JP2018078327A - Light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device which enables the increase in the extraction efficiency of light emitted by a light-emitting element, the downsizing of a light-emitting device, the achievement of a high light emission efficiency, and the achievement of such light emission characteristics that the color unevenness and the brightness unevenness are both reduced.SOLUTION: A light-emitting device comprises: a coating member 30 including a light reflective material 35; a light transmissive member 20 having a light emission-side surface, and a light incident-side surface opposed to a surface of the coating member and disposed in the surface; and in a light source unit coupled to an incident region 80 surrounded by an outer reflective region 90 at the light incident-side surface of the light transmissive member, and having a part buried in the coating member, a light-emitting element 10, and a wavelength conversion member 40 coupled to an incident region side of the light-emitting element, and excited by the light-emitting element.SELECTED DRAWING: Figure 1

Description

The present invention relates to a light emitting device, and more particularly to a light emitting device including a light transmitting member and a covering member for increasing light extraction efficiency from a light emitting element.

2. Description of the Related Art In recent years, light-emitting devices equipped with semiconductor light-emitting elements such as light-emitting diodes (LEDs) and laser diodes (LDs) as light sources have been used for various lighting and display devices. In particular, since these semiconductor light emitting devices have low power consumption and long life, they are attracting attention as light sources for next-generation illumination that can be replaced with fluorescent lamps, and further improvements in light emission output and light emission efficiency are required.

For example, in the light-emitting device proposed in Patent Document 1, a light-emitting element chip that is an LED is flip-chip mounted on the bottom of a storage recess provided in a package that is a mounting substrate.
In addition, an incident surface of the light extraction increasing member having the shape of a plano-convex lens is optically coupled to the emission surface of the light emitting element chip. The light extraction increasing member has an intermediate refractive index between the sapphire substrate of the light emitting element chip and air. The exit surface of the light extraction increasing member is a spherical surface, and at all positions on the exit surface, light is emitted within a cone whose normal is the center line and whose critical angle is the angle between the center line and the generatrix. The output surface of the element chip is included. According to this configuration, substantially no total reflection occurs on the exit surface of the light extraction increasing member, so that light can be extracted from the light extraction increasing member without causing attenuation or extinction of light due to multiple reflection. Therefore, it is said that the light use efficiency can be increased.

JP 2006-351809 A JP 2007-019096 A JP 2006-037097 A JP 2006-352061 A JP 2002-305328 A JP-A-10-151794

However, in the light-emitting device described in Patent Document 1, light emitted from the light-emitting element chip to the side passes through the sealing resin and propagates through the sealing resin or package. Absorbed and attenuated. Further, since the sealing resin is also optically coupled to the incident surface of the light extraction increasing member, the light emitting area on the incident surface is substantially increased, and the light component reflected on the emission surface of the light extraction increasing member is increased. For these reasons, the light emitted from the light emitting element chip cannot be sufficiently extracted to the outside, and it is difficult to further reduce the size of the apparatus while maintaining the light extraction efficiency.

Conventionally, LED light is assumed as a light source, and the extraction efficiency is increased. The extracted LED light is wavelength-converted by a separately provided phosphor or the like.
Therefore, the light extraction efficiency of the wavelength converted light as the emitted light of the light emitting device and the LED light added thereto are reduced due to light scattering and absorption between the separated LED light source unit and the wavelength converting unit. The structure of the device is such that the directivity of the emitted light is reduced, the color unevenness and the luminance unevenness are increased, or the emission characteristics of the emitted light of the device are insufficient. There may be. Furthermore, in such a separation structure of the light source and the conversion unit, there is a side where it is difficult to reduce the size of the entire apparatus.

The present invention has been made in view of the above problems, and its purpose is to improve the extraction efficiency of light emitted from the light emitting element, to be able to reduce the size, to increase the light emission efficiency, color unevenness, and luminance unevenness. It is an object of the present invention to provide a light-emitting device capable of achieving light emission characteristics with suppressed light emission.

The light emitting device according to the present invention can achieve the above object by the following configurations (1) to (13).
(1) A light-transmitting member having a light-reflecting material-containing covering member, a light-emitting surface, and a light-incident-side surface disposed in the surface, facing the surface of the covering member; On the light incident side surface of the light transmitting member, a light source element coupled to an incident region surrounded by an outer reflective region and partially embedded in the covering member, a light emitting element, and the incident region side of the light emitting element And a wavelength conversion member that is coupled to and excited by the light emitting element.
(2) The light transmitting member has a convex curved surface on the light emitting side and a surface in which at least the reflective region on the light incident side is substantially flat, and a cross-sectional width of the incident region is not more than half of the surface on the light incident side. The light emitting device according to (1) above.
(3) A light-transmitting member having a light-reflecting material-containing covering member, a light-emitting surface having a convex curved surface, and a light-incident-side surface disposed in the surface facing the surface of the covering member And a light source side surface of the light transmissive member coupled to an inner incident region surrounded by a reflection region of a substantially flat surface, and a light source part partially embedded in the covering member is provided, A light emitting device provided in a light source unit, wherein a cross-sectional width of the incident region is not more than half of the light incident side surface.
(4) The light emitting device according to (3), further including a wavelength conversion member coupled to the light source unit on the incident region side of the light emitting element and excited by the light emitting element.
(5) The wavelength conversion member is a plate-like body having first and second main surfaces facing each other, and a plurality of the light emitting elements are bonded to the second main surface, and the incident region The light-emitting device according to any one of (1), (2), and (4), wherein the first main surface is bonded to the light-emitting device.
(6) The light-emitting device according to any one of (1) to (5), wherein the reflection region is provided on a surface of the light transmission member that is separated from a surface of the covering member.
(7) The light-emitting device includes a light-transmitting adhesive that adheres the light-incident-side surface of the light-transmitting member and the surface of the covering member, and the incident region and the reflective region are the light-transmitting adhesive. The light emitting device according to any one of (1) to (6), which is provided at an interface with the agent.
(8) Any of the above (1) to (5), wherein the light transmitting member is provided on the light source unit and on the surface of the covering member, and the reflection region is an interface between the light transmitting member and the covering member. Or one
The light-emitting device as described in one.
(9) The light emitting device according to (8), wherein the incident region protrudes toward the light emitting side from the reflective region.
(10) The surface shape on the light emitting side of the light transmitting member is a spherical shape described in (1) to (9) above.
The light emitting device according to any one of the above.
(11) The light emitting device includes a mounting board on which the light emitting element is mounted, and the light emitting element is electrically connected to the mounting board on a mounting surface side facing the surface on the incident region side. The light emitting device according to any one of (1) to (10) above.
(12) The light source unit of the light emitting device includes a wavelength conversion member that is coupled to the incident region side surface of the light emitting element and is excited by the light emitting element, and the covering member extends from the incident region to the light source unit. The light-emitting device according to (11), wherein the light-emitting device is provided so as to cover a side surface of the mounting substrate and extend to the surface of the mounting substrate.
(13) The light emitting device according to (12), wherein the covering member is provided in contact with side surfaces of the light emitting element and the wavelength conversion member.

The present invention covers the light emitting element of the light source unit and the wavelength conversion unit coupled thereto with the light-reflective coating member, and extracts the light emitted from the light source of the light emitting element or the composite light source in one direction,
That is, the light source is one light emitting surface, the light emitting window of the light emitting device is a specific area on one surface, and the light transmitting member that includes the window is joined and covered with the covering member, thereby The light extraction efficiency can be significantly improved, and light emission characteristics with suppressed color and luminance unevenness can be obtained. In particular, it is possible to efficiently extract light by being coupled to the window portion in a part of the light transmitting member and reflecting the light component reflected from the inner surface of the light transmitting member in the other region by the covering member. That is, even if the light transmitting member has a large amount of light component propagating in the member, the extraction efficiency can be increased. Therefore, even if the light transmitting member occupying a relatively large area and volume is reduced and the device is downsized. The deterioration of characteristics can be suppressed. Moreover, since it is set as the said composite light source, the light source part can be made small and this also contributes to size reduction of an apparatus.

It is the schematic sectional drawing (a) of the light-emitting device which concerns on one embodiment of this invention, and its schematic top view (b). FIG. 2 is a schematic cross-sectional view illustrating the periphery of the light source unit of the light emitting device of FIG. It is a schematic sectional drawing (A)-(D) which shows the light-emitting device of each calculation model concerning this invention. It is a graph which shows the relationship between the ratio of the diameter of the light transmissive member and the diameter of an incident area | region in each calculation model of this invention, and light extraction efficiency. It is a schematic sectional drawing of the light emitting element which concerns on one embodiment of this invention. It is typical sectional drawing (A)-(D) which shows the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. It is the schematic sectional drawing (a) of the light-emitting device which concerns on one embodiment of this invention, and the schematic sectional drawing (b) explaining the light source part periphery. It is a schematic sectional drawing explaining the light source part periphery of the light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing (a)-(c) of each light-emitting device which concerns on one embodiment of this invention. It is a schematic sectional drawing of the light-emitting device which concerns on one embodiment of this invention. It is a graph which shows the relationship between the light transmissive member and luminous efficiency in the light-emitting device which concerns on this invention.

Hereinafter, embodiments of the invention will be described with reference to the drawings as appropriate. However, the light-emitting element / device described below is for embodying the technical idea of the present invention, and the present invention is not limited to the following. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the components described below are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and the plurality of elements are shared by one member, and conversely, the function of one member is constituted by a plurality of members. It can also be realized by sharing. Similarly, each embodiment described below can be applied by appropriately combining the components and the like unless otherwise specified.

(Embodiment 1)
1 and 2 are schematic views of the light-emitting device 100 according to Embodiment 1 of the present invention, and FIG.
FIG. 2 is a schematic cross-sectional view taken along line AA of FIG. 1B in a schematic top view, and FIG. 2 is a schematic cross-sectional view around the light source unit. The light emitting device 100 shown in FIGS. 1 and 2 mainly includes a light emitting element 10, a light transmitting member 20, a covering member 30, a wavelength conversion member 40, and a mounting substrate 50. The substrate 50 includes a frame 55 and a wiring 51 on which a plurality of (two in the figure) light emitting elements 10 are flip-chip mounted. The wavelength conversion member 40 has a plate-like first and second surfaces facing each other, and the second surface is bonded to the back surface of each light emitting element 10. And
The covering member 30 containing the light reflecting material 35 is filled inside the frame body 55, and the light emitting element 10 and the wavelength conversion member 40 of the light source unit are covered with the covering member 30 with the first surface exposed. .
The covering member 30 continuously covers the side surface, a part of the second surface, and further the side surface of the light emitting element 10. Thereby, the light emitted from the light emitting element 10 and / or the wavelength conversion member 40 is reflected and guided to the light emission side by the light reflective coating member 30 and is taken out from the first surface of the wavelength conversion member 40. Thus, a surface-emitting light source having the first surface as a main light extraction window, that is, a light-emitting surface is obtained. The shape and size of the first surface can be used as a light source. On this light source, a light transmitting member 20 as an optical element for the light source is joined to a light incident region 80 in a partial region on the light incident side. .

FIG. 2 is a schematic cross-sectional view for explaining the periphery of the light source unit of the light emitting device according to the first embodiment. As shown in FIG. 2, the light transmitting member 20 has a wavelength conversion member 4 on the surface on the light incident side.
The light emitting side surface 21 that is a light emitting surface of the light emitting device is provided on a part of the covering member 30 that includes the first surface of 0 and surrounds the outside of the first surface. Have. The surface on the light incident side is opposed to the first surface of the wavelength conversion member 40, the incident region 80 where the light from the light emitting element 10 and / or the wavelength conversion member 40 is incident, and the surface of the outer covering member 30 And a reflective region 90 facing the surface. The incident region 80 increases the light extraction efficiency from the first surface of the wavelength conversion member 40, and reflects the light of the light transmitting member 20 in the reflection region 90 as shown in FIGS. . Here, as shown in the figure, the light transmitting member 20 is a hemispherical lens, and the center thereof is substantially the center of the incident region on the surface of the light source section as shown in FIG. 3A, that is, includes a light emitting surface 21 having a convex curved surface. It is an optical element. At this time, in the cross section perpendicular to the first surface of the wavelength conversion member 40, the diameter (cross-sectional width) L of the light source portion and the incident region 80 is less than or equal to half the radius of curvature r (= R / 2) of the light transmitting member 20. L ≦ (R / 2) / 2 is preferable. Part of the light incident from the incident region 80 is emitted to the outside from the light emitting side surface 21, and the remaining light components are reflected to the light incident side by the inner surface of the light emitting side surface 21 to become return light. This return light is directly
Alternatively, many of them reach the reflection region 90 while repeating multiple reflection on the inner surface of the light transmitting member 20. The return light incident on the reflection region 90 is reflected on the surface of the light-reflective coating member 30, thereby changing the angle of incidence on the light-emitting side surface 21 of the light transmission member 20 and facilitating transmission to the outside. Is done. Here, as will be described later, it is preferable that the covering member is a light-transmitting member provided with a light-reflective material because the irregular reflection effect on the surface is enhanced and the loss of light is small.

In addition, as described above, light incident on the light transmitting member 20 from the light emitting element 10 or the light source unit including the light emitting element 10 and the wavelength conversion member 40 is applied to the light reflective coating member 30 as one of the light source units. The light is hardly incident on the light transmission member 20 directly from the reflection region 90, and the light emission region becomes a point light source with respect to the light transmission member 20. You can get closer. As a result, it is possible to reduce the light reflection on the light emitting side surface 21 of the light transmitting member of the optical element having a convex curved surface, and thus to reduce the size and thickness of the entire apparatus while maintaining high light extraction efficiency. It becomes. As described above, in the light emitting device of the present invention, the incident region 8 in which the light source part is coupled with high efficiency in the light transmitting member 20 on the light incident side surface of the light transmitting member 20.
0, a reflection region 90 for reflecting the light component in the light transmitting member toward the light emitting side surface 21,
Due to the different actions, the light extraction efficiency can be remarkably improved corresponding to various shapes of the light-emitting side surface 21 of the light transmitting member 20.

In particular, in the first embodiment, the light incident side surface of the light transmitting member 20 is directly on the light source part, that is, the first surface of the wavelength conversion member 40 and the outer surface of the covering member 30. In other words, the incident region 80 is provided at the interface with the first surface, and the reflection region 90 is provided at the interface with the surface of the covering member 30. Therefore, the return light reaching the reflection region 90 can be reflected or scattered on the surface of the light-reflective coating member 30 and transmitted through the light emitting side surface 21 to be taken out of the apparatus. In particular, as described later, when the covering member is a light-transmitting member containing a light-reflective material, for example, a light-transmitting resin, interface reflection with the light-transmitting member can be performed on the surface of the covering member. The light incident on the inside is reflected and scattered by the light reflective material, so that the effect of the reflection region 90 is enhanced and the light emitting device is excellent in light emission characteristics. In the light emitting device 100 according to the first embodiment, after the surface-emitting light source unit is manufactured as described later,
Further, the light transmitting member 20 can be produced by directly joining and molding by various molding techniques, and is the most excellent in mass productivity as compared with the light emitting devices of other embodiments described later.

Moreover, it is preferable that the incident area | region 80 protrudes in the light emission side from the reflective area | region 90 so that it may show in figure. As a result, the surface of the covering member 30 is not shielded from light, and as shown in the drawing, the reflective region 90 is inclined from the reflective region toward the projecting incident region 80, that is, an inclined surface that reflects outward. Light emission to the side of the light transmitting member 20 by the reflection region 90, that is, a high angle component from the light emitting device is increased, and a wide orientation is obtained.

(Optical element and light source)
The relationship between the light transmitting member 20, that is, the diameter W of the optical element, the radius of curvature r of the convex curved surface, and the diameter L of the incident region 80 will be described in detail below. FIG. 3 is a schematic sectional view showing the structure of each light emitting device of the theoretical calculation model examined here. Light-emitting device 1 shown in FIG.
10 is provided with a light source portion 16 of a rectangular parallelepiped (plate shape) having a square of one side length L and a thickness of 100 μm. In addition, the light source unit exposes only the upper surface thereof, covers the side surface and the bottom surface thereof with the covering member 31, and the reflectance of the covering member 31 is 100%. A hemispherical light-transmitting member 20a having a diameter R and having a center of curvature at the center of the upper surface of the light source unit indicated by a black circle in the drawing is provided on the surface of the light source unit and the covering member on the same surface. The light transmitting member has a diameter R and a diameter W of 4 mm (curvature radius 2 mm).
And the refractive index is 1.537. The light emitting device 110 is assumed to be the light emitting device 100 of the first embodiment. In addition, the light-emitting device 120 illustrated in FIG. 3B includes a light-transmitting member 20b.
And the surface of the covering member 32 are the same as those of the light emitting device 110 described above except that a gap 86 is provided and both surfaces are separated from each other. More specifically, there is an inclined surface 94 that faces the flat surface (reflection region) of the light transmission member 20 b outside the light source unit 16 and is inclined downward from the upper surface of the light source unit, and the refractive index of air in the gap 86. Is 1.000. The light emitting device 120 is assumed to be a light emitting device 200 according to a second embodiment to be described later.

The light emitting device 130 shown in FIG. 3C is the same as the light emitting device 110 except that the light source unit 16 is provided on the surface of the covering member 33, and the light source unit is embedded in the light transmitting member 20c. The center of curvature is covered by the light source 16 as indicated by the black circle in the figure.
Located in the center of the bottom of the. Further, in the light emitting device 140 shown in FIG. 3D, the surface on which the light transmitting member is provided includes the covering member 34 and the base 35 having a low reflectance on the outside thereof, and the light transmitting member 20d is changed. Other than that, the light emitting device 110 is the same as the light emitting device 110. More specifically, the covering member 34 has a reflectance of 100% as in the other devices, is a square having a side of 2.7 mm when viewed from above, and the base material 35 has a reflectance of 90%. The entire region of the light transmitting member is configured. The light transmission member 20d is a spherical surface having a curvature radius of 3 mm and having a center of curvature at a position 2 mm away from the center of the upper surface of the light source unit, and the diameter W is about 4.472 mm. Therefore, in the light emitting device 140, on the light incident side surface of the light transmitting member, the reflectance of 90% is applied to the region having the reflectance of 100% by the coating member 34 outside the incident region, and further to the substrate 35 outside thereof.
The surface on the light source side is a hemispherical flat surface.

Based on each of the light emitting devices 110, 120, 130, and 140 described above, the radius of curvature r (
R / 2) or diameter (cross-sectional width) W and the ratio (L / R, L / W) of the diameter (cross-sectional width) L of the incident region;
The relationship with the light extraction efficiency is analyzed by theoretical calculation for each model. FIG. 4 shows the analysis results. Models A to C are the devices 110 to 130, model AD is a model in which the covering member 31 of the device 110 is replaced with the covering member 34 and the base material 35 of the device 140, and models DD and DD. -W is the above-described device 140 and L / W ratio of the device 140, and models DA and DA-W are the above-described device 140 in which the covering member 34 and the base material 35 are replaced with the covering member 31 of the device 110 and L Each of them is shown in the / W ratio, and the diameter L of the light source unit 16 is changed. As shown in FIG. 4, in models A to C and AD, DD-W, DA-W light emitting devices, the L / R ratio (
When the models DD-W and DA-W have an L / W ratio (greater than 0.5), the light extraction efficiency begins to decrease, and this is particularly noticeable in the models A to C and AD. This indicates that in the range of 0.5 or less, the light source unit can achieve light extraction efficiency close to that of a point light source with respect to the light emitting side surface of the light-transmitting member having a hemispherical surface and a convex curved surface. Further, when the models A to C are compared with each other, the models A and B are significantly less reduced in light extraction efficiency even in the region where the L / R is larger than the model C of the comparative example. It can be seen that a structure in which a part is covered with a light-reflective coating member has an advantage in downsizing the apparatus while maintaining high luminous efficiency. Further, in the model AD of the comparative example, even in a region where the light source is small, the efficiency is lower than that of the models A to C, and the L / R decreases rapidly when 0.5 or more. However, it is necessary to make the light transmitting member sufficiently large, and it is necessary to increase the size of the apparatus for high efficiency.

Furthermore, the light extraction efficiency of the models DA and DD using the light transmitting member 20d of the light emitting device 140 is the same as that of the models A to C and AD using the light transmitting members 20a to 20c of the other light emitting devices 110 to 130.
The initial and maximum values are significantly lower than From the viewpoint of light extraction efficiency, it is most preferable that the shape of the light transmission side surface of the light transmitting member is a hemispherical surface, but the apparatus is enlarged. On the other hand, in the light emitting device 140 (model DA, DD) of the hemispherical flat member 20d,
Although the light reflection component on the inner surface of the light transmitting member 20d increases and the efficiency decreases, it is excellent in reducing the size and thickness of the apparatus. Even if the models DA and DD are compared, the model DD (device 140) of the comparative example
It can be seen that the efficiency of the model DA tends to be superior to that of the model DA, and that the present invention can realize a highly efficient device even in the downsizing and thinning. Further, like the light emitting device 140, the light transmitting member 20.
The models AD and DD having the low reflectance region 35 on the outer edge of the surface on the light incident side are comparative examples. In such a region, for example, members in the apparatus lower than the covering member such as the substrate 50 and the wiring 51 are exposed. Assuming a structure to be made. Therefore, in this model, the light reflection at the inner surface increases due to the downsizing of the device and the increase in the area of the light source part, the amount of light reaching the low-reflectance region constituting the outer edge in this ring shape increases, and the light extraction efficiency is further increased. Will be reduced. The light transmitting member of the present invention is a flat shape from a hemispherical surface, a flat convex surface with a changed curvature, or FIG. 9B.
(C) Even if it has various optical lens shapes and has a structure in which the internal reflection of the light transmitting member increases, it has high luminous efficiency, and the device is downsized and thin while maintaining high efficiency. Can be

  Next, each component and structure of the light emitting device of the present invention will be described in detail below.

(Light emitting element)
As the light-emitting element 10, a known element, specifically, a semiconductor light-emitting element can be used. In particular, a GaN-based semiconductor is preferable because it can emit visible light or ultraviolet light having a short wavelength that can excite a fluorescent substance efficiently. The specific emission peak wavelength is 240 nm or more and 560 nm or less, preferably 38
It is 0 nm or more and 470 nm or less. In addition, ZnSe, InGaAs, Al
A light emitting element of an InGaP semiconductor may be used.

(Light emitting element structure)
As illustrated in FIG. 5, the light emitting device structure 11 including a semiconductor layer has at least the first conductivity type (n
Type) layer 2 and a second conductivity type (p-type) layer 3, and a structure having an active layer 3 between them is preferable. Further, the electrode structure has both the first conductivity type and the second conductivity type electrodes 6 on one main surface side.
7 is preferable, but a counter electrode structure in which electrodes are provided to face each main surface of the semiconductor layer may be used. As for the mounting form of the light emitting element 10, for example, in the same surface side electrode structure, flip chip mounting in which the electrode forming surface is the mounting surface and the substrate 1 side facing it is the main emitting surface is the emitting surface and the light transmitting member. 20 is preferable in terms of optical connection. In addition,
Mounting where the electrode forming surface side is the main emission surface, and a translucent member and a wavelength conversion member are coupled thereon,
Face-up mounting, translucent member with wiring structure, flip chip mounting on wavelength conversion member, and connection with light transmitting member and mounting substrate with above counter electrode structure, preferably light emitting element and translucent It is preferable to mount the embodiment in which the member and the wavelength conversion member are not provided with wiring and electrodes. In addition,
The growth substrate 1 of the semiconductor layer 11 may be removed when the light emitting element structure is not formed, and a support substrate such as a conductive substrate or another light-transmissive member is added to the semiconductor layer from which the growth substrate has been removed. A structure in which substrates are bonded can also be used. A translucent member and a wavelength conversion member 20 can also be used for this support substrate, and the semiconductor layer is bonded and adhered by a light transmissive member such as glass or resin.
It may be an element having a structure covered and supported. The removal of the growth substrate can be performed by peeling, polishing, or LLO (Laser Lift Off) by mounting or holding the growth substrate on a support, device, or submount, for example. In addition, the light emitting element 10 can have a light reflecting structure. Specifically, of the two main surfaces of the semiconductor layer 11 facing each other, the other main surface facing the light extraction side (emission surface side) is formed. The light reflection side (the lower side in FIG. 1) can be provided, and a light reflection structure can be provided in the semiconductor layer on this light reflection side or in an electrode. As an example of the light reflecting structure, a structure in which a multilayer reflective layer is provided in the semiconductor layer, or an electrode having a highly light reflective metal film such as Ag or Al or a dielectric multilayer film, or a reflective layer is provided on the semiconductor layer. There is a structure.

(Nitride semiconductor light emitting device)
As an example of the light emitting element 10, in the nitride semiconductor light emitting element 10 of FIG. 5, an n-type semiconductor layer that is the first nitride semiconductor layer 2 and an active layer 3 are formed on the C-plane sapphire substrate that is the growth substrate 1. The light emitting layer and the p-type semiconductor layer which is the second nitride semiconductor layer 4 are epitaxially grown in this order. Then, a part of the n-type layer 2 is exposed to form an n-type pad electrode, which is the first electrode 7, and a light-transmitting conductive layer 5 such as ITO is formed on almost the entire surface of the p-type layer 4. 6, a p-type pad electrode is formed. Further, the protective film 8 is n-type and the surfaces of the p-type pad electrodes 6 and 7 are exposed,
It is provided so as to cover the semiconductor layer. Note that the n-type pad electrode 7 may be formed through a light-transmitting conductive layer as in the p-type. The growth substrate 1 includes C-plane sapphire, R-plane and A-plane, an insulating substrate such as spinel (MgAl ₂ O ₄ ), silicon carbide (6H, 4H, 3C), Si, Zn
There are semiconductor conductive substrates such as S, ZnO, GaAs, GaN, and AlN. Examples of the nitride semiconductor, other general formula _{In x Al y Ga 1-xy} N (0 ≦ x, 0 ≦ y, x + y ≦ 1), B
Or, P and As may be mixed. The n-type and p-type semiconductor layers 2 and 4 are not particularly limited to a single layer or multiple layers, and the active layer 3 preferably has a single (SQW) or multiple quantum well structure (MQW). As an example of the blue light emitting element structure 11, an n-type semiconductor layer such as Si-doped GaN is formed on a sapphire substrate via a nitride semiconductor underlayer such as a buffer layer, for example, a low-temperature growth thin film GaN and a GaN layer. N-type contact layer and GaN / InGaN n-type multilayer film layer, followed by InGaN / GaN MQW active layer, and p-type semiconductor layer, for example, Mg-doped InGaN / AlGaN p-type multilayer film layer And a p-type contact layer of Mg-doped GaN.

(Wavelength conversion member)
The light emitting device 100 of FIG. 1 includes a wavelength conversion member 40 that is excited by light from the light emitting element 10 in the light source unit and can convert at least a part of the incident light. The light source unit may be constituted by a light emitting element or a structure to which a light transmissive member bonded thereto is added, and a wavelength conversion member is preferably used as the light transmissive member. In this specification, even if it is simply described as a wavelength conversion member, it can be replaced with a translucent member when not depending on the wavelength conversion function. Thereby, secondary light having a wavelength different from the emission wavelength of the light emitting element 10 is obtained by exciting the primary light emitted from the light emitting element 10 in the light source unit by the wavelength conversion member 40, and the primary light, It becomes a composite light source that can realize outgoing light having a desired hue by mixing the wavelength-converted secondary light. In addition to this, a light source unit that emits almost all of the secondary light or its secondary light excited by the primary light, such as converted light (monochromatic or mixed color light) of an ultraviolet light emitting LED, The light-emitting device provided with this may be sufficient.

Moreover, the wavelength conversion member 40 in FIG. 1 is configured to include the light emitting element 10 in a plan view from the first surface side. In other words, as shown in FIG. 1, the side surface of the wavelength conversion member 40 protrudes outward from the side surface of the light emitting element 10. Thereby, since the emitted light from the light emitting element 10 is directly coupled by the light receiving surface wider than the upper surface of the light emitting element 10, the loss of the light beam is small. In addition, the protrusion amount of the side surface of the wavelength conversion member 40 with respect to the side surface of the light emitting element 10 is, for example, 3% or more and 30% or less, specifically 5% or more and 15%, as compared with the dimension of the light emitting element 10.
It is as follows. As an example, in the light emitting device of Example 2 below, the end of the wavelength conversion member 40 protrudes with a width of about 50 μm.

The shape of the wavelength conversion member 40 is not particularly limited, but in the first embodiment, it is a plate-like body, has good coupling efficiency with the emission surface of the planar light emitting element 10, and can be easily aligned so as to be substantially parallel to each other. preferable. In addition, by making the thickness substantially constant, it is possible to stabilize the color mixture ratio and suppress color unevenness in the incident region 80 on the surface of the light source unit. In addition, it is easy to bond a plurality of light emitting elements 10 to one wavelength conversion member 40, and the distribution of luminance and chromaticity on the emission surface of the light source section depends on the arrangement of the light emitting elements, but can be suppressed. In addition, the thickness of the wavelength conversion member 40 is preferably 10 μm or more and 500 μm or less, and more preferably 50 μm or more and 300 μm or less in terms of luminous efficiency and chromaticity adjustment. Further, the number of the light emitting elements 10 to be bonded to one light transmissive member and the wavelength conversion member 40 is not particularly limited.
This is preferable because the amount of luminous flux can be increased and the luminance of the light emitted from the light source can be increased. In the case of a plurality of arrangements, arrangement in a single row, arrangement at lattice positions at equal intervals, and the like can be mentioned.

Here, as a material of the translucent member used for the light source part and serving as a base material of the wavelength conversion member 40, the same material as the covering member 30 described below can be used, for example, resin, glass,
An inorganic substance can be used. Further, the following phosphor molded body and crystal body may be used. Specifically, examples of the wavelength conversion member 40 include a glass plate provided with the wavelength conversion member, a phosphor crystal or a single crystal body having a phase thereof, a polycrystal body, an amorphous body, and a ceramic body. In addition, a sintered body, an aggregate, a porous body of phosphor crystal particles and a light-transmitting member to be added as appropriate, and a light-transmitting member such as a light-transmitting resin mixed or impregnated, or It is comprised from the light transmissive member containing a fluorescent substance particle, for example, the molded object etc. of translucent resin.

The wavelength conversion member can be suitably combined with a blue light emitting element to emit white light. As a typical phosphor used for the wavelength conversion member, a YAG phosphor (yttrium, aluminum, Garnet) and LAG-based phosphors (lutetium / aluminum / garnet), particularly in the case of high brightness and long time use (R
e _1-x Sm _x ) ₃ (Al _1-y Ga _y ) ₅ O ₁₂ : Ce (0 ≦ x <1, 0 ≦ y ≦ 1, where Re is
It is at least one element selected from the group consisting of Y, Gd, La, and Lu. Etc.) are preferred. YAG, LAG, BAM, BAM: Mn, (Zn, Cd) Zn: Cu, CC
A, SCA, SCESN, SESN, CESN, CASBN and CaAlSiN ₃ : Eu
A phosphor containing at least one selected from the group consisting of can be used. The wavelength conversion member is
In addition to the light-transmitting member, for example, the light-transmitting member may be provided between the light-transmitting member and the light-emitting element, or between the light-emitting element and the covering member in the adhesive interposed therebetween. The red component is increased using a nitride-based phosphor having yellow to red light emission, etc., and the lighting and light bulb color LE with a high average color rendering index Ra
D etc. can also be realized. Specifically, by adjusting the amount of phosphors having different chromaticity points on the CIE chromaticity diagram according to the light emission wavelength of the light emitting device, the phosphors are connected with each other on the chromaticity diagram. Any point can be made to emit light. In addition, nitride phosphors, oxynitride phosphors, and silicate phosphors that convert near-ultraviolet to visible light into a yellow to red region can be used. For example, L ₂ SiO ₄ : Eu (L is an alkaline earth metal), especially (Sr _x Mae _1-x ) ₂ Si
O ₄ : Eu (Mae is an alkaline earth metal such as Ca or Ba). As nitride-based phosphors and oxynitride (oxynitride) phosphors, Sr—Ca—Si—N: Eu
Ca—Si—N: Eu, Sr—Si—N: Eu, Sr—Ca—Si—O—N: Eu, C
a-Si—O—N: Eu, Sr—Si—O—N: Eu, and the like. As the alkaline earth silicon nitride phosphor, the general formula LSi ₂ O ₂ N ₂ : Eu, the general formula L _x Si _y N _{(2 / 3x + 4 / 3y)} : Eu or L _x Si _{y Oz} N _{(2 / 3x + 4 / 3y-2 / 3z)} : Eu (L is Sr, Ca, Sr or Ca) It is represented by

(Coating member)
As shown in FIG. 1, the covering member 30 covers a part of the light source part and the surface of the light transmitting member, specifically covers the light source part including at least the light emitting element, and additionally transmits light. It extends to the incident side surface of the member and covers it. Furthermore, a part of the wavelength conversion member 40 in the light source unit, specifically, the side surface thereof is covered, and the light source unit surface exposed from the surface becomes the exit surface and enters the light transmitting member. The base material of the covering member 30 is a resin material, and further has good translucency, and it is preferable to use a silicone resin composition, a modified silicone resin composition, etc., but an epoxy resin composition, a modified epoxy resin composition, etc. An insulating resin composition having translucency such as an acrylic resin composition can be used. Further, a sealing member having excellent weather resistance, such as a hybrid resin containing at least one of these resins, can be used, and such a translucent resin is suitable for coating a desired region in the present invention and molding it. In addition, inorganic materials having excellent light resistance such as glass and silica gel can also be used. Furthermore, it is preferable that the covering member 30 is a resin molded body having high heat resistance because it can cope with heat generation of the light emitting element of the light source unit and the wavelength conversion member 40. In the first embodiment, a silicone resin is used as a resin that is a base material constituting the covering member 30. Silicone resins are excellent in heat resistance, water repellency, and electrical insulation, and have the advantage of being resistant to deterioration over time. Further, the surface of the covering member 30 can be formed into a desired shape, for example, the shape of an inclined surface or curved surface shown in the figure, so that the function and effect of the reflection region can be improved, directivity and color distribution can be controlled, and light can be condensed. The light emission characteristics of the device can be controlled by appropriately combining with the optical function of the light transmitting member.

The covering member 30 contains at least one light reflective material 35 in the base material. By containing a light reflective material, the reflectance of the covering member is increased, and more preferably, by using low-absorbing particles, light absorption and loss can be reduced, and a covering member having light scattering properties can be obtained. Specifically, translucent particles are used. As this light reflective material, Ti, Zr, Nb, Al, S
One oxide selected from the group consisting of i or at least one of AlN and MgF, specifically TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Al ₂ O ₃ , MgF, AlN, SiO _{2. At} least one selected from the group consisting of ₂ . The particles of the light reflecting material are Ti, Zr, N
b, being one kind of oxide selected from the group consisting of Al, it is possible to make the material highly reflective and low-absorbent, and it is possible to increase the difference in refractive index from the base material, particularly the translucent resin, which is preferable. . Further, the covering member can also be constituted by a molded body made of the light reflecting material, specifically, a porous material such as an aggregate obtained by agglomerating the particles, a sintered body, or the like. In addition, a molded body by a sol-gel method may be used, and the refractive index difference between the light reflecting material and the air in the porous body is increased,
Since light reflectivity can be improved and it can be comprised with an inorganic material, it is preferable. On the other hand, the covering member provided with the base material such as the resin can be molded into a desired shape and the controllability of the covering region, and the sealing performance and the airtight performance can be improved. preferable. Further, in consideration of the characteristics of both covering members, a composite molded body of both can be obtained. For example, a part of the porous molded body is impregnated with resin on the outer surface side, and on the inner surface side of the light emitting element side, The structure can be made porous. As described above, the covering member or the surrounding body surrounding the light source unit may be configured such that the inner region communicates with the outside, or is gas permeable, and may be at least as long as light does not leak out. .

In the covering member 30 containing the light-reflecting material 35 in the base material described above, the depth at which light leaks differs depending on the concentration and density, so that the concentration and density are appropriately set according to the shape and size of the light emitting device. It is good to adjust. For example, when the wall thickness is reduced with a relatively small light emitting device, it is preferable to provide a high-concentration light reflective material. On the other hand, the concentration and particle size can be appropriately adjusted so that it is suitable for the preparation of the raw material of the covering member containing the light-reflective material, the application of the raw material, the production of the raw material, etc. The same applies to the porous body. As an example, it is preferable that the content concentration of the light reflective material 35 is 20 weight percent or more, and the thickness of the covering member 30 is 20 μm or more. Within this range, productivity is good,
From the first surface, which is the light emitting surface, emitted light with high brightness and high directivity can be obtained. Furthermore, you may add another filler in a resin base material. For example, a heat conductive material can be added, heat generated by the light source unit can be diffused efficiently, reliability can be improved, and output can be increased. Specifically, a thermal conductivity of 0.8 W / K · m or more is preferable as the thermally conductive material, for example, Ag, Cu
Examples thereof include metal materials such as diamond, alumina, AlN, glass and the like, and ceramic materials with good heat absorption, and these may be mixed and contained. Further, pigments can be mixed and colored to absorb light of a specific wavelength.

The area covered by the covering member is as described above, and will be described in detail below. By covering the side surface of the light source unit and the side surface of the wavelength conversion member, leakage of light from the side surface can be avoided, and further, emission from the side surface can be suppressed, and color unevenness in the entire emission color can be prevented. And uneven brightness can be reduced. Further, a part of the light source part is exposed, specifically, a light emitting element, a wavelength conversion member,
Further, by covering the side surfaces of the other members and exposing the top surface and limiting the light emitting region, the directivity of the emitted light and the luminance on the exit surface can be enhanced. Furthermore, the heat generated in the light source part, in particular the wavelength conversion member, is conducted to the covering member 30, and the heat dissipation can be improved as compared with the case where it is not covered. In addition to the side surface of the wavelength conversion member 40, a part of the light emitting element side surface (second surface) may be covered. Specifically, as shown in FIGS. The covering member 30 is filled with the covering member 30, and the periphery of the light emitting element 10 is encapsulated by the covering member 30. That is, on the second surface, the exposed region excluding the facing region that is bonded to the light emitting element 10 is covered. in this way,
An optical connection region and a coating region of the covering member 30 are provided on the second surface, and the side surface of the light emitting element extends from the coating region to cover the light emitting element with high efficiency. The light in the wavelength conversion member can be reflected on the second surface side and light absorption by the substrate 50 can be suppressed. Further, when a plurality of light emitting elements 10 are joined, the above problem becomes large in adjacent elements, but the covering member 30 is also filled between the elements, and a separation region between adjacent element joining regions on the second surface It is preferable that the above effects are obtained by coating.

In the light emitting device of the present invention, the exposed surface side of the covering member 30 is the first surface (outgoing surface) of the light source unit.
The reflection region of the light transmission member and the opposite region thereof are formed, and various forms can be adopted for the other exposed surface region and the inner side. For example, the covering member 30 may cover the side surface of the wavelength conversion member 40 to form an exposed surface, and the inner side of the light source unit side surface or the periphery thereof may be in contact with or separated from each other. A covering member in contact with or apart from the light emitting element is provided. As shown in the drawing, it is preferable in manufacturing that the light emitting element 10 is continuously encapsulated from the side surface and the second surface of the wavelength conversion member and the light source portion is embedded. On the other hand, on the inside side, in addition to the case of contacting in this way, the covering member 30 can also be spaced apart from the side surface of the light emitting element 10, and the gap is provided between them so that the interface with the gap is provided. Reflection can be realized, and the coating member such as resin can be prevented from being deteriorated by light and heat, which is preferable. Further, a plurality of light emitting elements 10
It is possible to provide a structure in which the gap is also provided in the separated region. At this time, it is preferable to form an exposed portion having a high refractive index difference between air and gas in the internal space of the gap so that the refractive index difference with the light emitting element 10 is preferably increased.

In the present invention, the light transmissive member includes a reflective region on the light incident side surface, outside the incident region of the light source unit, and the reflective region is provided on the surface of the light transmissive member and further on the interface with the covering member.
The reflection function greatly depends on the material and surface form of each member. In Embodiment 1, by being formed at the interface between the covering member containing the light reflecting material and the light transmitting member formed thereon,
Suitable reflection and scattering functions are provided. Specifically, by being mutually transparent materials, an interface between the transparent materials is formed, a high reflectance is obtained, and further, a scattering function by the light reflective material in the covering member is given. The Thereby, it is possible to improve the light extraction efficiency, brightness, and color unevenness, especially when the apparatus is downsized, that is, the ratio of the light source portion L is large, or the diameter of the light transmitting member is small or the shape is deformed from a spherical surface, The effect increases when flattened. At this time, it is particularly preferable that a difference in refractive index is provided in each member constituting the interface, and a large refractive index is
The light transmitting member side preferably improves the reflectivity of the translucent material interface and improves the output of the device, and the coating member side preferably captures and scatters a large amount of light. This is preferable because of its superiority in brightness, luminance and chromaticity distribution. Therefore, not only the optical element function of the light transmitting member described above, the interface between both members described later, and the shape of the reflecting surface, but also the material and composition of both members, as well as the concentration and distribution of the reflecting material in the covering member are adjusted. By doing so, the light emitting device of the present invention can appropriately control the light emission characteristics. In particular, when the wavelength conversion member is included in the light source unit, the chromaticity and luminance distribution of the light emitted from the light source unit are peculiar depending on the properties of the member such as the shape, but this can be controlled by the function of the reflection region. preferable. Furthermore, since both the members are made of resin, the resin interface can be formed in a desired shape, and as will be described later, it is preferable to design devices having various directivities and the like.

As described above, the light emitting device of the present invention has two regions surrounding the light source part, one light transmitting member side is a light guiding region having a light emitting surface, and the other covering member side is lighter than that. The light source part has a structure in which a light emitting portion is exposed from the coating region and is coupled to the light guide region, and a reflection region is provided at the boundary between the light guide and the coating region. ing. By surrounding the light source part with these two regions and providing the incident region and the reflection region at the junction or boundary region, the above-described functions and effects are appropriately expressed, and the desired emission characteristics, A light-emitting device that can be downsized is obtained. In particular, it is preferable that the emission surface of the light source unit is a surface light source and a planar incident region, so that the reflection region at the boundary portion continuous therewith can function in cooperation. On the other hand, it is preferable that the covering region is suitably formed, that is, provided at the boundary between the two regions, as will be seen in the examination of the device 140 and models DD and DA described later. For example, the outer edge of the light transmitting member wider than the covering member is opposed to the mounting substrate exposed from the covering member, and the boundary is provided, so that the characteristics of the apparatus are greatly influenced by the substrate surface having low reflectivity. In another example, when leakage light from the light source unit or its path is provided on the side surface or mounting side surface of the light source unit, the amount of light is large, which greatly affects output and efficiency reduction. For example, the side surface of the light emitting element and the surface (substrate side, mounting side) facing the incident region are exposed from the covering member, and the surface having a lower reflectance and higher light absorption than the covering member such as the substrate surface is exposed there. The effect becomes remarkable. Therefore, it is preferable that either the surface of the light source unit is covered or the exposed surface of the low reflectance or high absorptance is covered, and preferably both are formed. Is a structure having both of them. However, it is preferable that the covering region is provided so as to face substantially the entire region of the light guide region, and that the light incident side surface of the light transmitting member is included in the surface of the covering member. It is preferable that a region other than the emission surface is covered. Specifically, as shown in the figure, a cover member is provided as an underfill on the opposite surface side of the light emitting element, and both are provided. For example, the precoat and underfill covering the light emitting element and the light source part are made of a transparent resin with low reflection. The surface of the substrate and the surface of the substrate and the surface of the substrate are exposed, and a light leakage path from the light source unit is prevented from being formed. Accordingly, the surface facing the emission side of the light source part is included by the covering member and the covering area, that is, the surface of the facing covering member and covering area (surface on the substrate 50 side in the figure) is covered by the covering member from the light source part. Preferably they are separated.

The reflective surfaces provided at the boundary between the light guide region and the coating region are provided on the surfaces of each region facing each other, and are provided at the interface when both are joined as in the first embodiment.
In the former case, as in the second embodiment, when facing each other apart from each other, a reflection function is provided and superimposed on each facing surface of the light transmitting member and the covering member, so that high light extraction efficiency is achieved. In the latter, since the reflection function is given at the boundary region and the interface of the member, the directivity can be easily controlled. Therefore, the reflective surface can be a desired reflective function in the molding of each region and each member,
If the inclination of the surface is substantially flat with respect to the incident region, light is extracted in the emission direction of the light source unit. On the other hand, when the reflecting surface is inclined outward as in the second embodiment, for example, the normal line When the direction is inclined outward with respect to the optical axis of the light source unit, a wide directivity is obtained. Conversely, when the direction is inclined inward, light emission with high luminance is preferable. In addition, a structure provided with various optical surfaces such as a convex curved surface and a concave curved surface can obtain desired light emission characteristics. Further, in the case of a scattering covering member containing a light reflecting material, each region, Different reflection functions can be provided on the respective opposing surfaces of the member. When both are joined, the above-described interface reflection and internal scattering functions can be imparted. When both are separated, light extraction is promoted by irregular reflection on the surface of the covering member. Can with structure. As described above, the reflectance of the covering region and the covering member, for example, the concentration of the light reflecting material may be constant as in the embodiment and the example, and different regions may be provided or distributed. Or you may. As a result, a different reflection function can be given to each region and part, for example, the concentration of the light reflecting material is changed in the inner region on the light source unit side and the outer region outside it, or each region is coated with a coating member having a different concentration. It is possible to form a light-emitting device having different scattering properties in each of the inner and outer regions. For example, it is possible to increase the scattering property by using the outer region as a high-concentration light reflecting material to reduce the color unevenness of the outer edge portion of the emitted light.

(Light transmission member)
The light transmitting member 20 can be bonded to the first surface of the light emitting element 10 or the first surface of the wavelength conversion member 40 to improve the light extraction efficiency. The light transmitting member 20 has at least a light emitting side surface 21 and a light incident side surface, and the light emitting side surface 21 can be formed in various shapes according to the purpose. For example, as described above, the surface 21 on the light emitting side is formed as a convex lens having a convex curved surface or a spherical surface (semispherical surface), so that uniform transmission characteristics (critical angle) can be obtained with respect to light incidence at all azimuth angles.
And can efficiently extract light to the outside. Moreover, not only a spherical surface but a desired curvature,
The light emission angle can be made smaller than that of the spherical surface by adopting a convex lens shape, for example, a bullet shape. In addition, the light may be diffused by forming a concave curved surface or a concave lens shape.
As described with reference to FIG. 9, an optical element having desired directivity may be used.

The light transmissive member 20 is formed using a resin material such as an epoxy resin, a silicone resin, a modified silicone resin, a urea resin, a urethane resin, an acrylic resin, a polycarbonate resin, and a polyimide resin, similarly to the base material of the covering member 30. can do. In addition, since the light transmission member 20 also plays a role as a sealing material for protecting the light emitting element 10 and the wavelength conversion member 40, a material excellent in weather resistance, heat resistance, and hardness is preferable, and an epoxy resin or a hard silicone resin is preferable. Is preferable, and glass may be used. Further, the above-described phosphor and / or the above-described light scattering particles such as TiO ₂ and / or the above-described filler such as quartz glass, and the above-described pigments are added to the light transmitting member 20 as appropriate. The desired light emission characteristics can be obtained, and the same applies to a light-transmitting resin material such as the light-transmitting member and the adhesive 15. Further, the light transmitting member 20
Can be formed into a desired size and the desired shape as described above by compression molding, transfer molding, or the like.

(Mounting board)
On the other hand, in the light emitting device 100 of FIG. 1, the substrate 50 on which the light emitting element 10 is mounted is as follows.
It is possible to use at least the surface formed with the wiring 51 connected to the electrode of the element, and an external connection wiring 52 (FIGS. 7 and 9) may be provided. The substrate material is, for example, aluminum nitride (AlN), single crystal, polycrystal, sintered substrate, other materials such as ceramics such as alumina, glass, semi-metal or metal substrates such as Si, and laminates thereof. Bodies and composites can be used, and metallic and ceramic materials are preferred because of their high heat dissipation. Note that the substrate 50 may not have wiring. For example, in the form in which the growth substrate side is mounted with the element of FIG. 5 and the electrode of the element is wire-connected to the electrode of the apparatus, or the wavelength conversion member is provided with wiring. But you can. Moreover, the form which covers the outer side surface of the mounting board | substrate 50 other than the form in which the coating | coated member 30 is provided on the mounting board | substrate 50 like the light-emitting device to show in figure may be sufficient. Further, it is preferable that at least the surface of the mounting substrate 50 is made of a highly reflective material. As shown in FIGS. 1 and 2, the light emitting element 10 is bonded onto the wiring 51 by a conductive adhesive 60 and is electrically connected to the outside. Conductive adhesive 6
For 0, solder, Ag paste, Au bump or the like can be used.

(Frame body, laminated substrate, base material)
The light emitting device 100 shown in FIG. 1 has a frame 55 and is a holding member for the covering member 30. The frame body 55 can be formed of ceramic, resin, or the like. Alumina having high light reflectivity is preferable, but not limited to this as long as a reflective film is formed on the surface. If it is resin, besides using screen printing or the like, the molded body may be bonded to the mounting substrate. Further, it is preferable to increase the reflectance by using a light reflective material in the same manner as the covering member 30. Moreover, you may color a frame according to the objective like the said addition member. In addition, this frame can also be removed after filling or forming the covering member. Further, the frame body may be formed integrally with the mounting substrate of the light emitting element, such as a laminated substrate 56, a base of a device base having a cavity structure, or the like.

(Adhesive)
An adhesive 15 may be interposed at the interface between the light emitting element 10 and the wavelength conversion member 40, thereby fixing both members. The adhesive 15 is preferably made of a material that can effectively guide the emitted light from the light emitting element 10 toward the wavelength conversion member 40 and optically connect both members. Examples of the material include resin materials used for the above-described members. As an example, a translucent adhesive material such as a silicone resin is used. A similar translucent adhesive may be provided on the optical path between other members, for example, the adhesive 55 in the second embodiment (FIG. 7).

(Method for manufacturing light emitting device)
An example of a method for manufacturing the light emitting device 100 shown in FIG. 1 will be described below with reference to FIG. First, as shown in FIG. 6A, bumps 60 are formed on the substrate 58 or on the light emitting element 10, and the light emitting element 10 is flip-chip mounted through the bumps 60. In this example, one LED chip is mounted side by side in a region corresponding to one light emitting device on the submount substrate 58 (however, the number of LED chips can be changed as appropriate). Next, the first surface side of the light emitting element 10 (
On the back surface of the sapphire substrate 1 or the exposed surface of the nitride semiconductor 11 if the substrate is removed)
The wavelength conversion member 40 is laminated by applying a silicone resin as an adhesive. Thereafter, the silicone resin is thermally cured to bond the light emitting element 10 and the wavelength conversion member 40 together. Further, a frame body 57 having a predetermined size and shape is erected around the light emitting element 10. Here, the frame 5
7 is lower than the first surface of the wavelength conversion member 40, but may be substantially the same or higher.

Next, a liquid resin 31 containing light-reflective particles is potted by a dispenser (liquid quantitative discharge device) 71 or the like so as to cover the side surface of the wavelength conversion member 40 in the frame 57. The dropped resin 36 crawls up on the wall surface side of the light emitting element 10 by surface tension and covers the side surface of the wavelength conversion member 40. Then, the resin 36 is cured to form a covering member 37.
Here, the covering member 37 is formed with a concave portion that is recessed at a position lower than the first surface of the wavelength conversion member 40 on the surface, in other words, the convex surface in which the first surface of the wavelength conversion member 40 is disposed at the highest position. The surface of the covering member 37 is an inclined surface in the periphery thereof. Next, as shown in FIG. 6B, an appropriate amount of a liquid thermosetting resin 26 serving as a light transmission member is dropped onto the covering member 37 and the wavelength conversion member 40 by a similar dispenser or the like. Subsequently, as shown in FIG. 6C, a predetermined pressure is applied from above to the upper mold 72 on which a hemispherical lens mold is formed to compress the resin layer 26, and in this state, a predetermined time is reached. The resin layer 26 is primarily cured by holding. Here, it is preferable to set the heating temperature and the heating time in the mold so as to reach a hardness sufficient for the resin to maintain a predetermined shape. For example, the primary curing temperature is 100-17.
The temperature is 0 ° C, preferably about 120 to 150 ° C. The curing time is 200 to 900 seconds, preferably 250 to 600 seconds. Further, a lens having a desired lens diameter and a curvature radius can be formed according to the shape of the inner surface of the upper mold 72.

Further, as shown in FIG. 6D, a substrate provided with a series of light emitting devices on which a resin molded body 27 having a desired lens shape is formed is taken out of the mold and heated under predetermined conditions to form a resin. The body 27 is secondarily cured. The secondary curing conditions are such that, for example, the temperature of the secondary curing is equal to or higher than that of the primary curing so that the resin molded body 27 is sufficiently cured, and the time of the secondary curing is set longer than that of the primary curing. It is preferable to do. In the case of an epoxy resin or a hard silicone resin, the secondary curing time is set to about 3 to 5 hours. If secondary curing is sufficiently performed in this way, it is possible to prevent unreacted curing components from remaining in the resin molded body 80 and adversely affect the reliability of the light emitting device. Also,
By performing secondary curing after removal from the mold, the throughput of the process can be increased. Finally, dicing is performed at a predetermined position (for example, a dotted line A in FIG. 6D), and the light emitting device 100 in FIG.

(Embodiment 2)
FIG. 7A is a schematic cross-sectional view of the light emitting device 200 according to Embodiment 2 of the present invention.
(B) is a schematic sectional drawing for demonstrating the light source periphery part. In the light emitting device 200, the structure other than the light transmitting member 20 is substantially the same as that of the first embodiment. Therefore, the same components are denoted by the same reference numerals and the description thereof is omitted as appropriate. The light-emitting device 200 has a configuration in which a light-transmitting member 20 formed in a hemispherical shape having a diameter R (= W) is bonded to the first surface of the wavelength conversion member 40 via a light-transmitting adhesive 28. ing. In the light emitting device 200,
On the light incident side surface of the light transmitting member 20, an incident region 82 joined to the adhesive 28 with a diameter L2 and a reflection region 92 outside thereof are provided. The reflective region 92 and the surface 93 of the covering member are spaced apart from each other, and a gap 85 is provided between them. And the light extraction efficiency can be improved. As can be seen from the above analysis result shown in FIG. 4, the light emitting device 2 according to the second embodiment.
00 has higher light extraction efficiency than the light-emitting device 100 of Embodiment 1, and has an excellent configuration when the light source is small and the device is small, particularly when the light source is large. In addition,
The light transmissive adhesive material 28 is preferably a material having a refractive index substantially equal to that of the light transmissive member 20 to be joined. This is to reduce the reflection of light at the interface between the light transmitting member 20 and the light transmitting adhesive material 28 and to improve the optical coupling efficiency. It can be realized easily.

Further, the light-transmitting adhesive 28 that is interposed between the first surface of the wavelength conversion member 40 that is the exit surface of the light source unit, on the surface opposite to the light source unit side incident region 82, that is, on the light incident side surface. An incident region 81 having a diameter L1 is provided at the interface, and a reflective region 91 is provided at the interface between the surface of the covering member. This diameter L
2 is preferably larger than the diameter L1, whereby light can be efficiently guided from the light source unit to the light transmitting member 20. Further, by providing the reflection region 91, the return light in the translucent adhesive can be reflected and scattered on the surface of the covering member, and the light coupling efficiency to the light transmitting member 20 can be improved. It should be noted that the light-transmitting adhesive material 28 is covered with the covering region (the light incident region 8).
1 and the reflective area 91) and the ratio of the reflective areas 91 and 92 outside the light source section can be adjusted by the range of the covering / joining area between the reflective area 93 of the covering member exposed from the adhesive, for example, a light transmitting member The substantially entire area of the surface on the light incident side of 20 may be covered with the light-transmitting adhesive 28.
In this case, the space between the light transmissive member and the covering member is filled with the light transmissive adhesive material to form a transparent region, and light transmission from the light transmissive member 20 into the light transmissive adhesive material 28 is promoted. In the same manner as in No. 1, the return light is reflected by the reflection region 91 on the surface of the covering member and extracted outside. That is, the light-transmitting adhesive is interposed, and the incident surface side 25 is separated from the emission surface 81 of the light source unit and the covering member surface 93, so that the light propagates in the separated regions sandwiched between the surfaces. Reflected on the surface 93,
Since the light is scattered and is also reflected by the reflective region 92 facing it, an efficient reflective structure can be obtained.

(Embodiment 3)
FIG. 8 is a schematic cross-sectional view for explaining the periphery of the light source unit of the light emitting device according to Embodiment 3 of the present invention. Note that the structure around the light source portion of the light-emitting device described here can also be applied to the structure of the light-emitting device in other embodiments. The incident region 83 of the light transmitting member has a concavo-convex structure so that incident light from the light emitting element 10 and / or the wavelength conversion member 40 of the light source unit can be scattered, and return light can be reflected and scattered. The reflection function by the region 90 can be supplemented, the directivity of the emitted light from the light emitting surface can be widened, and unevenness in brightness and color can be easily reduced. In particular, when a plurality of light emitting elements 10 are mounted on one wavelength conversion member 40, the influence of the arrangement of each light emitting element 10 and the resulting light distribution, luminance unevenness, and color unevenness are large and reduced. Therefore, it is preferable. In addition, the uneven surface is expected to improve the adhesion of both members in addition to the optical coupling efficiency. Also,
Such a concavo-convex structure can be provided not only on the surface of the wavelength conversion member, but also on the light emitting element side surface, and further on the surface of each member on the optical path, and in particular, the light source part and the light transmission member , Or in the light source part, for example, on the surface of the substrate 1 on the semiconductor layer 11 side. Although not described in detail in the embodiment, such a structure is used. Uneven surface 4 of wavelength conversion member
The concavo-convex structure such as 3 can be provided by polishing, dry etching, wet etching or the like, and an irregular concavo-convex structure can be formed in addition to the irregular concavo-convex structure.

In the light emitting device shown in FIG. 8, the light emitting element 10 has a structure in which a semiconductor element structure 11 having a plurality of light emitting regions (light emitting layers) separated from each other is provided on one growth substrate 1. In this way, by joining a single light emitting element and further forming the light emitting element 10 in which the growth substrate 1 is integrated and the light emitting region is separated, a plurality of light emitting elements 1 are combined in one wavelength conversion member 40.
Compared with the case where 0 is mounted, it is possible to reduce the influence of the arrangement and light distribution of the light emitting elements 10. Furthermore, the wavelength conversion member 40 has a width smaller than the width of the first surface of the light emitting element 10 (the back surface of the growth substrate 1), that is, at least a pair of opposing side surfaces of the wavelength conversion member 40 are
It is located inside the side surface of the light emitting element 10. In this form, the luminance can be relatively increased by narrowing the light emitting area, and the ratio of the primary light and secondary light color mixture can be made uniform in the surface, and the wavelength conversion member 40 as in the first embodiment. If the side surface of the light-emitting element 10 is located on the same plane as the side surface of the light-emitting element 10, the amount of light from the light-emitting element 10 is insufficient at the outer edge of the wavelength conversion member and color unevenness is likely to occur. it can. However, “substantially the same surface” in the present specification may be substantially the same surface in terms of the functions described above. For example, the wavelength conversion member 40 and the light emitting element 10 have a size of about ± 10% as compared with the dimensions. can do. Furthermore, in the light-emitting device shown in FIG. 8, the light-emitting element 10 and the wavelength conversion member 40 are directly joined without using a translucent adhesive. Such bonding can be realized by surface activation, crystal bonding by thermocompression bonding, etc., and by not using an adhesive which is a resin material having a relatively low refractive index, it does not increase the interface with different refractive index, and the bonding efficiency is increased. The heat dissipation from the wavelength conversion member 40 can also be improved.

(Embodiment 4)
FIGS. 9A, 9B and 9C each show a light emitting device 30 according to Embodiment 4 of the present invention.
2 is a schematic cross-sectional view of 0, 400, and 500. FIG. The fourth embodiment shows a modification of the shape of the light transmitting member 20 and its light emitting side surface in the light emitting device according to the present invention, and can be applied to each of the embodiments, and other main structures. Since this is substantially the same as that of the first embodiment, the same components are denoted by the same reference numerals and description thereof will be omitted as appropriate.

The shape of the surface 21 on the light emitting side of the light transmitting member 20 in the light emitting device 300 of the example shown in FIG. 9A has a convex curved surface that is a flat shape from a hemispherical surface. More specifically, as indicated by the black circle in the figure, the center of curvature is located at a position Y away from the center of the surface of the wavelength conversion member 40, and the surface 21 has a diameter R (curvature radius) centered on it. r = R / 2), and the diameter (cross-sectional width) W is W = 2 × (r ² −Y ² ) ^1/2 . Device 140 described above, model D
As shown in (DA), the light-emitting device 20 can be made smaller and thinner by making the light-transmitting member 20 flat, but when the surface 21 changes from the hemispherical surface, Light reflection increases. However, in the light emitting device of the present invention, since the reflection region 90 occupies most of the light incident side surface of the light transmissive member 20, the light in the light transmissive member is reflected and scattered by the light reflecting material 35 there. By doing so, it can be efficiently taken out to the outside. In the figure, the covering member 30 is sufficiently wider in cross section than the light transmitting member 20, but it goes without saying that both end portions can be made substantially the same. In addition, the light emitting device 300 includes the substrate 50.
A Zener diode electrically connected to the light emitting element 10 is provided on the top. Thus, the protective element 14 for electrically protecting the light emitting element is embedded in the covering member 30 as shown in the figure, and if it is separated from the light source part and the reflection region, it is optical with respect to other main components. The light emitting device and the covering member can be made substantially equal in diameter to the light transmitting member, that is, if the light emitting device and the covering member are arranged inside the light transmitting member 20 and in the reflection region 90, the light emitting device can be reduced in size. This is preferable because it does not interfere with the process.

In the light emitting device 400 of the example shown in FIG. 9B, the shape of the light transmitting member 20 is the wavelength converting member 40.
The upper surface 22 consisting of two convex curved surfaces intersecting directly above the center of the light source and the side surface 23 thereof, the emitted light from the surface of the light source section passes through the incident region 80, and the upper surface 22 is mainly used as a reflection surface laterally. And the side surface 23 is taken out of the apparatus mainly using the light emitting surface. On the upper surface 22,
In order to enhance the reflection function, a reflective film such as a metal film, a dielectric multilayer film, or a covering member containing the light reflective material 35 may be formed. Further, in such a light emitting device, the extraction efficiency is enhanced by reflection and scattering by the upper surface 22 and the reflection region 94, and color unevenness of the emitted light of the wavelength conversion member 40 is further reduced. In addition, the wavelength conversion member 4 is thereby obtained.
The 0 side surface may be exposed from the covering member 30.

In the light emitting device 500 of the example shown in FIG. 9C, the light transmitting member 20 has a shape formed by a flat upper surface 23 and a side surface 24 formed of a curved surface inclined toward the inner light source unit. Have. Thereby, the emitted light from the surface of the light source section passes through the incident region 80, is condensed upward by the side surface 24, and is taken out from the upper surface 23 to the outside of the apparatus. Note that a similar reflective film may be formed on the side surface 24 as described in the light emitting device 400, and, as indicated by a dotted line in the figure, a new frame is newly formed on the frame 56. It is also possible to fill the covering member containing the light reflecting material 35 and form a laminated structure of the second light reflecting layer covering the light transmitting member 20.

Each of the above examples shows an application example to various light transmission members in the light emitting device of the present invention. In the devices of FIGS. It is provided and an incident area of the light source part is provided inside thereof. In particular, in the light transmissive member having various shapes instead of the convex curved surface as in FIG. 9A and other embodiments, more light is confined inside the light transmissive member than the convex curved surface, and the reflection region described above, Other structures work well. Also, in the relationship between the diameter L of the light source unit and the diameter W of the light transmitting member, the relationship between the L / W ratio and the light extraction efficiency tends to become more prominent, and the drop in efficiency tends to increase. it is conceivable that.
As described above, the apparatus shown in FIGS. 9B and 9C has a structure in which, in addition to the reflective region facing the covering member on the incident surface side, the reflective surfaces are also provided on the surfaces 22 and 24 different from the reflective region. Further, a light emitting surface 23 is provided, and with this structure, suitable reflection and scattering by the covering member can be performed in a part of the reflection region, particularly in the vicinity of the light source unit, and a device having desired light emission characteristics can be realized.

(Embodiment 5)
FIG. 10 is a schematic cross-sectional view of light-emitting device 600 according to Embodiment 5 of the present invention. Other main structures except for the mounting form of light-emitting element 10 are substantially the same as those in Embodiment 1, and therefore Similar components are denoted by the same reference numerals, and description thereof is omitted as appropriate. In the light emitting device of the present invention, the light source part is covered with the light reflective covering member 30 and optically coupled to the light transmitting member. The covering form, specifically the light emitting element mounting form and the covering member form, Various forms can be taken. The light-emitting device 600 of FIG. 9 is an example thereof, and does not have the substrate 50 and the covering member 3.
0 is formed into a rectangular parallelepiped shape and a plate shape, and this formed body constitutes the exposed surface of the light emitting device together with the light transmitting member 20. A conductor 61 connected to each electrode of the light emitting element 10 is provided, and the covering member 30
An external connection portion is formed so as to reach the back surface side. The extending direction of the conductor 61, the exposed position,
The surface can be appropriately changed. For example, the surface may be extended to the outside on the same surface side as the light transmission member 20 and exposed. The conductor 61 may be combined with a layered form in addition to the columnar form as shown in FIG. With such a light emitting device 600, the light source part such as the light emitting element 10 can be almost completely encapsulated by the covering member 30 except for the incident region 80 of the light source part, and the light emitted from the light source part is mounted on the mounting substrate 50. , It can reduce the absorption and loss by the conductor wiring, etc.
The light extraction efficiency from the light source unit can be increased.

Such an apparatus is, for example, mounting a light emitting element on a support substrate, applying a covering member to form a molded body, and performing surface treatment with a release agent or the like in advance, and removing from the support substrate. This can be realized by a method of taking out the molded body of the covering member in which the light source part is embedded. Other structures are
The light transmitting member may be molded or adhered before or after the molded body is peeled off, or may be cut into individual devices before and after the peeling, and further a light transmitting member using a support substrate such as a mold. The molded body may be formed on the top. In addition, the wiring structure of the light source part is placed with the surface of the incident region 80 facing the support substrate, and the electrode of the light emitting element and the conductor thereon are formed, plated,
The conductor may be formed by bumps or the like, and the covering member may be formed. The wiring-side surface is placed facing the support substrate, and the conductor or the light-emitting element side, the support substrate side, or both in advance. A wiring layer on the supporting substrate and a conductor combining them may be provided and peeled off.

Examples according to the present invention will be described in detail below. Needless to say, the present invention is not limited to the following examples.

(Examples 1-3)
In the light emitting devices of Examples 1 to 3, the light emitting element 10 as shown in FIG. 7, or the element and the wavelength conversion member 40 bonded to the element are covered with the side surfaces of the covering member, and the emission surface on the upper surface of the exposed light source unit This is a structure in which the lens 20 is bonded to the top via an adhesive 28. Specifically, on the wiring 51 of the AlN ceramic substrate 50, a substantially square blue LE of about 1 mm × 1 mm as the light emitting element 10.
One D-chip is flip-chip mounted with bumps 60. In Example 1, the LED
The side surface of the LED chip is encapsulated with the covering member 30 filled in the periphery of the light emitting surface of the sapphire substrate, which is the growth substrate 1. The covering member 3
0 is a silicone resin containing the light-reflecting material 35, which is fine particles of TiO _{2 having} a particle size of about 270 nm, at a concentration of about 23 weight percent. Further, in Examples 2 and 3, one YAG sintered body, which is a plate-like wavelength conversion member 40, is bonded onto the growth substrate 1 of the LED 10 by a translucent adhesive 15 made of silicone resin. Then, as shown in the drawing, in a state where the emission surface of the surface of the wavelength conversion member 40 is exposed, a part and a side surface of the bottom surface of the wavelength conversion member 40 with the covering member 30, a side surface of the LED chip, etc. The surface is encapsulated. In addition, the surface of the covering member 30 is inclined near the light source unit so as to scoop up a side surface continuous from the emission surface of the light source unit as illustrated. The outer shape of the wavelength conversion member 40 is about 1.1 in the second embodiment.
mm × 1.1 mm, in Example 3, it is a rectangular shape of about 1.5 mm × 1.5 mm, and the thickness is about 1
50 μm. And about each Example, it is the light emitting element 10 on the surface of a coating | coated member.
Alternatively, the hemispherical lens-shaped light transmissive member 20 having a diameter R of about 4 mm made of silicone resin is the same so as to include the emission surface of the light source portion of the wavelength conversion member 40 and the optical axis positioned at substantially the center thereof. The light-transmitting adhesive 28 made of silicone resin is joined to the emission surface.

The ratio (L / R) of the diameter L of the light source part to the diameter R of the light transmitting member 20 is about 0.250 in Example 1, about 0.275 in Example 2, and about 0.375 in Example 3. is there. Example 1
The blue single-color light-emitting device has an emission peak wavelength of 449 n at a drive current of 350 mA.
m, emits light at a light emission output of 522 mW. In addition, the white light emitting device of Example 2 has a relatively high luminance with a luminous flux of 115 lm (chromaticity y value 0.38) at a driving current of 350 mA and a luminous flux of 170 lm (same chromaticity y value) at a driving current of 550 mA. . The white light emitting device of Example 3 has a luminous current of 135 lm (chromaticity y value 0.38) at a driving current of 350 mA, a driving current of 5
At 50 mA, a luminous flux of 200 lm (same chromaticity y value) results in a relatively high luminous flux.

(Examples 4 to 6)
Next, the configuration of the wavelength conversion member 40 is changed, and the influence on the light emission efficiency due to the presence or absence of the light transmission member 20 will be verified below. The light-emitting device of Example 4 is the same as that of Example 3. Each of the light-emitting devices of Examples 5 and 6 is changed only in the configuration of the wavelength conversion member 40 of Example 4, and in Example 5, Using a sheet in which the same YAG phosphor was dispersed in a silicone resin, in Example 6, a phosphor of (Sr, Ba) ₂ SiO ₄ : Eu silicate was dispersed in a silicone resin in the same manner as in Example 5. It is a sheet. These resin sheets are produced by spin-coating a resin in which a phosphor is diffused onto a plate coated with a release agent, curing the resin, and cutting it into a predetermined size. In these light emitting devices of Examples 4 to 6, the difference in luminous efficiency depending on the presence or absence of the light transmitting member 20 is shown in FIG. In addition, after mounting the light transmission member 20 of Examples 4, 5, and 6, D, E, and F, respectively.
And d, e, and f before the light transmitting member 20 is mounted, respectively. As shown in FIG. 11, in any of the embodiments, by mounting the light transmitting member 20, it is possible to increase the efficiency in light emission of the same chromaticity, and to confirm the improvement of the light emission efficiency.

When a sintered body is used as the wavelength conversion member 40, it may be difficult to produce a sintered body, conversion efficiency may be reduced, or restrictions may be imposed on the firing of two or more types of phosphors. is there. On the other hand, a sheet produced by diffusing a phosphor into a resin can be produced regardless of the type of phosphor because the production temperature is low and the characteristics of the phosphor are not impaired. For example, FIG.
As shown in FIG. 1, the resin sheet using the silicate phosphor exhibits a higher conversion efficiency than that using the YAG phosphor. Further, the surface of the plate coated with the release agent may be flat, or a concavo-convex structure may be formed on the resin sheet as the concavo-convex surface.

The light emitting device of the present invention can be suitably used for backlight light sources such as illumination light sources, LED displays, liquid crystal display devices, traffic lights, illumination switches, various sensors, various indicators, and the like.

DESCRIPTION OF SYMBOLS 10 ... Light emitting element (1 ... Growth substrate, 2 ... 1st conductivity type (n-type) semiconductor layer, 3 ... Active layer, 4 ... 2nd conductivity type (p-type) semiconductor layer, 5 ... Translucent conductive layer, 6 ... Second electrode (p-side pad electrode), 7
... 1st electrode (n side pad electrode), 8 ... Protective film), 11 ... Semiconductor element structure,
14 ... protection element, 15 ... adhesive, 16 ... light emitting part,
20 (20a to d) ... light transmitting member (21 ... light emitting side surface, 22, 24, 25 ... reflecting surface,
23 ... Light emitting surface) 26 ... Resin layer, 28 ... Adhesive,
30 to 34: covering member, 35 ... light reflective material,
40: Light transmission (wavelength conversion) member,
50, 58... Mounting substrate / base material (51-52 ... wiring pattern, 55-57 ... frame or laminated substrate or base material), 60 ... conductive adhesive, 61 ... conductor, 71 ... dispenser, 72 ... top Mold

Claims (3)

A covering member containing a light reflective material;
A light-transmitting member having a light-emitting surface and a light-incident-side surface disposed in the surface facing the surface of the covering member;
In the light incident side surface of the light transmitting member, a light source element coupled to an incident region surrounded by an outer reflective region and partially embedded in the covering member, a light emitting element, and the incident region of the light emitting element A wavelength conversion member coupled to the side and excited by the light emitting element;
A light emitting device comprising: The light transmitting member has a convex curved surface on the light emitting side, and at least a reflective region on the light incident side is a substantially flat surface,
The light-emitting device according to claim 1, wherein a cross-sectional width of the incident region is not more than half of the light incident side surface. A covering member containing a light reflective material;
A light transmissive member having a light emitting side surface of a convex curved surface and a light incident side surface disposed in the surface opposite to the surface of the covering member;
A light source part is provided on the light incident side surface of the light transmitting member, which is coupled to an inner incident area surrounded by a reflective area of a substantially flat surface and is partially embedded in the covering member. A light emitting device provided in
The light emitting device, wherein a cross-sectional width of the incident region is equal to or less than half of the light incident side surface.

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