JP7208536B2 - light emitting device - Google Patents

Description

The present invention relates to light emitting devices.

2. Description of the Related Art In recent years, white light-emitting devices in which light-emitting elements and phosphors are combined have been widely used. For example, Patent Document 1 discloses a light-emitting device in which a red light-emitting portion in which a near-ultraviolet LED chip is covered with a material containing a red phosphor and a blue LED chip are covered with a first sealing material mixed with a yellow phosphor. (Fig. 9 of Patent Document 1, Embodiment 3). According to Patent Document 1, the light emitting device of Patent Document 1 is said to be able to improve color mixing and reduce color unevenness of emitted light.

JP 2013-120812 A

However, in recent years, there has been a demand for a light-emitting device capable of further improving color mixing properties and further reducing color unevenness of emitted light.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a light-emitting device capable of further improving color mixing properties and further reducing color unevenness of emitted light.

A light-emitting device according to one embodiment of the present invention comprises:
a base, a first light emitting element provided on the base, a second light emitting element provided on the base, a transparent body made of an inorganic material having an upper surface and a lower surface, and a lower surface of the transparent body a first phosphor layer provided on the substrate, a first wavelength conversion member provided on the first light emitting element, and the second light emitting element and the first wavelength conversion member on the base so as to cover the and a second wavelength conversion member provided in and including a sealing resin and second phosphor particles.

The light-emitting device according to one embodiment of the present invention can further improve color mixing properties, and can further reduce color unevenness of emitted light.

2 is a top view of the light emitting device of Embodiment 1. FIG. FIG. 2 is a cross-sectional view along line AA of FIG. 1; FIG. 3 is a sectional view showing an enlarged part of FIG. 2; 3 is a top view of a base 30; FIG. 2 is a diagram showing circuit configurations of a first light emitting element and a second light emitting element in the light emitting device of Embodiment 1. FIG. FIG. 10 is a top view of the light emitting device of Embodiment 2; 4 is a top view of a substrate 60; FIG.

A light emitting device according to an embodiment will be described below.
The light-emitting device described below is for embodying the technical idea of the present disclosure, and unless there is a specific description, the present disclosure is not limited to the following.
Embodiment 1.
As shown in FIGS. 1 and 2, the light-emitting device of Embodiment 1 includes a substrate 30, a plurality of first light-emitting elements 1 provided on the substrate 30, and a plurality of second light-emitting elements 1 provided on the substrate 30. a substrate so as to collectively cover the element 2, the first wavelength conversion member 10 provided on the first light emitting element 1, the second light emitting element 2, the first light emitting element 1, and the first wavelength conversion member 10; and a second wavelength conversion member 20 provided on 30 .

In the light emitting device of Embodiment 1, the substrate 30 is, for example, a substrate having a flat upper surface, and wiring for supplying power to the first light emitting element 1 and the second light emitting element 2 is provided on the upper surface of the substrate 30. . The wiring provided on the upper surface of the substrate 30 includes a first wiring 31 for supplying power to the first light emitting element 1 and a second wiring 32 for supplying power to the second light emitting element 2 . A frame 33 is provided on the upper surface of the base 30 so as to surround the mounting area where the first light emitting element 1 and the second light emitting element 2 are mounted. A plurality of first light emitting elements 1 and a plurality of second light emitting elements 2 are arranged in the following arrangement in the mounting area inside the frame 33 on the upper surface of the base 30 .

In the light emitting device of Embodiment 1, the planar shape of the first light emitting element 1 and the planar shape of the second light emitting element 2 are polygonal shapes such as substantially rectangular shapes when viewed from above. The first light emitting element 1 or the second light emitting element 2 is arranged, for example, so that its center coincides with a lattice point of the rectangular lattice, in other words, it is substantially parallel to one of the two pairs of opposite sides of the rectangular lattice. are arranged side by side in a direction parallel to the other opposite side. Here, in this specification, the light-emitting elements arranged in a direction substantially parallel to one opposite side of the rectangular lattice are called rows, and the light-emitting elements arranged in a direction roughly parallel to the other opposite side are called columns. In the light-emitting device of Embodiment 1, the first light-emitting elements 1 and the second light-emitting elements 2 are arranged in rows or columns, and the first light-emitting elements 1 and the second light-emitting elements 2 are arranged in each row and column. Place them alternately. In this manner, four second light emitting elements 2 are arranged closely around the first light emitting element 1 and four first light emitting elements 1 are arranged closely around the second light emitting element 2 . In this specification, when the planar shape of the light emitting element is substantially rectangular, the substantially rectangular means that the four corners are allowed to vary in angle of about 90±5°. Further, when the planar shape of the light emitting element is said to be substantially polygonal, the substantially polygonal shape means that the angle of each corner is allowed to fluctuate by about ±5°. In this specification, substantially parallel means that a variation of about ±5° from parallel is allowed.

In the light emitting device of Embodiment 1, when the first light emitting element 1 and the second light emitting element 2 are viewed from the circuit configuration side, each of the first light emitting element 1 and the second light emitting element 2 is arranged with, for example, light emitting elements. are arranged diagonally in a rectangular grid. Specifically, the first light-emitting elements 1 are arranged in odd-numbered rows in the diagonal direction, and the second light-emitting elements 2 are arranged in even-numbered rows in the diagonal direction. In other words, rows in which the first light emitting elements are arranged diagonally and rows in which the second light emitting elements are arranged in the diagonal direction are alternately arranged. Although there are two directions in the diagonal direction, in this specification, the odd-numbered and even-numbered rows in the diagonal direction refer to the planar shape of the first light-emitting element 1 or the connection between the adjacent second light-emitting elements 2 . diagonal columns
In the light-emitting device of Embodiment 1, by arranging the plurality of first light-emitting elements 1 and the plurality of second light-emitting elements 2 as described above, color mixing is enhanced and color unevenness is suppressed. This structure further enhances color mixing and suppresses color unevenness.
The light emitting device of Embodiment 1 will be described in detail below.

First, as shown in FIG. 3, the first wavelength conversion member 10 includes a transparent body 12 made of an inorganic material and having an upper surface and a lower surface, and a first phosphor layer 11 provided on the lower surface of the transparent body 12. and a first phosphor layer 11 is provided on the first light emitting element 1 so as to face the light emitting surface of the first light emitting element 1 respectively. The first phosphor layer 11 includes, for example, a translucent resin 11a and first phosphor particles 11b dispersed in the translucent resin 11a. Further, the second wavelength conversion member 20 includes, for example, a translucent sealing resin 22 and second phosphor particles 21 dispersed in the sealing resin 22 .

The first phosphor particles 11b are excited by the first light emitted by the first light emitting element 1 and emit light having a wavelength different from that of the first light. The second phosphor particles 21 are excited by the second light emitted by the second light emitting element 2 and emit light having a wavelength different from that of the second light. Also, the second phosphor particles 21 may be excited by the first light emitted by the first light emitting element 1 to emit light having a wavelength different from that of the first and second lights.

In the light-emitting device of Embodiment 1 configured as described above, when the first light-emitting element 1, the first phosphor particles 11b, and the second phosphor particles 21 are excited by the first light, the first A first light emitting portion including two phosphor particles 21 is configured, and a second light emitting portion including the second light emitting element 2 and the second phosphor particles 21 is configured.

In the light-emitting device of Embodiment 1 configured as described above, the light from the first light-emitting portion including the first light-emitting element 1 and the light from the second light-emitting portion including the second light-emitting element 2 are mixed (color mixture). ), and emitted from the upper surface of the sealing resin 22 as light of a desired emission color. In other words, the light-emitting device of Embodiment 1 emits the first light emitted by the first light-emitting element 1, the second light emitted by the second light-emitting element 2, and the light emitted by the first phosphor particles 11b. , and the light emitted by the second phosphor particles 21 mix inside the sealing resin 22 that collectively covers the second light emitting element 2, the first light emitting element 1, and the first wavelength conversion member 10. is emitted from the upper surface of the sealing resin 22 as light of an emission color of .

Further, in the light emitting device of Embodiment 1, the substrate 30 has the first wiring 31 for supplying power to the first light emitting element 1 and the second wiring 32 for supplying power to the second light emitting element 2 . Thereby, it is possible to independently control the power supply to the first light emitting element 1 and the power supply to the second light emitting element 2, and the first light emitting portion and the second light emitting portion are configured to emit light of different colors. Thus, by controlling the current values of the first wiring 31 and the second wiring 32, it is possible to change the emission color of the light emitting device. This point will be described later in detail.

In the light emitting device of Embodiment 1 configured as described above, the first wavelength conversion member 10 is configured to include the transparent body 12 made of an inorganic material, and the first wavelength conversion member 10 including the transparent body 12 A sealing resin 22 is formed to cover the . As a result, the boundary between the inorganic material and the resin, that is, the side surface of the translucent body 12 serves as a light scattering surface, which improves the color mixing in the sealing resin 22 and allows the light to be emitted from the upper surface of the sealing resin 22 . Color unevenness of light can be effectively suppressed.

For example, the refractive index of inorganic materials generally differs greatly depending on the type of material compared to resins, and it is possible to select materials with various refractive indexes as the material for the translucent body 12 . Therefore, the refractive index difference between the inorganic material forming the translucent body 12 and the sealing resin 22 can be increased, and the reflectance of the side surfaces of the translucent body 12 can be increased. In addition, the first wavelength conversion member 10 is usually produced by forming a phosphor layer on one main surface of a large translucent body and then cutting it into individual first wavelength conversion members 10 . The cut surface, that is, the side surface of the first wavelength conversion member 10 is roughened and has a large light scattering ability.

Therefore, the first wavelength conversion member 10 is configured to include the transparent body 12 made of an inorganic material, and the sealing resin 22 is formed so as to cover the first wavelength conversion member 10 including the transparent body 12. The light-emitting device of Embodiment 1 can further improve the color-mixing property in the sealing resin 22, and can suppress color unevenness of the light emitted from the upper surface of the sealing resin 22. FIG.

Moreover, in the light-emitting device of Embodiment 1, the refractive index of the translucent body 12 is preferably higher than the refractive index of the sealing resin 22 . With this configuration, the angle of refraction emitted from the upper surface of the transparent body 12 becomes larger than the angle of incidence inside the transparent body 12, so that the first light and the first phosphor particles passing through the interior of the transparent body 12 The light emitted by 11b is spread and emitted from the upper surface of the translucent body 12 (the surface opposite to the surface on which the first phosphor layer 11 is formed), so that the color mixing can be further improved.

Also, the first wavelength conversion member 10 and the first light emitting element 1 are joined by a joining member 40, for example. 41, and fillet 41 preferably contains a light-reflecting filler. When the fillet 41 contains a light-reflecting filler, the light emitted from the side surface of the second light emitting element 2 can be reflected by the fillet 41 and used as excitation light for the second phosphor particles 21, thereby increasing the wavelength conversion efficiency. . In addition, if the joining member 40 has fillets 41 containing fillers that reflect light, the fillets 41 can reflect and scatter light, and color mixing can be further improved. Note that the bonding member 42 between the first wavelength conversion member 10 and the first light emitting element 1 excluding the fillet 41 is preferably thin as long as a practical bonding strength can be maintained.

The second wavelength conversion member 20 includes, for example, a translucent sealing resin 22 and second phosphor particles 21 dispersed in the sealing resin 22 . The second phosphor particles 21 are preferably unevenly distributed in the sealing resin 22 so that the density on the first light emitting element 1 side and the second light emitting element 2 side are high. For example, in the manufacturing process, if the second phosphor particles 21 are sedimented in the sealing resin 22 so that the densities on the first light emitting element 1 side and the second light emitting element 2 side are increased, the second phosphor particles 21 are unevenly distributed. The thickness of the portion where the phosphor particles 21 are unevenly distributed becomes substantially uniform, and the optical path length of the light passing through the portion where the second phosphor particles 21 are densely distributed becomes constant, so that the occurrence of color unevenness and yellow rings can be suppressed.

The first phosphor particles 11b included in the first phosphor layer 11 and the second phosphor particles 21 included in the second wavelength conversion member 20 may each contain two or more types of phosphor particles having different emission colors. preferable. As the first phosphor particles 11b to be contained in the first phosphor layer 11, two or more types of phosphor particles having different emission colors are appropriately selected, the content of each phosphor particle is appropriately set, and the second wavelength conversion is performed. By appropriately selecting two or more types of phosphor particles having different emission colors as the second phosphor particles 21 to be contained in the member 20 and appropriately setting the content of each phosphor particle, a desired emission color can be easily realized. can. For example, if the first phosphor layer 11 includes first red phosphor particles and first green phosphor particles, and the second wavelength conversion member 20 includes second red phosphor particles and second green phosphor particles, , a desired emission color on the black body locus can be easily realized.

In this case, the first red phosphor particles and the second red phosphor particles may be of the same phosphor material, or may be of different phosphor materials. Also, the first green phosphor particles and the second green phosphor particles may be made of the same phosphor material, or may be made of different phosphor materials. When the first red phosphor particles and the second red phosphor particles are made of the same phosphor material, and the first green phosphor particles and the second green phosphor particles are made of the same phosphor material, for example, the first wiring By controlling the current values of 31 and the second wiring 32, it is possible to reduce the change in color rendering even when the emission color of the light emitting device is changed.

Next, the circuit configuration of the light emitting device of Embodiment 1 will be described.
As described above, the upper surface of the substrate 30 has the first wiring 31 for supplying power to the first light emitting element 1 and the second wiring 32 for supplying power to the second light emitting element 2 .

As shown in FIG. 4, the first wiring 31 corresponds to the first light emitting element 1 to be mounted in the mounting area inside the frame 33, and is connected to the p-side electrode of the first light emitting element 1, respectively. It has a 1p-side land 31a and a first n-side land 31b to which the n-side electrode of the first light emitting element 1 is connected. The first wiring 31 within the mounting area is called a first inner wiring. In addition, the first wiring 31 has a positive first external connection land 31 e 1 and a negative first external connection land 31 e 2 outside the frame 33 . Furthermore, the first wiring 31 includes a first connection wiring 31c1 connecting between the first external connection land 31e1 and the start end of the first inner wiring, and a first connection wiring 31c1 connecting between the first external connection land 31e2 and the end of the first inner wiring. has a first connection wiring 31c2 for connecting the . In the first inner wiring, the first light emitting element 1 is connected except for the first p-side land 31a directly connected to the first connection wiring 31c1 and the first n-side land 31b directly connected to the first connection wiring 31c2. The first n-side land 31b and the first p-side land 31a are connected in series so that the plurality of first light emitting elements 1 are connected in series between the first external connection land 31e1 and the first external connection land 31e2 when 4, they are connected by wiring or wires formed on the upper surface of the substrate. Further, the first wiring 31 has a first protective element connection wiring 31p1 extending from the first connection wiring 31c1 to the connection portion with the start end of the first inner wiring on the side opposite to the first external connection land 31e1. A first protection element connection wiring 31p2 extends from the first connection wiring 31c2 to the connection portion with the end of the first inner wiring on the side opposite to the first external connection land 31e2. The tip portions of the first protection element connection wirings 31p1 and 31p2 are referred to as first protection element mounting portions 31p11 and 31p21, respectively.

In addition, the second wiring 32 is connected to the second p-side lands 32a to which the p-side electrodes of the second light-emitting elements 2 are respectively connected corresponding to the second light-emitting elements 2 to be mounted in the mounting area inside the frame 33. and a second n-side land 32b to which the n-side electrode of the second light emitting element 2 is connected. The second wiring 32 within the mounting area is called a second inner wiring. The second wiring 32 has a positive side second external connection land 32 e 1 and a negative side second external connection land 32 e 2 outside the frame 33 . The second wiring 32 includes a second connection wiring 32c1 connecting between the second external connection land 32e1 and the start end of the second inner wiring, and a second connection wiring 32c1 connecting between the second external connection land 32e2 and the end of the second inner wiring. It has a second connection wiring 32c2 that In the second inner wiring, the second light emitting element 2 is connected except for the second p-side land 32a directly connected to the second connection wiring 32c1 and the second n-side land 32b directly connected to the second connection wiring 32c2. The second n-side land 32b and the second p-side land 32a are connected in series so that the plurality of second light emitting elements 2 are connected in series between the second external connection lands 32e1 and the second external connection lands 32e2. 4, they are connected by wiring or wires formed on the upper surface of the substrate. Further, the second wiring 32 has a second protection element connection wiring 32p1 extending from the second connection wiring 32c1 to the connection portion with the start end of the second inner wiring on the side opposite to the second external connection land 32e1. A second protection element connection wiring 32p2 extends from the second connection wiring 32c2 to the connection portion with the terminal end of the second inner wiring on the side opposite to the second external connection land 32e2. The ends of the second protection element connection wirings 32p1 and 32p2 are referred to as second protection element mounting portions 32p11 and 32p21, respectively.

By connecting the first light emitting elements 1 between the first p-side land 31a and the first n-side land 31b of the first wiring 31 provided as described above, as shown in FIG. The element 1 is connected in series between the first external connection land 31e1 and the first external connection land 31e2 on the negative side.
If necessary, a protective element is mounted on the first protective element mounting portion 31p1, the cathode of the protective element is connected to the first protective element mounting portion 31p1, and the anode of the protective element is connected to the first protective element connection wiring 31p2. , the protection element can be connected in parallel to a series circuit (first series circuit) in which a plurality of first light emitting elements 1 are connected in series.

By connecting the second light emitting elements 2 between the second p-side land 32a and the second n-side land 32b of the second wiring 32, as shown in FIG. It is connected in series between the external connection land 32e1 and the second negative external connection land 32e2.
If necessary, a protective element is mounted on the second protective element mounting portion 32p1, the cathode of the protective element is connected to the second protective element mounting portion 32p1, and the anode of the protective element is connected to the second protective element connection wiring 32p2. , the protection element can be connected in parallel to a series circuit (second series circuit) in which a plurality of second light emitting elements 2 are connected in series.

As described above, by controlling the current values of the first series circuit in which the plurality of first light emitting elements 1 are connected in series and the second series circuit in which the plurality of second light emitting elements 2 are connected in series, , the emission color of the light emitting device as a whole can be changed (toned).
In the light-emitting device of Embodiment 1 described above, all the first light-emitting elements 1 are connected in series between the external connection land 31e1 and the first external connection land 31e2, and between the second external connection land 32e1 and the second external connection land 32e2 An example in which all the second light emitting elements 2 are connected in series has been described. However, the light emitting device of Embodiment 1 is not limited to this. The element 1 and the plurality of second light-emitting elements 2 are connected in series, and the series circuits in which the elements are connected in series are formed between the external connection land 31e1 and the first external connection land 31e2, and between the second external connection land 32e1 and the second external connection land 32e2. You may make it connect in parallel between.

For example, both the first light emitting element 1 and the second light emitting element 2 are blue light emitting elements, and the first phosphor layer 11 and the second wavelength conversion member 20 contain the same red phosphor particles excited by blue light. Consider a case where a light-emitting device containing green phosphor particles is constructed. In this light-emitting device, the first light-emitting portion including the first light-emitting element 1 emits red phosphor particles and green phosphor particles contained in the first phosphor layer 11 above the first light-emitting element 1 . In addition to the presence of the phosphor particles, the presence of the red phosphor particles and the green phosphor particles contained in the second wavelength conversion member 20 also reduces the color temperature. On the other hand, the emission color of the second light-emitting portion including the second light-emitting element 2 is substantially the red phosphor contained in the second wavelength conversion member 20 above the second light-emitting element 2. Only particles and green phosphor particles will be present, and the color temperature will be high. Therefore, in the light emitting device of this example, the current value of the first series circuit in which the plurality of first light emitting elements 1 are connected in series is equal to the current in the second series circuit in which the plurality of second light emitting elements 2 are connected in series. When the current value of the first series circuit is made smaller than the current value of the second series circuit, light of a high color temperature can be emitted. be able to. If both the current values of the first series circuit and the second series circuit are changed without changing the current value ratio of the current value of the second series circuit, the light intensity can be changed without changing the emission color. can be done.

Further, according to the light-emitting device of Embodiment 1, both the first light-emitting element 1 and the second light-emitting element 2 are blue light-emitting elements, and the first phosphor layer 11 and the second wavelength conversion member 20 emit blue light, respectively. By containing the same red phosphor particles and green phosphor particles that are excited by The color temperature of the included second light emitting unit can be set to about 6500K. Therefore, according to the light-emitting device of Embodiment 1, it is possible to provide a light-emitting device capable of changing the color temperature of the emitted light between 2700K and 6500K.

Embodiment 2.
In the light-emitting device of Embodiment 2, (a) the shape of the frame 53 is octagonal when viewed from the top, and (b) the shape of the frame 53 is octagonal. is different from the light-emitting device of Embodiment 1 in that the shape of a part of is changed. The light emitting device of Embodiment 2 is configured in the same manner as the light emitting device of Embodiment 1 except for the above (a) and (b).
Hereinafter, the light-emitting device of Embodiment 2 will be specifically described for the points that are different from the light-emitting device of Embodiment 1, and descriptions of the same configurations as those of the light-emitting device of Embodiment 1 will be omitted.

As described above, in the light emitting device of Embodiment 2, the frame body 53 is provided so as to have an octagonal top view shape, as shown in FIG. That is, the shape of the outer peripheral lower end 53a and the inner peripheral lower end 53b on the upper surface of the base 30 are octagonal, and the shape of the boundary 53c with the second wavelength conversion member 20 on the surface of the frame 53 is also octagonal. In the light-emitting device of Embodiment 2, the surface of the second wavelength conversion member 20 inside the boundary 53c serves as the light-emitting surface of the light-emitting device.

In addition, since the shape of the frame 53 is octagonal, a part of the first wiring and the second wiring, that is, the first wiring embedded in the frame 53 of the first wiring and the second wiring, is provided. The shape of a part of the wiring and the second wiring is different from that of the light emitting device of the first embodiment. Specifically, as shown in FIG. 7, the first connection wirings 51c1 and 51c2, the first protection element connection wirings 51p1 and 51p2, the second connection wirings 52c1 and 52c2, and the second protection element connection wirings 52p1 and 52p2 are connected to the frame. It is provided between the outer peripheral lower end 53a and the inner peripheral lower end 53b of the body 53 so as to be parallel to the outer peripheral lower end 53a and the inner peripheral lower end 53b. The first connection wirings 51c1 and 51c2, the first protection element connection wirings 51p1 and 51p2, the second connection wirings 52c1 and 52c2, and the second protection element connection wirings 52p1 and 52p2 embedded in the frame 53 may be , and bent at the corners of the octagonal frame 53 .

The light emitting device of Embodiment 2 configured as described above has the following advantages: The distance between the second light emitting element 2 provided along the inner peripheral lower end 53b of the frame 53 and the inner peripheral lower end 53b can be reduced. That is, since the frame body 33 is circular in the light-emitting device of Embodiment 1, when the light-emitting elements are arranged so that the centers of the light-emitting elements coincide with the lattice points of the rectangular lattice, all the light-emitting elements located on the outer periphery and the frame If an attempt is made to secure a certain amount of space from the lower end of the inner periphery of the body 33, the space between some of the light emitting elements and the lower end of the inner periphery becomes large. On the other hand, in the light-emitting device of Embodiment 2, the frame 53 is octagonal. The distance between the light emitting element and the inner circumference lower end 53b can be the same. Therefore, the distance between some of the light emitting elements and the inner circumference lower end 53b does not become large. Therefore, the light-emitting device of the second embodiment can have a smaller light-emitting surface than the light-emitting device of the first embodiment.

As described above, the light-emitting device of Embodiment 2 can reduce the light-emitting surface of the light-emitting device, so that the luminous flux density can be increased when the types and number of light-emitting elements are the same. For example, light from the light emitting device can be efficiently used in a lamp such as a lighting device configured using the light emitting device of Embodiment 2 (capture efficiency can be improved).
Further, since the light-emitting device of Embodiment 2 can increase the luminous flux density, it is possible to improve the light condensing performance of a lamp using the light-emitting device of Embodiment 2, for example.

Further, in the light emitting device of Embodiment 2, as described above, the distance between the light emitting elements arranged along the inner peripheral lower end 53b and the inner peripheral lower end 53b can be the same. Therefore, it is possible to suppress color unevenness in the peripheral portion of the light-emitting surface that may occur due to an increase in the distance between some of the light-emitting elements and the inner peripheral lower end 53b. Therefore, the light-emitting device of Embodiment 2 can more effectively suppress color unevenness.

In FIG. 6 relating to the light emitting device of Embodiment 2, the top view shape of the frame 53 is a regular octagon, but in the light emitting device of Embodiment 2, the top view shape of the frame 53 is a regular octagon. is not limited to Considering the arrangement of the light emitting elements, for example, the top view shape of the frame 53 is inclined at an angle of 45 degrees in the row direction or the column direction so that the distance between the light emitting elements and the inner peripheral lower end 53b becomes more uniform. It may be an octagon whose side length is longer than the side length in the row direction or the column direction.

Hereinafter, each configuration, constituent materials, and the like in the embodiment will be described.

(First phosphor particles and second phosphor particles)
The first phosphor particles and the second phosphor particles (hereinafter simply referred to as phosphor particles) are excited by at least part of the light emitted by the light emitting element and emit fluorescence of a wavelength different from the emission wavelength of the light emitting element. Consists of body material.

For example, when blue light emitting elements are used as the first light emitting element 1 and the second light emitting element 2, a yellow phosphor material that emits yellow light when excited by blue light and a yellow phosphor material that emits yellow light when excited by blue light are used as phosphor materials. White light can be emitted by using a red phosphor material that emits red light.

As specific phosphor materials, for example, yellow to green phosphors include, for example, yttrium-aluminum-garnet-based phosphors (YAG-based phosphors) and lutetium-aluminum-garnet-based phosphors (LAG-based phosphors). can be used. As green phosphors, for example, chlorosilicate phosphors and β-sialon phosphors can be used. Examples of red phosphors include SCASN phosphors such as (Sr, Ca)AlSiN ₃ :Eu, CASN phosphors such as CaAlSiN ₃ :Eu, SrAlSiN ₃ :Eu phosphors, and K ₂ SiF ₆ :Mn phosphors. A KSF-based phosphor or the like can be used.

For example, for illumination, blue light emitting elements are used as the first light emitting element 1 and the second light emitting element 2, two kinds of phosphors, YAG phosphor and SCASN phosphor, are used as the first phosphor particles, and the second When a YAG-based phosphor is used as the phosphor particles, the color temperature of the first light emitting section including the first light emitting element 1 is about 2700K, and the color temperature of the second light emitting section including the second light emitting element 2 is about 6500K. By mixing these colors, a light-emitting device capable of emitting light of about 2700 to 6500K can be obtained.

(Phosphor layer)
The first phosphor layer 11 can be formed on the surface of the transparent body 12 by mixing a translucent material such as resin, glass, or inorganic substance as a phosphor binder. The first phosphor layer 11 may be a single layer containing one type of phosphor particles, or may be a single layer containing two or more types of phosphor particles. Also, the first phosphor layer 11 may be a laminate of a layer containing one type of phosphor particles and a layer containing the same or different phosphor particles as the layer. Moreover, the first phosphor layer 11 may contain a diffusion material as necessary. Furthermore, the first phosphor layer 11 is preferably formed to have a larger area than the top surface of the first light emitting element 1. In this case, the first phosphor layer 11 is formed so that the first phosphor layer 11 surrounds the top surface of the light emitting element. It is preferable to arrange the layer 11 on the first light emitting element 1 so that the surface of the layer 11 is annularly exposed.

The first phosphor layer 11 is formed, for example, by printing on the surface of the translucent body 12 . Here, the first phosphor layer 11 in this embodiment includes not only the case where the phosphor layer is in direct contact with the surface of the transparent body 12, but also the case where the phosphor layer is joined via another member such as an adhesive. be Bonding of the first phosphor layer 11 to the surface of the translucent body 12 includes, for example, pressure bonding, fusion bonding, sintering, bonding with an organic adhesive, and bonding with an inorganic adhesive such as low-melting glass. can. As a method for forming the first phosphor layer 11, in addition to the printing method, a compression molding method, a phosphor electrodeposition method, a phosphor sheet method, or the like can be used. In the printing method, a phosphor layer is formed by preparing a paste containing a phosphor, a binder, and a solvent, applying the paste to the surface of the translucent body, and drying the paste. As the binder, organic resin binders such as epoxy resins, silicone resins, phenol resins, and polyimide resins, and inorganic binders such as glass can be used. The compression molding method is a method of molding a phosphor layer material, which is a binder containing a phosphor, on the surface of a translucent body with a mold. In phosphor electrodeposition, a conductive thin film that can be made translucent is formed on the surface of a translucent material, and electrophoresis is used to deposit a charged phosphor on the thin film. It is a method to let The phosphor sheet method uses a phosphor sheet made by kneading a phosphor into a silicone resin and processing it into a sheet. Although any amount is acceptable, a phosphor sheet of about 200 μm or less is pressure-bonded to the translucent body to integrate them.

Here, the thickness of the first phosphor layer 11 is set to be, for example, 0.2 to 1.5 times, preferably 0.5 to 1 times the thickness of the translucent body. Also, the thickness of the first phosphor layer 11 is preferably 35 to 200 μm, more preferably 80 to 150 μm. When the thickness of the first phosphor layer 11 is thicker than 200 μm, the heat dissipation tends to be lowered. From the viewpoint of heat dissipation, the thinner the phosphor layer is, the better. In consideration of this point, the thickness is adjusted to an appropriate value.

(Transparent body)
The translucent body 12 is a member provided separately from the phosphor layer containing the phosphor, and is a member that supports the first phosphor layer 11 formed on the surface thereof. A plate-shaped body made of an inorganic material such as glass can be used for the transparent body 4 . Glass can be selected from, for example, borosilicate glass and quartz glass. The thickness of the translucent body 4 may be any thickness as long as the mechanical strength does not decrease during the manufacturing process and sufficient mechanical strength can be imparted to the phosphor layer 3 . It is preferable that the outer shape of the translucent body 12 is larger than the outer shape of the light emitting element. In this way, when the phosphor layer is formed over the entire main surface of the transparent body and the first phosphor layer 11 is placed so as to face the top surface of the light emitting element, there is some deviation in mounting accuracy. Even so, the phosphor layer can be reliably arranged over the entire upper surface of the light emitting element. Further, the translucent body 12 may contain a diffusing material. By doing so, it is possible to suppress color unevenness that may occur when the phosphor density of the first phosphor layer 11 is lowered by the diffusion material. Titanium oxide, barium titanate, aluminum oxide, silicon oxide, or the like can be used as the diffusing material. Moreover, the side surface of the translucent body 12 is preferably a rough surface. If the side surface of the translucent body 12 is rough, that is, if the side surface of the translucent body 12 has unevenness, the side surface can scatter the light from the second light emitting element 2, for example, thereby improving color mixing. It is possible to effectively suppress color unevenness in the light emitting device as a whole. Further, in this case, if the translucent body 12 contains a diffusing material, it is possible to more effectively suppress the color unevenness of the light emitting device as a whole. Furthermore, the upper surface of the translucent body 4, which is the light emitting surface, is not limited to a flat surface, and may have fine irregularities. This makes it possible to promote scattering of light emitted from the light-emitting surface and further suppress unevenness in luminance and color.

(joining member)
The bonding member 40 is required to have translucency so as to effectively guide the light emitted from the first light emitting element 1 to the first phosphor layer 11 . For example, as the translucent joining member 40, organic resins such as epoxy resins, silicone resins, phenol resins, and polyimide resins can be given as specific examples, and silicone resins are preferable. The thickness of the bonding member 42 between the first light emitting element 1 and the first phosphor layer 11 is preferably as thin as possible. When the thickness of the bonding member 42 is thin, the heat dissipation is improved, the transmission loss of light can be reduced, and the luminous efficiency of the light emitting device can be increased.

The bonding member 40 preferably exists not only between the first light emitting element 1 and the first phosphor layer 11 but also on the side surface of the first light emitting element 1 to form a fillet 41 . The fillet 41 reflects the light emitted from the side surface of the first light emitting element 1 to enter the first phosphor layer 11 , thereby improving the wavelength conversion efficiency of the first phosphor layer 11 . Furthermore, as described above, reflecting the light from the second light emitting element 2 by the fillet 41 contributes to the improvement of color mixing. Here, the fillet refers to a portion having a triangular cross-section that decreases downward from the light emitting element side. This fillet 41 can be formed by adjusting the amount of the bonding material when bonding the first light emitting element 1 and the first phosphor layer 11 . Moreover, when a silicone resin is used as the binder for the first phosphor layer 11 , it is preferable to use the silicone resin for the bonding member 40 as well. Since the refractive index difference between the first phosphor layer 11 and the bonding member 40 can be reduced, the incident light to the first phosphor layer 11 can be increased.

(sealing resin)
The sealing resin 22 is preferably made of a material that has electrical insulation properties, is capable of transmitting light emitted from the light emitting element, and has fluidity before solidification. A light-transmitting resin having a light transmittance of 70% or more is preferably selected as the sealing resin. Examples of light-transmitting resins include silicone resins, silicone-modified resins, epoxy resins, phenol resins, polycarbonate resins, acrylic resins, TPX resins, polynorbornene resins, and hybrid resins containing one or more of these resins. . Among them, silicone resins are preferable because they are excellent in heat resistance and light resistance, and exhibit little volume shrinkage after solidification.
In addition to the second phosphor particles, the sealing resin 22 may further contain additives such as fillers and diffusing agents. For example, SiO ₂ , TiO ₂ and the like can be used as diffusion materials.

(Substrate 30)
The substrate 30 has the first light emitting element 1 and the second light emitting element 2 and, if necessary, a protective element or the like arranged thereon. 33 are provided. The substrate 30 is formed in a rectangular plate shape, for example, as shown in FIGS. 1 and 2, and the size of the substrate 30 is appropriately set according to the number of light emitting elements to be arranged, the purpose, and the application.

As the material of the substrate 30, it is preferable to use an insulating material, and it is preferable to use a material that does not easily transmit light emitted from a light emitting element or the like, external light, or the like.
Specific examples include ceramics (Al ₂ O ₃ , AlN, etc.), or resins such as phenol resin, epoxy resin, polyimide resin, BT resin, polyphthalamide (PPA), and the like. A reflective member may be provided on the light emitting element mounting surface in order to enhance light reflectivity. The reflective member is, for example, kneaded with reflective particles such as TiO2 and an organic or inorganic binder. So-called white resist, white ink, ceramic ink, etc. correspond to this. As the organic binder, it is particularly preferable to use a silicone resin that is excellent in heat resistance and light resistance. Thereby, light can be reflected on the surface of the base, and a light emitting device with high light extraction efficiency can be obtained.

(first and second wiring)
As described above, the first wiring and the second wiring (hereinafter simply referred to as wiring) are electrically connected to the plurality of light emitting elements provided on the substrate and to the protection element provided as necessary, and It is for applying voltage from the power supply. The wiring is made of, for example, a metal member, and the material of the metal member is not particularly limited. Metals or alloys containing Ni, Au, Cu, Ag, Pd, Rh, Pt, Sn, etc. as main components can be used. Further, the wiring can be formed by vapor deposition, sputtering, printing, or the like, and plating or the like can be formed thereon. Moreover, from the viewpoint of less deterioration and adhesion with the joining member, it is preferable to form a metal containing Au as a main component on the outermost surface of the wiring by plating or the like. The thickness of the wiring is not particularly limited, and is appropriately set in consideration of the number of light emitting elements to be mounted, input power, and the like.
Since the first wiring 31 and the second wiring 32 are formed on the upper surface of the substrate 30, the second wiring 32 is separated between the first wirings 31 using a wire as necessary. It is possible to make a straddle connection or to straddle the first wiring 31 between the separated second wirings 32 .

(First and second light emitting elements)
The first light emitting element 1 and the second light emitting element 2 (hereinafter simply referred to as light emitting elements) are semiconductor elements that emit light when a voltage is applied.
Each of the light emitting elements may have, for example, a substantially rectangular planar shape or a polygonal shape such as a substantially hexagonal shape as shown in FIG. In addition, the emission wavelength of the light emitting element may be selected from the application, the excitation wavelength of the first phosphor particles 11b included in the first phosphor layer 11, the excitation wavelength of the second phosphor particles 21 included in the second wavelength conversion member 20, and the like. is appropriately selected in consideration of For example, blue (430 nm to 490 nm wavelength) and green (490 nm to 570 nm wavelength) light emitting elements can be made of ZnSe, nitride semiconductors, GaP, or the like. GaAlAs, AlInGaP, or the like can be used as a red light emitting element (wavelength: 620 nm to 750 nm). For the light emitting device of Embodiment 1, for example, when configuring a white light emitting device, it is preferable to use, for example, a blue light emitting element of a nitride semiconductor. Further, the light-emitting element is not limited to one that emits light in the visible light region, and an element that emits ultraviolet light or infrared light can also be selected.

The first light emitting element 1 and the second light emitting element 2 may be composed of light emitting elements having the same emission wavelength, or may be composed of different types of light emitting elements having different emission wavelengths, for example.
Further, in the light emitting device of the embodiment, an example in which the same number of the first light emitting elements 1 and the second light emitting elements 2 are used is shown, but the light emitting device of the embodiment is not limited to this. The numbers of light emitting elements 1 and second light emitting elements 2 may be different. In general, when an LED is used as a light emitting element, the lower the color temperature, the lower the luminous efficiency. Therefore, for example, when the color temperature of the second light emitting unit is lower than that of the first light emitting unit, the number of the first light emitting elements 1 is made larger than the number of the second light emitting elements 2 to adjust the balance between brightness and luminous efficiency. You may Also, in the case of changing (toning) the emission color in a minute lighting area, by reducing the number of elements on the side that does not require brightness, the number of elements on the other side can be increased. Thereby, the brightness and luminous efficiency of the light emitting device can be improved.

(Frame body 33)
It is preferable that the frame 33 is made of, for example, an insulating resin containing a light reflecting member. As the insulating resin, for example, a thermosetting resin, a thermoplastic resin, or the like can be used. More specifically, phenol resin, epoxy resin, BT resin, PPA, silicone resin and the like can be used. When a non-light-emitting device such as a protective element is mounted on the substrate, it is preferable to embed it in the light-reflecting resin because it causes light absorption. The frame 33 can be formed by, for example, a drawing method while discharging resin with a dispenser, a resin printing method, transfer molding, compression molding, or the like. A frame is formed so as to surround the second wavelength conversion member. By providing the frame, when the second wavelength conversion member is formed by coating, variation in the shape of the second wavelength conversion member in top view can be suppressed. That is, when the uncured second wavelength conversion member is applied to the inside of the frame, the uncured second wavelength conversion member flows inside the frame, but the frame prevents the second wavelength conversion member. By enclosing, the second wavelength conversion member can be suppressed from flowing outside the frame. As a result, variations in the shape of the second wavelength conversion member when viewed from above can be suppressed.

1 First Light Emitting Element 2 Second Light Emitting Element 10 First Wavelength Conversion Member 11 First Phosphor Layer 11a Translucent Resin 11b First Phosphor Particle 12 Translucent Body 20 Second Wavelength Conversion Member 21 Second Phosphor Particle 22 Sealing resin 30 Substrate 31 First wiring 31a First p-side land 31b First n-side land 31e1, 31e2 First external connection land 31c1, 31c2, 51c1, 51c2 First connection wiring 31p11, 31p21 First protection element mounting portion 31p1, 31p2 , 51p1, 51p2 First protection element connection wiring 32 Second wiring 32a Second p-side land 32b Second n-side land 32e1, 32e2 Second external connection land 32c1, 32c2, 52c1, 52c2 Second connection wiring 32p11, 32p21 Second protection element Mounting portion 32p1, 32p2, 52p1, 52p2 Second protection element connection wiring 32p11, 32p21, 52p11, 52p21 Second protection element mounting portion 33 Frame 40 (42) Joining member 41 Fillet

Claims (16)

a substrate;
a frame provided on the upper surface of the base so as to surround a mounting area;
a plurality of first light emitting elements provided in the mounting area;
a plurality of second light emitting elements provided in the mounting area;
A transparent body made of an inorganic material having an upper surface and a lower surface, and a first phosphor layer provided on the lower surface of the transparent body. First wavelength converters provided on the first light emitting elements a member;
a second wavelength conversion member provided on the base inside the frame so as to cover the second light emitting element and the first wavelength conversion member, the second wavelength conversion member comprising a sealing resin and second phosphor particles;
including
the side surface of the translucent body has unevenness,
The plurality of first light emitting elements and the plurality of second light emitting elements are arranged in rows and columns,
A light-emitting device, wherein the first light-emitting elements and the second light-emitting elements are alternately arranged in each of the rows and columns . 2. The light emitting device according to claim 1, wherein the side surface of said first wavelength conversion member is a rough surface. The first wavelength conversion member and the first light emitting element are joined by a joining member, the joining member has a fillet covering at least part of a side surface of the first light emitting element, and the fillet transmits light. 3. A light emitting device according to claim 1 or 2, comprising a reflective filler. 4. The light-emitting device according to claim 1, further comprising a reflecting member on the upper surface of said base. The upper surface of the base includes a first wiring that supplies power to the plurality of first light emitting elements and a second wiring that supplies power to the plurality of second light emitting elements,
The first wiring includes a positive-side first external connection land and a negative-side first external connection land located outside the frame, and the positive-side first external connection land and the negative-side first external connection land. a first inner wiring provided between connection lands and positioned inside the frame;
The second wiring includes a positive-side second external connection land and a negative-side second external connection land located outside the frame, and the positive-side second external connection land and the negative-side second external connection land. a second inner wiring provided between the connection lands and located inside the frame;
The light-emitting device according to any one of claims 1 to 4. a first series circuit in which the plurality of first light emitting elements are connected in series between the first external connection land on the positive side and the first external connection land on the negative side;
a second series circuit in which the plurality of second light emitting elements are connected in series between the positive side second external connection land and the negative side second external connection land;
wherein the first series circuit and the second series circuit are connected in parallel,
The light emitting device according to claim 5. The first wiring is
a first connection wiring connecting between the first outer connection land on the positive side and the start end of the first inner wiring; a first protection element connection wiring extending on the side opposite to the external connection land;
a first connection wiring connecting between the first outer connection land on the negative side and the terminal end of the first inner wiring; a first protection element connection wiring extending on the side opposite to the external connection land;
The light emitting device according to claim 5 or 6, comprising: the second wiring,
a second connection wiring connecting between the positive second outer connection land and the starting end of the second inner wiring; a second protection element connection wiring extending on the side opposite to the external connection land;
a second connection wiring connecting between the second outer connection land on the negative side and the terminal end of the second inner wiring; a second protection element connection wiring extending on the side opposite to the external connection land;
The light-emitting device according to any one of claims 5 to 7, having The first light emitting element and the second light emitting element are arranged so that their centers respectively coincide with lattice points of a rectangular lattice,
The light emitting device according to any one of claims 1 to 8, wherein the frame has an octagonal shape. The light-emitting device according to any one of claims 1 to 9, wherein the second phosphor particles are unevenly distributed in the sealing resin so that the density on the first light-emitting element side and the second light-emitting element side are high. . The first phosphor layer of the first wavelength conversion member includes first red phosphor particles and first green phosphor particles, and the second phosphor particles contained in the second wavelength conversion member are second red phosphor particles. The light-emitting device according to any one of claims 1 to 10, comprising body particles and second green phosphor particles. 12. The first red phosphor particles and the second red phosphor particles are made of the same phosphor material, and the first green phosphor particles and the second green phosphor particles are made of the same phosphor material. The light-emitting device according to . The first light emitting element and the second light emitting element each have a substantially rectangular shape, and the plurality of first light emitting elements and the plurality of second light emitting elements are each arranged in a diagonal direction of the substantially rectangular shape, The light emitting device according to any one of claims 1 to 12, wherein columns in which the first light emitting elements are diagonally arranged and columns in which the second light emitting elements are diagonally arranged are alternately arranged. . The light-emitting device according to any one of claims 1 to 13, wherein the transparent body has a higher refractive index than the sealing resin. The light emitting device according to any one of claims 1 to 14, wherein the thickness of the first phosphor layer is 0.2 to 1.5 times the thickness of the translucent body. The light emitting device according to any one of claims 1 to 15 , wherein the first phosphor layer has a thickness of 35 to 200 µm.

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