JP2019016780A - Light-emitting device - Google Patents

Abstract

To provide a light-emitting device which enables the enhancement in mixed color property and the reduction in the color unevenness in emitted light.SOLUTION: A light-emitting device comprises: a substrate; a first light-emitting element provided on the substrate; a second light-emitting element provided on the substrate; a translucent body having upper and lower faces and made of an inorganic material; a first phosphor layer provided on the lower face of the translucent body; a first wavelength conversion member provided over the first light-emitting element; and a second wavelength conversion member provided over the substrate so as to cover the second light-emitting element and the first wavelength conversion member, and including a sealing resin and second phosphor particles.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a light emitting device.

  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 in which a yellow phosphor is mixed. It is disclosed (FIG. 9 of Patent Document 1, Embodiment 3). According to Patent Document 1, the light emitting device of Patent Document 1 is improved in color mixing properties and can reduce color unevenness of emitted light.

JP 2013-120812 A

  However, in recent years, there has been a demand for a light emitting device that can further improve color mixing properties and can further reduce color unevenness of emitted light.

  Therefore, an object of the present invention is to provide a light-emitting device that can further improve color mixing properties and can further reduce color unevenness of emitted light.

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

  The light emitting device according to an embodiment of the present invention can further improve the color mixing property and can further reduce the color unevenness of the emitted light.

2 is a top view of the light emitting device according to Embodiment 1. FIG. It is sectional drawing about the AA line of FIG. It is sectional drawing which expands and shows a part of FIG. 3 is a top view of a base body 30. FIG. 4 is a diagram illustrating a circuit configuration of a first light emitting element and a second light emitting element in the light emitting device of Embodiment 1. FIG. 6 is a top view of a light emitting device according to Embodiment 2. FIG. 3 is a top view of a base body 60. FIG.

Hereinafter, the light emitting device of the embodiment will be described.
The light emitting device described below is for embodying the technical idea of the present disclosure, and the present disclosure is not limited to the following unless otherwise specified.
Embodiment 1. FIG.
As shown in FIGS. 1 and 2, the light emitting device of Embodiment 1 includes a base body 30, a plurality of first light emitting elements 1 provided on the base body 30, and a plurality of second light emitting elements provided on the base body 30. A base so as to collectively cover the element 2, the first wavelength conversion member 10 provided on the first light emitting element 1, and the second light emitting element 2, the first light emitting element 1, and the first wavelength conversion member 10, respectively. 30 and a second wavelength conversion member 20 provided on 30.

  In the light emitting device of the first embodiment, the base 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 base 30. . The wiring provided on the upper surface of the base 30 includes a first wiring 31 that supplies power to the first light emitting element 1 and a second wiring 32 that supplies power to the second light emitting element 2. In addition, a frame 33 is provided on the upper surface of the base body 30 so as to surround a mounting region in which the first light emitting element 1 and the second light emitting element 2 are mounted. Then, on the upper surface of the base body 30, a plurality of first light emitting elements 1 and a plurality of second light emitting elements 2 are provided in the mounting region inside the frame 33 in the following arrangement.

  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 when viewed from above are polygonal shapes such as a substantially rectangular shape. For example, the first light-emitting element 1 or the second light-emitting element 2 is arranged so that the center thereof coincides with the lattice point of the rectangular lattice, in other words, substantially parallel to one opposite side of the two opposite sides of the rectangular lattice. Are arranged side by side in such a direction that they are arranged side by side in a direction substantially parallel to the opposite side. In this specification, light emitting elements arranged in a direction substantially parallel to one opposite side of the rectangular lattice are referred to as rows, and light emitting elements arranged in a direction substantially parallel to the other opposite side are referred to as columns. In the light emitting device of the first embodiment, the first light emitting element 1 and the second light emitting element 2 are arranged in rows or columns, and the first light emitting element 1 and the second light emitting element 2 are further arranged in each row and column, respectively. Place them alternately. In this manner, the four second light emitting elements 2 are arranged in the vicinity of the first light emitting element 1, and the four first light emitting elements 1 are arranged in the vicinity of the second light emitting element 2. In this specification, when the planar shape of the light-emitting element is a substantially rectangular shape, a substantially rectangular shape means that a change in angle of which the corners of the four corners are about 90 ± 5 ° is allowed. Further, the substantially polygonal shape when the planar shape of the light-emitting element is a substantially polygonal shape means that the angle of each corner is allowed to vary by about ± 5 °. In this specification, “substantially parallel” means that a variation of about ± 5 ° from parallel is allowed.

In the light emitting device according to the first embodiment, when the first light emitting element 1 and the second light emitting element 2 are viewed from the circuit configuration surface, the first light emitting element 1 and the second light emitting element 2 are, for example, arranged with light emitting elements. Are arranged in a diagonal direction of a rectangular lattice. Specifically, the first light emitting elements 1 are arranged in odd rows in the diagonal direction, and the second light emitting elements 2 are arranged in even rows in the diagonal direction. That is, the rows in which the first light emitting elements are arranged in the diagonal direction and the 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 columns in the diagonal direction are connected between the planar shape of the first light emitting element 1 or the second light emitting element 2 between adjacent ones. Is a diagonal row.
The light-emitting device of Embodiment 1 arranges the plurality of first light-emitting elements 1 and the plurality of second light-emitting elements 2 as described above, thereby improving color mixing and suppressing color unevenness, as will be described later. It is configured to further improve color mixing and suppress color unevenness.
Hereinafter, the light-emitting device of Embodiment 1 will be described in detail.

  First, as shown in FIG. 3, the first wavelength conversion member 10 includes a light transmitting body 12 made of an inorganic material having an upper surface and a lower surface, and a first phosphor layer 11 provided on the lower surface of the light transmitting body 12. The 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. Moreover, the 2nd wavelength conversion member 20 contains the 2nd fluorescent substance particle 21 disperse | distributed in the sealing resin 22 which has translucency, and the sealing resin 22, for example.

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

  In the light emitting device of the first embodiment configured as described above, when the first light emitting element 1, the first phosphor particle 11b, and the second phosphor particle 21 are excited by the first light, the first light emitting device 1, the first phosphor particle 11b, and the second phosphor particle 21 are further excited. The 1st light emission part containing the 2 fluorescent substance particle 21 is comprised, and the 2nd light emission part containing the 2nd light emitting element 2 and the 2nd fluorescent substance particle 21 is comprised.

  In the light emitting device of the first embodiment configured as described above, the light of the first light emitting unit including the first light emitting element 1 and the light of the second light emitting unit including the second light emitting element 2 are mixed (color mixing). ), And is 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 includes the first light emitted from the first light-emitting element 1, the second light emitted from the second light-emitting element 2, and the light emitted from the first phosphor particles 11b. The light emitted from the second phosphor particles 21 is mixed in 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 the emission color.

  In the light emitting device of the first embodiment, the base body 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. Thereby, it is possible to control independently the electric power feeding to the 1st light emitting element 1, and the electric power feeding to the 2nd light emitting element 2, and it comprises so that the light emission color of a 1st light emission part and a 2nd light emission part may differ. Thus, by controlling the current values of the first wiring 31 and the second wiring 32, the light emission color of the light emitting device can be changed. This point will be described later in detail.

  In the light emitting device according to the first embodiment configured as described above, the first wavelength conversion member 10 is configured to include the light transmitting body 12 made of an inorganic material, and the first wavelength conversion member 10 including the light transmitting body 12 is included. A sealing resin 22 is formed so as to cover the surface. Thereby, the boundary between the inorganic material and the resin, that is, the side surface of the light transmitting body 12 becomes a light scattering surface, and the color mixing property in the sealing resin 22 can be improved and emitted from the upper surface of the sealing resin 22. The uneven color of light can be effectively suppressed.

  For example, the refractive index of an inorganic material generally differs greatly depending on the type of material compared to a resin, and the light transmitting body 12 can be selected from materials having various refractive indexes. Therefore, the refractive index difference between the inorganic material constituting the light transmitting body 12 and the sealing resin 22 can be increased, and the reflectance of the side surface of the light transmitting body 12 can be increased. In addition, the first wavelength conversion member 10 is usually manufactured by forming a phosphor layer on one main surface of a large-sized translucent body and then cutting the individual first wavelength conversion members 10. The cut surface, that is, the side surface of the first wavelength conversion member 10 is a rough surface and can be a surface having a large light scattering ability.

  Therefore, the 1st wavelength conversion member 10 is comprised so that the transparent body 12 which consists of inorganic materials may be comprised, and the sealing resin 22 is formed so that the 1st wavelength conversion member 10 containing the transparent body 12 may be covered. The light emitting device according to the first embodiment can further improve the color mixing property in the sealing resin 22, and can suppress uneven color of light emitted from the upper surface of the sealing resin 22.

  In the light emitting device of Embodiment 1, it is preferable that the refractive index of the translucent body 12 is higher than the refraction of the sealing resin 22. In this case, since the refraction angle emitted from the upper surface of the translucent body 12 becomes larger than the incident angle inside the translucent body 12, the first light and the first phosphor particles passing through the translucent body 12 are used. The light emitted by 11b is 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), and the color mixing property can be further improved.

  Moreover, although the 1st wavelength conversion member 10 and the 1st light emitting element 1 are joined by the joining member 40, for example, the joining member 40 fills at least one part of the side surface of the 1st light emitting element 1 in this case. It is preferable that the fillet 41 includes a filler that reflects light. When the fillet 41 includes a filler that reflects light, the light emitted from the side surface of the second light emitting element 2 can be reflected by the fillet 41 and used as the excitation light of the second phosphor particles 21, and the wavelength conversion efficiency can be increased. . Moreover, when the joining member 40 has the fillet 41 containing the filler which reflects light, light can be reflected and scattered by the fillet 41, and color mixing property can be improved more. The joining 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 practical joining 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 densities on the first light emitting element 1 side and the second light emitting element 2 side are increased. For example, in the manufacturing process, when the second phosphor particles 21 are settled 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 is increased, the second phosphor particles 21 are disposed. The thickness of the portion where the phosphor particles 21 are unevenly distributed becomes substantially uniform, the optical path length of the light passing through the high-density portion of the second phosphor particles 21 is constant, and the occurrence of uneven color and yellow ring 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 include 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 kinds of phosphor particles having different emission colors are appropriately selected, the contents of the respective phosphor particles are appropriately set, and the second wavelength conversion is performed. By appropriately selecting two or more kinds 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. it can. For example, when 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. The 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 the same phosphor material or different phosphor materials. Further, the first green phosphor particles and the second green phosphor particles may be the same phosphor material or different phosphor materials. When the first red phosphor particles and the second red phosphor particles are the same phosphor material, and the first green phosphor particles and the second green phosphor particles are the same phosphor material, for example, the first wiring By controlling the current value of 31 and the second wiring 32, the change in color rendering can be reduced even when the emission color of the light emitting device is changed.

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

  As shown in FIG. 4, the first wiring 31 is connected to the p-side electrode of the first light emitting element 1 corresponding to the first light emitting element 1 mounted in the mounting region inside the frame 33. The 1p side land 31a and the 1st n side land 31b to which the n side electrode of the 1st light emitting element 1 is connected are provided. The first wiring 31 in the mounting area is referred to as a first inner wiring. Further, the first wiring 31 has a positive first external connection land 31e1 and a negative first external connection land 31e2 outside the frame 33. Further, the first wiring 31 includes a first connection wiring 31c1 that connects between the first external connection land 31e1 and the start end of the first inner wiring, and a space between the first external connection land 31e2 and the end of the first inner wiring. The first connection wiring 31c2 is connected. 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 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. As shown in FIG. 4, they are connected by wires or wires formed on the upper surface of the substrate. The first wiring 31 has a first protection element connection wiring 31p1 extending from the first connection wiring 31c1 to the opposite side of the first external connection land 31e1 with respect to the connection portion with the start end of the first inner wiring. The first protection element connection wiring 31p2 extends from the first connection wiring 31c2 to the opposite side of the first external connection land 31e2 with respect to the connection portion with the terminal of the first inner wiring. The tip portions of the first protection element connection wires 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 land 32a to which the p-side electrode of the second light emitting element 2 is connected in correspondence with the second light emitting element 2 mounted in the mounting region 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 in the mounting area is referred to as a second inner wiring. The second wiring 32 has a positive second external connection land 32e1 and a negative second external connection land 32e2 outside the frame 33. The second wiring 32 connects the second connection wiring 32c1 that connects the second external connection land 32e1 and the start end of the second inner wiring, and the second external connection land 32e2 and the end of the second inner wiring. The second connection wiring 32c2 is provided. 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 so that the plurality of second light emitting elements 2 are connected in series between the second external connection land 32e1 and the second external connection land 32e2. As shown in FIG. 4, they are connected by wires 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 opposite side of the second external connection land 32e1 with respect to the connection portion with the start end of the second inner wiring. The second protective element connection wiring 32p2 extends from the second connection wiring 32c2 to the opposite side of the second external connection land 32e2 with respect to the connection portion with the terminal of the second inner wiring. The tip portions of the second protection element connection wires 32p1 and 32p2 are referred to as second protection element mounting portions 32p11 and 32p21, respectively.

By connecting the first light-emitting element 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 negative first external connection land 31e2.
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. By connecting to, a 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.

Further, by connecting the second light emitting element 2 between the second p-side land 32a and the second n-side land 32b of the second wiring 32, as shown in FIG. The external connection land 32e1 and the negative second external connection land 32e2 are connected in series.
If necessary, a protection element is mounted on the second protection element mounting portion 32p1, the cathode of the protection element is connected to the second protection element mounting portion 32p1, and the anode of the protection element is connected to the second protection element connection wiring 32p2. By connecting to, a 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, respectively. The emission color of the entire light emitting device can be changed (toned).
In the light emitting device of the first embodiment, 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. In the above description, all the second light emitting elements 2 are connected in series. However, the light-emitting device of Embodiment 1 is not limited to this. For example, the plurality of first light-emitting elements 1 and the plurality of second light-emitting elements 2 are divided into a plurality of groups, and the first light emission of each group. A series circuit in which the element 1 and the plurality of second light emitting elements 2 are connected in series and connected in series is connected between the external connection land 31e1 and the first external connection land 31e2, and the second external connection land 32e1 and the second external connection land 32e2. You may make it connect in parallel in between.

  For example, the first light-emitting element 1 and the second light-emitting element 2 are both blue light-emitting elements, and the same red phosphor particles that are excited by blue light on the first phosphor layer 11 and the second wavelength conversion member 20 respectively. Consider a case where a light emitting device containing green phosphor particles is configured. In this light-emitting device, the light emission color of the first light-emitting unit configured to include the first light-emitting element 1 is above the first light-emitting element 1 and the red phosphor particles contained in the first phosphor layer 11 and the green color. In addition to the presence of the phosphor particles, the red phosphor particles and the green phosphor particles contained in the second wavelength conversion member 20 are present, so that the color temperature is lowered. On the other hand, the emission color of the second light-emitting unit configured to include the second light-emitting element 2 is substantially above the second light-emitting element 2 and the red phosphor substantially included in the second wavelength conversion member 20. 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 value of the second series circuit in which the plurality of second light emitting elements 2 are connected in series. If the value is increased compared to the value, light having a low color temperature can be emitted, and if the current value of the first series circuit is reduced compared to the current value of the second series circuit, light having a high color temperature is emitted. be able to. Note that if the current value of the first series circuit is changed without changing the ratio of the current value to the second series circuit, the intensity of light can be changed without changing the emission color. Can do.

  Further, according to the light emitting device of the first embodiment, both the first light emitting element 1 and the second light emitting element 2 are blue light emitting elements, and blue light is respectively applied to the first phosphor layer 11 and the second wavelength conversion member 20. By including the same red phosphor particles and green phosphor particles excited by the above, for example, the color temperature of the first light emitting unit including the first light emitting element 1 can be set to about 2700 K, and the second light emitting element 2 is The color temperature of the second light emitting unit including the light emitting unit can be about 6500K. Therefore, according to the light emitting device of the first embodiment, it is possible to provide a light emitting device that can change the color temperature of the emitted color between 2700K to 6500K.

Embodiment 2. FIG.
In the light emitting device of the second embodiment, (a) the shape of the frame 53 in the top view is an octagon, and (b) the first wiring and the second wiring due to the shape of the frame 53 being an octagon. This is different from the light emitting device of Embodiment 1 in that a part of the shape 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 described specifically in terms of differences from the light-emitting device of Embodiment 1, and description of the same configuration as that of the light-emitting device of Embodiment 1 will be omitted.

  As described above, in the light emitting device of the second embodiment, the frame 53 is provided so that the top view shape is an octagon as shown in FIG. That is, the shape of the outer peripheral lower end 53 a and the inner peripheral lower end 53 b on the upper surface of the base body 30 are octagonal, and the shape of the boundary 53 c 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 is the light emitting surface of the light emitting device.

  In addition, since the shape of the frame 53 is an octagon, a part of the first wiring and the second wiring, that is, the first embedded in the frame 53 of the first wiring and the second wiring is provided. The shape of 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 framed. Between the outer periphery lower end 53a and the inner periphery lower end 53b of the body 53, it is provided so as to be parallel to the outer periphery lower end 53a and the inner periphery 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 are provided as necessary. And bent at the corners of the octagonal frame 53.

  The light emitting device according to the second embodiment configured as described above includes the distance between the first light emitting element 1 and the first wavelength conversion member 10 provided along the inner peripheral lower end 53b of the frame 53, and the inner peripheral lower end 53b, and The space | interval of the 2nd 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 made small. In other words, since the frame 33 is circular in the light emitting device of the first embodiment, when the light emitting element is arranged so that the center thereof coincides with the lattice point of the rectangular lattice, all the light emitting elements and the frame located on the outer peripheral portion are arranged. If an interval between the lower end of the body 33 and the inner peripheral lower end is to be secured above a certain level, the interval between some of the light emitting elements and the inner peripheral lower end increases. In contrast, in the light emitting device of the second embodiment, since the frame 53 is an octagon, when the light emitting elements are arranged so that the centers thereof coincide with the lattice points of the rectangular lattice, The distance between the light emitting element and the inner peripheral lower end 53b can be made the same. Therefore, the distance between some of the light emitting elements and the inner peripheral lower end 53b does not increase. Therefore, the light emitting device of Embodiment 2 can make the light emitting surface of the light emitting device smaller than the light emitting device of Embodiment 1.

Thus, since the light emitting device of Embodiment 2 can reduce the light emitting surface of the light emitting device, the light 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 an illumination device configured using the light-emitting device of Embodiment 2 (capturing efficiency can be improved).
In addition, since the light emitting device of the second embodiment can increase the light flux density, for example, it is possible to improve the light condensing performance in a lamp using the light emitting device of the second embodiment.

  In the light emitting device of the second embodiment, as described above, the distance between the light emitting element arranged along the inner peripheral lower end 53b and the inner peripheral lower end 53b can be made the same. For this reason, it is possible to suppress color unevenness in the peripheral portion of the light emitting surface that may be caused by 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 suppress color unevenness more effectively.

  In FIG. 6 related to the light emitting device of the second embodiment, the top view shape of the frame 53 is drawn in a regular octagon. In the light emitting device of the second embodiment, the top view shape of the frame 53 is a regular octagon. It is not limited to. Considering the arrangement of the light emitting elements and the like, 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. The length of the side may be an octagon longer than the length of the side in the row direction or the column direction.

  Hereinafter, each structure and its constituent materials 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 from the light emitting element and emit light having a wavelength different from the emission wavelength of the light emitting element. Made of body material.

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

As specific phosphor materials, for example, yellow to green phosphors include, for example, yttrium, aluminum, garnet phosphors (YAG phosphors) and lutetium, aluminum, garnet phosphors (LAG phosphors). Can be used. As the green phosphor, for example, a chlorosilicate phosphor and a β sialon phosphor 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. A KSF phosphor or the like can be used.

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

(Phosphor layer)
Examples of the first phosphor layer 11 include a material formed by mixing a light-transmitting material such as resin, glass, or inorganic substance as a binder of the phosphor and formed on the surface of the light-transmitting body 12. The first phosphor layer 11 may be a single layer including one kind of phosphor particles, or may be a single layer including two or more kinds of phosphor particles. The first phosphor layer 11 may be a layer in which a layer containing one kind of phosphor particles and a layer containing phosphor particles that are the same as or different from the layers are stacked. Moreover, the 1st fluorescent substance layer 11 may contain the diffusion material as needed. Furthermore, the first phosphor layer 11 is preferably formed to be larger than the area of the upper surface of the first light emitting element 1, and in this case, the first phosphor layer 11 is formed around the upper surface of the light emitting element. It is preferable to arrange on the first light emitting element 1 so that the surface of the layer 11 is exposed in an annular shape.

  For example, the first phosphor layer 11 is formed on the surface of the light transmitting body 12 by printing or the like. 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 translucent body 12 but also the case where the first phosphor layer 11 is joined through another member such as an adhesive. It is. Examples of the bonding of the first phosphor layer 11 to the surface of the transparent body 12 include pressure bonding, fusing, sintering, bonding with an organic adhesive, and bonding with an inorganic adhesive such as low melting glass. it 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 light transmitting body, and drying the paste. As the binder, an organic resin binder such as an epoxy resin, a silicone resin, a phenol resin, and a polyimide resin, or an inorganic binder such as glass can be used. The compression molding method is a method in which a phosphor layer material in which a phosphor is contained in a binder is molded on a surface of a translucent body with a mold. In the phosphor electrodeposition method, a conductive thin film that can be made translucent is formed on the surface of a light transmitting body, and charged phosphor is deposited on the thin film using electrophoresis. It is a method to make it. The phosphor sheet method uses a phosphor sheet obtained by kneading a phosphor into a silicone resin and processing it into a sheet shape. From the viewpoint of improving the heat dissipation from the phosphor, the thickness of the phosphor sheet is thin. Any method is possible, but it is a method in which a phosphor sheet of about 200 μm or less is bonded to a light transmitting body and integrated.

  Here, the thickness of the 1st fluorescent substance layer 11 is 0.2 times-1.5 times of the thickness of a translucent body, for example, Preferably, it sets to 0.5 times-1 time. Moreover, the thickness of the 1st fluorescent substance layer 11 becomes like this. Preferably, it is 35-200 micrometers, More preferably, it is 80-150 micrometers. When the thickness of the 1st fluorescent substance layer 11 is thicker than 200 micrometers, there exists a tendency for heat dissipation to fall. From the viewpoint of heat dissipation, the thinner the phosphor layer, the better. However, if the phosphor layer is too thin, the amount of phosphor decreases, so the chromaticity range of light emission to be obtained tends to be small. Considering this point, the thickness is adjusted to an appropriate thickness.

(Translucent 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-like body made of an inorganic material such as glass can be used for the translucent body 4. As the glass, for example, borosilicate glass or quartz glass can be selected. The thickness of the translucent body 4 only needs to be a thickness that can impart sufficient mechanical strength to the phosphor layer 3 without lowering the mechanical strength in the manufacturing process. The outer shape of the translucent body 12 is preferably larger than the size of the outer shape of the light emitting element. In this case, when the phosphor layer is formed on the entire main surface of the light transmitting body and the first phosphor layer 11 is placed facing the upper surface of the light emitting element, a slight shift in mounting accuracy occurs. However, the phosphor layer can be reliably disposed on the entire top surface of the light emitting element. Further, the light transmitting body 12 may contain a diffusing material. If it does in this way, it will become possible to suppress the color nonuniformity which may arise when the fluorescent substance density | concentration of the 1st fluorescent substance layer 11 is made low by a diffusion material. As the diffusion material, titanium oxide, barium titanate, aluminum oxide, silicon oxide, or the like can be used. Moreover, it is preferable that the side surface of the translucent body 12 is a rough surface. When the side surface of the translucent body 12 is rough, that is, when the side surface of the translucent body 12 has irregularities, the side surface can scatter, for example, light from the second light emitting element 2 and improve color mixing. Therefore, the color unevenness of the light emitting device as a whole can be effectively suppressed. In this case, when the light transmitting body 12 includes a diffusing material, it is possible to more effectively suppress the color unevenness of the entire light emitting device. Furthermore, the upper surface of the translucent body 4 serving as the light emitting surface is not limited to a flat surface, and may have fine irregularities. As a result, it is possible to further suppress luminance unevenness and color unevenness by promoting scattering of outgoing light from the light emitting surface.

(Joining member)
The bonding member 40 is required to have translucency capable of effectively guiding the emitted light from the first light emitting element 1 to the first phosphor layer 11. For example, specific examples of the light-transmitting bonding member 40 include organic resins such as an epoxy resin, a silicone resin, a phenol resin, and a polyimide resin, and a silicone resin is 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, heat dissipation is improved, light transmission loss can be reduced, and the light emission efficiency of the light emitting device can be increased.

  It is preferable that the bonding member 40 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 the fillet 41. The fillet 41 can reflect the outgoing light from the side surface of the first light emitting element 1 and enter the first phosphor layer 11 to improve the wavelength conversion efficiency of the first phosphor layer 11. Furthermore, as described above, the light from the second light emitting element 2 is reflected by the fillet 41, thereby contributing to the improvement of the color mixing property. Here, the fillet refers to a portion having a triangular cross section that decreases from the light emitting element side toward the lower portion. The fillet 41 can be formed by adjusting the amount of the joining member when joining the first light emitting element 1 and the first phosphor layer 11. Further, when a silicone resin is used as the binder of the first phosphor layer 11, it is preferable to use a silicone resin for the bonding member 40. 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 a material that has electrical insulation, is capable of transmitting light emitted from the light emitting element, and has fluidity before solidification. As the sealing resin, a light transmissive resin having a light transmittance of 70% or more is preferably selected. Examples of the light transmissive resin include silicone resins, silicone-modified resins, epoxy resins, phenol resins, polycarbonate resins, acrylic resins, TPX resins, polynorbornene resins, or hybrid resins containing one or more of these resins. . Among these, silicone resins are preferable because they are excellent in heat resistance and light resistance and have little volume shrinkage after solidification.
In addition to the second phosphor particles, the sealing resin 22 may further include additives such as a filler and a diffusing material. For example, examples of the diffusion material include SiO ₂ and TiO ₂ .

(Substrate 30)
The base body 30 is provided with the first light emitting element 1 and the second light emitting element 2, and protective elements as necessary, and has a first wiring 31 and a second wiring 32 on its upper surface, and further a frame body. 33 is provided. For example, as shown in FIGS. 1 and 2, the base 30 is formed in a rectangular flat plate shape, and the size of the base 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 base body 30, it is preferable to use an insulating material, and it is preferable to use a material that hardly transmits light emitted from a light emitting element or the like or external light.
Specific examples include ceramics (Al ₂ O ₃ , AlN, etc.), or resins such as phenol resin, epoxy resin, polyimide resin, BT resin, polyphthalamide (PPA). In order to enhance light reflectivity, a reflective member may be provided on the light emitting element mounting surface. The reflective member is, for example, a mixture of reflective particles such as TiO 2 and organic or inorganic binders. The so-called white resist, white ink, ceramic ink, and the like are applicable. As the organic binder, it is particularly preferable to use a silicone resin excellent in heat resistance and light resistance. As a result, light can be reflected from the surface of the substrate, 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 a plurality of light emitting elements provided on the substrate and protective elements provided as necessary, and are externally connected. The voltage is applied from the power source. The wiring is made of, for example, a metal member, and the material of the metal member is not particularly limited. For example, when the substrate 30 is made of ceramics, for example, the wiring material may be W, Mo, Ti, A metal or alloy containing Ni, Au, Cu, Ag, Pd, Rh, Pt, Sn or the like as a main component can be used. Further, the wiring can be further formed with plating or the like by vapor deposition, sputtering, printing, or the like. Moreover, it is preferable to form a metal mainly composed of Au on the outermost surface of the wiring by plating or the like from the viewpoint of little deterioration and adhesion with the joining member. 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.
In addition, since the 1st wiring 31 and the 2nd wiring 32 are formed in the upper surface of the base | substrate 30, the 2nd wiring 32 is provided between the 1st wiring 31 isolate | separated using the wire suitably as needed. It is possible to connect across the first wiring 31 or connect 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 voltage is applied.
Each of the light emitting elements may have, for example, a substantially rectangular shape or a polygonal shape such as a substantially hexagonal shape as shown in FIG. Further, the emission wavelength of the light emitting element is the use, 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 selected as appropriate. For example, as a blue (wavelength: 430 nm to 490 nm) and green (wavelength: 490 nm to 570 nm) light emitting element, ZnSe, a nitride semiconductor, GaP, or the like can be used. Further, GaAlAs, AlInGaP, or the like can be used as a red (wavelength: 620 nm to 750 nm) light emitting element. For example, when a white light-emitting device is configured with respect to the light-emitting device of Embodiment 1, for example, a blue light-emitting element of a nitride semiconductor is preferably used. The light emitting element is not limited to a light emitting element that emits light in the visible light region, and an element that emits ultraviolet light or infrared light can be selected.

The 1st light emitting element 1 and the 2nd light emitting element 2 may be comprised by the light emitting element with the same light emission wavelength, for example, may be comprised by the kind of light emitting element from which a light emission wavelength etc. differ.
Further, in the light emitting device of the embodiment, the 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 number of the light emitting elements 1 and the second light emitting elements 2 may be different. Generally, when an LED is used as the light emitting element, the light emission efficiency decreases as the color temperature decreases. For this reason, 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 of brightness and luminous efficiency. May be. Further, when the emission color is changed (toned) in the minute lighting region, the number of other elements can be increased by reducing the number of elements that do not require brightness. Thereby, the brightness and luminous efficiency of the light emitting device can be improved.

(Frame 33)
The frame 33 is preferably configured using, 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, a phenol resin, an epoxy resin, a BT resin, PPA, a silicone resin, etc. are mentioned. When a non-light-emitting device such as a protective element is mounted on a substrate, it becomes a cause of light absorption, so that it is preferably embedded in a light reflecting resin. The frame 33 can be formed by, for example, a method of drawing while discharging resin with a dispenser, a resin printing method, transfer molding, compression molding, or the like. The frame is formed so as to surround the second wavelength conversion member. By providing the frame body, when the second wavelength conversion member is formed by coating, variation in the shape of the second wavelength conversion member in a top view can be suppressed. That is, when the second wavelength conversion member before curing is applied to the inside of the frame body, the second wavelength conversion member before curing flows inside the frame body, but the frame body uses the second wavelength conversion member. By surrounding, it can suppress that the 2nd wavelength conversion member flows outside the frame. Thereby, the variation in the shape of the 2nd wavelength conversion member in the top view can be controlled.

DESCRIPTION OF SYMBOLS 1 1st light emitting element 2 2nd light emitting element 10 1st wavelength conversion member 11 1st fluorescent substance layer 11a Translucent resin 11b 1st fluorescent substance particle 12 Translucent body 20 2nd wavelength converting member 21 2nd fluorescent substance particle 22 Sealing resin 30 Base 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 part 32p1, 32p2, 52p1, 52p2 Second protection element contact Connection line 32p11, 32p21, 52p11, 52p21 Second protection element mounting part 33 Frame 40 (42) Joining member 41 Fillet

Claims (13)

A substrate;
A first light emitting element provided on the substrate;
A second light emitting element provided on the substrate;
A first wavelength conversion member provided on the first light emitting element, comprising: a light transmitting 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 light transmitting body. When,
A second wavelength conversion member provided on the base so as to cover the second light emitting element and the first wavelength conversion member, and comprising a sealing resin and second phosphor particles;
A light emitting device comprising:   The first wavelength conversion member and the first light emitting element are joined by a joining member, and the joining member has a fillet that covers at least a part of a side surface of the first light emitting element, and the fillet emits light. The light emitting device according to claim 1, comprising a reflective filler.   3. The light emitting device according to claim 1, wherein the second phosphor particles are unevenly distributed in the sealing resin so as to increase the density of the first light emitting element side and the second light emitting element side.   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 fluorescence. The light-emitting device according to claim 1, comprising body particles and second green phosphor particles.   5. 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 1.   The base has a first wiring and a second wiring separated from each other, the first light emitting element is connected to the first wiring, and the second light emitting element is connected to the second wiring. Item 6. The light emitting device according to any one of Items 1 to 5.   The plurality of first light emitting elements are included, the plurality of first light emitting elements are connected in series by the first wiring, the plurality of second light emitting elements are included, and the plurality of second light emitting elements are connected by the second wiring. The light-emitting device according to claim 6 connected in series. A plurality of the first light emitting elements, a plurality of the second light emitting elements,
The first light emitting elements and the second light emitting elements are arranged in rows and columns,
The light emitting device according to claim 1, wherein the first light emitting elements and the second light emitting elements are alternately arranged in each row and column.   Each of the first light emitting element and the second light emitting element has a substantially rectangular shape, and each of the first light emitting element and the second light emitting element is arranged in a diagonal direction of the substantially rectangular shape, and the first light emitting element The light-emitting device according to claim 7 or 8, wherein a row in which elements are arranged in a diagonal direction and a row in which the second light-emitting elements are arranged in a diagonal direction are alternately arranged.   The light emitting device according to claim 1, wherein a refractive index of the light transmitting body is higher than a refraction of the sealing resin.   The light emitting device according to any one of claims 1 to 10, wherein a thickness of the phosphor layer is 0.2 to 1.5 times a thickness of the light transmitting body.   The light emitting device according to claim 1, wherein the phosphor layer has a thickness of 35 to 200 μm.   The light emitting device according to claim 1, wherein the second wavelength conversion member is surrounded by a frame.

Images