JP2008251685A - Light-emitting device and light generating module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting module capable of efficiently taking out light. <P>SOLUTION: The light emitting device includes a first light emitting element 2a which emits, in the opposite direction from each other, excitation light L11 from first and second end faces, facing each other, a first reflecting body 1a which includes a recess consisting of a bottom surface 10a where the first light emitting element 2a is arranged and first and second side surfaces which face the first and second end faces respectively and reflect the excitation light L11. Each of the first and second side surfaces comprises, from the bottom surface 10a toward outside, concave parts 11a and 11b continuous to the bottom surface 10a, convex parts 12a and 12b continuous to the concave parts 11a and 11b, as well as concave parts 13a and 13b continuous the convex parts 12a and 12b. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light emitting device and a light emitting module including a light emitting element.

  A light emitting device (light source device) that combines a light emitting element and a phosphor has been proposed (see, for example, Patent Documents 1 to 3). The phosphor absorbs excitation light emitted from the light emitting element and emits light having a wavelength different from that of the excitation light.

  Patent Document 1 describes a light source device having a structure in which an optical fiber is used as a waveguide for excitation light and a phosphor is added to the tip of the optical fiber.

  Japanese Patent Application Laid-Open No. 2004-228561 includes a semiconductor laser element that outputs laser light, a lens that diffuses laser light from the semiconductor laser, and a phosphor that converts laser light from the diffusion lens into visible light. A light source device for use is described.

  Furthermore, Patent Document 3 proposes a light emitting device having a high light extraction efficiency, which includes a light emitting element that emits phosphor excitation light and a dispersion in which the phosphor is dispersed.

  The light emission pattern of the light emitting element is characterized by spreading perpendicular to the chip plane direction. For this reason, in the conventional method of mounting a light emitting element, mounting is performed such that one side surface of the heat sink and one light emitting end surface (light emitting surface) of the light emitting element coincide with each other or the light emitting surface protrudes. The heat sink was made not to block the excitation light emitted from. And this excitation light was used for reading and writing of the optical disk. The other light-emitting surface was coated with a high reflection so that it did not emit light or was slightly emitted and used for monitoring.

Here, the light density per light emitting surface can be reduced by using light emitted from both light emitting surfaces rather than using only light emitted from one light emitting surface. It is known that the deterioration of the light emitting element is due to the sudden deterioration of the light emitting surface, and using light emitted from both light emitting surfaces is advantageous for end face deterioration and the like. However, when the light emitting element is installed on the heat sink, the light from the light emitting surface that is not coincident with the side surface of the heat sink hits the heat sink. . Therefore, there is a problem that light cannot be extracted efficiently.
JP 2005-205195 A JP 07-282609 A JP 2006-210887 A

  The objective of this invention is providing the light-emitting device and light-emitting module which can take out light efficiently.

  According to one aspect of the present invention, (a) a first light emitting element that emits excitation light in opposite directions from the first and second end faces facing each other, and (b) a first light emitting element is disposed. A first reflector having a concave portion having a bottom surface and a first and second side surfaces respectively opposed to the first and second end surfaces and reflecting the excitation light; and (c) excited by the excitation light. (D) each of the first and second side faces outward from the bottom surface toward the outside, a concave surface portion that continues to the bottom surface, a convex surface portion that continues to the concave surface portion, and this convex surface There is provided a light emitting device having a concave portion continuous with the portion.

  According to another aspect of the present invention, (a) a first light emitting element that emits excitation light in opposite directions from the first and second end faces facing each other, and (b) a first light emitting element is disposed. And a first reflector having a recess facing the first and second end faces and having first and second side faces respectively reflecting the excitation light, and (c) a first In addition, a light emitting module is provided in which each of the second side surfaces has a concave surface portion that is continuous with the bottom surface, a convex surface portion that is continuous with the concave surface portion, and a concave surface portion that is continuous with the convex surface portion.

  According to another aspect of the present invention, (a) a heat sink, and (b) a light emitting element that is arranged on the heat sink and emits excitation light in opposite directions from the first and second end faces facing each other; C) A light emitting module is provided that includes a reflective film that is disposed on both sides of the first and second end faces on the heat sink and reflects excitation light.

  According to another aspect of the present invention, (a) a heat sink, (b) a solder layer disposed on the heat sink, and having a central portion thicker than the peripheral portion, and (c) disposed on the central portion and facing each other. There is provided a light emitting module including a light emitting element that emits excitation light in opposite directions from the first and second end faces.

  According to another aspect of the present invention, (a) a heat sink, and (b) a light emitting element that is arranged on the heat sink and emits excitation light in opposite directions from the first and second end faces facing each other; C) A light emitting module is provided that includes a low refractive index layer disposed on both sides of the first and second end faces on a heat sink, and (d) a high refractive index layer disposed on the low refractive index layer.

  ADVANTAGE OF THE INVENTION According to this invention, the light-emitting device and light-emitting module which can take out light efficiently can be provided.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  Further, the embodiments described below exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention includes the material, shape, structure, The layout is not specified as follows. The technical idea of the present invention can be variously modified within the scope of the claims.

(First embodiment)
As shown in FIG. 1, the light emitting device according to the first embodiment of the present invention is configured to emit a first excitation light L11 in opposite directions from two opposite end faces (first and second). A concave portion having a light emitting element 2a, a bottom surface 10a on which the first light emitting element 2a is disposed, and first and second side faces that face the first and second end faces that emit light and reflect excitation light, respectively. And a first reflector 1a having a light emitting module. The first side surface has, from the bottom surface 10a toward the outside, a concave surface portion 11a continuous with the bottom surface 10a, a convex surface portion 12a continuous with the concave surface portion 11a, and a concave surface portion 13a continuous with the convex surface portion 12a. The second side surface has a concave surface portion 11b continuous with the bottom surface 10a, a convex surface portion 12b continuous with the concave surface portion 11b, and a concave surface portion 13b continuous with the convex surface portion 12b from the bottom surface 10a toward the outside.

  As the first light emitting element 2a, a light emitting element having a blue to ultraviolet emission peak wavelength in a wavelength region of about 430 nm or less is used. Specifically, a semiconductor laser using aluminum gallium indium nitride (AlGaInN) which is a III-V group compound semiconductor or magnesium zinc oxide (MgZnO) which is a II-VI group compound semiconductor as a light emitting layer (active layer). A diode or a light emitting diode is used.

For example, the group III-V compound semiconductor used as the light emitting layer is a nitride semiconductor containing at least one of Al, Ga, and In. Specifically, it can be expressed as Al _x Ga _y In _(1-xy) N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ (x + y) ≦ 1), AlN, GaN, and InN A binary system of Al _x Ga _(1-x) N (0 <x <1), Al _x In _(1-x) N (0 <x <1), and Ga _y In _(1-y) N ( A ternary system of 0 <y <1) and a quaternary system including all of them are included. The emission peak wavelength in the range from ultraviolet to blue is determined based on the composition x, y of Al and Ga. Further, a part of the group III element can be substituted with boron (B), thallium (Tl), or the like. Furthermore, a part of N of the group V element can be substituted with phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), or the like.

Similarly, the II-VI group compound semiconductor used for the light emitting layer is an oxide semiconductor containing at least one of Mg and Zn. Specifically, it is expressed as Mg _z Zn _{(1-z) 2} O (0 ≦ z ≦ 1), and the emission peak wavelength in the ultraviolet region is determined based on the Mg composition z.

  FIG. 2 shows an example of an edge-emitting AlGaInN laser diode that can be used as the first light emitting element 2a. As shown in FIG. 2, the AlGaInN-based laser diode has an n-type GaN buffer layer 101, an n-type AlGaN cladding layer 102, an n-type GaN light guide layer 103, a GaInN light-emitting layer 104, a p-type on an n-type GaN substrate 100. The GaN light guide layer 105, the p-type AlGaN cladding layer 106, and the p-type GaN contact layer 107 are sequentially stacked. An insulating film 108 is provided on the ridge side surface of the p-type contact layer 107 and the surface of the p-type cladding layer 106. A p-side electrode 109 is provided on the surfaces of the p-type contact layer 107 and the insulating film 108. An n-side electrode 110 is provided on the back surface of the n-type substrate 100.

  3 and 4 show an example of an edge-emitting MgZnO laser diode that can be used as the first light emitting element 2a. In the MgZnO laser diode shown in FIG. 3, a zinc oxide (ZnO) substrate 130 is used. On the other hand, the Si substrate 140 is used in the MgZnO laser diode shown in FIG.

  The MgZnO laser diode shown in FIG. 3 includes a zinc oxide (ZnO) substrate 130, a metal reflection layer 131, a p-type MgZnO cladding layer 132, an i-type MgZnO light emitting layer 133, an n-type MgZnO cladding layer 134, and an n-type MgZnO contact layer 135. It is the structure which laminated each. An n-side electrode 136 is provided on the n-type contact layer 135. A p-side electrode 137 is provided on the substrate 130.

  The MgZnO laser diode shown in FIG. 4 has a structure in which an Si substrate 140, a ZnO buffer layer 141, a p-type MgZnO cladding layer 142, an MgZnO light emitting layer 143, and an n-type MgZnO cladding layer 144 are stacked. An n-side electrode 146 is provided on the n-type cladding layer 144 via an indium tin oxide (ITO) electrode layer 145. A p-side electrode 148 is provided on the p-type cladding layer 142 via the ITO electrode layer 147.

The first reflector 1 a shown in FIG. 1 includes a base 3 and a reflective film 4 that covers the surface of the base 3. As the substrate 3, it is desirable to use a material having excellent thermal conductivity. For example, AlN, alumina (Al ₂ O ₃ ), copper (Cu), boron nitride (BN), plastic, ceramics, diamond, and the like can be used. By using the base 3 made of such a material, heat generated by the operation of the first light emitting element 2a can be efficiently released.

  As the reflective film 4, a metal film or a dielectric multilayer film DBR having a reflectivity with respect to the excitation light L11 of about 80% or more, desirably about 90% or more can be used. In the case of a reflectance metal film, metals such as Al, gold (Au), silver (Ag), and palladium (Pd) are used. In the case of the dielectric multilayer film, oxides and nitrides such as Si, zirconium (Zr), hafnium (Hf), Al, tantalum (Ta), and titanium (Ti) are used. When the substrate 3 is a resin, the surface thereof is coated with a metal, so that the substrate 3 can be prevented from being deteriorated.

  The electrode of the first light emitting element 2a and the external power source are connected by a bonding wire (not shown). For the bonding wire, it is desirable to use a material having a small resistance value and a low visible light absorption rate. For example, an Au wire can be used. Or you may use the wire which combined noble metals, such as Pt, and Au.

  FIG. 5 shows a schematic perspective view of the light emitting device according to the first embodiment of the present invention, and FIG. 6 shows a cross-sectional view seen from the direction A of FIG. As shown in FIG.5 and FIG.6, the 2nd reflector 1b is arrange | positioned in the reflection direction of the excitation light L11 by the 1st reflector 1a. The structure of the second reflector 1b is substantially the same as the structure of the first reflector 1a shown in FIG. That is, the second reflector 1b has a bottom surface and first and second side surfaces that are continuous with the bottom surface. And each of the 1st and 2nd side surfaces of the 2nd reflector 1b goes to the outer side from the bottom face of the recessed part of the 2nd reflector 1b, and the convex surface which continues to this concave surface part. And a concave portion continuous to the convex portion.

  The 2nd light emitting element 2b is arrange | positioned at the bottom face of the recessed part which the 2nd reflector 1b has. The second light emitting element 2b emits the excitation light L21 in opposite directions from the first and second end faces facing each other. The first and second end faces of the second light emitting element 2b oppose the first and second side faces of the second reflector 1b, respectively. The first and second side surfaces of the second reflector 1b reflect the excitation light L21, respectively. Since the structure of the second light emitting element 2b is substantially the same as the structure of the first light emitting element 2a, a duplicate description is omitted. A transparent substrate 31 is disposed between the first and second reflectors 1a and 1b. In the transparent substrate 31, the reflecting mirror 41 is disposed so as to be inclined with respect to the bottom surface 10a of the concave portion of the first reflector 1a. A phosphor 42 is disposed on the reflecting mirror 41. A semipermeable membrane 33 is disposed on the surface of the transparent substrate 31.

  As the transparent base material 31, any material having high transparency of the excitation light L11, L21 and high heat resistance can be used. For example, silicone resin, epoxy resin, urea resin, fluororesin, acrylic resin, polyimide resin, etc. can be used. In particular, an epoxy resin or a silicone resin is preferable because it is easily available and easy to handle and is inexpensive. In addition to the resin, glass, a sintered body, a ceramic structure, or the like can be used.

  As the reflecting mirror 41, a metal film or dielectric multilayer film DBR having a reflectance of about 80% or more, preferably about 90% or more with respect to the excitation lights L11 and L21 can be used. In the case of a reflectance metal film, metals such as Al, Au, Ag, and Pd are used. In the case of a dielectric multilayer film, oxides and nitrides such as Si, Zr, Hf, Al, Ta, and Ti are used.

  The phosphor 42 is excited by the excitation light L11 and L21 and emits fluorescence L12 and L22. As the phosphor 42, a material that absorbs light in a wavelength region from ultraviolet to blue and emits visible light is used. For example, silicate phosphor materials, aluminate phosphor materials, nitride phosphor materials, sulfide phosphor materials, oxysulfide phosphor materials, YAG phosphor materials, borate phosphor materials Phosphor materials such as phosphate borate phosphor materials, phosphate phosphors, and halophosphate phosphor materials can be used.

(1) Silicate-based phosphor material: (Sr _(1-xyz) Ba _x Ca _y Eu _z ) ₂ Si _w O _{(2 + 2w)} (0 ≦ x <1, 0 ≦ y <1, 0. 05 ≦ z ≦ 0.2, 0.90 ≦ w ≦ 1.10)
Here, as the silicate phosphor material, a composition of x = 0.19, y = 0, z = 0.05, w = 1.0 is desirable. Silicate phosphor material replaces part of strontium (Sr), barium (Ba), and calcium (Ca) with at least one of Mg and Zn in order to stabilize the crystal structure and increase the emission intensity. May be.

Examples of silicate phosphor materials having other composition ratios include MSiO ₃ , MSiO ₄ , M ₂ SiO ₃ , M ₂ SiO ₅ , and M ₄ Si ₂ O ₈ (M is Sr, Ba, Ca, Mg, Be, Zn). And at least one element selected from Y) can be used. Further, in the silicate phosphor material, a part of Si may be replaced with germanium (Ge) in order to control the emission color (for example, (Sr _(1-xyz) Ba _x Ca _{y eu z) 2 (Si (1} -u) Ge u) O 4). Further, at least one element selected from Ti, lead (Pb), manganese (Mn), arsenic (As), Al, praseodymium (Pr), terbium (Tb), and cerium (Ce) is contained as an activator. May be.

(2) Aluminate-based phosphor material: M ₂ Al ₁₀ O ₁₇ (where M is at least one element selected from Ba, Sr, Mg, Zn, and Ca)
As an activator, at least one of europium (Eu) and Mn is included.

Examples of aluminate phosphor materials having other composition ratios include MAl ₂ O ₄ , MAl ₄ O ₁₇ , MAl ₈ O ₁₃ , MAl ₁₂ O ₁₉ , M ₂ Al ₁₀ O ₁₇ , M ₂ Al ₁₁ O ₁₉ , M ₃ Al ₅ O ₁₂ , M ₃ Al ₁₆ O ₂₇ , and M ₄ Al ₅ O ₁₂ (M is at least one element selected from Ba, Sr, Ca, Mg, Be, and Zn) can be used. Moreover, at least one element selected from Mn, dysprosium (Dy), Tb, neodymium (Nd), and Ce may be contained as an activator.

(3) Nitride-based phosphor material (mainly silicon nitride-based phosphor material): L _x Si _y N _{(2x / 3 + 4y / 3)} : Eu or L _x Si _y O _z N _{(2x / 3 + 4y / 3) -2z / 3)} : Eu (L is at least one element selected from Sr, Ca, Sr and Ca)
Although it is desirable that x = 2 and y = 5, or x = 1 and y = 7, x and y can be arbitrary values.

Specifically, Mn is added as an activator _{(Sr x Ca (1-x} )) 2 Si 5 N 8: Eu, Sr 2 Si 5 N 8: Eu, Ca 2 Si 5 N 8: Eu, Sr It is desirable to use a phosphor material such as _x Ca _(1-x) Si ₇ N ₁₀ : Eu, SrSi ₇ N ₁₀ : Eu, CaSi ₇ N ₁₀ : Eu. These phosphor materials may contain at least one element selected from Mg, Sr, Ca, Ba, Zn, B, Al, Cu, Mn, chromium (Cr), and nickel (Ni). . Moreover, at least one element selected from Ce, Pr, Tb, Nd, and lanthanum (La) may be contained as an activator.

(4) Sulfide-based phosphor material: (Zn _(1-x) Cd _x ) S: M (M is from Cu, chlorine (Cl), Ag, Al, iron (Fe), Cu, Ni, and Zn) At least one selected element, x is a numerical value satisfying 0 ≦ x ≦ 1)
Sulfur (S) may replace at least one of selenium (Se) and tellurium (Te).

(5) Oxysulfide phosphor material: (Ln _(1-x) Eu _x ) O ₂ S (Ln is at least one selected from scandium (Sc), Y, La, gadolinium (Gd), and lutetium (Lu)) Two elements, x is a numerical value satisfying 0 ≦ x ≦ 1)
At least one of Tb, Pr, Mg, Ti, Nb, Ta, Ga, samarium (Sm), and thulium (Tm) may be contained as an activator.

(6) YAG-based phosphor _{materials: (Y (1-x-} y-z) Gd x La y Sm z) 3 (Al (1-v) Ga v) 5 O 12: Ce, Eu (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ z ≦ 1.0 ≦ v ≦ 1)
At least one of Cr and Tb may be contained as an activator.

(7) Borate phosphor material: MBO ₃ : Eu (M is at least one element selected from Y, La, Gd, Lu, and In)
Tb may be contained as an activator.

Cd ₂ B ₂ O ₅ : Mn, (Ce, Gd, Tb) MgB ₅ O ₁₀ : Mn, GdMgB ₅ O ₁₀ : Ce, Tb, etc. can be used as borate phosphor materials having other composition ratios. .

(8) Phosphate borate phosphor material: 2 (M _(1-x) M ′ _x ) O.aP ₂ O ₅ .bB ₂ O ₃ (M is selected from Mg, Ca, Sr, Ba, and Zn) At least one element, M ′ is at least one element selected from Eu, Mn, Sn, Fe, and Cr, x, a, b are 0.001 ≦ x ≦ 0.5, 0 ≦ a ≦ 2, Numerical values satisfying 0 ≦ b ≦ 3 and 0.3 <(a + b))
(9) Phosphate-based phosphor: (Sr _(1-x) Ba _x ) ₃ (PO ₄ ) ₂ : Eu or (Sr _(1-x) Ba _x ) ₂ P ₂ O ₇ : Eu, Sn
Either one of Ti and Cu may be contained as an activator.

(10) Halophosphate phosphor material: (M _(1-x) Eu _x ) ₁₀ (PO ₄ ) ₆ Cl ₂ or (M _(1-x) Eu _x ) ₅ (PO ₄ ) ₃ Cl (M Is at least one element selected from Ba, Sr, Ca, Mg, and Cd, and x is a numerical value satisfying 0 ≦ x ≦ 1)
At least a part of Cl may be replaced with fluorine (F). Further, at least one of Sb and Mn may be contained as an activator.

  By appropriately selecting the above phosphor material, it can be used as a blue phosphor, a yellow phosphor, a green phosphor, a red phosphor or a white phosphor. Moreover, the fluorescent substance which light-emits an intermediate color can be formed by combining multiple types of fluorescent material. When the white phosphor is formed, phosphor materials having colors corresponding to the three primary colors of light, red, green, and blue (RGB) may be combined, or a combination of colors having a complementary color relationship such as blue and yellow may be used.

  For example, a phosphor material having a color corresponding to each of RGB is mixed with a transparent base material to form a thin film corresponding to each of RGB. By superposing these thin films, a phosphor 42 that emits white light is obtained. Further, a phosphor 42 that emits white light can be obtained by mixing RGB phosphor materials into a single transparent substrate. When obtaining the efficiency and the stability of the hue, it is desirable to arrange the phosphor multilayer films or the phosphors of one layer side by side and irradiate the light so as to obtain the desired light emission. In the case where emphasis is placed on the ease of creating the phosphor 42, a structure in which phosphors are mixed is desirable.

As the phosphor 42, for example, apatite (Sr, Ca, Ba) ₁₀ (PO 4) ₆ Cl ₂ : Eu as blue and two types of phosphors SOSE (Sr ₂ SiO ₄ : Eu) as yellow are excited to create white. You may do it. In this case, when the intensity of blue with low visibility is strong, which causes problems by exciting yellow phosphors using blue LEDs to emit white light, the white color will continue to be seen and the eyes will be damaged. There is no worry. Even when the intensity of the laser is increased, the blue phosphor 42 and the yellow phosphor 42 are increased in intensity at the same ratio, so that blue does not become extremely strong, and thus the eye is hardly damaged.

Alternatively, the phosphor 42 may be apatite as blue, SOSE as yellow-green, and CASN (CaAlSiN ₃ : Eu) as red, and the three types of phosphors 42 may be excited to create white. In this case, illumination with good color rendering is possible. A part of the phosphor 42 is transparent to the excitation lights L11 and L21, and has a function of scattering the excitation lights L11 and L21.

The semi-transmissive film 33 transmits the fluorescence L12 and L22 emitted from the phosphor 42, but absorbs the excitation light L11 and L21 emitted from the first and second light emitting elements 2a and 2b. External leakage of the excitation lights L11 and L21 can be prevented. As the semi-permeable membrane 33, for example, a layer having an oxygen deficient x of TiOx smaller than 2 can be used. The film thickness is controlled to about 300 nm so that the leakage of the excitation light L11 and L21 is 1 mW or less for all the light emitted from this apparatus. A multilayer film may be employed as the semi-transmissive film 33. For example, a structure in which three sets of SiO ₂ and ZrO reflecting the excitation lights L11 and L21 are stacked, and each thickness is excited at the refractive index of each film. It is set to be a quarter wavelength of the lights L11 and L21.

  In the light emitting device according to the embodiment of the present invention, an operating voltage is applied between the electrodes of the first and second light emitting elements 2a and 2b to oscillate excitation lights (laser lights) L11 and L21. The first and second reflectors 1a and 1b reflect the excitation lights L11 and L21 emitted from the first and second light emitting elements 2a and 2b, respectively. The excitation lights L11 and L21 are transmitted through the transparent substrate 31 and reach the phosphor 42. The phosphor 42 absorbs the excitation light L11 and L21, converts the wavelength, and emits fluorescence (visible light) L12 and L22 isotropically. The reflecting mirror 41 reflects the fluorescence L12 and L22 upward. The semi-transmissive film 33 absorbs the excitation lights L11 and L21 and emits the fluorescence L12 and L22 to the outside. Part of the excitation light L11, L21 that has not been absorbed by the phosphor 42 is reflected by the opposing first and second reflectors 1a, 1b and reenters the transparent substrate 31, or the first and second parts. The light is reflected by the end faces of the light emitting elements 2a and 2b and enters the transparent base material 31 again.

  According to the light emitting device according to the first embodiment of the present invention, the first and second end faces of the first and second light emitting elements 2a and 2b by the first and second reflectors 1a and 1b, respectively. The light emitted from can be reflected, so that light can be extracted efficiently.

  Here, when the cross sections of the first and second reflectors 1a and 1b are parabolic curved surfaces, excitation light emitted from the first and second light emitting elements 2a and 2b as shown by broken lines in FIG. The light emission irradiation pattern by L11 and L21 has a Gaussian function type distribution, the light intensity at the center becomes relatively high, and the light intensity may vary. When the phosphor is excited using this emission pattern, the difference in intensity distribution increases, and when excitation with high intensity is attempted, the conversion efficiency of the phosphor near the center decreases. On the other hand, according to the light emitting device according to the first embodiment of the present invention, the side surface of the concave portion of the first reflector 1a has the concave surface portions 11a and 11b, the convex surface portions 12a and 12b, and the concave surface portions 13a and 13b. The concave surface portions 11a and 11b, the convex surface portions 12a and 12b, and the concave surface portions 13a and 13b reflect the excitation light L11 and disperse it in different directions. Similarly to the first reflector 1a, the second reflector 1b reflects and disperses the excitation light L21 from the second light emitting element 2b in different directions by the concave surface portion, the convex surface portion, and the concave surface portion. As a result, as shown by a solid line in FIG. 7, a uniform (hat top shape) light intensity pattern can be realized.

  The first and second light emitting elements 2a and 2b, the first and second reflectors 1a and 1b, and the transparent substrate 31 are firmly bonded to each other, but the first and second light emitting elements 2a, The bonding strength between 2b and the transparent substrate 31 is lower than the bonding strength between the first and second light emitting elements 2a and 2b and the first and second reflectors 1a and 1b. For this reason, when disassembling the light emitting device, the bonding wires connecting the first and second light emitting elements 2a, 2b and the external power source are attached to the transparent base material 31 side and cut, so that the excitation lights L11, L21 are generated. Direct leakage can be prevented. Even if the light emitting device is intentionally disassembled and the first and second light emitting elements 2a and 2b are taken out, the bonding wires to the first and second light emitting elements 2a and 2b are cut, so that Since the first and second light emitting elements 2a and 2b cannot be operated, the diversion of the first and second light emitting elements 2a and 2b can be prevented.

  Further, since the first and second light emitting elements 2a and 2b are arranged at positions facing each other with the transparent base material 31 in between, the excitation light L11 emitted from one first light emitting element 2a propagates. Even in the case of the long transparent base material 31 whose strength is lowered during this time, it is possible to compensate for the reduced strength with the excitation light L21 emitted from the other second light emitting element 2b.

  Further, since the first and second reflectors 1a and 1b are arranged at positions facing each other across the transparent base material 31, a part of the excitation lights L11 and L21 that have not been absorbed by the phosphor 42 are externally provided. It is possible to return to the transparent base material 31 again without leaking, and to extract visible light safely and efficiently.

  In addition, as shown in FIG. 8, the reflective mirror 41 and the fluorescent substance 42 may be stepped. The phosphor 42 isotropically emits fluorescence by converting the wavelengths of the excitation lights L11 and L21 emitted from the first and second light emitting elements 2a and 2b. When the reflecting mirror 41 has a stepped shape, uniform light emission can be achieved by adjusting the width of the horizontal portion of the step in accordance with the intensity dependency on the radiation angle of the first and second light emitting elements 2a and 2b. Can be obtained.

  Moreover, as shown to Fig.9 (a), the planar shape of the transparent base material 31 may be circular. The cross section of the transparent base material 31 is stepped like the structure shown in FIG. A plurality of light emitting elements 2 a, 2 b, 2 c, 2 d, 2 e, 2 f, 2 g, 2 h and a first reflector 1 a are installed on the outer periphery of the transparent substrate 31. Since the periphery of the transparent substrate 31 is surrounded by the first reflector 1a, the excitation lights L11 and L21 emitted from the plurality of light emitting elements 2a, 2b, 2c, 2d, 2e, 2f, 2g, and 2h are emitted from the outer periphery. It is designed not to leak. A phosphor 42 is installed on a step-like reflecting mirror 41. As shown in FIG. 9 (a), a plurality of light emitting elements 2a, 2b, 2c, 2d, 2e, 2f, 2g, and 2h are installed on a circular transparent base material 31, thereby having a large area light emitting module and being bright. A uniform illumination is possible.

  Furthermore, as shown in FIG. 9B, a plurality of reflectors 3a, 3b, 3c, 3d, 3e, between the plurality of light emitting elements 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 3f and 3g may be arranged. The reflector 3a is disposed on the reflector 1a so as to be sandwiched between the light emitting elements 2a and 2c. The light-emitting element 2a has a first side surface facing the light-emitting end surface, and a light-emitting element 2c light-emitting end surface facing the light-emitting end surface. The first side surface of the reflector 3a has a concave surface portion 31a, a convex surface portion 32a continuous with the concave surface portion 31a, and a concave surface portion 33a continuous with the convex surface portion 32a. The second side surface of the reflector 3a has a concave surface portion 31b, a convex surface portion 32b continuous with the concave surface portion 31b, and a concave surface portion 33b continuous with the convex surface portion 32b. The reflectors 3b, 3c, 3d, 3e, 3f, and 3g have the same structure as the reflector 3a.

  Next, a method for manufacturing the light emitting device according to the first embodiment of the invention will be described. A base 3 made of AlN or the like is produced by molding, and a reflective film 4 made of Au or the like is formed on the surface of the base 3 to form the first and second reflectors 1a and 1b. The first and second light emitting elements 2a and 2b are mounted on the first and second reflectors 1a and 1b. Thereafter, the electrodes (not shown) of the first and second light emitting elements 2a and 2b are electrically connected to an external power source by bonding wires (not shown). On the other hand, the reflecting mirror 41 is prepared, and the phosphor 42 is formed on the surface of the reflecting mirror 41. The reflecting mirror 41 on which the phosphor 42 is formed is disposed between the first and second reflectors 1 a and 1 b, and the space between the first and second reflectors 1 a and 1 b is filled with the transparent base material 31. Thereafter, a semi-transmissive film 33 is formed on the upper surface of the transparent substrate 31.

(Second Embodiment)
As shown in FIG. 10, the light-emitting device according to the second embodiment of the present invention includes a first reflector 1a, a first light-emitting element 2a disposed on the first reflector 1a, A second reflector 1b disposed opposite to the first reflector 1a, a second light-emitting element 2b disposed on the second reflector 1b, and the first and second reflectors 1a and 1b. The transparent base material 31 arrange | positioned between these, and the fluorescent substance 32 distributed and arranged in the transparent base material 31 are provided. The 1st light emitting element 2a and the 1st reflector 1a, and the 2nd light emitting element 2b and the 2nd reflector 1b have a positional relationship rotated 90 degrees mutually. Note that a positional relationship in which the first light emitting element 2a and the first reflector 1a, and the second light emitting element 2b and the second reflector 1b are rotated by 90 ° is preferable, but the rotation is performed at an angle other than 90 °. It may be in a positional relationship.

  11 shows a cross-sectional view as seen from the direction B of FIG. As shown in FIG. 11, the upper surface, the lower surface, and the side surface of the transparent substrate 31 are covered with a semipermeable membrane 33. The fluorescences L13 and L14 emitted from the phosphor 32 are emitted from the upper surface, the lower surface, and the side surfaces of the semi-transmissive film 33 to the outside. Here, as shown by white circles in FIG. 12, the concentration distribution of the phosphor 32 in the transparent base material 31 is changed, and the first and second light emission are separated from the first and second reflectors 1a and 1b. The concentration is increased as it approaches the intermediate portion of the elements 2a and 2b.

  On the surface perpendicular to the direction in which the first and second light emitting elements 2a and 2b face each other, the first and second light emitting elements 2a and 2b emit excitation light L11 and L21, respectively, in different directions. The intensities of the excitation lights L11 and L21 emitted from the first and second light emitting elements 2a and 2b are scattered and absorbed by the phosphor 32 in the transparent substrate 31 and gradually weaken. For this reason, when the phosphor concentration is uniform, the light emission of the phosphor 32 becomes weaker as the distance from the first and second light emitting elements 2a and 2b increases, as shown by the black circles in FIG.

  On the other hand, according to the light emitting device according to the second embodiment of the present invention, as shown in FIG. 12, compared with the concentration in the vicinity of the first and second light emitting elements 2a and 2b, The concentration ratio of the phosphor 32 to the transparent base material 31 is changed so that the concentration increases as the distance from the first and second light emitting elements 2a and 2b and the distance between the first and second light emitting elements 2a and 2b approaches. To emit light uniformly.

  Further, the first light emitting element 2a and the first reflector 1a, and the second light emitting element 2b and the second reflector 1b are in a positional relationship rotated by 90 °, and the first and second Since the first and second light emitting elements 2a and 2b emit excitation light L11 and L21 in directions different from each other on the surface perpendicular to the direction in which the light emitting elements 2a and 2b face each other, they are arranged in the transparent base material 31. The phosphor 32 can be excited uniformly.

  As a method for manufacturing a light emitting device according to the second embodiment of the present invention, the first and second reflectors 1a and 1b are formed. The first and second light-emitting elements 2a and 2b are mounted on the first and second reflectors 1a and 1b, respectively. In the transparent base material 31, the phosphor 32 is dispersed by changing the concentration so that the concentration is low in the vicinity of the first and second light emitting elements 2 a and 2 b, and the concentration becomes higher as the distance from the first light emitting element 2 a and 2 b increases. The made transparent base material 31 is filled between the first and second reflectors 1a and 1b.

(Third embodiment)
As shown in FIG. 14, the light emitting device according to the third embodiment of the present invention includes a heat sink 51, a submount 52 disposed on the heat sink 51, and a light emitting element (semiconductor) disposed on the submount 52. Laser chip) 53 and a pair of flat reflective films 54 a and 54 b disposed on both sides of the first and second end faces of the light emitting element 53 on the submount 52. Around the light emitting element 53, although not shown, a transparent base material in which a phosphor is dispersed as described in the first and second embodiments of the present invention is disposed.

  The light-emitting element 53 is an edge-emitting light-emitting element that emits excitation light L31 in opposite directions from the first and second end faces facing each other. The reflective films 54 a and 54 b have a width wider than the widths of the first and second end faces of the light emitting element 53. The heat sink 51 needs to be large enough to obtain a sufficient heat capacity. When the submount 52 made of a material having high thermal conductivity is used between the heat sink 51 and the light emitting element 53, the heat of the light emitting element 53 can be spread in the vicinity of the light emitting element 53, and the thermal resistance is lowered. As the material of the submount 52, AlN or the like can be used. As the reflection films 54a and 54b, a dielectric multilayer film or a metal film can be used. The dielectric multilayer film is designed according to the wavelength of the laser, so that a high reflectance can be obtained.

  The excitation light L31 emitted from the light emitting element 53 is reflected by the reflection films 54a and 54b and guided to a phosphor not shown. The phosphor converts the wavelength of the excitation light L31 and outputs visible light. Other configurations are substantially the same as the configuration of the light emitting device according to the first embodiment, and thus redundant description is omitted.

  According to the light emitting device according to the third embodiment of the present invention, when the element lifetime is regulated by end face deterioration, one light emission is obtained by extracting the excitation light L31 from both light emitting surfaces of the light emitting element 53. Since the light density output from around the surface is reduced, the life can be extended.

  In addition, since the reflection films 54 a and 54 b are provided in the light emitting surface direction of the light emitting element 53, the light emitted from the light emitting element 53 is reflected by the reflection films 54 a and 54 b, so that light is not efficiently absorbed by the submount 52. Light can be extracted. Moreover, since the reflection films 54a and 54b have a width wider than the widths of the first and second end faces of the light emitting element 53, the excitation light L31 can be reflected more efficiently.

  As a manufacturing method of the light emitting device according to the third embodiment of the present invention, the light emitting element 53 is mounted at the center of the submount 52 larger than the light emitting element 53 as shown in FIG. A pair of reflective films 54 a and 54 b are selectively formed in the vicinity of the submount 52 and on the surface of the submount 52. Here, the reflective films 54 a and 54 b are formed to have a width wider than the widths of the first and second end faces of the light emitting element 53. Thereafter, if the submount 52 is attached to the heat sink 51, the light emitting device shown in FIG. 14 can be realized.

  Although the light emitting element 53 and the reflection films 54 a and 54 b are arranged on the heat sink 51 with the submount 52 interposed therebetween, the light emitting element 53 and the reflection films 54 a and 54 b may be directly arranged on the heat sink 51.

(Fourth embodiment)
As shown in FIG. 16, the light emitting device according to the fourth embodiment of the present invention includes a heat sink 51, a submount 52 disposed on the heat sink 51, and a central portion disposed on the submount 52 with a peripheral portion being a peripheral portion. A thicker solder layer 55 and an end surface light emitting element 53 disposed on the center of the solder layer 55 are provided. The solder layer 55 is formed on the entire surface of the submount 52. In the solder layer 55, the thickness of the region (center portion) in contact with the light emitting element 53 immediately below the light emitting element 53 is thicker than the thickness of the peripheral portion of the light emitting element 53. Although not shown, a transparent substrate and a phosphor as described in the first and second embodiments of the present invention are arranged around the light emitting element 53.

  The surface of the solder layer 55 has a reflectance of about 80% or more. As a material of the solder layer 55, for example, Ag-based solder containing Ag, Al, and In, containing 80 wt% or more of Ag and 15 wt% or more of In can be used. The other configuration is substantially the same as the configuration of the light emitting device according to the first embodiment of the present invention, and a duplicate description is omitted.

  In the light emitting device according to the fourth embodiment of the present invention, since the solder layer 55 immediately below the light emitting element 53 is thick, the excitation light L41 emitted from the first and second end faces of the light emitting element 53 is the solder layer. The light can be extracted efficiently without being blocked by 55.

  Furthermore, since the reflectance of the solder layer 55 is high, the excitation light L41 emitted from the light emitting element 53 is efficiently absorbed without being absorbed by the submount 52 in the first and second embodiments of the present invention. It becomes possible to guide to such a phosphor.

  As a method for manufacturing a light emitting device according to the fourth embodiment of the present invention, first, a solder layer 55 is formed on a submount 52 as shown in FIG. As shown in FIG. 18, after the temperature is raised and the solder layer 55 is melted, the light emitting element 53 is brought into contact with the solder layer 55 once. Thereafter, as shown in FIG. 19, the light emitting element 53 is pulled upward by about 4 μm, and when the solder layer 55 is pulled up by the surface tension with respect to the light emitting element 53 as shown in FIG. The layer 55 may be fixed while maintaining its shape. Thereafter, if the submount 52 is mounted on the heat sink 51, the light emitting device shown in FIG. 16 can be realized.

  Although the light emitting element 53 is disposed on the heat sink 51 with the submount 52 interposed therebetween, the light emitting element 53 may be directly disposed on the heat sink 51.

(Fifth embodiment)
As shown in FIG. 20, the light emitting device according to the fifth embodiment of the present invention includes a submount 52, a solder layer 55 formed on the submount 52, and end surface light emission disposed on the solder layer 55. Type light emitting element 53, low refractive index layers 56a and 56b disposed on submount 52, and high refractive index layers 57a and 57b disposed on low refractive index layers 56a and 56b. The horizontal level of the low refractive index layers 56 a and 56 b is higher than the horizontal level of the solder layer 55.

  As the low refractive index layers 56a and 56b, a low refractive index resin or dielectric can be used. As the high refractive index layers 57a and 57b, a high refractive index resin or dielectric can be used.

  The portion of the solder layer 55 has the same size as the end face interval of light emission within 10 μm, and the low refractive index layers 56 a and 56 b are thicker than the solder layer 55. Although not shown, a transparent substrate and a phosphor as described in the first and second embodiments of the present invention are arranged around the light emitting element 53. Other configurations are substantially the same as the configuration of the light-emitting device of the embodiment, and thus redundant description is omitted.

  According to the fifth embodiment of the present invention, the low refractive index layers 56a and 56b and the high refractive index layers 57a and 57b are stacked by adjusting the film thickness and the refractive index, thereby emitting from the end face of the light emitting element 53. It is possible to reflect the excitation light L51 and efficiently irradiate the phosphor as described in the first and second embodiments of the present invention.

  As a method for manufacturing a light emitting device according to the fifth embodiment of the present invention, low refractive index layers 56a and 56b are formed on a submount 52 as shown in FIG. Subsequently, as shown in FIG. 22, a solder layer 55 is formed on the submount 52 so that the horizontal level is lower than the low refractive index layers 56a and 56b. Thereafter, as shown in FIG. 23, the temperature is raised and the light emitting element 53 is brought into contact with the solder layer 55, and then cooled and mounted. At this time, the alignment is automatically performed by the step between the low refractive index layers 56a and 56b and the solder layer 55, so that assembly with high positional accuracy is possible. As shown in FIG. 24, the high refractive index layers 57a and 57b are formed on the low refractive index layers 56a and 56b so as to be in contact with the first and second end face portions of the light emitting element 53 that emit light.

  The light emitting element 53, the low refractive index layers 56a and 56b, the high refractive index layers 57a and 57b, and the solder layer 55 are arranged on the heat sink 51 with the submount 52 interposed therebetween. good.

(Other embodiments)
As described above, the present invention has been described according to the embodiment. However, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art.

  In the embodiment of the present invention, a light emitting device using a phosphor emitting white light is shown. However, the phosphor is not limited to white light, and a phosphor that emits visible light of another color may be used. For example, phosphors that emit visible light such as red, orange, yellow, yellow-green, green, blue-green, blue, purple, and white can be used depending on the application.

  In addition, as a use of the light-emitting device according to the embodiment of the present invention, as a general lighting fixture, a commercial lighting fixture, a backlight of a liquid crystal display device of a television or a personal computer, or a light of an automobile, a motorcycle or a bicycle, etc. Can be used.

  Further, although the edge-emitting type light emitting element has been described as the light emitting element used in the light emitting device according to the embodiment of the present invention, a surface emitting type light emitting element may be used.

  As described above, the present invention naturally includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

1 is a partial cross-sectional view of a light emitting device according to a first embodiment of the present invention. It is sectional drawing of an example of the light emitting element which concerns on the 1st Embodiment of this invention. It is sectional drawing of another example of the light emitting element which concerns on the 1st Embodiment of this invention. It is sectional drawing of another example of the light emitting element which concerns on the 1st Embodiment of this invention. 1 is a schematic perspective view of a light emitting device according to a first embodiment of the present invention. It is sectional drawing seen from the A direction of FIG. 5 of the light-emitting device which concerns on the 1st Embodiment of this invention. It is a graph showing the light emission irradiation pattern which concerns on the 1st Embodiment of this invention. It is sectional drawing of another example of the light-emitting device which concerns on the 1st Embodiment of this invention. FIG. 9A is a top view of another example of the light-emitting device according to the first embodiment of the present invention. FIG. 9B is a top view of still another example of the light emitting device according to the first embodiment of the present invention. It is a schematic perspective view of the light-emitting device concerning the 2nd Embodiment of this invention. It is sectional drawing seen from the B direction of the light-emitting device which concerns on the 2nd Embodiment of this invention. It is a graph showing the relationship between the density | concentration of the fluorescent substance of the light-emitting device which concerns on the 2nd Embodiment of this invention, and light intensity. It is a graph showing the light intensity which concerns on the 2nd Embodiment of this invention. It is a cross section of the light-emitting device which concerns on the 3rd Embodiment of this invention. It is a perspective view of the submount which concerns on the 3rd Embodiment of this invention. It is sectional drawing of the light-emitting device which concerns on the 4th Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on the 4th Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on the 4th Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on the 4th Embodiment of this invention. It is sectional drawing of the light-emitting device which concerns on the 5th Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on the 5th Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on the 5th Embodiment of this invention. It is process sectional drawing for demonstrating the manufacturing method of the light-emitting device which concerns on the 5th Embodiment of this invention.

Explanation of symbols

1a, 1b, 3a, 3b, 3c, 3d, 3e, 3f, 3g ... reflectors 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h ... light emitting elements 3 ... substrate 4 ... reflective film 10a ... bottom surface 11a, 11b, 13a, 13b, 31a, 31b, 33a, 33b ... concave surface portion 12a, 12b, 32a, 32b ... convex surface portion 31 ... transparent substrate 32 ... phosphor 33 ... transflective film 41 ... reflector 42 ... phosphor 51 ... Heat sink 52 ... Submount 53 ... Light emitting element 54a, 54b ... Reflector 54a, 54b ... Reflection film 55 ... Solder layer 56a, 56b ... Low refractive index layer 57a, 57b ... High refractive index layer 100 ... Substrate 100 ... n-type substrate 101 ... Buffer layer 102 ... Clad layer 103 ... Light guide layer 104 ... GaInN light emitting layer 105 ... Light guide layer 106 ... Clad layer 106 ... P-type clad layer 107 Contact layer 107 ... p-type contact layer 108 ... insulating film 109 ... p-side electrode 110 ... n-side electrode 130 ... substrate 131 ... metal reflective layer 132 ... cladding layer 133 ... light emitting layer 134 ... cladding layer 135 ... contact layer 135 ... n-type Contact layer 136 ... n-side electrode 137 ... p-side electrode 140 ... sapphire substrate 141 ... ZnO buffer layer 142 ... p-type cladding layer 143 ... MgZnO light emitting layer 144 ... n-type cladding layer 145 ... electrode layer 146 ... n-side electrode 147 ... ITO Electrode layer 148 ... p-side electrode

Claims (17)

A first light emitting element that emits excitation light in opposite directions from the first and second end faces facing each other;
A first reflection having a concave portion having a bottom surface on which the first light emitting element is disposed, and first and second side surfaces respectively opposed to the first and second end surfaces and reflecting the excitation light. Body,
A phosphor that emits fluorescence when excited by the excitation light,
Each of the first and second side surfaces has, from the bottom surface to the outside, a concave surface portion that continues to the bottom surface, a convex surface portion that continues to the concave surface portion, and a concave surface portion that continues to the convex surface portion. A light emitting device characterized.   2. The light emitting device according to claim 1, further comprising a second reflector arranged to reflect the excitation light in a direction in which the excitation light is reflected by the first reflector. The second reflector has a recess;
3. The light emitting device according to claim 2, further comprising a second light emitting element that emits excitation light in opposite directions from the first and second end faces facing each other on the bottom surface of the concave portion. The concave portion of the second reflector has first and second side surfaces respectively facing the first and second end faces of the second light emitting element and reflecting the excitation light;
Each of the first and second side surfaces of the second reflector is continuous from the bottom surface to the outside of the concave portion of the second reflector, and is continuous with the concave surface portion. The light emitting device according to claim 3, further comprising: a convex surface portion that has a concave surface portion that continues to the convex surface portion.   The said 1st and 2nd light emitting element emits the said excitation light in a mutually different direction on the surface perpendicular | vertical to the direction where the said 1st and 2nd light emitting element mutually opposes, respectively. The light emitting device according to 1.   The light emitting device according to claim 1, further comprising a transparent substrate that transmits the excitation light and the fluorescence.   The light emitting device according to claim 6, wherein the phosphor is dispersed in the transparent substrate.   The light emitting device according to claim 7, wherein the concentration of the phosphor increases as it approaches an intermediate portion between the first reflector and the second reflector.   The light-emitting device according to claim 1, further comprising a reflecting mirror that reflects the excitation light and the fluorescence.   The light emitting device according to claim 9, wherein the phosphor is disposed on the reflecting mirror.   11. The light emitting device according to claim 9, wherein the reflecting mirror has a flat surface or a stepped flat surface inclined with respect to the bottom surface of the first reflector.   The light emission according to claim 6, wherein a bonding strength between the electrode of the first light emitting element and the transparent substrate is smaller than a bonding strength between the first light emitting element and the first reflector. apparatus. A first light emitting element that emits excitation light in opposite directions from the first and second end faces facing each other;
A first reflection having a concave portion having a bottom surface on which the first light emitting element is disposed, and first and second side surfaces respectively opposed to the first and second end surfaces and reflecting the excitation light. With body,
Each of the first and second side surfaces has, from the bottom surface to the outside, a concave surface portion that continues to the bottom surface, a convex surface portion that continues to the concave surface portion, and a concave surface portion that continues to the convex surface portion. The light emitting module is characterized. A heat sink,
A light emitting element that is disposed on the heat sink and emits excitation light in opposite directions from the first and second end faces facing each other;
A light emitting module comprising: a reflection film disposed on both sides of the first and second end faces on the heat sink and reflecting the excitation light.   The light emitting module according to claim 14, further comprising submounts sandwiched between the heat sink and the light emitting element and between the heat sink and the reflective film. A heat sink,
A solder layer disposed on the heat sink, the central part being thicker than the peripheral part;
A light emitting module comprising: a light emitting element that is disposed on the central portion and emits excitation light in opposite directions from first and second end faces facing each other. A heat sink,
A light emitting element that is disposed on the heat sink and emits excitation light in opposite directions from the first and second end faces facing each other;
A low refractive index layer disposed on both sides of the first and second end faces on the heat sink;
A light emitting module comprising: a high refractive index layer disposed on the low refractive index layer.

Images