Light-emitting member, manufacturing method therefor, optical member, and light-emitting device

Abstract

To reduce unevenness in color and / or brightness of light exiting from a light exit surface.SOLUTION: A light-emitting member comprises a light-emitting unit with a first surface configured to emit light, and a film formed on the first surface. The film has a refractive index that differs from that of the light-emitting unit by 0.3 or more, contains a particular substance, and has a thickness in a range of 10 to 70 nm, inclusive.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a light-emitting member, a method for manufacturing the same, an optical member, and a light-emitting device.

Background Art

[0002] As disclosed in Patent Document 1, an optical member having an optical thin film formed thereon is known. As the optical thin film, for example, a metal oxide film is used. By using a metal oxide film, an antireflection film, a reflection film, a filter film, a retardation film, a surface protection film, etc. can be realized. In such an optical member, various optical characteristics are required depending on the usage state.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present disclosure is to reduce color unevenness and / or luminance unevenness of light emitted from a light-emitting surface.

Means for Solving the Problems

[0005] A light-emitting member according to an embodiment of the present disclosure has a first surface, a light-emitting portion from which light is emitted, and a film formed on the first surface, wherein the refractive index difference between the film and the light-emitting portion is 0.3 or more, the film contains particulate substances, and the film thickness is 10 nm or more and 70 nm or less.

[0006] In addition, a light-emitting member according to an embodiment of the present disclosure has a first surface, a light-emitting portion from which light is emitted, and a film formed on the first surface. The film has a refractive index difference of 0.3 or more between the film and the light-emitting portion, contains a particulate substance, and in the region where the film is formed, the ratio of the particulate substance to the area of the region is 30% or more and 80% or less.

[0007] In addition, an optical member according to an embodiment of the present disclosure includes a light-emitting member according to an embodiment of the present disclosure and a translucent plate-like member disposed on the second surface side, which is the opposite surface of the first surface of the light-emitting portion.

[0008] In addition, a light-emitting device according to an embodiment of the present disclosure includes a base portion having a bottom surface and a frame surrounding the bottom surface, a light-emitting element disposed on the bottom surface, and a light-emitting member according to an embodiment of the present disclosure or an optical member according to an embodiment of the present disclosure, and seals the space in which the light-emitting element is disposed.

[0009] In addition, a method for manufacturing a light-emitting member according to an embodiment of the present disclosure includes a step of preparing a light-emitting portion having a first surface and emitting light, a step of forming a film on the first surface, and a step of heating the film. In the step of forming the film, a film having a refractive index difference of 0.3 or more from the light-emitting portion and having a film thickness of 10 nm or more and 70 nm or less is formed. In the step of heating the film, the substance is granulated.

[0010] In addition, a method for manufacturing a light-emitting member according to an embodiment of the present disclosure includes a step of preparing a light-emitting portion having a first surface and emitting light, a step of forming a film on the first surface, and a step of heating the film. In the step of forming the film, a film containing a substance having a refractive index difference of 0.3 or more from the light-emitting portion is formed. In the step of heating the film, the substance is granulated, and in the region where the film is formed, the ratio of the particulate substance to the area of the region is 30% or more and 80% or less.

Advantages of the Invention

[0011] According to an embodiment of the present disclosure, color unevenness and / or luminance unevenness of light emitted from a light emitting surface can be reduced.

Brief Description of Drawings

[0012]

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Embodiments for Carrying Out the Invention

[0013] Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In the following description, terms indicating specific directions and positions (for example, "upper", "lower", and other terms including those terms) are used as necessary, but the use of those terms is for facilitating the understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meanings of those terms. Also, parts denoted by the same reference numerals in a plurality of drawings indicate the same or equivalent parts or members.

[0014] In addition, in the present disclosure, with respect to polygons such as triangles and quadrilaterals, those having a shape obtained by performing processing such as rounding, chamfering, corner rounding, or filleting at the corners of the polygon are also referred to as polygons. Also, not limited to the corners (ends of the sides), a shape obtained by performing processing on the middle part of the side is also referred to as a polygon in the same manner. That is, a shape obtained by performing partial processing while leaving the polygon as a base is included in the interpretation of the "polygon" described in the present disclosure.

[0015] Moreover, not limited to polygons, the same applies to words representing specific shapes such as trapezoids, circles, and unevenness. The same also applies when dealing with each side forming the shape. That is, even if a side has been processed at a corner or in the middle part, the processed part is also included in the interpretation of the "side". When distinguishing a "polygon" or "side" without partial processing from the processed shape, "strict" is added, and it is described as, for example, "strict quadrilateral", etc.

[0016] Furthermore, the embodiments described below exemplify a light-emitting member or the like for embodying the technical idea of the present invention, and do not limit the present invention thereto. In addition, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are not intended to limit the scope of the present invention only thereto, but are intended to be exemplified, unless otherwise specified. Also, the content described in one embodiment is applicable to other embodiments and modifications. In addition, the sizes and positional relationships of the members shown in the drawings may be exaggerated for clarity of explanation. Furthermore, in order to avoid excessive complexity of the drawings, a schematic diagram omitting the illustration of some elements may be used, or an end view showing only the cut surface as a cross-sectional view may be used.

[0017] 〈First Embodiment〉 FIG. 1 is a perspective view exemplifying a light-emitting member according to the first embodiment. FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1 exemplifying the light-emitting member according to the first embodiment.

[0018] As shown in FIGS. 1 and 2, the light-emitting member 10 has a composite member 13 and a film 15.

[0019] Each component of the light-emitting member 10 will be described.

[0020] (Composite member 13) The composite member 13 has a light-emitting portion 11 and a light-reflecting portion 12. However, the light-reflecting portion 12 is not an essential component and is provided as necessary.

[0021] The light-emitting portion 11 has an upper surface 11a, a lower surface 11b that is the opposite surface of the upper surface 11a, and a side surface 11c that intersects the upper surface 11a and the lower surface 11b. Note that the upper surface of the light-emitting portion 11 may be referred to as the first surface and the lower surface as the second surface. The side surface 11c connects the outer edge of the upper surface 11a and the outer edge of the lower surface 11b. The light-emitting portion 11 is, for example, a rectangular parallelepiped or a cube. In this case, both the upper surface 11a and the lower surface 11b of the light-emitting portion 11 are rectangular, and the light-emitting portion 11 has four rectangular side surfaces 11c. Here, the rectangle means a rectangle or a square.

[0022] However, the light-emitting unit 11 is not limited to a rectangular parallelepiped or a cube. That is, the planar shape of the light-emitting unit 11 is not limited to a rectangle, and can be any shape such as a circle, an ellipse, or a polygon. In some cases, viewing an object from the normal direction of the upper surface 11a of the light-emitting unit 11 may be referred to as a plan view, and the shape of the object viewed from the normal direction of the upper surface 11a of the light-emitting unit 11 may be referred to as a planar shape.

[0023] The light-emitting unit 11 can emit light incident from the lower surface 11b from the upper surface 11a, for example. That is, the upper surface 11a is a light-emitting surface from which light is emitted. The light-emitting unit 11 may have light-transmitting properties for transmitting light. In the present application, the light-transmitting property means that the transmittance with respect to light is 80% or more.

[0024] Since light is irradiated onto the light-emitting unit 11, it is preferable that the base material of the light-emitting unit 11 is formed mainly of an inorganic material that is not easily decomposed by light irradiation. The main material is, for example, ceramics. Examples of the ceramics used as the main material include aluminum oxide, aluminum nitride, silicon oxide, yttrium oxide, zirconium oxide, or magnesium oxide. It is preferable to select a material having a melting point of 1300°C to 2500°C as the main material of the ceramics so that the light-emitting unit 11 does not undergo quality changes such as deformation or discoloration due to heat. The light-emitting unit 11 is, for example, a sintered body formed mainly of ceramics.

[0025] The light-emitting unit 11 may be a wavelength conversion unit having a phosphor. When the light-emitting unit 11 is a wavelength conversion unit, the light-emitting unit 11 can convert, for example, light incident from the lower surface 11b into light of a different wavelength and emit the converted light from the upper surface 11a. The light-emitting unit 11 may emit a part of the incident light. The light-emitting unit 11 may convert all of the incident light into light of different wavelengths. In this case, the light incident on the light-emitting unit 11 is not emitted from the light-emitting unit 11.

[0026] When the light emitting unit 11 is a wavelength conversion unit, the light emitting unit 11 can be formed, for example, by sintering a phosphor and a translucent material such as aluminum oxide. The content of the phosphor can be 0.05% to 50% by volume based on the total volume of the ceramics. Further, for example, ceramics substantially composed only of the phosphor obtained by sintering the phosphor powder may be used. Further, the light emitting unit 11 may be formed of a single crystal of the phosphor.

[0027] Examples of the phosphor include yttrium aluminum garnet (YAG) activated with cerium, lutetium aluminum garnet (LAG) activated with cerium, silicate ((Sr, Ba)2SiO4) activated with europium, α-sialon phosphor, β-sialon phosphor, and the like. Among them, garnet-based phosphors such as YAG phosphor and LAG phosphor have good heat resistance.

[0028] For example, when the light emitting unit 11 has a YAG phosphor, when blue excitation light is incident from the lower surface 11b, white light can be emitted from the upper surface 11a by combining the blue excitation light and the fluorescence.

[0029] The light reflecting unit 12 is, for example, a frame-shaped member having a rectangular opening. The light reflecting unit 12 has an upper surface 12a, a lower surface 12b which is the opposite surface of the upper surface 12a, an inner side surface 12c connecting the inner edge of the upper surface 12a and the inner edge of the lower surface 12b, and an outer side surface 12d connecting the outer edge of the upper surface 12a and the outer edge of the lower surface 12b. The outer edge and the inner edge of the upper surface 12a and the outer edge and the inner edge of the lower surface 12b are, for example, rectangular. In this case, the light reflecting unit 12 has four rectangular inner side surfaces 12c and four rectangular outer side surfaces 12d. However, the outer edge and the inner edge of the upper surface 12a and the outer edge and the inner edge of the lower surface 12b are not limited to rectangles, and can be any shape such as a circle, an ellipse, or a polygon.

[0030] The light reflecting portion 12 is, for example, a sintered body formed mainly of ceramics. Examples of the ceramics used as the main material include aluminum oxide, aluminum nitride, silicon oxide, yttrium oxide, zirconium oxide, magnesium oxide, and the like. Among these, aluminum oxide is preferable in terms of high reflectivity. Note that the light reflecting portion 12 does not necessarily have to be mainly made of ceramics. The light reflecting portion 12 may be formed using, for example, a metal, a composite of ceramics and metal, or the like.

[0031] In the composite member 13, the inner surface 12c of the light reflecting portion 12 is connected to the side surface 11c of the light emitting portion 11. The composite member 13 has a flat plate shape, for example, a rectangular parallelepiped.

[0032] The upper surface 11a of the light emitting portion 11 and the upper surface 12a of the light reflecting portion 12 may form, for example, a continuous single plane. Also, the lower surface 11b of the light emitting portion 11 and the lower surface 12b of the light reflecting portion 12 may form, for example, a continuous single plane. The composite member 13 may have a shape in which the upper surface 11a and / or the lower surface 11b of the light emitting portion 11 protrudes more than the upper surface 12a and / or the lower surface 12b of the light reflecting portion 12. In this case, a part of the side surface 11c of the light emitting portion 11 is connected to the inner surface 12c of the light reflecting portion 12.

[0033] The light emitting portion 11 and the light reflecting portion 12 may be formed by joining separate bodies, or may be formed integrally. The light emitting portion 11 and the light reflecting portion 12 may be integrally formed by, for example, a sintered body. In the light emitting portion 11 and the light reflecting portion 12, it is also possible to adjust the porosity. The porosity can be adjusted by sintering conditions (sintering temperature, sintering time, heating rate), the particle size of the material, the concentration of the sintering aid, and the like.

[0034] For example, when forming the light-emitting part 11 and the light-reflecting part 12 using the same ceramics as the main material, the porosity of the light-reflecting part 12 is made larger than that of the light-emitting part 11. That is, the composite member 13 is formed such that the light-reflecting part 12 contains more voids than the light-emitting part 11. In this case, it is preferable to adjust the sintering conditions so that the porosity of the light-reflecting part 12 is about 10%. Thereby, a reflection region by air is formed at the boundary between the side surface 11c of the light-emitting part 11 and the inner surface 12c of the light-reflecting part 12, and the light hitting the inner surface 12c of the light-reflecting part 12 from the light-emitting part 11 side can be reflected to the light-emitting part 11 side.

[0035] (Film 15) The film 15 is a light-scattering film containing particulate substances. The film 15 can mainly scatter light in the wavelength range of 320 nm or more and 530 nm or less, for example. Here, the term "particulate" means that the film 15 does not have to be formed continuously and refers to a state containing independent particles. However, some of the particles may be connected to each other. The shape of the particles may be any shape including spherical, flat, star-shaped, irregular shapes, etc.

[0036] In the region where the film 15 is formed, it is preferable that the ratio of the particulate substances occupying the area of the region is 30% or more and 80% or less with respect to the area of the region. By satisfying this ratio, the effect of scattering incident light can be sufficiently obtained. Note that, in the region where the film 15 is formed, the ratio of the particulate substances occupying the area of the region can be measured by image processing of an SEM photograph (scanning electron microscope photograph) of the film 15.

[0037] The film thickness of the film 15 is preferably 10 nm or more and 70 nm or less, and more preferably 30 nm or more and 50 nm or less. If the film thickness becomes too thick, the luminous efficiency decreases, so the film 15 is required to be formed with an appropriate thickness. Also, if the film thickness of the film 15 is 10 nm or more and 70 nm or less, the substances contained in the film 15 are sufficiently granulated and the effect of scattering incident light can be sufficiently obtained. If the film thickness of the film 15 is 30 nm or more and 50 nm or less, the number of independent particles of the substances contained in the film 15 increases and the effect of scattering incident light becomes even greater.

[0038] The particulate matter contained in the film 15 preferably has a high refractive index in order to obtain the effect of scattering. The refractive index of the particulate matter contained in the film 15 is, for example, 2 or more. The particulate matter contained in the film 15 is, for example, niobium oxide. Further, the material forming the film 15 does not contain a material different from the particulate matter. The refractive index of niobium oxide is about 2.3 to 2.4. It is preferable to use a material with a high refractive index for the particulate matter contained in the film 15. Specifically, as niobium oxide, niobium pentoxide (Nb2O5) is cited as an example. Further, examples of the material with a high refractive index include tantalum oxide, zirconium oxide, titanium oxide, and the like.

[0039] (Light-emitting member 10) The film 15 is formed at least on the upper surface 11a of the light-emitting portion 11. The film 15 may extend from the upper surface 11a of the light-emitting portion 11 to the upper surface 12a of the light-reflecting portion 12. The film 15 may be formed on the entire upper surfaces of the upper surface 11a of the light-emitting portion 11 and the upper surface 12a of the light-reflecting portion 12 (that is, the entire upper surface of the composite member 13).

[0040] The refractive index difference between the film 15 and the light-emitting portion 11 is 0.3 or more. If the refractive index difference between the film 15 and the light-emitting portion 11 is 0.3 or more, the effect of scattering incident light can be sufficiently obtained. The greater the refractive index difference between the film 15 and the light-emitting portion 11, the greater the effect of scattering incident light, which is preferable.

[0041] When the main material of the light-emitting portion 11 is aluminum oxide, the refractive index of the light-emitting portion 11 is about 1.6 to 1.8. On the other hand, when the particulate matter contained in the film 15 is niobium oxide, as described above, the refractive index of the film 15 is about 2.3 to 2.4. That is, in this case, the refractive index difference between the film 15 and the light-emitting portion 11 is 0.3 or more. Further, a refractive index difference of 0.8 between the film 15 and the light-emitting portion 11 can be realized. The refractive index difference can be obtained, for example, from the refractive indices of the main materials in the film 15 and the light-emitting portion 11 respectively. In this case, the main material occupies 50% or more in its component.

[0042] In the light-emitting member 10, the upper surface 11a side of the light-emitting portion 11 on which the film 15 is formed serves as the light-emitting side, and the lower surface 11b side of the light-emitting portion 11 serves as the light-incident side. That is, the light incident on the light-emitting portion 11 is emitted via the film 15. Note that a part of the light may also be incident on the lower surface 12b of the light reflection portion 12.

[0043] The light reflection portion 12 reflects the light traveling from the light-emitting portion 11 toward the light reflection portion 12 on the inner surface 12c. The light traveling from the light-emitting portion 11 toward the light reflection portion 12 is the light incident on the light-emitting portion 11. When the light-emitting portion 11 is a wavelength conversion portion having a phosphor, the light reflection portion 12 reflects the light incident on the light-emitting portion 11 or the light wavelength-converted by the light-emitting portion 11 on the inner surface 12c. The light reflection portion 12 is preferably formed of a material having a high thermal conductivity that exhausts the heat generated by the light-emitting portion 11. The light reflection portion 12 can be formed of, for example, aluminum oxide (Al2O3), which is a ceramic material having a high thermal conductivity.

[0044] Note that the light-emitting member 10 may have a film other than the film 15. For example, a light-shielding film may be formed of a metal or the like on the film 15 formed on the upper surface 12a of the light reflection portion 12. The light-shielding film can be formed, for example, to have a film thickness in the range of 50 nm or more and 500 nm or less. By providing the light-shielding film, light leakage from other than the film 15 formed on the upper surface 11a of the light-emitting portion 11, which serves as the light-emitting surface, can be suppressed. Further, the film 15 may be provided on the light-shielding film.

[0045] (Manufacturing method of the light-emitting member 10) FIG. 3 is a diagram illustrating a manufacturing method of a light-emitting member according to the first embodiment. First, as shown in FIG. 3, a composite member 13 is prepared. The composite member 13 can be prepared, for example, by manufacturing from the light-emitting portion 11 and the light reflection portion 12. Alternatively, instead of manufacturing the composite member 13, the composite member 13 may be prepared by procuring it.

[0046] When manufacturing the composite member 13, the composite member 13 can be manufactured, for example, by joining the side surface 11c of the light emitting portion 11 and the inner surface 12c of the light reflecting portion 12 with an adhesive. Alternatively, the composite member 13 can be formed, for example, by integrally sintering the light emitting portion 11 and the light reflecting portion 12. In this case, for example, the powder materials forming the light emitting portion 11 and the light reflecting portion 12 of the sintered body can be integrally molded and sintered. For sintering, for example, a normal pressure sintering method, a spark plasma sintering method (SPS method), a hot press sintering method (HP method), etc. can be used.

[0047] Next, as shown in FIG. 4, a film 15 is formed on at least the upper surface 11a of the light emitting portion 11. The film 15 is, for example, a film containing niobium oxide. The film 15 may be formed on the entire upper surface 11a of the light emitting portion 11 and the upper surface 12a of the light reflecting portion 12. The film 15 can be formed, for example, by a sputtering method. At this point, the film 15 is not in a particulate state but is formed continuously. After forming the film 15, the film 15 is heated. By the step of heating the film 15, the substances contained in the film 15 are granulated. That is, by the step of heating the film 15, a film 15 containing the granulated substances is formed. By the step of heating the film 15, the substances contained in the film 15 are granulated, and for example, in the region where the film 15 is formed, the ratio of the particulate substances to the area of the region is 30% or more and 80% or less. Thereby, the light emitting member 10 is completed. Note that in the step of forming the film 15, the film 15 does not have to contain niobium oxide, and it may be niobium alone or niobium nitride. If the heating atmosphere in the step of heating the film 15 is an oxidizing atmosphere, a film of niobium or niobium nitride can be formed and granulated in the same manner.

[0048] From the perspective of atomizing the substance contained in the film 15, the film thickness of the film 15 is preferably 10 nm or more and 70 nm or less, and more preferably 30 nm or more and 50 nm or less. Also, from the perspective of atomizing the substance contained in the film 15, it is preferable to heat the film 15 at a temperature of 850 °C or more and 1000 °C or less, and more preferably heat the film 15 at a temperature of 900 °C or more and 950 °C or less. Further, the heat treatment is preferably performed in an air atmosphere for about 1 hour. Also, the heat treatment is preferably not more than 10 hours in an air atmosphere. Thereby, a good atomized state can be created. Note that the heating temperature mentioned here is the temperature condition at atmospheric pressure.

[0049] Note that it may also be a process of preparing only the light-emitting part 11 in the process of FIG. 3, forming the film 15 on the upper surface 11a of the light-emitting part 11 in the process of FIG. 4, and then heating the film 15. In this case, a light-emitting member 10 having the light-emitting part 11 and the film 15 and not having the light reflection part 12 is produced.

[0050] (Light scattering property of film 15) FIGS. 5 to 10 are SEM photographs related to the atomization of niobium oxide. FIG. 5 is an SEM photograph of a niobium oxide film before heating. FIG. 6 is an SEM photograph of a niobium oxide film after heating at 800 °C for 1 h (1 hour) under atmospheric pressure. FIG. 7 is an SEM photograph of a niobium oxide film after heating at 850 °C for 1 h under atmospheric pressure. FIG. 8 is an SEM photograph of a niobium oxide film after heating at 900 °C for 1 h under atmospheric pressure. FIG. 9 is an SEM photograph of a niobium oxide film after heating at 950 °C for 1 h under atmospheric pressure. FIG. 10 is an SEM photograph of a niobium oxide film after heating at 1000 °C for 1 h under atmospheric pressure.

[0051] From FIG. 5, it can be confirmed that the niobium oxide film before heating is formed continuously rather than in a particulate state. Also, as shown in FIGS. 6 to 10, the degree of atomization of niobium oxide changes depending on the heating temperature. At 800 °C, although atomization has occurred, the degree of atomization is low and there are many continuous parts. Therefore, the heating temperature for atomization is preferably 850 °C or more and 1000 °C or less. Further, the heating temperature is more preferably 900 °C or more and 950 °C or less where the ratio of particles is large.

[0052] Figures 11 to 16 are SEM photographs showing differences in the mode of niobium oxide particle formation depending on the film thickness of the niobium oxide (heating conditions: 950 °C for 1 h under atmospheric pressure). Figure 11 is an SEM photograph of the film after heating the niobium oxide film formed with a film thickness of 5 [nm] at 950 °C for 1 h under atmospheric pressure. Figure 12 is an SEM photograph of the film after heating the niobium oxide film formed with a film thickness of 10 [nm] at 950 °C for 1 h under atmospheric pressure. Figure 13 is an SEM photograph of the film after heating the niobium oxide film formed with a film thickness of 30 [nm] at 950 °C for 1 h under atmospheric pressure. Figure 14 is an SEM photograph of the film after heating the niobium oxide film formed with a film thickness of 50 [nm] at 950 °C for 1 h under atmospheric pressure. Figure 15 is an SEM photograph of the film after heating the niobium oxide film formed with a film thickness of 70 [nm] at 950 °C for 1 h under atmospheric pressure. Figure 16 is an SEM photograph of the film after heating the niobium oxide film formed with a film thickness of 100 [nm] at 950 °C for 1 h under atmospheric pressure.

[0053] From Figures 11 to 16, it can be seen that in order to granulate the niobium oxide film, the film thickness should not be too thin or too thick, and there is a suitable film thickness range. Specifically, looking at the degree of granulation, in order to granulate the niobium oxide film, the film thickness of the niobium oxide is preferably 10 nm or more and 70 nm or less, and more preferably 30 nm or more and 50 nm or less where the number of independent particles increases. Note that the more independent particles there are, the higher the scattering effect.

[0054] Considering the results of Figures 11 to 16 together with the results of Figures 5 to 10, it can be said that in order to granulate the niobium oxide film, it is preferable to form the niobium oxide with a film thickness of 10 nm or more and 70 nm or less and heat it at a temperature of 850 °C or more and 1000 °C or less. Further, more preferable conditions for granulating the niobium oxide film are to form the niobium oxide with a film thickness of 30 nm or more and 50 nm or less and heat it at a temperature of 900 °C or more and 950 °C or less. Note that the heating temperatures mentioned here are temperature conditions under atmospheric pressure.

[0055] Figures 17 to 20 are diagrams illustrating the changes in the linear transmittance of niobium oxide films with different film thicknesses before and after heating. Figure 17 is a diagram illustrating the changes in the linear transmittance of a niobium oxide film with a film thickness of 10 [nm] before and after heating. Figure 18 is a diagram illustrating the changes in the linear transmittance of a niobium oxide film with a film thickness of 30 [nm] before and after heating. Figure 19 is a diagram illustrating the changes in the linear transmittance of a niobium oxide film with a film thickness of 50 [nm] before and after heating. Figure 20 is a diagram illustrating the changes in the linear transmittance of a niobium oxide film with a film thickness of 70 [nm] before and after heating.

[0056] In Figures 17 to 20, the measurement sample is a sapphire plate with a thickness of about 400 μm and mirror-finished on both sides, on one surface of which a niobium oxide film with a predetermined film thickness (10 nm, 30 nm, 50 nm, 70 nm) is formed. Then, samples with different film thicknesses and heating temperatures are prepared, and the linear transmittance of each sample before and after heating the niobium oxide film is measured and shown in Figures 17 to 20.

[0057] Here, the linear transmittance is the ratio of the light perpendicularly emitted from the niobium oxide film to the light perpendicularly incident on the plane of the sapphire plate. In Figures 17 to 20, 'Sapphire' indicates the linear transmittance of the sapphire without the niobium oxide film formed, and 'After film formation' indicates the linear transmittance before heating.

[0058] As shown in Figures 17 to 20, for any film thickness of 10 nm, 30 nm, 50 nm, and 70 nm, the niobium oxide film after heating has a lower linear transmittance in the wavelength range of 400 nm to 800 nm compared to the niobium oxide film before heating. Also, in the range of 800 °C to 950 °C, the higher the heating temperature, the greater the decrease in the linear transmittance on the short-wavelength side, and the difference from the long-wavelength side tends to widen. In contrast, at 1000 °C, the linear transmittance on the short-wavelength side tends to be higher than that at 950 °C.

[0059] The reason for the decrease in the linear transmittance on the short - wave side within the heating temperature range of 800 °C to 950 °C is that the niobium oxide film becomes particulate due to heating and scatters the incident light. This is considered to be a phenomenon similar to Rayleigh scattering. From the results of FIGS. 5 to 16 described above, in order to make the niobium oxide film particulate, it is preferable to form the niobium oxide film with a film thickness of 30 nm or more and 50 nm or less and heat it at a temperature of 900 °C or more and 950 °C or less under atmospheric pressure. Also in FIGS. 17 to 20, when heated at 950 °C, the linear transmittance on the short - wave side decreases in a wide wavelength range, and it can be said that by heating at 950 °C, the niobium oxide film is appropriately particulate and ideal scattering is obtained.

[0060] In addition, in FIGS. 17 to 20, although the linear transmittance on the short - wave side also decreases to some extent in the film before heating, this is not because the scattering increases due to particulate formation, but because the light transmitted through the film decreases due to the influence of the refractive index of the niobium oxide film.

[0061] In this way, by heating the niobium oxide film to make it particulate, the light scattering by the niobium oxide particles increases, the linear transmittance on the short - wave side decreases, and the difference from the long - wave side tends to widen. By utilizing this characteristic, as described below, the color unevenness and / or luminance unevenness of the light emitted from the light - emitting surface of the light - emitting member 10 can be reduced.

[0062] For example, in the light - emitting member 10 shown in FIG. 1 and the like, when the film 15 is a niobium oxide film after heating and light in the short - wave wavelength range shown in FIGS. 17 to 20 is incident from the lower surface 11b side of the light - emitting portion 11, the incident light can be scattered. For example, when laser light with an emission peak wavelength in the range of 320 nm or more and 530 nm or less is incident from the lower surface 11b side of the light - emitting portion 11, the laser light diffuses and the intensity difference between the central portion and the outer peripheral portion of the light - emitting surface becomes smaller. Therefore, the color unevenness and / or luminance unevenness of the light emitted from the light - emitting surface of the light - emitting member 10 can be reduced.

[0063] Also, in the light-emitting member 10 shown in FIG. 1 and the like, the light-emitting portion 11 has a wavelength conversion portion having YAG as a phosphor, the film 15 is a niobium oxide film after heating. For example, when laser light having a peak emission wavelength in the range of 420 nm or more and 480 nm or less is incident from the lower surface 11b side of the light-emitting portion 11, white light is emitted from the light-emitting surface of the light-emitting member 10. Also in this case, the same effect as described above can be obtained. That is, since the laser light is diffused and the intensity difference between the central portion and the outer peripheral portion of the light-emitting surface of the light-emitting member 10 is reduced, color unevenness and / or luminance unevenness of the white light emitted from the light-emitting surface of the light-emitting member 10 can be reduced.

[0064] Further, by the diffusion of the laser light, the laser light returned by scattering can be excited by the phosphor of the light-emitting portion 11 and converted into fluorescence. Thereby, the concentration (volume of the phosphor) of the phosphor can be reduced, and the temperature characteristics of the light-emitting portion 11 (wavelength conversion portion) can be improved.

[0065] FIG. 21 is a diagram illustrating the relationship between the output of the laser light input to the light-emitting member and the luminous efficiency, and shows data when the film thickness of the film 15 is 30 nm as a representative. The sample is a light-emitting member 10 in which the light-emitting portion 11 has a wavelength conversion portion having YAG as a phosphor, and the film 15 is a niobium oxide film having a film thickness of 30 nm. An integrating sphere was used for the measurement. Also, as a reference, measurement was performed on a sample on which no niobium oxide film was formed.

[0066] As shown in FIG. 21, it can be seen that the luminous efficiency is improved by the light-emitting portion 11 having the niobium oxide film 15 after heating. This is presumably because a part of the laser light incident from the lower surface 11b side of the light-emitting portion 11 is backscattered by the film 15 to the lower surface 11b side, and the phosphor is re-excited by the backscattering, increasing the phosphor light emitted from the light-emitting surface of the light-emitting member 10. The increase in the phosphor light is also advantageous for reducing color unevenness and / or luminance unevenness.

[0067] <Second Embodiment> In the second embodiment, an example of an optical member using the light-emitting member according to the first embodiment is shown. In the second embodiment, the description of the same components as those in the already described embodiments may be omitted.

[0068] FIG. 22 is a perspective view illustrating the optical member according to the second embodiment. FIG. 23 is a cross-sectional view taken along line XXIII-XXIII of FIG. 22, illustrating the optical member according to the second embodiment. As shown in FIGS. 22 and 23, the optical member 20 includes a light-emitting member 10 and a plate-like member 21.

[0069] Each component of the optical member 20 will be described.

[0070] (Plate-like member 21) The plate-like member 21 is a translucent member. The plate-like member 21 has an upper surface 21a, a lower surface 21b that is the opposite surface of the upper surface 21a, and side surfaces 21c that intersect the upper surface 21a and the lower surface 21b. The side surfaces 21c connect the outer edge of the upper surface 21a and the outer edge of the lower surface 21b. The plate-like member 21 is, for example, a rectangular parallelepiped or a cube. In this case, both the upper surface 21a and the lower surface 21b of the plate-like member 21 are rectangular, and the plate-like member 21 has four rectangular side surfaces 21c.

[0071] However, the plate-like member 21 is not limited to a rectangular parallelepiped or a cube. That is, the planar shape of the plate-like member 21 is not limited to a rectangle, and can be any shape such as a circle, an ellipse, or a polygon.

[0072] The plate-like member 21 has a base material formed in a flat plate shape such as a rectangular parallelepiped. The base material of the plate-like member 21 can be formed, for example, using sapphire as the main material. Sapphire is a material with a relatively high transmittance and relatively high strength. In addition to sapphire, as the main material, for example, translucent materials including quartz, silicon carbide, or glass may be used. It can be used.

[0073] (Optical member 20) In the optical member 20, the surface of the plate-like member 21 on which the film 15 of the light-emitting member 10 is not formed is joined to the upper surface 21a. That is, the plate-like member 21 is disposed on the lower surface 11b side of the light-emitting portion 11 and the lower surface 12b side of the light-reflecting portion 12. The light-emitting member 10 forms a metallization film on a part of the region where the light-emitting member 10 is disposed on the upper surface 21a of the plate-like member 21 and a part of the lower surface 12b of the light-reflecting portion 12, respectively, and fixes the metallization films to each other using solder such as Au-Sn, thereby enabling joining with the plate-like member 21. When the base material of the plate-like member 21 is sapphire, since sapphire is a material having a relatively high thermal conductivity, the heat generated in the light-emitting member 10 can be dissipated.

[0074] Since the plate-like member 21 is translucent, the light incident from the lower surface 21b side of the plate-like member 21 reaches the film 15 via the light-emitting portion 11 and exits from the film 15 side. Therefore, due to the scattering caused by the granularity of the film 15, the same effect as that of the light-emitting member 10 can be obtained.

[0075] A break detection mechanism may be provided between the light-emitting member 10 and the plate-like member 21. The break detection mechanism can be realized, for example, by joining a wiring pattern provided on the lower surface side of the light-emitting member 10 and a wiring pattern provided on the upper surface 21a side of the plate-like member 21 using solder such as Au-Sn.

[0076] For example, the wiring pattern provided between the light-emitting member 10 and the plate-like member 21 is electrically connected to a detection circuit disposed outside the optical member 20. Then, the detection circuit monitors the change in the resistance value of the wiring pattern, and when the resistance value changes beyond a predetermined threshold value, the breakage of the light-emitting member 10 and / or the plate-like member 21 can be detected.

[0077] Since the plate-like member 21 is translucent, the break detection mechanism provided between the light-emitting member 10 and the plate-like member 21 is visible from the lower surface 21b side of the plate-like member 21. Therefore, in the manufacturing process of the optical member 20 and the like, it is possible to confirm whether the break detection mechanism is properly joined, and the quality can be stabilized.

[0078] <Third Embodiment> In the third embodiment, an example of a light-emitting device using the optical member according to the second embodiment is shown. In the third embodiment, the description of the same components as those in the already described embodiments may be omitted.

[0079] FIG. 24 is a perspective view illustrating the light-emitting device according to the third embodiment. FIG. 25 is a cross-sectional view taken along line XXV-XXV of FIG. 24, illustrating the light-emitting device according to the third embodiment. FIG. 26 is a perspective view of the light-emitting device according to the third embodiment with the optical member further removed. FIG. 27 is a plan view of the light-emitting device according to the third embodiment with the optical member further removed.

[0080] As shown in FIGS. 24 to 27, the light-emitting device 200 includes an optical member 20, a base 210, a light-emitting element 220, a submount 230, a light-reflecting member 240, a protective element 250, a temperature-measuring element 260, wirings 270, and a light-shielding member 280. The light-emitting device 200 may have at least the optical member 20, the base 210, and the light-emitting element 220. Further, the light-emitting device 200 may have a light-emitting member 10 instead of the optical member 20.

[0081] Each component of the light-emitting device 200 will be described.

[0082] (Base 210) The base 210 has an upper surface 210a, a lower surface 210b, a plurality of inner surfaces 210c, one or more outer surfaces 210d, and a bottom surface 210e. The base 210 has a concave shape that is recessed in the direction from the upper surface 210a to the lower surface 210b. Also, the base 210 has a rectangular outer shape in plan view, and the recess is formed inside this outer shape.

[0083] Also, in plan view, a frame is formed by one or more inner surfaces 210c that intersect the upper surface 210a. That is, the base 210 includes a frame that forms the bottom surface 210e and the inner surfaces 210c that reach above the bottom surface 210e. The recess including the bottom surface 210e of the base 210 is surrounded by this frame.

[0084] Further, the base 210 has one or more stepped portions 216 inside the frame. Note that the stepped portion 216 is composed of only the upper surface and the side surface that intersects the upper surface and extends downward. The one or more inner side surfaces 210c include the side surface that intersects the upper surface 210a of the base 210 and the side surface of the stepped portion 216.

[0085] The base 210 can be formed, for example, mainly from ceramics. For example, as the ceramics, aluminum nitride, silicon nitride, aluminum oxide, or silicon carbide can be used. Note that the base 210 is not limited to ceramics, and may be formed mainly from other insulating materials.

[0086] Also, one or more metal films are provided on the bottom surface 210e of the base 210. Also, one or more metal films are provided on the upper surface 210a of the base 210. Also, the one or more metal films provided on the bottom surface 210e include a metal film that is electrically connected to the metal film provided on the upper surface 210a.

[0087] Note that the frame of the base 210 does not have to be provided in the same plane as the bottom surface 210e. For example, the frame of the base 210 may be provided in a plane that is recessed more than the bottom surface 210e. Also, the base 210 does not have to be integrally formed, and for example, a frame may be joined to a plate-like member.

[0088] (Light-emitting element 220) The light-emitting element 220 is not particularly limited as long as it is an element that emits light. For example, a semiconductor laser element, a light-emitting diode (LED), or an organic light-emitting diode (OLED) can be used. In this embodiment, as an example, an example in which a semiconductor laser element is used as the light-emitting element 220 is shown. That is, the light-emitting element 220 in the following description is a semiconductor laser element.

[0089] The light-emitting element 220 has, for example, a rectangular outer shape in plan view. Also, a side surface that intersects one of the two short sides of the rectangle is an emission end surface of the light emitted from the light-emitting element 220. Also, the upper surface and the lower surface of the light-emitting element 220 have a larger area than the emission end surface.

[0090] Note that the light (laser light) emitted from the light-emitting element 220 has divergence and forms an elliptical far-field pattern (hereinafter referred to as "FFP") on a plane parallel to the light-emitting end face. Here, the FFP indicates the shape and light intensity distribution of the emitted light at a position away from the light-emitting end face.

[0091] The light emitted from the light-emitting element 220 forms an elliptical FFP on a plane parallel to the light-emitting end face of the light, with the layer direction of the plurality of semiconductor layers including the active layer as the minor axis and the stacking direction perpendicular thereto as the major axis. The layer direction corresponding to the minor axis is referred to as the horizontal direction of the FFP, and the stacking direction corresponding to the major axis is referred to as the vertical direction of the FFP.

[0092] Also, based on the light intensity distribution of the FFP of the light-emitting element 220, the light having an intensity of 1 / e 2 or more with respect to the peak intensity value is referred to as the light of the main part. Also, the angle corresponding to the full width at half maximum of this light intensity distribution is referred to as the divergence angle. The divergence angle in the vertical direction of the FFP is referred to as the vertical divergence angle, and the divergence angle in the horizontal direction of the FFP is referred to as the horizontal divergence angle.

[0093] As the light-emitting element 220, one in which the emission peak wavelength of the light emitted from the light-emitting element 220 is in the range of 320 nm to 530 nm, typically in the range of 430 nm to 480 nm, can be used. Examples of such a light-emitting element 220 include a semiconductor laser element containing a nitride semiconductor. As the nitride semiconductor, for example, GaN, InGaN, or AlGaN can be used. Note that the wavelength of the light emitted from the light-emitting element 220 is not limited to this.

[0094] (Submount 230) The submount 230 is configured, for example, in the shape of a rectangular parallelepiped and has a bottom surface, a top surface, and side surfaces. Also, the submount 230 has the smallest width in the vertical direction. Note that the shape is not limited to a rectangular parallelepiped. The submount 230 is formed, for example, using aluminum nitride or silicon carbide, but other materials may also be used. Also, a metal film is provided on the top surface of the submount 230.

[0095] (Light reflecting member 240) The light reflecting member 240 has a light reflecting surface 241 that reflects light. On the light reflecting surface, for example, a surface with a light reflectivity of 90% or more with respect to the peak wavelength of the irradiated light is provided. The light reflectivity here may be 100% or less than 100%.

[0096] Also, the light reflecting member 240 has a plurality of light reflecting surfaces 241. All of the plurality of light reflecting surfaces 241 are in a planar shape and are inclined with respect to the bottom surface, and include two light reflecting surfaces 241 with different inclination angles with respect to the bottom surface. Neither of these two light reflecting surfaces 241 has a perpendicular or parallel arrangement relationship with respect to the bottom surface. Also, the two light reflecting surfaces 241 are continuously connected to form an integral one reflection region. Note that the shape of the light reflecting surface 241 is not limited to a planar shape and may be, for example, a curved surface shape.

[0097] It is preferable to select a material that is heat resistant as the main material of the light reflecting member 240. For example, glass such as quartz or BK7 (borosilicate glass), a metal such as aluminum, or Si can be used. Also, the light reflecting surface can be formed, for example, using a metal such as Ag or Al, or a dielectric multilayer film of Ta2O5 / SiO2, TiO2 / SiO2, or Nb2O5 / SiO2. Note that A / B indicates a multilayer film in which a film of A and a film of B are laminated in order.

[0098] (Protection element 250) The protection element 250 is for preventing a specific element such as a light emitting element from being destroyed by an excessive current flowing through it. As the protection element 250, for example, a Zener diode formed of Si can be used.

[0099] (Temperature measurement element 260) The temperature measurement element 260 is an element used as a temperature sensor for measuring the surrounding temperature. As the temperature measurement element 260, for example, a thermistor can be used.

[0100] (Wiring 270) The wiring 270 is used for electrical connection between two components. As the wiring 270, for example, a metal wire can be used.

[0101] (Light-shielding member 280) The light-shielding member 280 can be formed of, for example, a resin having light-shielding properties. Here, the light-shielding property indicates the property of not transmitting light. In addition to the property of blocking light, the light-shielding property may be realized by utilizing the properties of absorbing light or reflecting light. The light-shielding member 280 can be formed, for example, by incorporating fillers such as a light diffusing material and / or a light absorbing material into the resin.

[0102] Examples of the resin for forming the light-shielding member 280 include epoxy resin, silicone resin, acrylate resin, urethane resin, phenol resin, BT resin, etc. Examples of the light-absorbing filler contained in the light-shielding member 280 include dark-colored pigments such as carbon black.

[0103] (Light-emitting device 200) In the light-emitting device 200, two light reflection members 240 are arranged on the bottom surface 210e of the base 210. The two light reflection members 240 are arranged on different metal films, and their lower surfaces are joined to the bottom surface 210e of the base 210. Further, the two light reflection members 240 are arranged, for example, symmetrically with respect to the point SP (see FIG. 27). In addition, in plan view, the upper end of the light reflection surface 241 of the two light reflection members 240 is parallel or perpendicular to the inner surface 210c or the outer surface 210d of the base 210. Here, the parallel or perpendicular means allowing a difference within ±5 degrees.

[0104] On the bottom surface 210e of the base 210, a protection element 250 and a temperature measurement element 260 are arranged. The protection element 250 is arranged and joined on the metal film on which one of the two light reflection members 240 is arranged. The temperature measurement element 260 is arranged and joined on a metal film different from the metal film on which the two light reflection members 240 are arranged.

[0105] On the bottom surface 210e of the base 210, two submounts 230 are arranged. The two submounts 230 are arranged on different metal films respectively, and their lower surfaces are joined to the bottom surface 210e of the base 210. Also, each of the two submounts 230 is arranged on the metal film on which the light reflection member 240 is arranged. Note that the submount 230 and the light reflection member 240 may be arranged on different metal films.

[0106] The light emitting element 220 is arranged on the bottom surface 210e of the base 210. Specifically, the light emitting element 220 is arranged on the submount 230. In the example of the light emitting device 200 shown in the figure, two light emitting elements 220 are arranged on the upper surfaces of different submounts 230 respectively, and the lower surfaces of the submounts 230 are joined to the bottom surface 210e of the base 210. Also, the two light emitting elements 220 are arranged point-symmetrically with respect to the point SP. That is, the point where the two light emitting elements 220 are symmetric and the point where the two light reflection members 240 are symmetric are at the same position. In the following description, this point SP will be referred to as the symmetric point.

[0107] In plan view, the emission end faces of the two light emitting elements 220 are not parallel or perpendicular to the inner surface 210c or the outer surface 210d of the base 210. Therefore, the emission end faces are not parallel or perpendicular to the upper end of the light reflection surface 241 either. That is, in plan view, the light emitting element 220 is arranged such that the emission end faces are oblique with respect to the inner surface 210c and the outer surface 210d of the base 210, or the upper end of the light reflection surface 241.

[0108] Instead of arranging the light-emitting element 220 obliquely, the light reflection member 240 may be arranged obliquely. That is, the light-emitting element 220 may be arranged parallel or perpendicular to the inner surface 210c or the outer surface 210d of the base 210, and the light reflection member 240 may be arranged so as not to be parallel or perpendicular. Here, the parallel or perpendicular allows a difference within ±5 degrees.

[0109] For each of the two light-emitting elements 220, the light emitted from the emission end face is irradiated onto the corresponding light reflection member 240. The corresponding light reflection member 240 is the light reflection member 240 arranged on the same metal film. The light-emitting element 220 is arranged such that at least the light of the main part is irradiated onto the light reflection surface 241.

[0110] Also, between the corresponding light-emitting element 220 and the light reflection member 240, the light-emitting element 220 is located farther from the symmetry point than the light reflection member 240. Therefore, the light emitted from the light-emitting element 220 travels in a direction approaching the symmetry point. Also, at least one of the two light-emitting elements 220 is arranged close to the temperature measurement element 260. Thereby, the temperature of the light-emitting element 220 can be measured well.

[0111] The submount 230 on which the light-emitting element 220 is arranged serves as a heat dissipation member for releasing the heat generated from the light-emitting element 220 in the light-emitting device 200. To make the submount 230 function as a heat dissipation member, it may be formed of a material having a higher thermal conductivity than the light-emitting element 220. Also, if it is formed of a material having a higher thermal conductivity than the bottom surface 210e of the base 210, a higher heat dissipation effect can be obtained.

[0112] Also, the submount 230 can serve to adjust the light emission position of the light-emitting element 220 in the light-emitting device 200. For example, when it is desired to make the light passing through the optical axis horizontal with the bottom surface 210e and irradiate a predetermined position of the light reflection surface 241, the submount 230 can be used as an adjustment member.

[0113] The light-emitting element 220, the protection element 250, and the temperature measurement element 260 are electrically connected to a metal film provided on the bottom surface 210e of the base 210 via corresponding wirings 270. For the electrical connection between these elements and an external power source, the metal film provided on the bottom surface 210e of the base 210 is used. Thereby, these elements and the external power source can be electrically connected via the metal film on the upper surface 210a of the base 210.

[0114] The plate-like member 21 of the optical member 20 is disposed on the upper surface side of the base 210. Specifically, the outer peripheral portion of the lower surface 21b of the plate-like member 21 is joined to the upper surface of the stepped portion 216 of the base 210. By joining the plate-like member 21 to the base 210, a closed space in which the light-emitting element 220 is disposed is formed. Thus, in the light-emitting device 200, the plate-like member 21 can serve as a lid member. Further, this closed space is formed in a hermetically sealed state. By being hermetically sealed, it is possible to suppress the dust collection of organic substances or the like on the light-emitting end surface of the light-emitting element 220.

[0115] When the light-emitting member 10 is used instead of the optical member 20, for example, the light reflection portion 12 of the light-emitting member 10 may be set to an appropriate size, and the outer peripheral portion of the lower surface 12b of the light reflection portion 12 may be joined to the upper surface of the stepped portion 216 of the base 210.

[0116] The main part of the light emitted by the light-emitting element 220 is reflected by the light reflection surface 241 of the light reflection member 240 and enters the plate-like member 21. The plate-like member 21 has translucency with respect to the light emitted by the light-emitting element 220. Further, the main part of the light enters the light-emitting portion 11 of the light-emitting member 10 constituting the optical member 20 after passing through the plate-like member 21.

[0117] The light-emitting member 10 has, on its lower surface, a light incident region where the main part of the light enters and a peripheral region thereof. In the light-emitting member 10, the light-emitting portion 11 forms the light incident region. In the light-emitting member 10, when the light-emitting portion 11 is a wavelength conversion portion having a phosphor, the light-emitting portion 11 emits second light obtained by converting the first light emitted from the light-emitting element 220 into light of a different wavelength.

[0118] The first light emitted from the light-emitting element 220 or the second light wavelength-converted by the light-emitting unit 11 is emitted to the outside of the light-emitting device 200 through the film 15 formed on the upper surface 11a of the light-emitting unit 11. That is, the upper surface of the film 15 formed on the upper surface 11a of the light-emitting unit 11 serves as the light-emitting surface of the light-emitting device 200. In the light-emitting member 10, when the light-emitting unit 11 is a wavelength-converting unit having a phosphor, the film 15 reduces the emission amount of the first light and increases the emission amount of the second light as compared with the state where the film 15 is not formed.

[0119] Note that when heat generated by wavelength conversion concentrates at a specific location, the light conversion efficiency by the light-emitting unit 11 is likely to decrease. Therefore, it is preferable that the distribution of the light incident on the light-emitting unit 11 is diffused. For example, it is preferable that the strong-intensity portions of the laser light emitted from each of the two light-emitting elements 220 do not overlap. For example, such control can be achieved by adjusting the light-reflecting surface 241 of the light-reflecting member 240.

[0120] The light-shielding member 280 is formed inside the frame formed by the upper surface 210a of the base 210. The light-shielding member 280 is formed so as to fill the gap between the base 210 and the light-emitting member 10. The light-shielding member 280 can be formed, for example, by pouring a thermosetting resin and curing it with heat. By providing the light-shielding member 280, light leakage is suppressed.

[0121] The light-shielding member 280 is in contact with the inner surface 210c that intersects the upper surface 210a of the base 210, the upper surface of the stepped portion 216 of the base 210, the side surface of the plate-like member 21, the upper surface of the plate-like member 21, and the side surface of the light-emitting member 10. Further, it does not reach the upper surface of the light-emitting member 10. Alternatively, even if it reaches the upper surface of the light-reflecting unit 12, it does not reach the upper surface of the light-emitting unit 11. Depending on the light-shielding member 280, when it is difficult to achieve light shielding with high precision up to the boundary between the light-emitting unit 11 and the light-reflecting unit 12, as described above, it is preferable to form a light-shielding film on the film 15 formed on the upper surface 12a of the light-reflecting unit 12 in the light-emitting member 10. Thereby, in the light-emitting device 200, light leakage from other than the light-emitting surface can be suppressed with high precision.

[0122] Since the light-emitting device 200 mounts the light-emitting member 10 having the light-scattering film 15 containing particulate matter, the laser light from the light-emitting element 220 reaches the film 15 and diffuses, reducing the intensity difference between the central portion and the outer peripheral portion of the light-emitting surface. Therefore, in the light-emitting device 200, color unevenness and / or luminance unevenness of the light emitted from the light-emitting surface can be reduced. When the light-emitting element 220 is a semiconductor laser element, since light with a small spot diameter is emitted, a high effect can be expected by reducing color unevenness and / or luminance unevenness of the light due to scattering.

[0123] When the light-emitting portion 11 of the light-emitting member 10 has a YAG phosphor and the light-emitting element 220 is a semiconductor laser element that emits blue light in the range of a peak emission wavelength of 420 nm or more and 480 nm or less, if the film 15 is not formed, in the emitted light, a portion with strong blue having high directivity and a portion with strong phosphor color are likely to occur.

[0124] On the other hand, since the light-emitting device 200 mounts the light-emitting member 10 having the light-scattering film 15 containing particulate matter, the highly directional blue light is scattered. As a result, in the emitted light, the portion with strong blue is weakened, and color unevenness and / or luminance unevenness of the light emitted from the light-emitting surface are reduced. As a result, good white light can be obtained from the light-emitting surface.

[0125] The light-emitting device 200 can be used, for example, in an in-vehicle headlight. Further, the light-emitting device 200 is not limited thereto and can be used as a light source for lighting, a projector, a head-mounted display, a backlight for other displays, and the like.

[0126] Although the preferred embodiments and the like have been described in detail above, the present invention is not limited to the above-described embodiments and the like, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope described in the claims.

Description of Reference Numerals

[0127] 10 Light-emitting member 11 Light-emitting section 11a, 12a, 21a, 210a Upper surface 11b, 12b, 21b, 210b Lower surface 11c, 21c Side surface 12 Light-reflecting section 12c, 210c Inner side surface 12d, 210d Outer side surface 13 Composite member 15 Film 20 Optical member 21 Plate-like member 200 Light-emitting device 210 Base section 216 Step section 220 Light-emitting element 230 Submount 240 Light-reflecting member 241 Light-reflecting surface 250 Protection element 260 Temperature measurement element 270 Wiring 280 Light-shielding member

Claims

1. a light emitting portion having a first surface and emitting light; a film formed on the first surface, The film has a refractive index difference of 0.3 or more between the film and the light-emitting portion, contains a particulate substance, and within the region in which the film is formed, the particulate substance occupies a proportion of 30% or more and 80% or less of the area of ​​the region.

2. providing a light emitting portion having a first surface and emitting light; forming a film on the first surface; and heating the film, In the step of forming the film, a film containing a substance having a refractive index difference of 0.3 or more with respect to the light emitting portion and having a film thickness of 10 nm to 70 nm is formed, A method for manufacturing a light-emitting member, comprising the step of heating the film to form the film containing the particulated substance.

3. providing a light emitting portion having a first surface and emitting light; forming a film on the first surface; and heating the film, In the step of forming the film, a film containing a substance having a refractive index difference of 0.3 or more with respect to the light emitting portion is formed, A method for manufacturing a light-emitting component, wherein in the process of heating the film, the substance is granulated so that in the region where the film is formed, the proportion of the particulate substance relative to the area of ​​the region is 30% or more and 80% or less.

Images