JP6627914B2

JP6627914B2 - Fluorescent member, optical component, and light emitting device

Info

Publication number: JP6627914B2
Application number: JP2018104451A
Authority: JP
Inventors: 徹 ▲高▼曽根; 佐野　雅彦; 雅彦佐野; 祐之井上; 正一山田; 卓史杉山
Original assignee: Nichia Corp
Current assignee: Nichia Corp
Priority date: 2017-08-31
Filing date: 2018-05-31
Publication date: 2020-01-08
Anticipated expiration: 2038-05-31
Also published as: JP2019045844A

Description

本発明は、蛍光部材、蛍光部材を含む光学部品、及び蛍光部材を含む発光装置に関する。 The present invention relates to a fluorescent member, an optical component including the fluorescent member, and a light emitting device including the fluorescent member.

特許文献１に記載の波長変換部材は、蛍光体とセラミックスバインダーとの焼成物からなる。 The wavelength conversion member described in Patent Document 1 is made of a fired product of a phosphor and a ceramic binder.

ＷＯ２０１７−０６４９５１WO2017-064951

従来の波長変換部材には、その輝度と強度を高いレベルで両立できる余地がある。 A conventional wavelength conversion member has room for achieving both its luminance and intensity at a high level.

本発明の一形態に係る蛍光部材は、複数の蛍光体粒子と、無機バインダーとを含み、光取出し面となる上面を有する。また、前記蛍光部材は複数の空隙を含み、前記上面と平行であり、且つ、前記蛍光体粒子及び前記空隙の双方を横切る一断面において、前記複数の空隙は、前記複数の蛍光体粒子のうちの少なくとも一つの蛍光体粒子の近傍に偏在している。 A fluorescent member according to an embodiment of the present invention includes a plurality of phosphor particles and an inorganic binder, and has an upper surface serving as a light extraction surface. Further, the fluorescent member includes a plurality of voids, is parallel to the upper surface, and in one cross section that traverses both the phosphor particles and the voids, the plurality of voids is one of the plurality of phosphor particles. Are localized near at least one of the phosphor particles.

上記によれば、輝度を高くして、且つ、一定の強度を維持した蛍光部材とすることができる。 According to the above, it is possible to provide a fluorescent member having high luminance and maintaining a constant intensity.

図１は、実施形態１に係る発光装置の概略図である。FIG. 1 is a schematic diagram of the light emitting device according to the first embodiment. 図２は、光学部品の上面図である。FIG. 2 is a top view of the optical component. 図３は、図２のIII−III線における断面図である。FIG. 3 is a sectional view taken along line III-III in FIG. 図４は、図３の点線枠内における断面図である。FIG. 4 is a cross-sectional view in the dotted frame of FIG. 図５は、図３のＶ−Ｖ線における断面図の一部を拡大した図である。FIG. 5 is an enlarged view of a part of the cross-sectional view taken along line VV of FIG. 図６は、実施例に係る蛍光部材のＳＥＭ画像である。FIG. 6 is an SEM image of the fluorescent member according to the example. 図７は、比較例に係る蛍光部材のＳＥＭ画像である。FIG. 7 is an SEM image of the fluorescent member according to the comparative example. 図８は、実施例に係る蛍光部材の照度を測定したデータである。FIG. 8 shows data obtained by measuring the illuminance of the fluorescent member according to the example. 図９は、比較例に係る蛍光部材の照度を測定したデータである。FIG. 9 shows data obtained by measuring the illuminance of the fluorescent member according to the comparative example. 図１０は、実施形態２に係る光学部品の上面図である。FIG. 10 is a top view of the optical component according to the second embodiment. 図１１は、図１０のＸＩ−ＸＩ線における断面図である。FIG. 11 is a sectional view taken along line XI-XI in FIG. 図１２は、実施形態２に係る光学部品の変形例の断面図である。FIG. 12 is a cross-sectional view of a modification of the optical component according to the second embodiment.

本発明を実施するための形態を、図面を参照しながら以下に説明する。ただし、以下に示す形態は、本発明の技術思想を具体化するためのものであって、本発明を限定するものではない。なお、各図面が示す部材の大きさや位置関係等は、説明を明確にするために誇張していることがある。また、同一の名称、符号については、同一もしくは同質の部材を示しているため、重複した説明は適宜省略する。 Embodiments for carrying out the present invention will be described below with reference to the drawings. However, the embodiments described below are for embodying the technical idea of the present invention, and do not limit the present invention. In addition, the size, the positional relationship, and the like of the members illustrated in each drawing may be exaggerated for clarity of description. Further, the same names and reference numerals indicate the same or similar members, and thus duplicated description will be appropriately omitted.

＜実施形態１＞
図１に本実施形態に係る発光装置１０００の概略図を示す。図２に光学部品１００の上面図を示し、図３に図２のIII−III線における断面図を示す。また、図４に図３の点線枠内の拡大図を示し、図５に図３のＶ−Ｖ線における断面図の一部を拡大した図を示す。 <First embodiment>
FIG. 1 shows a schematic diagram of a light emitting device 1000 according to the present embodiment. FIG. 2 shows a top view of the optical component 100, and FIG. 3 shows a cross-sectional view taken along line III-III of FIG. FIG. 4 shows an enlarged view in a dotted frame in FIG. 3, and FIG. 5 shows an enlarged view of a part of a cross-sectional view taken along line VV in FIG.

図１に示すように、発光装置１０００は、蛍光部材１０を含む光学部品１００と、蛍光部材１０に照射する励起光を出射する光源２００と、光源２００からの励起光を蛍光部材１０に向けて反射するミラー３００と、蛍光部材１０からの光を平行光束となるように結像するレンズ４００と、を備える。 As shown in FIG. 1, the light emitting device 1000 includes an optical component 100 including the fluorescent member 10, a light source 200 that emits excitation light to irradiate the fluorescent member 10, and directs the excitation light from the light source 200 to the fluorescent member 10. The mirror 300 includes a mirror 300 that reflects light and a lens 400 that forms an image of light from the fluorescent member 10 so as to form a parallel light flux.

図２〜図５に示すように、蛍光部材１０は、複数の蛍光体粒子１１と、無機バインダー１２と、を含み、光取出し面となる上面を有する。また、図５に示すように、蛍光部材１０は複数の空隙１３を含み、蛍光部材の上面と平行であり、且つ、蛍光体粒子１１及び空隙１３の双方を横切る一断面において、複数の空隙１３は、複数の蛍光体粒子１１のうちの少なくとも一つの蛍光体粒子１１の近傍に偏在している。 As shown in FIGS. 2 to 5, the fluorescent member 10 includes a plurality of phosphor particles 11 and an inorganic binder 12 and has an upper surface serving as a light extraction surface. As shown in FIG. 5, the fluorescent member 10 includes a plurality of voids 13, and is parallel to the upper surface of the fluorescent member and has a plurality of voids 13 in one cross section that traverses both the phosphor particles 11 and the voids 13. Are unevenly distributed near at least one of the plurality of phosphor particles 11.

上記の蛍光部材１０によれば、蛍光体粒子１１からの光の横方向（図３における左右の方向）への広がりを低減しながら、蛍光部材の強度を確保することができる。以下、この点について説明する。 According to the above-described fluorescent member 10, the intensity of the fluorescent member can be ensured while reducing the spread of the light from the phosphor particles 11 in the horizontal direction (the left-right direction in FIG. 3). Hereinafter, this point will be described.

蛍光体粒子と無機バインダーとを含む蛍光部材が知られている。蛍光体粒子からの光は無機バインダーにおいて横方向に伝搬して広がるため、通常であれば上方から観測した場合の輝度はある程度低下してしまう。そこで、蛍光部材の内部に複数の空隙を設けて屈折率の異なる領域を増やして散乱させやくすることにより、蛍光体粒子からの光の伝搬を抑制することが考えられる。しかしながら、蛍光部材において、輝度を高くするために空隙の数を多くすると蛍光部材の強度が低下し、強度を確保するために空隙の数を少なくすると蛍光体粒子からの伝搬を低減しにくくなる。 A fluorescent member including phosphor particles and an inorganic binder is known. Since the light from the phosphor particles propagates and spreads in the inorganic binder in the horizontal direction, the brightness when observed from above normally decreases to some extent. Therefore, it is conceivable to suppress the propagation of light from the phosphor particles by providing a plurality of voids inside the fluorescent member to increase the regions having different refractive indexes to facilitate scattering. However, in the fluorescent member, if the number of voids is increased in order to increase the luminance, the strength of the fluorescent member is reduced. If the number of voids is reduced in order to secure the strength, propagation from the phosphor particles becomes difficult to reduce.

そこで本実施形態では、蛍光体粒子１１に近い領域に複数の空隙１３を偏在させている。これにより、蛍光体粒子１１から遠く、空隙の少ない領域で蛍光部材１０の強度を確保しながら、蛍光体粒子１１に近く、空隙の多い領域で蛍光体粒子１１からの光の伝搬を防ぐことができる。したがって、輝度を高くしつつ、一定の強度を維持した蛍光部材１０とすることができる。 Therefore, in the present embodiment, the plurality of voids 13 are unevenly distributed in a region near the phosphor particles 11. Accordingly, it is possible to prevent the propagation of light from the phosphor particles 11 in a region close to the phosphor particles 11 and having many gaps while securing the strength of the fluorescent member 10 in a region far from the phosphor particles 11 and having few gaps. it can. Therefore, it is possible to obtain the fluorescent member 10 maintaining a constant intensity while increasing the luminance.

以下、発光装置１０００の構成要素について説明する。 Hereinafter, components of the light emitting device 1000 will be described.

（光学部品１００）
図２及び図３に示すように、光学部品１００は、基部５０と、基部５０の上面に接合された蛍光部材１０と、を含む。蛍光部材１０の下面には反射膜２０が設けられている。そして、反射膜２０の下面には拡散防止層３０が設けられており、拡散防止層３０の下面と基部５０の上面とが接合部材４０により接合されている。 (Optical component 100)
As shown in FIGS. 2 and 3, the optical component 100 includes a base 50 and the fluorescent member 10 joined to the upper surface of the base 50. A reflection film 20 is provided on the lower surface of the fluorescent member 10. The diffusion preventing layer 30 is provided on the lower surface of the reflection film 20, and the lower surface of the diffusion preventing layer 30 and the upper surface of the base 50 are joined by the joining member 40.

（蛍光部材１０）
図３に示すように蛍光部材１０は、光取出し面となる上面と、上面と反対側に位置する下面と、上面と下面とをつなぐ側面と、を有する。蛍光部材１０は、複数の蛍光体粒子１１と、無機バインダー１２と、複数の空隙１３と、を含む。そして、図５に示すように、蛍光部材１０の上面と平行であり、且つ、蛍光体粒子１１及び空隙１３の双方を横切る一断面（以下「横断面Ｘ」という。）において、複数の空隙１３が蛍光体粒子１１の近傍に偏在している。これにより、蛍光部材１０において光の伝搬を抑制して輝度を高くすることができるため、空隙がない場合に比較して、コントラスト比の高い蛍光部材１０とすることができる。コントラスト比は、例えば、蛍光部材１０の上面における発光強度分布をみて、最大輝度と、そこから１ｍｍ離れた位置における輝度と、の比として認識できる。上述の「偏在」とは、例えば、走査型電子顕微鏡（ＳＥＭ）により蛍光体粒子１１が１０個明確に確認できるスケールで撮影した写真を観察して、少なくとも１つの蛍光体粒子１１において、蛍光体粒子１１の表面と、そこから離間距離が０．１μｍである線とで挟まれた領域における空隙１３の密度が、それよりも外側の領域における空隙１３の密度よりも高いことを指す。また、「蛍光部材１０の上面と平行」には、蛍光部材１０の上面に完全に平行なものはもちろんのこと、±１０度傾いているものも含まれることとする。また、蛍光部材１０の上面が微視的に見て粗面である場合は、横断面Ｘは、巨視的に見たときの蛍光部材１０の平坦な上面と平行な一断面とする。 (Fluorescent member 10)
As shown in FIG. 3, the fluorescent member 10 has an upper surface serving as a light extraction surface, a lower surface opposite to the upper surface, and a side surface connecting the upper surface and the lower surface. The fluorescent member 10 includes a plurality of phosphor particles 11, an inorganic binder 12, and a plurality of voids 13. Then, as shown in FIG. 5, in one section (hereinafter, referred to as “cross section X”) that is parallel to the upper surface of the fluorescent member 10 and crosses both the phosphor particles 11 and the gap 13, the plurality of gaps 13 are provided. Are unevenly distributed near the phosphor particles 11. Thereby, the luminance can be increased by suppressing the propagation of light in the fluorescent member 10, so that the fluorescent member 10 having a higher contrast ratio can be obtained as compared with a case where there is no gap. The contrast ratio can be recognized, for example, as a ratio between the maximum luminance and the luminance at a position 1 mm away from the light emission intensity distribution on the upper surface of the fluorescent member 10. The above-mentioned “localization” refers to, for example, observing a photograph taken by a scanning electron microscope (SEM) on a scale in which ten phosphor particles 11 can be clearly confirmed, and using at least one phosphor particle 11 It indicates that the density of the voids 13 in a region sandwiched between the surface of the particle 11 and a line having a separation distance of 0.1 μm is higher than the density of the voids 13 in a region outside the surface. The term “parallel to the upper surface of the fluorescent member 10” includes not only those completely parallel to the upper surface of the fluorescent member 10 but also those inclined ± 10 degrees. When the upper surface of the fluorescent member 10 is microscopically rough, the cross section X is a cross section parallel to the flat upper surface of the fluorescent member 10 when viewed macroscopically.

複数の空隙１３は、蛍光部材１０の上面から深さ方向に設けてもよい。つまり、図４に示すように、蛍光部材１０の上面と垂直をなし、且つ、蛍光体粒子１１及び空隙１３の双方を横切る一断面（以下「縦断面Ｙ」という。）においても、複数の空隙１３が設けられていてもよい。また、蛍光部材１０の上面から内部に入る光の伝搬も抑制できることから、例えば、１０μｍ以上離れた複数の横断面Ｘにおいて、蛍光体粒子１１の近傍に複数の空隙１３が偏在していることが好ましい。 The plurality of voids 13 may be provided in the depth direction from the upper surface of the fluorescent member 10. That is, as shown in FIG. 4, even in one section perpendicular to the upper surface of the fluorescent member 10 and crossing both the phosphor particles 11 and the gap 13 (hereinafter, referred to as “vertical section Y”), a plurality of gaps are provided. 13 may be provided. In addition, since the propagation of light entering the inside from the upper surface of the fluorescent member 10 can be suppressed, for example, in the plurality of cross sections X separated by 10 μm or more, the plurality of voids 13 may be unevenly distributed near the phosphor particles 11. preferable.

蛍光部材１０の形状は、蛍光部材１０を作製しやすいことから、一方向に長い直方体、又は立方体とすることができ、直方体とすることが好ましい。直方体である場合は、上方から見て、蛍光部材１０の左右方向の長さ（蛍光部材１０の幅であり図２の横方向の長さに該当する。）は１０ｍｍ以上１５ｍｍ以下の範囲内とすることが好ましく、蛍光部材１０の上下方向の長さ（蛍光部材１０の奥行きであり、図２の縦方向の長さに該当する。）は２ｍｍ以上５ｍｍ以下の範囲内とすることが好ましい。前述の下限値以上の長さとすることにより、励起光が照射される領域を変えることができ、前述の上限値以下の長さとすることにより必要以上に蛍光部材１０の面積が大きくなりすぎることを抑制することができる。 The shape of the fluorescent member 10 can be a rectangular parallelepiped or a cube that is long in one direction because the fluorescent member 10 can be easily manufactured, and is preferably a rectangular parallelepiped. In the case of a rectangular parallelepiped, when viewed from above, the length of the fluorescent member 10 in the left-right direction (the width of the fluorescent member 10 and corresponds to the length in the horizontal direction of FIG. 2) is within a range of 10 mm or more and 15 mm or less. The length of the fluorescent member 10 in the vertical direction (the depth of the fluorescent member 10 and corresponds to the length in the vertical direction in FIG. 2) is preferably in a range of 2 mm or more and 5 mm or less. By setting the length to the above-described lower limit or more, the region irradiated with the excitation light can be changed, and by setting the length to the above-described upper limit or less, the area of the fluorescent member 10 becomes unnecessarily large. Can be suppressed.

蛍光部材１０の厚み（図３の上下方向の長さ）は、５０μｍ以上２００μｍ以下の範囲内にすることが好ましく、７０μｍ以上１３０μｍ以下の範囲内にすることがさらに好ましい。前述の下限値以上の厚みとすることにより励起光と蛍光との混色光の色度の調整がしやすくなり、前述の上限値以下の厚みとすることにより、発熱しやすい上面側の蛍光体粒子１１から基部５０までの距離を短くすることができるため、蛍光部材１０で生じる熱を基部５０に発散しやすくなる。 The thickness of the fluorescent member 10 (the length in the vertical direction in FIG. 3) is preferably in the range of 50 μm to 200 μm, and more preferably in the range of 70 μm to 130 μm. When the thickness is not less than the above lower limit, the chromaticity of the mixed light of the excitation light and the fluorescent light can be easily adjusted, and when the thickness is not more than the above upper limit, the phosphor particles on the upper surface side which easily generates heat can be obtained. Since the distance from 11 to the base 50 can be shortened, heat generated in the fluorescent member 10 is easily radiated to the base 50.

図１に示すように、蛍光部材１０において、蛍光体粒子１１を励起する励起光の入射面と蛍光体粒子１１からの蛍光を取り出す光取出面とは同じ面であり、且つ、その面に対して励起光が斜め方向から入射する光学部品１００であることが好ましい。このような光学部品１００は励起光が上方（真上）から取り出されにくいため、蛍光部材１０の上方から取り出される光において蛍光の色が強く励起光の色が弱くなりやすい。例えば励起光が青色であり、蛍光が黄色である場合は黄色の強い光が取り出されやすくなる。これに対して、蛍光部材１０によれば、励起光を空隙１３で散乱させることができるため、最終的に得られる混色光において励起光の色を増やすことができる。 As shown in FIG. 1, in the fluorescent member 10, the incident surface of the excitation light for exciting the phosphor particles 11 and the light extraction surface for extracting the fluorescence from the phosphor particles 11 are the same surface, and Preferably, the optical component 100 is such that the excitation light is incident from an oblique direction. In such an optical component 100, since the excitation light is difficult to be extracted from above (directly above), the color of the fluorescent light in the light extracted from above the fluorescent member 10 is likely to be strong and the color of the excitation light is likely to be weak. For example, when the excitation light is blue and the fluorescence is yellow, strong yellow light is easily extracted. On the other hand, according to the fluorescent member 10, since the excitation light can be scattered in the gap 13, the color of the excitation light in the finally obtained mixed light can be increased.

（蛍光体粒子１１）
蛍光体粒子１１としては、例えば、ＹＡＧ（ＹｔｔｒｉｕｍＡｌｕｍｉｎｕｍＧａｒｎｅｔ）系蛍光体、ユウロピウム及び／又はクロムで賦活された窒素含有アルミノ珪酸カルシウム（ＣａＯ−Ａｌ_２Ｏ_３−ＳｉＯ_２）蛍光体、ユウロピウムで賦活されたシリケート（（Ｓｒ，Ｂａ）_２ＳｉＯ_４）蛍光体、αサイアロン蛍光体、βサイアロン蛍光体を用いることができる。中でも特に、ＹＡＧ系蛍光体を用いることが好ましい。ＹＡＧ系蛍光体は、比較的耐熱性の高い材料であるため、励起光による劣化を低減できるためである。ここで、ＹＡＧ系蛍光体には、例えばＹの少なくとも一部をＴｂに置換したものや、Ｙの少なくとも一部をＬｕに置換したものも含まれる。また、ＹＡＧ系蛍光体は、組成中にＧｄやＧａ等が含まれるものであってもよい。 (Phosphor particles 11)
Examples of the phosphor particles 11 include a YAG (Yttrium Aluminum Garnet) phosphor, a nitrogen-containing calcium aluminosilicate activated by europium and / or chromium (CaO—Al ₂ O ₃ —SiO ₂ ) phosphor, and an activation by europium. Silicate ((Sr, Ba) ₂ SiO ₄ ) phosphor, α-sialon phosphor, and β-sialon phosphor can be used. Among them, it is particularly preferable to use a YAG-based phosphor. This is because the YAG-based phosphor is a material having relatively high heat resistance, so that deterioration due to excitation light can be reduced. Here, the YAG-based phosphor includes, for example, a phosphor in which at least a part of Y is substituted by Tb and a phosphor in which at least a part of Y is substituted by Lu. The YAG-based phosphor may contain Gd, Ga, or the like in the composition.

蛍光体粒子１１の粒径は、例えば、１μｍ以上２０μｍ以下の範囲内とすることが好ましく、３μｍ以上６μｍ以下の範囲内とすることがさらに好ましい。前述の下限値以上の粒径とすることにより空隙１３を設けやすくなり、前述の上限値以下の粒径とすることにより蛍光部材１０に蛍光体粒子１１を満遍なく配置しにくくなる。粒径の測定方法としては、例えば、蛍光体粒子が１０個写るスケールのＳＥＭ画像で、円形に近い形状の蛍光体粒子１１の最短と最長の平均を求めることにより測定することができる。 The particle size of the phosphor particles 11 is, for example, preferably in a range of 1 μm to 20 μm, and more preferably in a range of 3 μm to 6 μm. By setting the particle size to be equal to or larger than the lower limit described above, it is easy to form the voids 13, and by setting the particle size to be equal to or smaller than the above upper limit, it becomes difficult to uniformly arrange the phosphor particles 11 on the fluorescent member 10. The particle diameter can be measured, for example, by obtaining the average of the shortest and longest lengths of the phosphor particles 11 having a shape close to a circle in a SEM image of a scale in which 10 phosphor particles appear.

蛍光部材１０における蛍光体粒子１１は、４０質量％以上７０質量％以下の範囲内にあることが好ましく、４５％質量以上６０％質量以下の範囲内にあることがさらに好ましい。前述の下限値以上の質量％とすることにより、空隙１３を形成しやすくして蛍光体粒子１１の伝搬を抑制しやすくすることができる。また、前述の上限値以下の質量％とすることにより、無機バインダー１２の質量％を確保することができるため蛍光部材１０の強度の低下を抑制しやすくなり、且つ、蛍光体粒子１１が発する熱を発散しやすくなる。特に、蛍光体粒子１１を励起する励起光の入射面と蛍光体粒子１１からの蛍光を取り出す光取出面とは同じ面である光学部品１００においては、蛍光体粒子１１の質量％が低いと、蛍光部材１０に入射した光が蛍光体粒子１１に当たらずに反射膜２０に用いられる金属で吸収される可能性があるが、蛍光体粒子１１の質量を一定以上確保することにより金属で吸収される励起光を減らすことができる。 The phosphor particles 11 in the fluorescent member 10 are preferably in a range of 40% by mass to 70% by mass, and more preferably in a range of 45% by mass to 60% by mass. By setting the mass% to be equal to or more than the lower limit described above, it is possible to easily form the void 13 and easily suppress the propagation of the phosphor particles 11. Further, by setting the mass% to be equal to or less than the above upper limit, the mass% of the inorganic binder 12 can be secured, so that a decrease in the strength of the fluorescent member 10 can be easily suppressed and the heat generated by the phosphor particles 11 can be suppressed. Is easy to diverge. In particular, in the optical component 100 in which the incident surface of the excitation light for exciting the phosphor particles 11 and the light extraction surface for extracting the fluorescence from the phosphor particles 11 are the same, if the mass% of the phosphor particles 11 is low, The light incident on the fluorescent member 10 may be absorbed by the metal used for the reflection film 20 without hitting the phosphor particles 11, but is absorbed by the metal by securing the mass of the phosphor particles 11 to a certain level or more. Excitation light can be reduced.

（無機バインダー１２）
無機バインダー１２は、蛍光体粒子１１を結着するものである。無機バインダー１２は、蛍光部材１０の熱膨張係数に近い熱膨張係数である材料からなることが好ましい。無機バインダー１２としては、酸化アルミニウム、酸化イットリウム等を用いることができる。 (Inorganic binder 12)
The inorganic binder 12 binds the phosphor particles 11. The inorganic binder 12 is preferably made of a material having a thermal expansion coefficient close to that of the fluorescent member 10. As the inorganic binder 12, aluminum oxide, yttrium oxide, or the like can be used.

（空隙１３）
複数の空隙１３は蛍光体粒子１１の近傍に偏在して設けられる。空隙１３は、真空、大気等により構成される。 (Void 13)
The plurality of voids 13 are provided unevenly near the phosphor particles 11. The space 13 is formed by vacuum, the atmosphere, or the like.

図５に示すように、横断面Ｘにおいて、複数の空隙１３の一部は蛍光体粒子１１に沿うように設けられていることが好ましい。これにより、蛍光体粒子１１からの光の伝搬を抑制しやすくすることができる。横断面Ｘにおいて、複数の空隙１３は蛍光体粒子１１の全周の１／２以上にわたって設けられることが好ましく、１／３以上にわたって設けられることがさらに好ましい。 As shown in FIG. 5, in the cross section X, a part of the plurality of voids 13 is preferably provided along the phosphor particles 11. Thereby, propagation of light from the phosphor particles 11 can be easily suppressed. In the cross section X, the plurality of voids 13 are preferably provided over 1/2 or more of the entire circumference of the phosphor particles 11, and more preferably provided over 1/3 or more.

空隙１３の屈折率は、無機バインダー１２の屈折率よりも低く、無機バインダー１２の屈折率は蛍光体粒子１１の屈折率よりも低いことが好ましい。これにより、空隙１３及び無機バインダー１２の界面と、無機バインダー１２及び蛍光体粒子１１の界面と、のそれぞれで励起光を全反射しやすくなるため、励起光を取り出しやすくすることができる。このとき、複数の空隙１３のうちの一部の空隙１３は、蛍光体粒子１１に直接接していることがさらに好ましい。空隙１３及び蛍光体粒子１１の屈折率差は、無機バインダー１２及び蛍光体粒子１１の屈折率差よりも大きいため、蛍光体粒子１１からの光の伝搬を抑制しやすくすることができる。 The refractive index of the void 13 is preferably lower than the refractive index of the inorganic binder 12, and the refractive index of the inorganic binder 12 is preferably lower than the refractive index of the phosphor particles 11. This makes it easier to totally reflect the excitation light at the interface between the void 13 and the inorganic binder 12 and at the interface between the inorganic binder 12 and the phosphor particles 11, thereby making it easier to extract the excitation light. At this time, it is more preferable that some of the plurality of voids 13 are in direct contact with the phosphor particles 11. Since the difference in the refractive index between the void 13 and the phosphor particles 11 is larger than the difference in the refractive index between the inorganic binder 12 and the phosphor particles 11, the propagation of light from the phosphor particles 11 can be easily suppressed.

横断面Ｘにおいて、１つの空隙１３の面積は、１つの蛍光体粒子１１の面積よりも小さいことが好ましい。面積の小さい空隙１３が複数あることにより、蛍光部材１０の強度を保ちつつ、蛍光体粒子１１からの光を反射しやすくできるためである。面積は、例えば、ＳＥＭにより蛍光体粒子１１が１０個写るスケールで撮影した写真を観察して、すべての空隙１３が、すべての蛍光体粒子１１よりも小さいことをいう。空隙１３の面積は、例えば、０．０１μｍ^２以上２μｍ^２以下とする。 In the cross section X, the area of one void 13 is preferably smaller than the area of one phosphor particle 11. This is because the presence of the plurality of voids 13 having a small area can easily reflect the light from the phosphor particles 11 while maintaining the strength of the fluorescent member 10. The area means that all the voids 13 are smaller than all the phosphor particles 11, for example, by observing a photograph taken by a SEM at a scale in which ten phosphor particles 11 appear. The area of the gap 13 is, for example, 0.01 μm ² or more and 2 μm ² or less.

（反射膜２０）
蛍光部材１０の下面には、反射膜２０が設けられている。これにより、蛍光部材１０から下面に向かう光を上方に向けて反射することができる。 (Reflection film 20)
On the lower surface of the fluorescent member 10, a reflection film 20 is provided. Accordingly, light traveling from the fluorescent member 10 to the lower surface can be reflected upward.

反射膜２０としては、金属膜及び誘電体膜の少なくとも一方を含むことができる。金属膜及び誘電体膜は、単層でも積層でもよい。金属膜としては、例えば、Ａｌ、Ａｇを用いることができる。また、誘電体膜としては、例えば、酸化ケイ素、酸化チタン、酸化アルミニウム、酸化ニオブを用いることができる。金属膜及び誘電体膜の双方を用いる場合は、蛍光部材１０の下面側から誘電体膜、金属膜をこの順に有することができる。 The reflection film 20 can include at least one of a metal film and a dielectric film. The metal film and the dielectric film may be a single layer or a stacked layer. For example, Al and Ag can be used as the metal film. Further, as the dielectric film, for example, silicon oxide, titanium oxide, aluminum oxide, and niobium oxide can be used. When both a metal film and a dielectric film are used, a dielectric film and a metal film can be provided in this order from the lower surface side of the fluorescent member 10.

（拡散防止層３０）
反射膜２０が金属膜を含む場合は、反射膜２０の下面に拡散防止層３０が設けられることが好ましい。これにより、接合部材４０が金属膜に拡散することを低減することができる、拡散防止層３０としては、例えば、Ｔｉ、Ｐｔ、Ａｕ、Ｐｄ、及びＴａの少なくも一種を含むものを用いることができる。 (Diffusion prevention layer 30)
When the reflection film 20 includes a metal film, it is preferable that the diffusion prevention layer 30 is provided on the lower surface of the reflection film 20. Thereby, the diffusion of the bonding member 40 into the metal film can be reduced. As the diffusion prevention layer 30, for example, a material containing at least one of Ti, Pt, Au, Pd, and Ta may be used. it can.

（接合部材４０）
接合部材４０は、蛍光部材１０と基部５０とを固定するものである。接合部材４０としては、例えば、ＡｕＳｎ、Ａｇ、Ａｌ、Ａｕ、などを主成分とする部材又は散乱材が入った樹脂を用いることができる。なかでも接合強度の高さから、ＡｕＳｎ等の共晶合金を用いることが好ましい。 (Joining member 40)
The joining member 40 fixes the fluorescent member 10 and the base 50. As the joining member 40, for example, a member containing AuSn, Ag, Al, Au, or the like as a main component, or a resin containing a scattering material can be used. Above all, it is preferable to use a eutectic alloy such as AuSn from the viewpoint of high bonding strength.

（基部５０）
基部５０は、蛍光部材１０よりも熱伝導率が高い材料からなり、蛍光部材１０の下面と基部５０の上面とが接続されている。これにより、蛍光部材１０からの熱を基部５０に発散しやすくなるため、蛍光体粒子１１の劣化を低減することができる。反射膜２０と基部５０とが直接接合されている場合は、接合部材４０を介することなく蛍光部材１０と基部５０とは接合される。 (Base 50)
The base 50 is made of a material having higher thermal conductivity than the fluorescent member 10, and the lower surface of the fluorescent member 10 is connected to the upper surface of the base 50. Thereby, the heat from the fluorescent member 10 is easily dissipated to the base 50, so that the deterioration of the phosphor particles 11 can be reduced. When the reflection film 20 and the base 50 are directly joined, the fluorescent member 10 and the base 50 are joined without the interposition of the joining member 40.

基部５０は、金属及び拡散反射性のセラミックスの少なくとも一方を含む。金属としては、例えば、Ｃｕ、ＣｕＭｏ、ＣｕＷを用いることができ、光拡散性のセラミックスとしては例えば酸化アルミニウム、窒化アルミニウムを用いることができる。 The base 50 includes at least one of a metal and a diffusely reflective ceramic. As the metal, for example, Cu, CuMo, CuW can be used, and as the light diffusing ceramic, for example, aluminum oxide or aluminum nitride can be used.

基部５０の厚みは、例えば、１ｍｍ以上３ｍｍ以下の範囲内にすることが好ましい。１ｍｍ以上とすることにより光学部品を取り扱いやすくなり、３ｍｍ以下とすることにより光学部品が大きくなりすぎることを防ぐことができる。 The thickness of the base 50 is preferably, for example, in the range of 1 mm or more and 3 mm or less. When the thickness is 1 mm or more, the optical component can be easily handled, and when the thickness is 3 mm or less, the optical component can be prevented from becoming too large.

（保護膜６０）
蛍光部材１０の上面には保護膜６０を設けてもよい。保護膜６０としては、例えば、酸化ケイ素、酸化ニオブを用いる。 (Protective film 60)
A protective film 60 may be provided on the upper surface of the fluorescent member 10. As the protective film 60, for example, silicon oxide or niobium oxide is used.

（光学部品１００の製造方法）
光学部品に含まれる蛍光部材１０は、例えば、以下の方法により作製することができる。 (Method of Manufacturing Optical Component 100)
The fluorescent member 10 included in the optical component can be manufactured, for example, by the following method.

蛍光部材１０の製造方法は、蛍光体粒子１１とセラミックス粒子とを混合する工程と、蛍光体粒子１１の近傍に複数の空隙１３が偏在するようにセラミックス粒子を焼結して一体にすることにより、蛍光体粒子１１と無機バインダー１２と空隙１３とを有する蛍光部材１０を得る工程と、を含む。ここではさらに、蛍光部材１０を熱処理する工程と、蛍光部材１０をスライスする工程と、蛍光部材１０の上面を研磨・研削する工程と、を含む。なお、本明細書では、説明を簡便にするため、スライス又は個片化前の蛍光部材も、個片化した後の蛍光部材もまとめて「蛍光部材１０」という。以下で、蛍光部材１０の製造方法に含まれる各工程について説明する。 The method for manufacturing the fluorescent member 10 includes a step of mixing the phosphor particles 11 and the ceramic particles, and a step of sintering and integrating the ceramic particles so that the plurality of voids 13 are unevenly distributed near the phosphor particles 11. Obtaining the fluorescent member 10 having the phosphor particles 11, the inorganic binder 12, and the voids 13. Here, the method further includes a step of heat-treating the fluorescent member 10, a step of slicing the fluorescent member 10, and a step of polishing and grinding the upper surface of the fluorescent member 10. In this specification, for the sake of simplicity, the fluorescent member before slicing or singulation and the fluorescent member after singulation are collectively referred to as “fluorescent member 10”. Hereinafter, each step included in the method for manufacturing the fluorescent member 10 will be described.

まず、蛍光体粒子１１と後に無機バインダー１２となるセラミックス粒子と、を混合する。このとき、セラミックス粒子として、蛍光体粒子１１の焼結温度よりも低い焼結温度のセラミックス粒子を用いる。これにより、蛍光体粒子１１の熱による劣化を低減しながらセラミックス粒子を焼結することができる。セラミックス粒子の粒径は、蛍光体粒子１１の粒径よりも小さいことが好ましい。これにより、蛍光体粒子１１との密着力が高くなりやすい。セラミックス粒子の粒径は、例えば、蛍光体粒子１１の１／１５以上１／２以下の範囲内にあることが好ましく、１／１２以上１／５の範囲内にあることがさらに好ましい。例えば、０．１μｍ以上２μｍ以下の範囲内とすることが好ましく、０．３μｍ以上１μｍ以下の範囲内とすることがさらに好ましい。前述の下限値以上の粒径とすることにより、安定的に作製することができ、前述の上限値以下の粒径とすることにより蛍光体粒子１１との密着力を確保することができる。 First, the phosphor particles 11 and the ceramic particles which will later become the inorganic binder 12 are mixed. At this time, ceramic particles having a sintering temperature lower than the sintering temperature of the phosphor particles 11 are used as the ceramic particles. Thereby, the ceramic particles can be sintered while reducing the deterioration of the phosphor particles 11 due to heat. The particle size of the ceramic particles is preferably smaller than the particle size of the phosphor particles 11. Thereby, the adhesion to the phosphor particles 11 is likely to be increased. The particle size of the ceramic particles is, for example, preferably in the range of 1/15 to 1/2 of the phosphor particles 11, more preferably in the range of 1/12 to 1/5. For example, the thickness is preferably in the range of 0.1 μm or more and 2 μm or less, and more preferably in the range of 0.3 μm or more and 1 μm or less. By setting the particle size to be equal to or larger than the above lower limit value, it is possible to stably manufacture, and by setting the particle size to be equal to or smaller than the above upper limit value, it is possible to secure the adhesion to the phosphor particles 11.

次に、セラミックス粒子を焼結して蛍光体粒子１１と一体にすることにより、蛍光体粒子１１と無機バインダー１２とを含む蛍光部材１０を得る。焼結する方法としては、例えば、放電プラズマ焼結（ＳｐａｒｋＰｌａｓｍａＳｉｎｔｅｒｎｉｎｇ、ＳＰＳ）法、ホットプレス（ＨＰ）法を用いることができる。このとき、蛍光部材１０の焼結密度が高くなりすぎないように、焼結温度及び時間を調整して焼結する。 Next, the fluorescent member 10 including the fluorescent particles 11 and the inorganic binder 12 is obtained by sintering the ceramic particles and integrating them with the fluorescent particles 11. As the sintering method, for example, a spark plasma sintering (SPS) method or a hot press (HP) method can be used. At this time, sintering is performed by adjusting the sintering temperature and time so that the sintering density of the fluorescent member 10 does not become too high.

セラミックス粒子を焼結する際に、セラミックス粒子は近くにある他のセラミックス粒子と結合しながら収縮する。このとき、蛍光体粒子１１から遠い領域においては、セラミックス粒子が周囲全体に満遍なくあるため、セラミックス粒子同士が結合しやすいが、蛍光体粒子１１の近傍領域においては蛍光体粒子１１の存在に起因してセラミックス粒子同士が結合しにくくなる。これにより、蛍光体粒子１１の近傍に空隙１３が偏在しやすくなると考えられる。 When sintering ceramic particles, the ceramic particles shrink while being combined with other nearby ceramic particles. At this time, in the region far from the phosphor particles 11, the ceramic particles are evenly distributed over the entire periphery, so that the ceramic particles are easily bonded to each other. This makes it difficult for the ceramic particles to bond to each other. Thereby, it is considered that the voids 13 are likely to be unevenly distributed in the vicinity of the phosphor particles 11.

ここでの焼結温度及び時間は、セラミックス粒子の表面が焼結し、且つ、蛍光体粒子１１が焼結しない温度及び時間とする。例えば、蛍光体粒子１１としてＹＡＧ系蛍光体、セラミックス粒子として酸化アルミニウムを用い、ＳＰＳ法を用いて焼結する場合は、１２００度以上１５００度以下の範囲内の温度で、その温度での保持時間は1分以上２０分以下の範囲内の時間行うことが好ましい。 Here, the sintering temperature and time are those at which the surfaces of the ceramic particles are sintered and the phosphor particles 11 are not sintered. For example, when sintering is performed by using the YPS-based phosphor as the phosphor particles 11 and the aluminum oxide as the ceramic particles and using the SPS method, and the sintering is performed at a temperature in a range of 1200 to 1500 degrees, a holding time at the temperature is used. Is preferably performed for a time within the range of 1 minute or more and 20 minutes or less.

蛍光部材１０の焼結密度は、９０％以上９８％以下の範囲とすることが好ましく、９３．５％以上９６％以下の範囲とすることがさらに好ましい。前述の下限値以上とすることにより強度を確保しやすく、前述の上限値以下とすることにより焼結密度が比較的高いものと比較して輝度の低下を低減できるとともに光束を高くすることができる。光束を高くできる理由は、空隙１３があることにより蛍光部材１０の下面に近い側まで光が入りにくくなるため反射膜の金属等による光の吸収を低減することができるためであると考えられる。焼結密度の測定方法の一例として、アルキメデスの法則を利用したものを以下に示す。まず、秤で蛍光部材１０の重さＡを求める。次に、容器に入った水に蛍光部材１０を容器の底に触れないように入れ、水中で容器及び水を除く重さＢを求める。そして、重さＡを重さＢで除算し（Ｃ）、蛍光部材１０に含まれる蛍光体粒子１１及びセラミックス粒子の真比重（Ｄ）を求めて、ＣをＤで除算することにより、蛍光部材１０の焼結密度を求めることができる。 The sintering density of the fluorescent member 10 is preferably in the range of 90% or more and 98% or less, and more preferably in the range of 93.5% or more and 96% or less. By setting the sintering density to the lower limit or more, the strength can be easily ensured, and by setting the sintering density to the upper limit or less, the decrease in luminance can be reduced and the luminous flux can be increased as compared with the case where the sintering density is relatively high. . It is considered that the reason why the luminous flux can be increased is that the presence of the gap 13 makes it difficult for light to enter the side closer to the lower surface of the fluorescent member 10, so that light absorption by the metal or the like of the reflective film can be reduced. As an example of a method for measuring the sintered density, a method utilizing Archimedes' law is shown below. First, the weight A of the fluorescent member 10 is determined using a scale. Next, the fluorescent member 10 is put into the water in the container without touching the bottom of the container, and the weight B of the water excluding the container and water is determined. Then, the weight A is divided by the weight B (C), the true specific gravity (D) of the phosphor particles 11 and the ceramic particles included in the fluorescent member 10 is obtained, and C is divided by D to obtain the fluorescent member. A sintering density of 10 can be determined.

一般的に、ＳＰＳ法やＨＰ法に用いる焼結型には炭素が含まれるため、焼結する際に酸化物に浸炭して還元反応を生じさせやく、炭素での光の吸収が起こる。そこで、本実施形態では、ＳＰＳ法等によって得られる蛍光部材１０を最終的に酸化雰囲気で熱処理している。これにより、酸化物に含有された炭素を除去して欠損した酸素を戻すことができる。 In general, since the sintering mold used in the SPS method or the HP method contains carbon, the sintering tends to cause carburization of the oxide to cause a reduction reaction, so that light is absorbed by the carbon. Therefore, in the present embodiment, the fluorescent member 10 obtained by the SPS method or the like is finally heat-treated in an oxidizing atmosphere. This makes it possible to remove the carbon contained in the oxide and return the deficient oxygen.

熱処理する工程は、１２００度以上１４５０度以下の範囲内の温度で、1時間以上４０時間以下の範囲内の時間行うことが好ましい。前述の下限値以上とすることで無機バインダー１２に含まれる酸化物に酸素を戻しやすくなり、前述の上限値以下とすることで蛍光体粒子の劣化を防ぐことができる。 The heat treatment is preferably performed at a temperature in the range of 1200 to 1450 degrees for a time in the range of 1 to 40 hours. When the content is not less than the above lower limit, oxygen can be easily returned to the oxide contained in the inorganic binder 12, and when the content is not more than the above upper limit, deterioration of the phosphor particles can be prevented.

得られた蛍光部材１０はそのまま用いてもよいが、蛍光部材１０が所望の蛍光部材１０よりも厚い場合は、ワイヤー等を用いて、所定の厚みよりも少し厚くなるように蛍光部材１０をスライスする。この厚みの蛍光部材１０が複数得られるように、複数回スライスしてもよい。更に研磨・研削により所定の厚みになるまで加工してもよい。 The obtained fluorescent member 10 may be used as it is, but when the fluorescent member 10 is thicker than a desired fluorescent member 10, the fluorescent member 10 is sliced using a wire or the like so as to be slightly thicker than a predetermined thickness. I do. Slicing may be performed a plurality of times so that a plurality of fluorescent members 10 having this thickness are obtained. Further, it may be processed by polishing / grinding to a predetermined thickness.

次に、蛍光部材１０の下面に反射膜２０及び拡散防止層３０をスパッタ法等により形成する。次に、蛍光部材１０を所望の形状となるようにブレイド等により切断して個片化する。 Next, the reflection film 20 and the diffusion prevention layer 30 are formed on the lower surface of the fluorescent member 10 by a sputtering method or the like. Next, the fluorescent member 10 is cut into individual pieces by cutting it with a blade or the like into a desired shape.

次に、蛍光部材１０の下面と基部５０の上面との間に接合部材４０を配置して蛍光部材１０と基部５０とを固着する。このとき、接合部材４０としてＡｕＳｎ箔を用いて熱圧着することが好ましい。これにより、ＡｕＳｎはんだを用いる場合に比べて接合部材４０にボイドが形成されにくくなるため、蛍光部材１０で生じる熱を発散しやすくすることができる。 Next, the joining member 40 is arranged between the lower surface of the fluorescent member 10 and the upper surface of the base 50, and the fluorescent member 10 and the base 50 are fixed. At this time, it is preferable to perform thermocompression bonding using AuSn foil as the joining member 40. This makes it difficult for voids to be formed in the joining member 40 as compared with the case where AuSn solder is used, so that the heat generated in the fluorescent member 10 can be easily dissipated.

次に、蛍光部材１０を個片化する際に付着したごみを除去するために、蛍光部材１０の上面を洗浄する。洗浄する前に、蛍光部材１０の上面に励起光を照射して蛍光部材１０からの光の色度を測定することが好ましい。例えば、蛍光体粒子１１がＹＡＧ系蛍光体であって、測定により得られた色度が所望の色度よりも黄色寄りにずれている場合は、リン酸等による酸洗浄を行う。これにより、蛍光部材１０の表面の蛍光体粒子１１が削られやすくなるため、蛍光部材１０の色度を励起光の色寄りにして所望の色度に合わせることができる。測定により得られた色度が所定の色度の範囲内である場合は、超音波洗浄により蛍光部材１０の上面を洗浄する。 Next, the upper surface of the fluorescent member 10 is cleaned in order to remove dust attached when the fluorescent member 10 is separated into individual pieces. Before washing, it is preferable to irradiate the upper surface of the fluorescent member 10 with excitation light and measure the chromaticity of light from the fluorescent member 10. For example, when the phosphor particles 11 are a YAG-based phosphor and the chromaticity obtained by the measurement is shifted from the desired chromaticity toward yellow, acid washing with phosphoric acid or the like is performed. As a result, the phosphor particles 11 on the surface of the fluorescent member 10 are easily shaved, so that the chromaticity of the fluorescent member 10 can be adjusted to a desired chromaticity by making it closer to the color of the excitation light. When the chromaticity obtained by the measurement is within a predetermined chromaticity range, the upper surface of the fluorescent member 10 is cleaned by ultrasonic cleaning.

（光源２００）
光源２００としては、例えば、発光ダイオード素子や半導体レーザ素子を含む。特に半導体レーザ素子を含むことが好ましい。半導体レーザ素子は指向性に富む光であるため、蛍光部材１０を高輝度にできる効果が顕著となるためである。半導体レーザ素子は発光ダイオード素子に比べて出力が高く蛍光部材１０が発熱しやすいため、図１に示すような反射型の光学部品１００の使用に適している。光源２００は複数の半導体レーザ素子を含んでいてもよい。また、発光装置１０００は複数の光源２００を含んでいてもよい。 (Light source 200)
The light source 200 includes, for example, a light emitting diode element and a semiconductor laser element. In particular, it is preferable to include a semiconductor laser element. This is because the semiconductor laser element emits light with high directivity, so that the effect of increasing the brightness of the fluorescent member 10 becomes significant. Since the semiconductor laser element has a higher output than the light emitting diode element and the fluorescent member 10 easily generates heat, it is suitable for use of the reflection type optical component 100 as shown in FIG. The light source 200 may include a plurality of semiconductor laser devices. Further, the light emitting device 1000 may include a plurality of light sources 200.

半導体レーザ素子又は発光ダイオード素子は可視領域の励起光を照射するものであることが好ましい。例えば、窒化物半導体を含み、発光ピーク波長が４３０ｎｍ〜４８０ｎｍの範囲にあるものを用いる。ここでは、図１に示すように、半導体レーザ素子からの励起光が蛍光部材１０の光取出し面に対して斜めから入射するように配置されている。斜めから入射する場合は、正反射方向に励起光が抜けやすくなるため、蛍光部材１０の上方から取り出される光は蛍光色の強い光になりやすい。光学部品１００によれば、空隙１３により励起光を反射させて取り出すことができるため、蛍光部材１０の上方から取り出される励起光の色を増やすことができる。 It is preferable that the semiconductor laser element or the light emitting diode element emits excitation light in the visible region. For example, a material containing a nitride semiconductor and having an emission peak wavelength in the range of 430 nm to 480 nm is used. Here, as shown in FIG. 1, the excitation light from the semiconductor laser element is arranged to be obliquely incident on the light extraction surface of the fluorescent member 10. When the light is obliquely incident, the excitation light easily escapes in the specular reflection direction, so that the light extracted from above the fluorescent member 10 is likely to be light having a strong fluorescent color. According to the optical component 100, since the excitation light can be reflected and extracted by the gap 13, the color of the excitation light extracted from above the fluorescent member 10 can be increased.

（ミラー３００）
ミラー３００は励起光を蛍光部材１０に向けて反射するものである。ミラー３００としては例えば、ＭＥＭＳ（ＭｉｃｒｏＥｌｅｃｔｒｏ-ＭｅｃｈａｎｉｃａｌＳｙｓｔｅｍｓ）を用いることができる。これにより、光を走査しながら蛍光部材１０に励起光を照射することができる。 (Mirror 300)
The mirror 300 reflects the excitation light toward the fluorescent member 10. As the mirror 300, for example, MEMS (Micro Electro-Mechanical Systems) can be used. Thus, the fluorescent member 10 can be irradiated with the excitation light while scanning the light.

（レンズ４００）
蛍光部材１０からの光はレンズ４００を通って外部に出射される。レンズ４００としては、石英ガラスを用いることができる。蛍光部材１０からの光が広がりすぎるとレンズ４００に入射する光が減るが、蛍光部材１０によれば輝度を高くすることができるため、蛍光部材１０からの光をレンズ４００に入射させやすい。 (Lens 400)
Light from the fluorescent member 10 is emitted outside through the lens 400. As the lens 400, quartz glass can be used. If the light from the fluorescent member 10 spreads too much, the light incident on the lens 400 decreases. However, according to the fluorescent member 10, the brightness can be increased, so that the light from the fluorescent member 10 can be easily incident on the lens 400.

＜実施形態２＞
図１０及び１１に示すように、実施形態２では、実施形態１とは、蛍光部材１０の下面に反射膜２０が設けられておらず、基部５０の上面に反射膜２０が設けられている点が異なる。また、蛍光部材１０の下面が少なくとも１つの凹部を有し、蛍光部材１０と基部５０とを透明接合部材４０ａで接続している点が異なる。それ以外については、実施形態１と同様である。 <Embodiment 2>
As shown in FIGS. 10 and 11, the second embodiment differs from the first embodiment in that the reflective film 20 is not provided on the lower surface of the fluorescent member 10 and the reflective film 20 is provided on the upper surface of the base 50. Are different. Further, the difference is that the lower surface of the fluorescent member 10 has at least one concave portion, and the fluorescent member 10 and the base 50 are connected by the transparent joining member 40a. Otherwise, it is the same as the first embodiment.

実施形態１のように、蛍光部材１０の下面に直接反射膜２０を成膜した場合、反射膜２０に含まれる金属が蛍光部材１０に向けてマイグレーションを起こすことがある。この場合、蛍光部材１０の内部に金属の一部が侵入して、蛍光部材１０からの光取出し量が低下してしまう。これは、蛍光部材１０に侵入した金属が、蛍光体粒子１１及び／又は無機バインダー１２を変色させてしまうためであると考えられる。また、蛍光部材１０に侵入した金属自体が光を吸収してしまうことも理由として考えられる。そこで、図１１に示すように、実施形態２に係る光学部品１００では、蛍光部材１０の下面ではなく、基部５０の上面に反射膜２０を設けるとともに、蛍光部材１０と基部５０とを透明接合部材４０ａで接続している。これにより、蛍光部材１０の下面には透明接合部材４０ａが配置されるため、透明接合部材４０ａの下方に配置される反射膜２０に含まれる金属が蛍光部材１０に向けてマイグレーションすることを抑制することができる。この結果、蛍光部材１０からの光取出し量の低下を抑制することができる。 When the reflective film 20 is formed directly on the lower surface of the fluorescent member 10 as in the first embodiment, the metal contained in the reflective film 20 may cause migration toward the fluorescent member 10. In this case, a part of the metal enters the inside of the fluorescent member 10 and the amount of light extracted from the fluorescent member 10 is reduced. It is considered that this is because the metal that has entered the fluorescent member 10 causes the phosphor particles 11 and / or the inorganic binder 12 to change color. It is also considered that the metal itself that has entered the fluorescent member 10 absorbs light. Therefore, as shown in FIG. 11, in the optical component 100 according to the second embodiment, the reflection film 20 is provided on the upper surface of the base 50 instead of the lower surface of the fluorescent member 10, and the fluorescent member 10 and the base 50 are connected to each other by a transparent bonding member. The connection is made at 40a. Thus, since the transparent bonding member 40a is disposed on the lower surface of the fluorescent member 10, the metal contained in the reflective film 20 disposed below the transparent bonding member 40a is prevented from migrating toward the fluorescent member 10. be able to. As a result, a decrease in the amount of light extracted from the fluorescent member 10 can be suppressed.

実施形態２ではさらに、蛍光部材１０の下面が少なくとも１つの凹部を有する。蛍光部材１０は複数の空隙１３を有するため、蛍光部材１０の下面をスライス、研磨及び研削の１以上を用いて所定の厚みになるように加工したときに、１つの空隙１３の一部領域が蛍光部材１０の下面近傍に配置されることがある。この場合、複数の空隙１３を有する蛍光部材１０の下面には、少なくとも１つの凹部ができる。 In the second embodiment, the lower surface of the fluorescent member 10 further has at least one concave portion. Since the fluorescent member 10 has a plurality of voids 13, when the lower surface of the fluorescent member 10 is processed to have a predetermined thickness by using one or more of slicing, polishing, and grinding, a partial region of one void 13 is formed. It may be arranged near the lower surface of the fluorescent member 10. In this case, at least one concave portion is formed on the lower surface of the fluorescent member 10 having the plurality of voids 13.

蛍光部材１０の下面が凹部を有する場合において、蛍光部材１０の下面に直接反射膜２０を成膜した場合、蛍光部材１０の下面が凹部を有さない場合と比較して、反射膜２０に含まれる金属がマイグレーションをさらに起こしやすい。これにより、蛍光部材１０の内部に金属の一部が侵入して、蛍光部材１０の上方からの光取出し量が低下してしまう。そこで、実施形態２では、蛍光部材１０の下面ではなく、基部５０の上面に反射膜２０を設けるとともに、蛍光部材１０の下面の少なくとも１つの凹部が透明接合部材４０ａで充填されるようにして、蛍光部材１０と基部５０とを透明接合部材４０ａで接続している。これにより、透明接合部材４０ａの下方に配置される反射膜２０に含まれる金属が蛍光部材１０に向けてマイグレーションすることを抑制することができる。この結果、蛍光部材１０の上方からの光取出し量の低下を抑制することができる。 In the case where the lower surface of the fluorescent member 10 has a concave portion, when the reflective film 20 is formed directly on the lower surface of the fluorescent member 10, the reflective film 20 is included in the reflective film 20 as compared with the case where the lower surface of the fluorescent member 10 has no concave portion. Metals are more prone to migration. As a result, a part of the metal enters the inside of the fluorescent member 10 and the amount of light extracted from above the fluorescent member 10 is reduced. Therefore, in the second embodiment, the reflection film 20 is provided on the upper surface of the base 50 instead of the lower surface of the fluorescent member 10, and at least one concave portion on the lower surface of the fluorescent member 10 is filled with the transparent bonding member 40a. The fluorescent member 10 and the base 50 are connected by a transparent joining member 40a. Thereby, it is possible to suppress the metal contained in the reflection film 20 disposed below the transparent bonding member 40a from migrating toward the fluorescent member 10. As a result, a decrease in the amount of light taken out from above the fluorescent member 10 can be suppressed.

透明接合部材４０ａとしては、透明樹脂（シリコーン樹脂、エポキシ樹脂）、ガラス、セラミック等を用いることができる。中でも、シリコーン樹脂を用いることが好ましい。これにより、透明接合部材４０ａで凹部を充填しやすくすることができる。また、シリコーン樹脂は、樹脂の中では耐熱性及び光透過率が比較的高いため好ましい。なお、本実施形態では透明接合部材４０ａを用いて凹部を充填しているが、透明部材を凹部に充填して、接合部材を別に設けることもできる。 As the transparent joining member 40a, a transparent resin (silicone resin, epoxy resin), glass, ceramic, or the like can be used. Especially, it is preferable to use a silicone resin. Thereby, it is possible to easily fill the concave portion with the transparent bonding member 40a. Further, silicone resin is preferable because of its relatively high heat resistance and light transmittance among resins. In the present embodiment, the concave portion is filled with the transparent bonding member 40a, but the transparent member may be filled in the concave portion and the bonding member may be separately provided.

基部５０の上面に設けられる反射膜２０としては、実施形態１において蛍光部材１０の下面に設けることができる反射膜２０と同じ材料を用いることができる。なお、基部５０が反射性を有する場合には、基部５０の上面に反射膜２０を設けずに、蛍光部材１０と基部５０とを透明接合部材４０ａで接続してもよい。ここで、反射性を有するとは、蛍光部材１０で波長変換された光の８０％以上を基部５０が反射することをいう。このような反射性を有する反射膜２０としては、例えば、Ａｇ、Ａｌ、Ａｕが挙げられる。 As the reflective film 20 provided on the upper surface of the base 50, the same material as the reflective film 20 that can be provided on the lower surface of the fluorescent member 10 in the first embodiment can be used. When the base 50 has reflectivity, the fluorescent member 10 and the base 50 may be connected by the transparent bonding member 40a without providing the reflective film 20 on the upper surface of the base 50. Here, “having reflectivity” means that the base 50 reflects 80% or more of the light whose wavelength has been converted by the fluorescent member 10. Examples of the reflective film 20 having such reflectivity include Ag, Al, and Au.

蛍光部材１０の下面の少なくとも１つの凹部の幅又は直径は、蛍光体粒子１１の粒径と同様である。 The width or diameter of at least one concave portion on the lower surface of the fluorescent member 10 is the same as the particle size of the phosphor particles 11.

蛍光部材１０の下面に透明接合部材４０ａを配置した場合、透明接合部材４０ａの一部が蛍光部材１０の側面を這い上がり、蛍光部材１０の上面に回り込むことがある。この場合、蛍光部材１０の発光効率が低下してしまう。また、蛍光部材１０の信頼性も低下してしまう。そこで、図１２に示すように、基部の上面の一部を凸部として、基部の凸部の上面に、反射膜２０と、透明接合部材４０ａと、蛍光部材１０とを下方から順に配置することができる。これにより、透明接合部材４０ａは、重力の影響により蛍光部材１０の側面よりも、基部５０の凸部の側面へ進行しやすいため、透明接合部材４０ａの蛍光部材１０の上面への回り込みを抑制することができる。 When the transparent bonding member 40 a is disposed on the lower surface of the fluorescent member 10, a part of the transparent bonding member 40 a may climb up the side surface of the fluorescent member 10 and go around the upper surface of the fluorescent member 10. In this case, the luminous efficiency of the fluorescent member 10 decreases. Further, the reliability of the fluorescent member 10 is also reduced. Therefore, as shown in FIG. 12, a part of the upper surface of the base is formed as a projection, and the reflection film 20, the transparent bonding member 40a, and the fluorescent member 10 are sequentially arranged from below on the upper surface of the projection of the base. Can be. Thereby, the transparent bonding member 40a is more likely to advance to the side surface of the convex portion of the base 50 than the side surface of the fluorescent member 10 due to the influence of gravity, so that the transparent bonding member 40a is prevented from wrapping around the upper surface of the fluorescent member 10. be able to.

＜実施例＞
以下の製造方法により光学部品を作製した。まず、粒径が５μｍのＹＡＧ蛍光体からなる蛍光体粒子１１と、粒径が０．５μｍのＡｌ_２Ｏ_３からなるセラミックス粒子と、を５０質量％ずつ準備して混合した。次に、混合したものを、１３１０℃で１０分、ＳＰＳ法により加熱してセラミックス粒子を焼結した。得られた蛍光部材１０の焼結密度は、９３．７％であった。次に得られた蛍光部材１０を市販のワイヤーソーでスライスした。そして、蛍光部材１０の上面側から厚みが１００μｍになるまで研磨及び研削を行った。 <Example>
An optical component was manufactured by the following manufacturing method. First, 50% by mass of phosphor particles 11 made of a YAG phosphor having a particle size of 5 μm and ceramic particles made of Al ₂ O ₃ having a particle size of 0.5 μm were prepared and mixed. Next, the mixture was heated at 1310 ° C. for 10 minutes by the SPS method to sinter the ceramic particles. The sintered density of the obtained fluorescent member 10 was 93.7%. Next, the obtained fluorescent member 10 was sliced with a commercially available wire saw. Then, polishing and grinding were performed from the upper surface side of the fluorescent member 10 until the thickness became 100 μm.

次に、蛍光部材１０の下面に、Ａｌ（１μｍ）の反射膜２０、及び、第１層３１がＴｉ（０．２μｍ）、第２層３２がＰｔ（０．２μｍ）、第３層３３がＡｕ（０．５μｍ）の拡散防止層３０を、蛍光部材１０の下面に近い側から順に、スパッタ法により形成した。次に、上面側から見て、長手方向の長さが１２ｍｍ、短手方向の長さが３ｍｍとなるようにブレイドにより蛍光部材を個片化した。 Next, on the lower surface of the fluorescent member 10, a reflective film 20 of Al (1 μm), the first layer 31 is Ti (0.2 μm), the second layer 32 is Pt (0.2 μm), and the third layer 33 is The diffusion prevention layer 30 of Au (0.5 μm) was formed by sputtering from the side closer to the lower surface of the fluorescent member 10. Next, when viewed from the upper surface side, the fluorescent members were singulated with a blade such that the length in the longitudinal direction was 12 mm and the length in the short direction was 3 mm.

次に、主成分がＣｕからなり、表面に２μｍのＮｉと１００ｎｍのＡｕめっきとが施された基部５０を準備した。基部５０は、上面から見て、長手方向の長さが３０ｍｍ、短手方向の長さが１２ｍｍであり、厚みが１．５ｍｍである。まず、基部５０を２５０度に加熱し、基部５０の上面と蛍光部材１０の下面との間にＡｕＳｎ箔（Ａｕ２２％、Ｓｎ７８％）を配置する。そして、ＡｕＳｎ箔を溶かしながら荷重をかけて２８０度まで加熱した。そして、２８０度到達後に２５０度まで冷却し接合を完了させた。このように熱圧着により、基部５０と蛍光部材１０と接合した。 Next, a base 50 having a main component of Cu and having a surface plated with Ni of 2 μm and Au of 100 nm was prepared. The base 50 has a length in the longitudinal direction of 30 mm, a length in the lateral direction of 12 mm, and a thickness of 1.5 mm, as viewed from above. First, the base 50 is heated to 250 degrees, and an AuSn foil (Au 22%, Sn 78%) is arranged between the upper surface of the base 50 and the lower surface of the fluorescent member 10. Then, a load was applied while melting the AuSn foil, and the foil was heated to 280 degrees. Then, after reaching 280 degrees, the temperature was cooled to 250 degrees to complete the joining. Thus, the base 50 and the fluorescent member 10 were joined by thermocompression bonding.

次に、発光ピーク波長が４５０ｎｍのレーザ光を蛍光部材１０に照射して蛍光部材１０から上方に取り出される光の色度を測定した。そして、１３０度に加熱したりん酸溶液により蛍光部材１０の表面をエッチングすることで所望の色度を得た。 Next, laser light having an emission peak wavelength of 450 nm was applied to the fluorescent member 10 to measure the chromaticity of light extracted upward from the fluorescent member 10. Then, a desired chromaticity was obtained by etching the surface of the fluorescent member 10 with a phosphoric acid solution heated to 130 degrees.

＜比較例＞
比較例は、１４５０℃で１５分焼結した以外は実施例と実質的に同様である。得られた蛍光部材の焼結密度は９９．５％であった。 <Comparative example>
The comparative example is substantially the same as the example except that it was sintered at 1450 ° C. for 15 minutes. The sintered density of the obtained fluorescent member was 99.5%.

実施例に係る蛍光部材１０について横断面ＸをＳＥＭにより観察した画像を図６に示し、比較例に係る蛍光部材について横断面をＳＥＭにより観察した画像を図７に示す。図６及び図７からわかるように、実施例に係る蛍光部材１０においては複数の空隙１３が蛍光体粒子１１の近傍に偏在しているのに対して、比較例に係る蛍光部材には空隙が存在しないことを確認した。実施例に係る蛍光部材１０は、焼結密度が高い比較例に係る蛍光部材と同様に、基部５０に蛍光部材１０を熱圧着する際に、蛍光部材１０の破損が起こらなかったことから、蛍光部材１０の強度を確保できていることが確認できた。 FIG. 6 shows an image obtained by observing the cross section X of the fluorescent member 10 according to the example by SEM, and FIG. 7 shows an image obtained by observing the cross section of the fluorescent member according to the comparative example by SEM. As can be seen from FIGS. 6 and 7, in the fluorescent member 10 according to the example, the plurality of voids 13 are unevenly distributed in the vicinity of the phosphor particles 11, whereas the voids are formed in the fluorescent member according to the comparative example. Confirmed that it does not exist. Similar to the fluorescent member according to the comparative example having a high sintering density, the fluorescent member 10 according to the example did not break the fluorescent member 10 when the fluorescent member 10 was thermocompression-bonded to the base 50. It was confirmed that the strength of the member 10 was secured.

また実施例に係る蛍光部材１０の照度を測定したデータを図８に示し、比較例に係る蛍光部材の照度を測定したデータを図９に示す。ここでは、発光ピーク波長が４４５ｎｍのレーザ光を蛍光部材の上面に対して斜め方向から、上面視で蛍光部材の長手方向に沿うように照射し（図３の左側斜め上から照射し）、上面視で最も明るく発光している箇所を短手方向に横切る線上の照度を測定した。具体的には、蛍光部材の上方から取り出される光を、ＲａｄｉａｎｔＶｉｓｉｏｎＳｙｓｔｅｍｓ社製ＰｒｏＭｅｔｒｉｃ輝度計により測定した。図８及び図９に示すように、比較例に係る蛍光部材は照度のピークから±１ｍの範囲外でも一定以上発光しているのに対して、実施例に係る蛍光部材１０は照度のピークから±１ｍの範囲内で発光している。このことから、実施例に係る蛍光部材１０では、蛍光部材１０における伝搬を抑制できていることが確認できた。また、照度のピークから±１ｍの範囲内で比較した場合に、実施例に係る蛍光部材１０では、比較例に係る蛍光部材よりも照度が高くなっている。このことから、実施例に係る蛍光部材１０は比較例に係る蛍光部材よりも高輝度であることが確認できた。 FIG. 8 shows data obtained by measuring the illuminance of the fluorescent member 10 according to the example, and FIG. 9 shows data obtained by measuring the illuminance of the fluorescent member according to the comparative example. Here, a laser beam having an emission peak wavelength of 445 nm is irradiated from an oblique direction to the upper surface of the fluorescent member along the longitudinal direction of the fluorescent member when viewed from above (emitted from the upper left side in FIG. 3). The illuminance on a line crossing the brightest spot in the lateral direction was measured. Specifically, light extracted from above the fluorescent member was measured with a ProMetric luminance meter manufactured by Radiant Vision Systems. As shown in FIGS. 8 and 9, the fluorescent member according to the comparative example emits light at a certain level even outside the range of ± 1 m from the peak of the illuminance, whereas the fluorescent member 10 according to the embodiment has the peak of the illuminance. Light is emitted within a range of ± 1 m. From this, it was confirmed that in the fluorescent member 10 according to the example, propagation in the fluorescent member 10 could be suppressed. Further, when compared within the range of ± 1 m from the peak of the illuminance, the illuminance of the fluorescent member 10 according to the example is higher than that of the fluorescent member according to the comparative example. From this, it was confirmed that the fluorescent member 10 according to the example had higher luminance than the fluorescent member according to the comparative example.

実施形態に記載の蛍光部材は、プロジェクター、照明、車両用灯具等に使用することができる。 The fluorescent member described in the embodiment can be used for a projector, lighting, a vehicle lamp, and the like.

１０…蛍光部材
１１…蛍光体粒子
１２…無機バインダー
１３…空隙
２０…反射膜
３０…拡散防止層
３１…第１層
３２…第２層
３３…第３層
４０…接合部材
４０ａ…透明接合部材
５０…基部
６０…保護膜
１００…光学部品
２００…光源
３００…ミラー
４００…レンズ
１０００…発光装置 DESCRIPTION OF SYMBOLS 10 ... Fluorescent member 11 ... Phosphor particles 12 ... Inorganic binder 13 ... Void 20 ... Reflective film 30 ... Diffusion prevention layer 31 ... First layer 32 ... Second layer 33 ... Third layer 40 ... Joining member 40a ... Transparent joining member 50 ... Base 60 Protective film 100 Optical component 200 Light source 300 Mirror 400 Lens 1000 Light emitting device

Claims

A plurality of phosphor particles, comprising an inorganic binder, a fluorescent member having an upper surface serving as a light extraction surface,
The fluorescent member includes a plurality of voids,
In one cross section that is parallel to the upper surface and crosses both the phosphor particles and the gap, the gaps are provided along at least one phosphor particle of the phosphor particles. And are unevenly distributed near the phosphor particles ,
A fluorescent member, wherein a part of the plurality of voids is in direct contact with the phosphor particles .

The fluorescent member according to claim 1, wherein the inorganic binder is a sintered body .

The refractive index of the void is lower than the refractive index of the inorganic binder,
The refractive index of the inorganic binder, the fluorescent member according to claim 1 or 2, characterized in that not lower than the refractive index of the phosphor particles.

The phosphor particles in the fluorescent member are in a range of 40% by mass or more and 70% by mass or less;
The fluorescence according to any one of claims 1 to 3 , wherein, in the fluorescent member, an incident surface of the excitation light for exciting the phosphor particles and an upper surface serving as the light extraction surface are the same surface. Element.

The phosphor particle size of the particles is fluorescent member according to any one of claims 1 to 4, characterized in that the 20μm below the range of 1 [mu] m.

The fluorescent member according to any one of claims 1 to 5 , wherein a sintering density of the fluorescent member is in a range of 90% or more and 98% or less.

The fluorescent member according to any one of claims 1 to 6 , wherein the plurality of voids are provided over one-third or more of the entire circumference of the phosphor particles.

The fluorescent member according to any one of claims 1 to 7 , wherein the fluorescent member has a lower surface located on a side opposite to the upper surface,
An optical component comprising: a base connected to a lower surface of the fluorescent member and having a higher thermal conductivity than the fluorescent member.

The optical component according to claim 8 , wherein the base includes at least one of a metal and a diffusely reflective ceramic.

The base has a reflective upper surface,
Optical component according to claim 8 or 9, wherein the lower surface of the fluorescent member and the upper surface of the base are connected by a transparent bonding member.

The optical component according to claim 10 , wherein a reflection film is formed on an upper surface of the base.

The lower surface of the fluorescent member has at least one concave portion,
The said at least one recessed part is filled with the said transparent joining member, The lower surface of the said fluorescent member and the upper surface of the said base are connected by the said transparent joining member, The Claims 10 or 11 characterized by the above-mentioned. Optical components.

Fluorescent member according to any one of claims 1 to 7, or an optical component according to any one of claims 7 to claim 11,
A semiconductor laser element that irradiates the fluorescent member with excitation light in the visible region,
The light emitting device, wherein the semiconductor laser element is arranged such that the excitation light is obliquely incident on an upper surface of the fluorescent member.

The light emitting device according to claim 13 , further comprising a mirror that reflects the excitation light from the semiconductor laser element toward an upper surface of the fluorescent member.