Patent Document 1 below, a wavelength conversion member that absorbs part of light from an LED and emits yellow light on the light emitting side of the LED that emits blue light. A light source in which is arranged is disclosed. This light source emits white light which is a combined light of blue light emitted from the LED and yellow light emitted from the wavelength conversion member.

JP 2000-208815 A

  In recent years, there has been an increasing demand for further increasing the luminance of a light source using such a wavelength conversion member.

  This invention is made | formed in view of this point, The objective is to aim at the high brightness improvement of the light source using a wavelength conversion member.

  The wavelength conversion element according to the present invention includes a wavelength conversion member and at least two first reflective layers. The wavelength conversion member is formed by dispersing phosphor powder in a dispersion medium. The wavelength conversion member has a light incident surface and a light output surface that face each other in the optical axis direction. The at least two first reflective layers are each formed along a plane parallel to the optical axis direction inside the wavelength conversion member. The at least two first reflective layers divide the wavelength conversion member into a plurality of portions.

  When the wavelength conversion member is one in which the phosphor powder is dispersed in the dispersion medium, for example, unlike an optical member made only of glass, light incident on the wavelength conversion member is greatly scattered in the wavelength conversion member. Tend to. For this reason, for example, in the single wavelength conversion member, light incident from the light incident surface toward the light emission surface is likely to be emitted from the side surface due to scattering. For this reason, the intensity | strength of the synthetic | combination light radiate | emitted from the light-projection surface of a wavelength conversion member will become low.

  On the other hand, the wavelength conversion element according to the present invention is formed along a plane parallel to the optical axis direction inside the wavelength conversion member, and has at least two layers dividing the wavelength conversion member into a plurality of portions. A first reflective layer is provided. For this reason, a part of the light scattered toward the side surface is reflected by the reflection layer, and is effectively suppressed from being emitted from the side surface. Therefore, in the wavelength conversion element according to the present invention, the intensity of light emitted from the light exit surface can be increased. Therefore, by using the wavelength conversion element according to the present invention, the brightness of the light source can be increased.

  The at least two first reflective layers are preferably formed in parallel to each other. With this configuration, it is possible to improve the straightness of the light emitted from the wavelength conversion element.

  Moreover, it is preferable that the 1st reflection layer is laminated | stacked 3 or more layers. With this configuration, it is possible to improve the straightness of the light emitted from the wavelength conversion element.

  The wavelength conversion element according to the present invention includes at least two second reflection layers formed along a plane parallel to the optical axis direction and intersecting the first reflection layer inside the wavelength conversion member. Furthermore, it is preferable to provide. And it is preferable that the wavelength conversion part which extends along an optical axis direction by the 1st reflection layer and the 2nd reflection layer is partitioned and formed in the wavelength conversion member. In this configuration, the intensity of light emitted from the light exit surface can be further increased. Further, it is possible to further improve the straightness of the light emitted from the light emitting surface.

  The at least two second reflective layers are preferably formed in parallel to each other. In this configuration, the straightness of the light emitted from the wavelength conversion element can be further improved.

  Further, it is preferable that at least two second reflective layers and at least two first reflective layers are orthogonal to each other. With this configuration, it is possible to further improve the straightness of the light emitted from the light emitting surface.

  More preferably, the second reflective layer is laminated in three or more layers, and the wavelength conversion units are provided in a matrix. With this configuration, it is possible to further improve the straightness of the light emitted from the light emitting surface.

  The first reflective layer may be made of, for example, a dielectric multilayer film, but is preferably made of a metal, an alloy, or a white paint. This is because the first reflective layer made of a metal, an alloy, or a white paint has low wavelength dependency of reflectance and can be easily formed. Similarly, the second reflective layer may be made of, for example, a dielectric multilayer film, but is preferably made of a metal, an alloy, or a white paint. Specific examples of metals that are preferably used include Ag, Al, Au, Pd, Pt, Cu, Ti, Ni, and Cr. Specific examples of the alloy preferably used include an alloy containing one or more metals selected from the group consisting of Ag, Al, Au, Pd, Pt, Cu, Ti, Ni, and Cr. Specific examples of the white paint preferably used include, for example, a white color containing particles made of one or more metals and alloys selected from the group consisting of Ag, Al, Au, Pd, Pt, Cu, Ti, Ni, and Cr. Examples include paints.

  The phosphor powder is preferably an inorganic phosphor powder. The dispersion medium is preferably made of glass or ceramics. Thus, the heat resistance of a wavelength conversion element can be improved by making fluorescent substance powder and a dispersion medium into an inorganic material.

  The light source which concerns on this invention is equipped with the wavelength conversion element which concerns on the said invention, and the light emitting element which radiate | emits the excitation light of fluorescent substance powder toward the light-incidence surface of a wavelength conversion element.

  As described above, the wavelength conversion element according to the present invention can increase the intensity of light emitted from the light exit surface. Therefore, the light source according to the present invention has high luminance.

  According to the present invention, it is possible to increase the brightness of a light source using a wavelength conversion member.

It is a schematic diagram of the light source which concerns on 1st Embodiment. It is a schematic perspective view of the element body of the wavelength conversion element in the first embodiment. It is a schematic perspective view of the element main body of the wavelength conversion element in 2nd Embodiment. It is a schematic perspective view of the element main body of the wavelength conversion element in 3rd Embodiment. It is a schematic perspective view of the element main body of the wavelength conversion element in 4th Embodiment. It is a schematic diagram of the light source which concerns on 5th Embodiment.

  Hereinafter, an example of the preferable form which implemented this invention is demonstrated. However, the following embodiment is merely an example. The present invention is not limited to the following embodiments.

(First embodiment)
FIG. 1 is a schematic diagram of a light source according to the first embodiment. As shown in FIG. 1, the light source 1 includes a wavelength conversion element 11 and a light emitting element 10. The wavelength conversion element 11 emits light L2 having a longer wavelength than the light L0 when the light L0 emitted from the light emitting element 10 is irradiated. Further, a part of the light L0 is transmitted through the wavelength conversion element 11. For this reason, the wavelength conversion element 11 emits light L3 that is a combined light of the transmitted light L1 and the light L2. For this reason, the light L3 emitted from the light source 1 is determined by the wavelength and intensity of the light L0 emitted from the light emitting element 10 and the wavelength and intensity of the light L2 emitted from the wavelength conversion element 11. For example, when the light L0 is blue light and the light L2 is yellow light, white light L3 can be obtained.

  The light emitting element 10 is an element that emits excitation light of a phosphor powder described later to the wavelength conversion element 11. The kind of the light emitting element 10 is not particularly limited. The light emitting element 10 can be composed of, for example, an LED, an LD, an electroluminescence light emitting element, or a plasma light emitting element. From the viewpoint of increasing the luminance of the light source 1, the light emitting element 10 preferably emits high-intensity light. From this viewpoint, it is preferable that the light emitting element 10 is composed of an LED or an LD.

  In the present embodiment, the wavelength conversion element 11 includes an element body 11a, a wavelength selection filter layer 11b, and a reflection suppression layer 11c. However, in the present invention, the wavelength selection filter layer 11b and the reflection suppression layer 11c are not essential. The wavelength conversion element may be composed of only the element body, for example. Further, either the wavelength selection filter layer or the reflection suppression layer may be formed on both the light emitting surface and the light incident surface of the element body.

  The wavelength selection filter layer 11b is formed on the light incident surface of the element body 11a. The wavelength selection filter layer 11b transmits only light in a specific wavelength region of the light L0 emitted from the light emitting element 10 to the element body 11a, and suppresses transmission of light in other wavelength regions, and This is a layer that prevents the light L2 converted by the main body 11a from being emitted from the light incident surface (light emitting element 10) side. The wavelength selection filter layer 11b can be formed of, for example, a dielectric multilayer film.

  On the other hand, the reflection suppressing layer 11c is formed on the light emitting surface of the element body 11a. The reflection suppressing layer 11c is a layer that suppresses the light emitted from the element body 11a from being reflected by the light emitting surface and increases the emission rate of the light emitted from the element body 11a. The reflection suppression layer 11c can be formed of, for example, a dielectric multilayer film.

  FIG. 2 is a schematic perspective view of the element body 11a. As shown in FIG. 2, the element body 11 a includes a wavelength conversion member 12 and a plurality of reflection layers 13. In the present embodiment, the wavelength conversion member 12 is formed in a prismatic shape. The wavelength conversion member 12 has a light incident surface 12a, a light emitting surface 12b, and four side surfaces 12c to 12f. The light incident surface 12a and the light emitting surface 12b face each other in the optical axis direction (x direction).

  The wavelength conversion member 12 has a dispersion medium and a phosphor powder dispersed in the dispersion medium.

  The phosphor powder absorbs light L0 from the light emitting element 10 and emits light L2 having a longer wavelength than the light L0. The phosphor powder is preferably an inorganic phosphor powder. By using the inorganic phosphor powder, the heat resistance of the wavelength conversion member 12 can be improved.

Specific examples of inorganic phosphors that emit blue light when irradiated with ultraviolet to near-ultraviolet excitation light having a wavelength of 300 to 440 nm include Sr ₅ (PO ₄ ) ₃ Cl: Eu ²⁺ , (Sr, Ba) MgAl ₁₀ O _17. : Eu ^{2+ and the} like.

Specific examples of the inorganic phosphor that emits green fluorescence (fluorescence having a wavelength of 500 nm to 540 nm) when irradiated with excitation light having a wavelength of 300 to 440 nm are SrAl ₂ O ₄ : Eu ²⁺ , SrGa ₂ S _4. : Eu ^{2+ and the} like.

Specific examples of inorganic phosphors that emit green fluorescence (fluorescence having a wavelength of 500 nm to 540 nm) when irradiated with blue excitation light having a wavelength of 440 to 480 nm include SrAl ₂ O ₄ : Eu ²⁺ and SrGa ₂ S ₄ : Eu ^2+. Etc.

A specific example of a non-fluorescent material that emits yellow fluorescence (fluorescence having a wavelength of 540 nm to 595 nm) when irradiated with excitation light having a wavelength of 300 to 440 nm is ZnS: Eu ²⁺ .

Specific examples of the inorganic phosphor that emits yellow fluorescence (fluorescence having a wavelength of 540 nm to 595 nm) when irradiated with blue excitation light having a wavelength of 440 to 480 nm include Y ₃ (Al, Gd) ₅ O ₁₂ : Ce ^{2+ and the} like. Can be mentioned.

Specific examples of the inorganic phosphor that emits red fluorescence (fluorescence having a wavelength of 600 nm to 700 nm) when irradiated with excitation light of ultraviolet to near ultraviolet with a wavelength of 300 to 440 nm include Gd ₃ Ga ₄ O ₁₂ : Cr ³⁺ , CaGa _2. S ₄ : Mn ^{2+ and the} like can be mentioned.

Specific examples of inorganic phosphors that emit red fluorescence (fluorescence having a wavelength of 600 nm to 700 nm) when irradiated with blue excitation light having a wavelength of 440 to 480 nm include Mg ₂ TiO ₄ : Mn ⁴⁺ and K ₂ SiF ₆ : Mn ^4+. Etc.

The average particle diameter (D ₅₀ ) of the phosphor powder is not particularly limited. The average particle size (D ₅₀ ) of the phosphor powder is, for example, preferably about 1 μm to 50 μm, and more preferably about 5 μm to 25 μm. If the average particle size (D ₅₀ ) of the phosphor powder is too large, the emission color may be non-uniform. On the other hand, if the average particle diameter (D ₅₀ ) of the phosphor powder is too small, the emission intensity may be reduced.

  The content of the phosphor powder in the wavelength conversion member 12 is not particularly limited. The content of the phosphor powder in the wavelength conversion member 12 can be appropriately set according to the intensity of light emitted from the light emitting element 10, the light emission characteristics of the phosphor powder, the chromaticity of the light to be obtained, and the like. In general, the content of the phosphor powder in the wavelength conversion member 12 can be, for example, about 0.01% by mass to 30% by mass, and preferably 0.05% by mass to 20% by mass. It is more preferable that it is 0.08 mass%-15 mass%. When there is too much content of the phosphor powder in the wavelength conversion member 12, the porosity in the wavelength conversion member 12 will become high, and the emitted light intensity of the light source 1 may fall. On the other hand, if the content of the phosphor powder in the wavelength conversion member 12 is too small, sufficiently strong fluorescence may not be obtained.

  The dispersion medium is preferably, for example, a heat resistant resin, glass, or ceramic. Among them, an inorganic dispersion medium such as glass or ceramics that has particularly high heat resistance and hardly deteriorates due to the light L0 from the light emitting element 10 is more preferably used.

  Specific examples of the heat resistant resin include polyimide and the like. Specific examples of the glass include silicate glass, borosilicate glass, phosphate glass, and borophosphate glass. Specific examples of ceramics include metal nitrides such as zirconia, alumina, barium titanate, silicon nitride, and titanium nitride.

  A plurality of first reflective layers 13 are formed inside the wavelength conversion member 12. In the present embodiment, three or more first reflective layers 13 are formed. Each of the plurality of first reflective layers 13 is formed in a flat plate shape. Each of the plurality of first reflective layers 13 is formed to extend along the x direction (optical axis direction) and the y direction perpendicular to the x direction. That is, each of the plurality of first reflective layers 13 is formed along a plane parallel to the x direction (optical axis direction). The plurality of first reflective layers 13 are arranged at intervals from each other along the z direction perpendicular to the x direction and the y direction. That is, the plurality of first reflective layers 13 are opposed to each other in the z direction. Each of the plurality of first reflective layers 13 is exposed to the light incident surface 12a, the light emitting surface 12b, and the side surfaces 12e and 12f. For this reason, the wavelength conversion member 12 is partitioned into a plurality of wavelength conversion units 14 arranged in the z direction.

  In the present embodiment, the plurality of first reflective layers 13 are provided in parallel to each other. However, in the present invention, at least two reflective layers may not be arranged in parallel to each other.

  The first reflective layer 13 preferably has a high reflectance of the light L0 from the light emitting element 10, that is, the excitation light of the phosphor powder and the light (converted light) emitted from the phosphor powder. Specifically, the reflectance of the reflective layer 13 at each of the excitation wavelength of the phosphor powder and the wavelength of light emitted from the phosphor powder when the phosphor powder is irradiated with the light having the excitation wavelength is 60% or more. Preferably, it is 85% or more, more preferably 90% or more.

  From the viewpoint of realizing such reflectance, the reflective layer 13 is preferably made of, for example, a metal or an alloy. Specifically, the reflective layer 13 is made of, for example, a metal such as Ag, Al, Au, Pd, Pt, Cu, Ti, Ni, or Cr, an alloy containing at least one of these metals, or a white paint. It is preferable.

  Depending on the material of the reflective layer 13, if the reflective layer 13 and the wavelength conversion member 12 are directly adhered, the adhesion strength of the reflective layer 13 may not be sufficiently increased. For this reason, an adhesion layer may be formed between the reflective layer 13 and the wavelength conversion member 12. The adhesion layer can be formed of, for example, aluminum oxide, silicon oxide, chromium oxide, copper oxide, or the like.

  As described above, in the present embodiment, the plurality of reflective layers 13 are formed inside the wavelength conversion member 12. For this reason, it can suppress that the light which is scattered in the wavelength conversion member 12 and goes to the side surfaces 12c and 12d emits from the side surfaces 12c and 12d. More specifically, among the plurality of wavelength conversion units 14, the light of the wavelength conversion unit 14 a sandwiched by the reflection layer 13 in the z direction is suppressed by being reflected by the reflection layer 13 and emitted from the side surfaces 12 c and 12 d. The light exits from the light exit surface 12b. Therefore, the intensity of the light L3 emitted from the light emitting surface 12b of the wavelength conversion member 12 can be increased. Therefore, the luminance of the light source 1 can be increased.

  In addition, by providing a plurality of reflection layers 13, the straightness of the light L <b> 3 emitted from the wavelength conversion member 12 can be improved. From the viewpoint of further improving the straightness of the light L3, it is preferable to provide three or more reflective layers 13.

  Further, by providing the reflective layer 13, the average optical path length until the light incident on the wavelength conversion member 12 is emitted from the wavelength conversion member 12 can be increased. Therefore, the wavelength conversion efficiency in the wavelength conversion member 12 can be increased.

  In addition, the manufacturing method of the wavelength conversion element 11 is not specifically limited. The wavelength conversion element 11 can be manufactured, for example, by the following method.

  First, the element body 11a is produced. Specifically, a plate-like member made of a dispersion medium in which phosphor powder is dispersed for constituting the wavelength conversion unit is produced. This plate-shaped member can be produced, for example, by press-molding a mixed powder of a phosphor powder and a glass powder or a ceramic powder, followed by firing.

  Next, a reflective layer is formed on one surface of the plate-like member. The reflective layer can be formed by, for example, a CVD method, a sputtering method, a plating method, or the like. Alternatively, the reflective film may be formed by bonding using an adhesive or the like.

  Next, the element body 11a can be formed by laminating and bonding a plurality of plate-like members each having a reflective layer formed on one side.

  Also, for example, a mixed powder of phosphor powder and glass powder or ceramic powder is press-molded into a plate shape, and a plurality of layers obtained by applying a paste containing metal fine particles to one side of the obtained molded body are laminated, and then fired By doing so, the element body 11a can be produced.

  Finally, the wavelength conversion element 11 can be completed by forming the wavelength selection filter layer 11b and the reflection suppressing layer 11c by sputtering or CVD.

  Hereinafter, other examples and modifications of the preferred embodiment in which the present invention is implemented will be described. In the following description, members having substantially the same functions as those of the first embodiment are referred to by the same reference numerals, and description thereof is omitted.

(Second Embodiment)
FIG. 3 is a schematic perspective view of the element body of the wavelength conversion element according to the second embodiment.

  As shown in FIG. 3, in the present embodiment, a plurality of second reflection layers 15 are formed in the wavelength conversion member 12 in addition to the plurality of first reflection layers 13. Specifically, in the present embodiment, three or more second reflective layers 15 are provided. Each of the plurality of second reflective layers 15 is parallel to the x direction (optical axis direction) and along the x direction and a direction inclined in the x direction (a direction intersecting the first reflective layer 13). It is formed to extend. In the present embodiment, specifically, each of the plurality of second reflective layers 15 is formed to extend along the x direction and the z direction (direction perpendicular to the first reflective layer 13). . The plurality of second reflective layers 15 are arranged at intervals in the y direction. That is, the plurality of second reflective layers 15 are opposed to each other in the y direction. Each of the plurality of second reflective layers 15 reaches the light incident surface 12a, the light emitting surface 12b, and the side surfaces 12c and 12d. The plurality of second reflection layers 15 and the plurality of first reflection layers 13 define a plurality of prismatic wavelength conversion sections 16 arranged in a matrix. Therefore, in the present embodiment, not only light leakage from the side surfaces 12c and 12d but also light leakage from the side surfaces 12e and 12f can be suppressed. Therefore, the intensity of the light L3 emitted from the light emitting surface 12b can be further increased. Therefore, the luminance of the light source 1 can be further increased.

  In the present embodiment, the plurality of reflective layers 15 are provided in parallel to each other. However, in the present invention, at least two second reflective layers may not be provided in parallel to each other.

  The manufacturing method of the element body 11a in the present embodiment is not particularly limited. For example, the element body 11a may be manufactured by pasting together a rectangular columnar wavelength conversion member in which a reflective layer is formed on two adjacent side surfaces in a matrix. Alternatively, the element main body 11a may be manufactured by inserting a plurality of rectangular columnar wavelength conversion members into a metal folder formed in a lattice shape.

(Third and fourth embodiments)
FIG. 4 is a schematic perspective view of the element body of the wavelength conversion element according to the third embodiment. FIG. 5 is a schematic perspective view of the element body of the wavelength conversion element according to the fourth embodiment.

  In the first and second embodiments, the example in which the reflective layer is not provided on the side surfaces 12c to 12f of the wavelength conversion member 12 has been described. However, the present invention is not limited to this configuration. For example, as shown in FIGS. 4 and 5, the reflective layer 17 may be formed on the side surfaces 12 c to 12 f. By doing so, it can suppress more effectively that light leaks from the side surfaces 12c-12f. Therefore, the intensity of the light L3 emitted from the light emitting surface 12b can be further increased. Therefore, the luminance of the light source 1 can be further increased.

(Fifth embodiment)
FIG. 6 is a schematic diagram of a light source according to the fifth embodiment.

  As shown in FIG. 6, the light source 2 of the present embodiment is provided with a beam splitter 18. The light L0 from the light emitting element 10 is guided to the wavelength conversion element 11 side by the beam splitter 18. A reflection suppression layer 11c is formed on the light incident surface side of the wavelength conversion element 11, and a reflection layer 11d is formed on the opposite surface. Further, an adhesive layer (not shown) made of resin or solder is formed on the reflective layer 11d, and the substrate 19 made of glass, ceramics, metal, or the like and the wavelength conversion element 11 are fixed via the adhesive layer. ing. A part of the light L0 and the light emitted from the wavelength conversion member 12 are reflected to the beam splitter 18 side by the reflective layer 11d. Therefore, the light L3 is emitted toward the beam splitter 18 and is transmitted through the beam splitter 18 and emitted.

  As shown in FIG. 6, when the light source 2 has the substrate 19 and the wavelength conversion element 11 fixed via an adhesive layer, the wavelength conversion portions as shown in FIGS. 2 and 3 are formed in a layer or matrix form. By using the wavelength conversion element 11, peeling between the substrate 19 and the wavelength conversion element 11 due to heat generated when converting the light L0 emitted from the light emitting element 10 into the light L3 can be effectively suppressed.

  Hereinafter, the present invention will be specifically described based on Examples and Comparative Examples. However, the following examples are merely illustrative. The present invention is not limited to the following examples.

(Example)
In this example, a wavelength conversion element having a configuration substantially similar to that of the wavelength conversion element 11 in the second embodiment was manufactured in the following manner.

Specifically, first, 85% by mass of borosilicate glass powder and 15% by mass of sulfide phosphor powder (CaGa ₂ S ₄ , fluorescence wavelength: 561 nm) are mixed, press-molded, and then fired and cut. Thus, a wavelength conversion member having a thickness of 0.3 mm, a width of 0.3 mm, and a depth of 20 mm was produced. A 134 nm thick layer made of aluminum oxide was formed as an adhesion layer on the entire surface of the wavelength conversion member by a vacuum deposition method. Next, a reflective layer made of Ag having a thickness of 150 nm was formed on the adhesion layer by sputtering. Next, the wavelength conversion member on which the adhesion layer and the reflection layer are formed is laminated, and bonded, cut, and polished using an epoxy resin adhesive to form a matrix element body having a width of 2.1 mm square and a depth of 0.5 mm. Was made.

  Next, a total of 39 layers of silicon oxide layers and tantalum oxide layers were alternately formed on the light incident surface of the element body by vacuum vapor deposition to form a wavelength selection filter layer. On the other hand, a reflection suppressing layer was formed on the light emitting surface of the element body by alternately forming a total of four silicon oxide layers and tantalum oxide layers by vacuum deposition. The wavelength conversion element was completed through the above steps.

  The light incident surface of the produced wavelength conversion element was irradiated with light having a wavelength of 460 nm using an LD, and the intensity of the light emitted from the light emitting surface side was measured through a 1 mm square slit. As a result, the intensity of the light emitted from the wavelength conversion element of this example was 102 lm.

(Comparative example)
A wavelength conversion member having a width of 2.1 mm square and a depth of 0.5 mm was prepared in the same manner as in the above example, and the wavelength conversion member was used as a wavelength conversion element without forming an adhesion layer and a reflection layer on the surface of the wavelength conversion member. The same evaluation was performed. As a result, the intensity of the light emitted from the wavelength conversion element of this comparative example was 83 lm.

  From these results, it is understood that the intensity of light emitted from the light exit surface of the wavelength conversion element can be increased by providing at least two reflective layers facing the inside of the wavelength conversion member.

DESCRIPTION OF SYMBOLS 1, 2 ... Light source 10 ... Light emitting element 11 ... Wavelength conversion element 11a ... Element main body 11b ... Wavelength selection filter layer 11c ... Reflection suppression layer 11d ... Reflection layer 12 ... Wavelength conversion member 12a ... Light incident surface 12b ... Light emission surface 12c- 12f ... side surfaces 13, 15, 17 ... reflective layer 14 ... wavelength converter 16 ... wavelength converter 18 ... beam splitter 19 ... substrate

Claims (11)

A wavelength conversion element used for converting the wavelength of irradiation light of an LED or LD,
A wavelength conversion member having a light incident surface and a light output surface facing each other in the optical axis direction, the phosphor powder being dispersed in a dispersion medium;
Inside the wavelength conversion member, formed along a plane parallel to the optical axis direction, and at least two first reflective layers that divide the wavelength conversion member into a plurality of portions, and
A wavelength conversion element comprising: The wavelength conversion element according to claim 1, wherein the irradiation light of the LED or LD is ultraviolet light to near ultraviolet light having a wavelength of 300 to 440 nm or blue light having a wavelength of 440 to 480 nm. The first reflective layer is formed in parallel with each other, the wavelength conversion element according to claim 1 or 2. The wavelength conversion element according to any one of claims 1 to 3 , wherein three or more first reflection layers are laminated. In the wavelength conversion member, further comprising at least two second reflective layers formed along a plane parallel to the optical axis direction and intersecting the first reflective layer,
The wavelength conversion part which extends along the said optical axis direction by the said 1st reflection layer and the said 2nd reflection layer is divided and formed in the said wavelength conversion member, The any one of Claims 1-4. The wavelength conversion element as described in 2. The wavelength conversion element according to claim 5 , wherein the second reflective layers are formed in parallel to each other. The wavelength conversion element according to claim 5 or 6 , wherein the second reflective layer and the first reflective layer are orthogonal to each other. The second reflective layer are stacked three or more layers, the wavelength converting part is provided in a matrix, the wavelength conversion device as claimed in any one of claims 5-7. The first reflective layer is a metal, an alloy or a white paint, the wavelength conversion device as claimed in any one of claims 1-8. The wavelength conversion element according to any one of claims 1 to 9 , wherein the phosphor powder is an inorganic phosphor powder, and the dispersion medium is glass or ceramics. The wavelength conversion element according to any one of claims 1 to 10 ,
A light emitting element that emits excitation light of the phosphor powder toward the light incident surface of the wavelength conversion element;
A light source comprising

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