JP2017063115A - Light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high luminance light emitting device.SOLUTION: A light emitting device 1 has a first light source 10 having a wavelength conversion member on a first light emitting surface and a second light source 20 having a second light emitting surface facing away from the first light emitting surface. Light from the second light emitting surface is applied on the wavelength converting member.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light emitting device using a plurality of light emitting elements.

  Light-emitting devices such as LEDs (light-emitting diodes) using light-emitting elements that are semiconductors and phosphors that convert light from the light-emitting elements into light of different wavelengths are used as light sources for general lighting, street lamps, in-vehicle headlamps, etc. It's being used. In order to realize high luminance of the light emitting device, a light emitting device including a plurality of light emitting elements is used (for example, Patent Document 1).

JP 2006-339060 A

  When a plurality of light emitting elements are used, the light emitting area of the light emitting device increases accordingly, and it becomes difficult to control the light distribution with the secondary lens. In order to increase the luminance of the light emitting device, a method of increasing the current density is conceivable. However, since the risk of reliability increases according to the current density, there is a limit to the luminance that can be obtained with a single light emitting element.

In order to solve the problem, the following configuration is included.
A first light source having a wavelength conversion member on the first light emitting surface, and a second light source having a second light emitting surface facing away from the first light emitting surface, and light from the second light emitting surface is The light emitting device is irradiated with a wavelength conversion member.

  With the above configuration, the wavelength conversion member to which the light from the first light emitting element is irradiated can also be irradiated with the light from the second light source. Thereby, the excitation light that excites the wavelength conversion member is incremented, and high luminance that cannot be obtained by a single light emitting element can be obtained.

FIG. 1 is a schematic perspective view showing a light emitting device according to an embodiment. FIG. 2A is a schematic perspective view showing a first light source. 2B is a schematic cross-sectional view taken along line AA of the first light source in FIG. 2A. FIG. 3A is a schematic perspective view showing a second light source. 3B is a schematic cross-sectional view taken along line BB of the second light source in FIG. 3A. FIG. 4 is a schematic cross-sectional view in which a light emitting device according to an embodiment is partially enlarged. FIG. 5A is a schematic cross-sectional view of a partially enlarged light emitting device according to an embodiment. FIG. 5B is a schematic cross-sectional view in which a light emitting device according to an embodiment is partially enlarged. FIG. 6 is a schematic cross-sectional view in which a light emitting device according to an embodiment is partially enlarged. FIG. 7 is a schematic cross-sectional view in which a light emitting device according to an embodiment is partially enlarged.

Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. However, the light-emitting device described below is for embodying the technical idea of the present invention, and the present invention is not limited to the following unless otherwise specified. In addition, the contents described in one embodiment or example can be applied to another embodiment or example.
The size and positional relationship of the members shown in each drawing may be exaggerated for clarity of explanation. In the following description, it is assumed that the optical axis of the light emitting device is the vertical direction and light is extracted in this direction.

  The light emitting device according to the embodiment includes at least two light sources, a first light source and a second light source. The first light source includes a first light emitting surface, and the second light source includes a second light emitting surface, and each optical axis is oriented in a direction different from the light extraction direction (optical axis direction) of the light emitting device. Further, the first light emitting surface and the second light emitting surface are disposed so as to face each other with a distance therebetween. In other words, the second light emitting surface of the second light source is located in the first optical axis direction of the first light source, and the first light emitting surface of the first light source is located in the second optical axis direction of the second light source. .

  The first light source includes a first light emitting element and a wavelength conversion member provided on the first light emitting surface side of the first light emitting element. From the first light emitting surface of the first light source, mixed color light of the light from the first light emitting element and the light from the wavelength conversion member is extracted.

  The second light source includes a second light emitting element and does not include a wavelength conversion member. That is, the light from the second light emitting element is extracted as it is from the second light emitting surface of the second light source without being converted.

  Since the light from the second light source is emitted toward the first light emitting surface, the wavelength conversion member provided in the first light source is also excited by the light from the second light source. That is, the wavelength conversion member of the first light source is irradiated with both the light from the first light emitting element and the light from the second light emitting element. Finally, light in which the light from the first light emitting element, the light from the second light emitting element, and the light from the wavelength conversion member are mixed is emitted from the light extraction unit of the light emitting device to the outside. .

  In this way, the wavelength conversion member provided in one light source is irradiated not only with light from the light emitting element inside the light source but also with light from the light emitting element outside the light source, thereby allowing the wavelength of the wavelength conversion member to be irradiated. The conversion efficiency can be improved and light with higher luminance can be emitted to the outside. High brightness can be rephrased as high output. In addition, the size of the light emitting unit as the light emitting device can be reduced as compared with the case where the two light sources are arranged side by side toward the light extraction unit of the light emitting device. That is, higher density light can be extracted with a small light emitting area.

  The configurations of the first light source and the second light source can be variously selected as described later, and the angle formed by the first light emitting surface and the second light emitting surface is preferably 15 to 45 degrees. As a result, the light extraction efficiency is improved. Furthermore, it is preferable that the angle is 25 to 35 degrees because the light extraction efficiency is further improved. Note that the first light source provided with the wavelength conversion member is arranged such that the first light emitting surface is inclined (inclined upward) so that the optical axis faces the light extraction portion side of the light emitting device.

  Further, the first light emitting surface and the second light emitting surface can be arranged so that the angles formed with the optical axis of the light emitting device are inclined at the same angle. Furthermore, the distance between the center of the first light emitting surface and the light extraction portion of the light emitting device may be arranged so that the distance between the center of the second light emitting surface and the light extraction portion of the light emitting device is the same, or , They may be arranged at different distances. Further, the first light emitting surface and the second light emitting surface can be arranged in parallel.

(Embodiment 1)
An example of the light-emitting device according to Embodiment 1 is shown in FIG. An example of the first light source is shown in FIGS. 2A and 2B, and an example of the second light source is shown in FIGS. 3A and 3B. FIG. 4 shows an example of a partially enlarged view (near the light emitting surface) of the light emitting device according to the first embodiment.

  The light emitting device 1 includes a base body 30, a first light source 10, and a second light source 20. The base body 30 includes a substrate fixing portion 32 on the upper surface side and a heat radiating portion 34 on the lower surface side. The substrate fixing part 32 includes a pair of opposing fixing surfaces so that the first light source 10 and the second light source 20 can be fixed respectively. The first light source 10 and the second light source 20 are fixed to the respective fixed surfaces. Further, the cover 40 is placed so as to extend from one upper surface of the pair of substrate fixing portions 32 to the other upper surface. Specifically, a cover 40 is provided on the upper portions of the first light source 10 and the second light source 20. The cover 40 includes a through hole that is a light extraction portion 42 at the upper portion between the pair of substrate fixing portions 32, and this through hole becomes a light extraction portion (light emission portion) of the light emitting device 1. As described above, the optical axis of the light-emitting device 1 is set in the vertical direction. Specifically, the perpendicular passing through the center of the through hole is the optical axis of the light-emitting device 1.

  The first light source 10 includes a substrate 14, a first light emitting element 12a placed on the substrate 14, and a sealing member 18 disposed on the upper surface of the first light emitting element 12a. The sealing member 18 of the first light source 10 includes a wavelength conversion member. The second light source 20 includes a substrate 24 and a second light emitting element 22 placed on the substrate 24. The first light source 10 and the second light source 20 are disposed such that the first light emitting surface 10A and the second light emitting surface 20A are spaced apart from each other.

  In the first embodiment, the first light source 10 and the second light source 20 are arranged such that the first light emitting surface 10A and the second light emitting surface 20A are inclined by the same angle with respect to the optical axis of the light emitting device 1. . Specifically, the first light emitting surface 10A and the second light emitting surface 20A are disposed so as to be plane symmetric (mirror surface symmetric) with respect to the optical axis. The first light emitting surface 10A and the second light emitting surface 20A can have the same shape and the same size, but can also have different shapes and sizes. Therefore, arranging the first light emitting surface and the second light emitting surface so as to be plane-symmetric here means arranging them so that the center of the light emitting surface is a plane-symmetrical position.

  In addition, the 1st light source 10 and the 2nd light source 20 may respectively use a board | substrate with a different magnitude | size, and even if it is a board | substrate with the same magnitude | size, a light emitting element may be mounted in a different position. In other words, the entire first light source 10 and the entire second light source 20 do not need to be plane-symmetrical, and the first light-emitting surface 10A and the second light-emitting surface 20A are arranged to be plane-symmetrical to the last. That's fine.

  As described above, when the first light emitting surface 10A and the second light emitting surface 20A are arranged so as to be plane-symmetric with respect to the optical axis of the light emitting device 1, the first light emitting surface 10A and the second light emitting surface 20A are provided. The formed angle Θ is preferably 15 degrees to 45 degrees, and more preferably 25 degrees to 35 degrees.

(Embodiment 2)
An example in which a part of the light emitting device according to Embodiment 2 is enlarged is shown in FIGS. 5A and 5B. In Embodiment 2, it arrange | positions so that the height of 10 A of 1st light emission surfaces of the 1st light source 10 and 20A of 2nd light emission surfaces of the 2nd light source 20 may differ. Specifically, the light emission center position of the first light emission surface 10A is disposed above the light emission center position of the second light emission surface 20A. In other words, the first light emitting surface is disposed at a position close to the through hole (light extraction portion) 42.

  For example, as shown in FIG. 5A, the first light emitting surface 10A and the second light emitting surface 20A can be arranged such that the optical axis of the second light emitting surface 20A passes through the center of the first light emitting surface 10A. By arranging the two light sources in this manner, the light from the first light emitting surface 10A can be made difficult to hit the second light emitting surface 20A, and the light extraction efficiency from the light extraction portion (through hole) 42 of the cover 40 can be reduced. Can be improved.

  Furthermore, the distance between the first light source 10 and the second light source 20 can be arranged closer to each other as shown in FIG. 5B. Specifically, the second light emitting surface 20A can be disposed on the extension of the first light emitting surface 10A. By arranging in this way, when the light emitting device is viewed from above, the first light emitting surface 10A and the second light emitting surface 20A are arranged to be continuous. That is, when viewed from the upper side of the through hole 42 of the cover, there is no region that does not emit light between the first light emitting surface 10A and the second light emitting surface 20A. Thereby, the two light sources (the first light emitting surface and the second light emitting surface) can be visually recognized as if they were one light source.

(Embodiment 3)
An example in which a part of the light emitting device according to Embodiment 3 is enlarged is shown in FIG. The first light source 10 is arranged such that the first light emitting surface 10A is inclined with respect to the optical axis of the light emitting device. The second light source 20 is arranged so that the second light emitting surface 20A is parallel to the optical axis of the light emitting device, that is, the optical axis of the second light source 20 is perpendicular to the optical axis of the light emitting device. ing.

  By arranging in this way, the light from the second light source 20 can be made difficult to be emitted directly from the light extraction portion 42 of the light emitting device to the outside, and color unevenness can be reduced.

(Embodiment 4)
An example in which a part of the light emitting device according to Embodiment 4 is enlarged is shown in FIG. 10 A of 1st light emission surfaces of the 1st light source 10 are arrange | positioned toward the direction of a light extraction part. The second light emitting surface 20A of the second light source 20 is disposed so as to be inclined (facing the downward diagonal direction) so as to face the direction opposite to the direction of the light extraction portion of the light emitting device. By arranging in this way, the light from the second light source can be made difficult to be emitted to the outside from the light extraction portion of the light emitting device.

  In the present embodiment, the second light emitting surface 20A may be arranged to be parallel to the first light emitting surface 10A. That is, the first light emitting surface 10A facing upward and the second light emitting surface 20A facing diagonally downward are arranged in parallel with respect to the light extraction portion. With this arrangement, the light-emitting device of Embodiment 4 can efficiently emit the light from the second light source toward the first light source 10, and more light conversion by the second light source. It can be done efficiently.

  The members used for the above embodiments will be described in detail below.

(First light source)
The 1st light source provided with the 1st light emitting surface is provided with the 1st light emitting element and the wavelength conversion member. The wavelength conversion member converts light from the first light emitting element into light having a different wavelength. The wavelength converting member is provided closer to the first light emitting surface than the first light emitting element, and mixed light of the light from the first light emitting element and the light from the wavelength converting member is emitted from the first light emitting surface. The

  In addition to the first light emitting element and the wavelength conversion member, the first light source preferably includes a substrate on which these are placed. Furthermore, it is more preferable that the first light source includes a joining member that joins the substrate and the first light emitting element. The wavelength conversion member includes a phosphor and a translucent member, and is provided so as to cover the light emitting element. In addition, a conductive member (conductive bonding member, wire, or the like) that electrically connects the substrate and the light emitting element is provided. In addition, a protective element such as a Zener diode, a submount, or the like may be provided. As such a first light source, for example, a surface-mounted LED mounted on a substrate, a lamp-type LED mounted on a substrate, COB (Chip on Board), and the like can be cited. In the following description, the light emitting element and the wavelength conversion member are described separately. For example, in the case of a first light source in which a surface-mounted LED is mounted on a substrate, one LED includes the light emitting element and the wavelength conversion member. In addition to the light emitting element and the wavelength conversion member, the LED may include a covering member, a protective member, a package, or the like.

(substrate)
A board | substrate is a member for mounting a light emitting element on it, and is provided with the mounting surface of the area and shape in which a light emitting element can be mounted. As the substrate, a member with high heat dissipation is preferably used, and an insulating or conductive material can be used. Preferred materials include ceramics such as AlN, SiC, Al ₂ O ₃ , mullite, LTCC, silicone resin, silicone modified resin, epoxy resin, epoxy modified resin, phenol resin, acrylic resin, polyimide, BT resin, unsaturated polyester, etc. Or a resin such as polyphthalamide (PPA), a liquid crystal polymer (LCP), a polycarbonate resin, a thermoplastic resin such as polycyclohexane terephthalate, or a metal such as Cu, Fe, or Al. Further, a wiring capable of supplying power to the light emitting element to be mounted may be provided.

  Moreover, it is preferable that the surface of the substrate has a high reflectance with respect to light from the first light source and light from the second light source. In particular, the surface on which the light emitting element is placed preferably has a high reflectivity with respect to light from the first light source and light from the second light source. For example, the reflectance of the light from the light source can be 70% or more, 80% or more, or 90% or more. In addition to the above-described substrate having a reflectance in this range, a light reflecting member for covering the substrate surface can be provided. Examples of the material of the light reflecting member include titanium oxide, zirconium oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, zinc oxide, barium titanate, and aluminum oxide. Etc. can be used. As the conductive material, Ag, Al, or the like can be used.

  The outer shape of the substrate is preferably a flat plate shape. However, the external shape of the substrate is not limited to this, but a prismatic body such as a quadrangular prism or a triangular prism, a pyramid such as a quadrangular pyramid or a triangular pyramid, a truncated pyramid, or a combination of these, etc. And a part thereof may have a notch, unevenness, or a curved surface.

(First light emitting element)
The light emitting element includes a semiconductor light emitting element. One light emitting element may be arranged on the substrate, or two or more light emitting elements may be arranged. Only one capable of emitting light having a wavelength that can excite the wavelength conversion member may be used, or a light emitting element that emits light having a wavelength that does not substantially excite the wavelength conversion member may be used. For example, as blue and green light emitting elements, those using ZnSe or a nitride semiconductor (In _X Al _Y Ga _1- XYN, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) are used. it can.

Among these, at least a nitride-based semiconductor that can emit blue light having a dominant wavelength of 430 nm to 490 nm (In _X Al _Y Ga _1- XYN, 0 ≦ X, 0 ≦ Y, X + Y ≦ 1) Is preferably used.

Emitting element, the size (area of the first light-emitting surface side), for ^example, can be, eg 0.1mm ² ~2.0mm 2. When a plurality of light-emitting elements are provided, the total value is used.

  The light-emitting element can be used either face-up mounting or flip-chip mounting on a substrate, and is preferably flip-chip mounting. By flip-chip mounting, the light emitting element and the translucent member can be arranged without using a wire or the like.

(Wavelength conversion member)
The wavelength conversion member includes a phosphor and a translucent member that holds the phosphor, and is a member that is provided in the first light source and converts light from the first light emitting element into light of a different wavelength. The wavelength conversion member is also a member that similarly converts light from the second light emitting element of the second light source into a different wavelength.

  As the phosphor, granular materials are used. In order to fix these, the phosphor is used in combination with a light-transmitting material such as resin, glass, ceramic, and further contains a light diffusing agent. The wavelength conversion member is comprised including these.

  The wavelength conversion member is disposed so as to directly or indirectly cover the light emitting element in the first light source. For example, the wavelength converting member is potted, coated, printed, or electrically applied on the light emitting element placed on the substrate. It may be provided by a method such as wearing or spraying, or it may be provided by a method such as sticking a plate or sheet formed on a light emitting element. When the wavelength conversion member and the light emitting element are indirectly coated, a light-transmitting member (resin or the like) may be interposed therebetween, or a space may be interposed.

  For example, a description will be given of a first light source that includes an LED including a light emitting element and a wavelength conversion member and a substrate on which the LED is mounted. In the case of a configuration in which the first light emitting element is mounted on a package having a recess as an LED, potting or the like is placed in the recess of the package (frame insert resin package, ceramic package, glass epoxy package, metal package, etc.) It is preferable to provide a wavelength conversion member.

  In addition, as the LED, a package having a structure in which the side surface of the light-emitting element is covered with a light-reflective resin, a COB in which the light-emitting element is placed on a substrate, or the like can be used instead of a package having a recess.

  When a sheet or plate is used as the wavelength conversion member, the thickness thereof includes the target color tone, the characteristics of the phosphor used (emission wavelength, composition, etc.), the characteristics of the light emitting element (number, emission wavelength, composition, etc.), etc. It can be selected as appropriate according to the conditions. Further, the wavelength conversion member preferably has a uniform thickness, but may have a partially thick part or a thin part. Furthermore, when the wavelength conversion member constitutes the first light emitting surface, the surface thereof may be a convex surface, a concave surface, a prism surface, etc. in addition to a flat surface.

  The phosphor preferably has an average particle diameter (D bar) of about 2.5 to 30 μm as measured by the Fisher Sub-Seeds Sizes Number (FSSS No.) measurement method.

As the phosphor, those known in the art can be used. For example, Ce (cerium) activated Yd (yttrium aluminum garnet) phosphor, Ce activated LAG (lutetium aluminum garnet) phosphor, Eu (europium) and / or Cr (chromium) Activated nitrogen-containing calcium aluminosilicate (CaO—Al ₂ O ₃ —SiO ₂ ) -based phosphor, Eu-activated silicate ((Sr, Ba) ₂ SiO ₄ ) -based phosphor, β sialon phosphor, KSF Examples thereof include (K ₂ SiF ₆ : Mn) phosphor. A quantum dot phosphor can also be used.

  As a member which comprises a wavelength conversion member, it is preferable that a fluorescent substance and a translucent member are included. Examples of the translucent member include resins such as silicone resins, silicone-modified resins, epoxy resins, phenol resins, polycarbonate resins, acrylic resins, trimethylpentene resins, polynorbornene resins, or hybrid resins containing one or more of these resins. , Glass, ceramic and the like. Moreover, you may use what hardened only the fluorescent substance, without using a translucent material.

(Joining member)
The bonding member is a member that fixes the first light emitting element on the mounting surface of the substrate. Either a conductive bonding member or an insulating bonding member can be selected depending on the type of light emitting element to be placed. For example, when a light-emitting element in which a nitride semiconductor layer is stacked on sapphire, which is an insulating substrate, is face-up mounted (the insulating substrate side is mounted on a secondary substrate), the bonding member may be insulating or conductive. When a conductive substrate such as a SiC substrate is used, or when a light emitting element using an insulating substrate is flip-chip mounted, conduction can be achieved by using a conductive bonding member. As the insulating bonding member, an epoxy resin composition, a silicone resin composition, a polyimide resin composition, a modified resin thereof, a hybrid resin, or the like can be used. When these resins are used, a metal layer having a high reflectance such as an Al or Ag film or a dielectric reflecting film can be provided on the back surface of the light emitting element in consideration of deterioration due to light or heat from the semiconductor light emitting element. In this case, methods such as vapor deposition, sputtering, and bonding of thin films can be used. As the conductive bonding member, conductive paste such as silver, gold or palladium, solder such as Au—Sn eutectic, brazing material such as low melting point metal, bump such as Au or Cu, etc. may be used. it can. Furthermore, when using a translucent joining member among these joining members, the fluorescent member which absorbs the light from a light emitting element and light-emits the light of a different wavelength can also be contained in it.

(Other parts)
The first light source may include a wire. For example, when the light-emitting element is mounted face-up, the electrode of the first light-emitting element and the wiring of the substrate are bonded using a wire. Examples of the wire include conductive wires using metals such as copper, platinum, and aluminum and alloys containing at least those metals. In particular, it is preferable to use gold having excellent thermal resistance.

The first light source may include a light reflecting member that reflects light from the first light emitting element. For example, a light reflecting member may be provided so as to cover the side surface of the first light emitting element mounted on the substrate. The light reflecting member may be provided between the first light emitting element and the substrate. When a plurality of the first light emitting elements are provided, the light reflecting member is provided between the first light emitting element and the first light emitting element. May be. In this case, a light reflecting member may be provided so as to be in contact with the side surface of the light emitting element, or light is emitted through a translucent resin, an insulating inorganic material (for example, SiO ₂ or Al ₂ O ₃ ), or the like. It may be formed on the side surface of the element.

  The light reflecting member can be composed of a resin or glass containing inorganic particles. The resin and glass used as the base material of the light reflecting member can be variously selected according to the purpose and application, and among them, a silicone resin or an epoxy resin is preferable, and a silicone resin particularly excellent in light resistance and heat resistance is more preferable. . Since the light reflecting member can be formed by a printing method or the like, inorganic particles can be contained at a high concentration. Further, the light reflecting member may be added with silica (aerosil) or the like in order to adjust the viscosity and fluidity.

  The refractive index of the inorganic particles added to the light reflecting member is, for example, 1.8 or more, and preferably 2 or more in order to efficiently scatter light and obtain high light extraction efficiency. More preferably. The refractive index difference between the resin or glass of the base material of the light reflecting member and the inorganic particles is, for example, 0.4 or more, and is 0.7 or more in order to efficiently scatter light and obtain high light extraction efficiency. It is preferable that it is 0.9 or more. Further, the concentration of the inorganic particles is preferably 10 weight percent concentration (wt%) or more and 60 weight percent concentration or less, preferably 20 weight percent concentration or more and 50 weight percent, considering preferable light reflection characteristics and ease of formation. It is more preferable that the concentration is not more than the weight percent. The average particle diameter (median diameter) of the inorganic particles is preferably 0.08 μm or more and 10 μm or less, and more preferably 0.1 μm or more and 5 μm or less, at which a light scattering effect can be obtained with high efficiency. The inorganic particles are preferably white. Specifically, titanium oxide, zirconium oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, zinc oxide, barium titanate, aluminum oxide, or the like can be used as the inorganic particles. . Of these, titanium oxide is preferable because it is relatively stable against moisture and has a high refractive index and excellent thermal conductivity.

  The first light source may include a protective element such as a Zener diode in addition to the first light emitting element. The protection element may be placed on the substrate, or may be placed on a base that supports the substrate.

(Second light source)
The second light source includes a second light emitting element. The 2nd light source can use the member similar to a 1st light source except not providing a wavelength conversion member.

  The first light source includes a wavelength conversion member that covers the first light emitting element, whereas the second light source is covered with a sealing member that does not perform wavelength conversion. The sealing member is disposed so as to directly or indirectly cover the light emitting element. For example, potting, coating, printing, electrodeposition, spraying, etc. on the light emitting element placed on the substrate. You may provide by the method of. Specifically, in the case of a package having a recess as a substrate (frame insert resin package, ceramic package, glass epoxy package, metal package, etc.), it is preferable to provide a wavelength conversion member by potting or the like.

(Substrate)
The base is a member for integrally holding the first light source and the second light source, and a substrate fixing portion having a pair of fixing surfaces facing each other so that they can be fixed so as to be separated from each other. Prepare. As the substrate, it is preferable to use a metal excellent in heat dissipation, and examples thereof include Cu and Al. Further, for example, as shown in FIG. 1, it may be configured to be thermally continuous with the heat dissipating part provided with the fins. Moreover, it is preferable to make it difficult for a base | substrate to reflect light on the surface, for example, it is preferable to set it as dark colors, such as black.

(cover)
The cover includes a through-hole that becomes a light-emitting portion (light extraction portion) of the light-emitting device, and is fixed to the base. The size and shape of the through-hole can be appropriately selected according to the intended orientation characteristics and the like. For example, a quadrangle, a triangle, a circle, a polygon, an ellipse, or a combination of these may be used. The opening diameter (opening area) of the through hole may be an area smaller than the sum of the areas of the first light emitting surface and the second light emitting surface, a larger area, or the same size. By providing the cover in the light emitting device, it is possible to suppress the light from the second light source being directly emitted to the outside.

  Further, the inner surface of the through hole may be perpendicular to the optical axis of the light emitting device or may be inclined. Moreover, the inner surface of the through hole may have a step. The cover is preferably made of a light-shielding material that blocks light, for example, a metal plate or the like.

  The light emitting device shown in FIG. 1 shows an example in which the first light source and the second light source are each provided with a cover having a through hole on the upper surface side so that the internal configuration can be easily understood. That is, although the example provided with the area | region which is not covered with the cover is shown, it cannot be overemphasized that the further cover is provided so that light may not be emitted outside from the through-hole of the cover.

  The light emitting device of the present invention can be used for various general illuminations, scanners, projectors, in-vehicle headlamps, and the like.

DESCRIPTION OF SYMBOLS 1 ... Light-emitting device 10 ... 1st light source 10A ... 1st light emission surface 12 ... 1st light emitting element 12a ... Semiconductor laminated body 12b ... Electrode 14 ... Board | substrate 16 ... Cover member 18 ... Sealing member (wavelength conversion member)
DESCRIPTION OF SYMBOLS 20 ... 2nd light source 20A ... 2nd light emission surface 22 ... 2nd light emitting element 22a ... Semiconductor laminated body 24a ... Electrode 24 ... Substrate 26 ... Cover member 27 ... Sealing member 30 ... Base | substrate 32 ... Substrate fixing | fixed part 34 ... Radiation part 40 ... Cover 42 ... Through hole (light extraction part)

Claims (7)

A first light source comprising a wavelength conversion member on the first light emitting surface;
A second light source having a second light emitting surface that faces the first light emitting surface and is spaced apart from the first light emitting surface,
The light from the second light emitting surface is emitted to the wavelength conversion member.   The light emitting device according to claim 1, wherein the first light emitting surface and the second light emitting surface are arranged symmetrically with respect to a plane.   2. The light emitting device according to claim 1, wherein the light emitting center of the first light emitting surface is located above the second light emitting surface.   The light emitting device according to claim 1, wherein the first light emitting surface and the second light emitting surface are arranged in parallel.   The light emitting device according to claim 1, wherein the first light source and the second light source are placed on a base.   The first light source and the second light source are each provided with a cover, and the cover includes a through hole through which light from the first light source and the second light source is extracted. The light emitting device according to 1.   The light emitting device according to claim 6, wherein an opening area of the through hole is smaller than a total area of the first light emitting surface and the second light emitting surface.

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