JP6845996B2 - Light emitting device and lighting device - Google Patents

Description

Embodiments of the present invention relate to a light emitting device and a lighting device.

There is a light emitting device provided with a plurality of types of light emitting elements having different colors of emitted light. Such a light emitting device can irradiate light of all colors (full color) by controlling the lighting and extinguishing of the light emitting element for each color of light.
In order to irradiate full-color light, at least three types of light emitting elements (a light emitting element that emits green light, a light emitting element that emits blue light, and a light emitting element that emits red light) are required. Further, in order to control the average color rendering index Ra, for example, a light emitting element that emits yellow light or a light emitting element that emits orange light is further required.

Here, in order to control the lighting and extinguishing of the light emitting element for each color of light, as many independent wiring patterns as the number of types of the light emitting element are required on the substrate. Therefore, the wiring pattern provided on the substrate may be complicated, or it may be difficult to mount a plurality of light emitting elements at high density.

Further, when mounting a plurality of light emitting elements, it is conceivable to use a laminated substrate.
However, as the number of layers of the laminated substrate increases, the thermal resistance increases, which causes a new problem that the heat dissipation of the mounted light emitting element deteriorates. Since some types of light emitting elements have poor temperature characteristics, if the heat dissipation of the light emitting element is poor, the temperature of the light emitting element rises, which may cause color unevenness and brightness unevenness. Further, if the heat dissipation of the light emitting element is poor, the power applied to the light emitting element cannot be increased, so that there is a possibility that high output cannot be achieved.
Therefore, it has been desired to develop a technique capable of improving heat dissipation by providing a plurality of types of light emitting elements.

Japanese Unexamined Patent Publication No. 2014-082236

An object to be solved by the present invention is to provide a light emitting device and a lighting device, which are provided with a plurality of types of light emitting elements and can improve heat dissipation.

The light emitting device according to the embodiment includes a laminated substrate in which a first layer and a second layer are laminated. The laminated substrate is provided with at least two pattern wirings on either side of the first layer between the first layer and the second layer or on the side opposite to the first layer of the second layer, and at least one of them has at least two pattern wirings. One pattern wiring is provided. Further, the laminated substrate penetrates the first layer in the thickness direction and penetrates the first conductive via electrically connected to the pattern wiring arranged between the first layers and the first layer and the second layer in the thickness direction. It includes a second conductive via that is electrically connected to a pattern wiring arranged on the side opposite to the first layer of the second layer. Further, the light emitting device includes a plurality of types of light emitting elements which are dispersedly arranged on the side opposite to the first layer of the first layer and are electrically connected for each pattern wiring.

According to the embodiment of the present invention, it is possible to provide a light emitting device and a lighting device which are provided with a plurality of types of light emitting elements and can improve heat dissipation.

It is a schematic plan view for exemplifying the light emitting device 1 which concerns on this embodiment. FIG. 5 is a cross-sectional view taken along the line AA in FIG. (A) is a schematic cross-sectional view for exemplifying a face-up type light emitting diode 120a and its wiring form. (B) is a schematic cross-sectional view for exemplifying a flip-chip type light emitting diode 120b and its wiring form. (C) is a schematic cross-sectional view for exemplifying the upper and lower electrode type light emitting diodes 120c and the wiring form thereof. It is a schematic cross-sectional view for exemplifying the lighting apparatus 100 which concerns on this embodiment.

According to the light emitting device of the invention according to the embodiment, it is possible to provide a plurality of types of light emitting elements and improve heat dissipation.

Further, among the plurality of types of light emitting elements, the plurality of light emitting elements that emit light of the same color are divided into a plurality of groups, and the plurality of light emitting elements that emit the same color of light included in each group are described above. Wiring and mounting pads are connected in series to each other on the first surface, and pattern wiring is used between each group on a second surface opposite to the first surface of the laminated substrate or between layers of the laminated substrate. It can be made to be connected in series with each other.
In this way, even when a plurality of types of light emitting elements are distributed and arranged at high density, it becomes easy to connect a plurality of light emitting elements in series for each color of light.

Further, the plurality of types of light emitting elements include a first light emitting element that emits green light, a second light emitting element that emits blue light, a third light emitting element that emits red light, and a phosphor. It can be a fourth light emitting element that emits yellow or orange light.
By doing so, it is possible to irradiate full-color light. It is also possible to control the average color rendering index Ra.

Further, at least a part of the plurality of the third light emitting elements and the plurality of the fourth light emitting elements can be provided outside the region where the plurality of the second light emitting elements are provided. ..
By doing so, it becomes easy to dissipate heat from the third light emitting element having poor temperature characteristics, so that it is possible to suppress the occurrence of color unevenness and brightness unevenness. Further, the distance between the fourth light emitting element having a phosphor and the second light emitting element that emits light having a short wavelength can be increased. Therefore, it is possible to prevent light having a short wavelength emitted from the second light emitting element from entering the phosphor of the fourth light emitting element and causing unintended fluorescence. Therefore, the color reproducibility can be improved.

The invention according to the embodiment is a lighting device including the above-mentioned light emitting device; and a housing in which the light emitting device is housed;
According to this lighting device, it is possible to provide a plurality of types of light emitting elements and improve heat dissipation.

Hereinafter, embodiments will be illustrated with reference to the drawings. In each drawing, similar components are designated by the same reference numerals and detailed description thereof will be omitted as appropriate.

(Light emitting device)
FIG. 1 is a schematic plan view for exemplifying the light emitting device 1 according to the present embodiment.
In addition, in order to avoid complication, in FIG. 1, the sealing portion 40, the wiring portion 12, and the like are omitted.
FIG. 2 is a cross-sectional view taken along the line AA in FIG.
As shown in FIGS. 1 and 2, the light emitting device 1 is provided with a substrate 10, a light emitting portion 20, a frame portion 30, and a sealing portion 40.

The substrate 10 has layers 11a to 11d, wiring portions 12a to 12g, and input terminals 12ha to 12hg. The substrate 10 is a laminated substrate.
The layers 11a to 11d have a plate shape. The layer 11b is provided on one surface side of the layer 11a. The layer 11c is provided on the side of the layer 11b opposite to the side on which the layer 11a is provided. The layer 11d is provided on the side of the layer 11c opposite to the side on which the layer 11b is provided. That is, the layers 11a to 11d are laminated. The layers 11a to 11d are preferably formed using a material having a high thermal conductivity. The material having high thermal conductivity can be, for example, an inorganic material such as ceramics (for example, aluminum oxide or aluminum nitride).

The wiring portion 12a has a mounting pad 12a1, a conductive via 12a2, a pattern wiring 12a3, a pattern wiring 12a4, and a conductive via 12a5.
The mounting pad 12a1 is provided on the surface of the layer 11d opposite to the layer 11c side (corresponding to an example of the first surface). The mounting pad 12a1 is provided inside the frame portion 30. One mounting pad 12a1 is provided for one light emitting element 20y.
The conductive via 12a2 penetrates the layer 11d in the thickness direction. The conductive via 12a2 electrically connects the predetermined mounting pad 12a1 and the pattern wiring 12a3. Details regarding the connection between the predetermined mounting pad 12a1 and the pattern wiring 12a3 will be described later.
The conductive vias 12a5 penetrate the layers 11c to 11a in the thickness direction. The conductive via 12a5 electrically connects the pattern wiring 12a3 and the pattern wiring 12a4.
The pattern wiring 12a3 is provided between the layer 11c and the layer 11d.
The pattern wiring 12a4 is provided on the surface of the layer 11a opposite to the layer 11b side (corresponding to an example of the second surface). The pattern wiring 12a4 is electrically connected to the corresponding input terminal 12ha.

The wiring portion 12b has a mounting pad 12b1, a conductive via 12b2, a pattern wiring 12b3, a pattern wiring 12b4, and a conductive via 12b5.
The mounting pad 12b1 is provided on the surface of the layer 11d opposite to the layer 11c side. The mounting pad 12b1 is provided inside the frame portion 30. One mounting pad 12b1 is provided for one light emitting element 20o.
The conductive via 12b2 penetrates the layer 11d in the thickness direction. The conductive via 12b2 electrically connects the predetermined mounting pad 12b1 and the pattern wiring 12b3. Details regarding the connection between the predetermined mounting pad 12b1 and the pattern wiring 12b3 will be described later.
The conductive vias 12b5 penetrate the layers 11c to 11a in the thickness direction. The conductive via 12b5 electrically connects the pattern wiring 12b3 and the pattern wiring 12b4.
The pattern wiring 12b3 is provided between the layer 11c and the layer 11d.
The pattern wiring 12b4 is provided on the surface of the layer 11a opposite to the layer 11b side. The pattern wiring 12b4 is electrically connected to the corresponding input terminal 12hb.

The wiring portion 12c has a mounting pad 12c1, a conductive via 12c2, a pattern wiring 12c3, a pattern wiring 12c4, and a conductive via 12c5.
The mounting pad 12c1 is provided on the surface of the layer 11d opposite to the layer 11c side. The mounting pad 12c1 is provided inside the frame portion 30. One mounting pad 12c1 is provided for one light emitting element 20r.
The conductive via 12c2 penetrates the layers 11c and 11d in the thickness direction. The conductive via 12c2 electrically connects the predetermined mounting pad 12c1 and the pattern wiring 12c3. Details regarding the connection between the predetermined mounting pad 12c1 and the pattern wiring 12c3 will be described later.
The conductive via 12c5 penetrates the layers 11b and 11a in the thickness direction. The conductive via 12c5 electrically connects the pattern wiring 12c3 and the pattern wiring 12c4.
The pattern wiring 12c3 is provided between the layers 11b and 11c.
The pattern wiring 12c4 is provided on the surface of the layer 11a opposite to the layer 11b side. The pattern wiring 12c4 is electrically connected to the corresponding input terminal 12hc.

The wiring portion 12d has a mounting pad 12d1, a conductive via 12d2, a pattern wiring 12d3, a pattern wiring 12d4, and a conductive via 12d5.
The mounting pad 12d1 is provided on the surface of the layer 11d opposite to the layer 11c side. The mounting pad 12d1 is provided inside the frame portion 30. One mounting pad 12d1 is provided for one light emitting element 20c.
The conductive vias 12d2 penetrate the layers 11c and 11d in the thickness direction. The conductive via 12d2 electrically connects the predetermined mounting pad 12d1 and the pattern wiring 12d3. Details regarding the connection between the predetermined mounting pad 12d1 and the pattern wiring 12d3 will be described later.
The conductive via 12d5 penetrates the layers 11b and 11a in the thickness direction. The conductive via 12d5 electrically connects the pattern wiring 12d3 and the pattern wiring 12d4.
The pattern wiring 12d3 is provided between the layers 11b and 11c.
The pattern wiring 12d4 is provided on the surface of the layer 11a opposite to the layer 11b side. The pattern wiring 12d4 is electrically connected to the corresponding input terminal 12hd.

The wiring portion 12e has a mounting pad 12e1, a conductive via 12e2, a pattern wiring 12e3, a pattern wiring 12e4, and a conductive via 12e5.
The mounting pad 12e1 is provided on the surface of the layer 11d opposite to the layer 11c side. The mounting pad 12e1 is provided inside the frame portion 30. One mounting pad 12e1 is provided for one light emitting element 20b1.
The conductive vias 12e2 penetrate the layers 11b to 11d in the thickness direction. The conductive via 12e2 electrically connects the predetermined mounting pad 12e1 and the pattern wiring 12e3. Details regarding the connection between the predetermined mounting pad 12e1 and the pattern wiring 12e3 will be described later.
The conductive via 12e5 penetrates the layer 11a in the thickness direction. The conductive via 12e5 electrically connects the pattern wiring 12e3 and the pattern wiring 12e4.
The pattern wiring 12e3 is provided between the layers 11a and 11b.
The pattern wiring 12e4 is provided on the surface of the layer 11a opposite to the layer 11b side. The pattern wiring 12e4 is electrically connected to the corresponding input terminal 12he.

The wiring portion 12f includes a mounting pad 12f1, a conductive via 12f2, a pattern wiring 12f3, a pattern wiring 12f4, and a conductive via 12f5.
The mounting pad 12f1 is provided on the surface of the layer 11d opposite to the layer 11c side. The mounting pad 12f1 is provided inside the frame portion 30. One mounting pad 12f1 is provided for one light emitting element 20g.
The conductive vias 12f2 penetrate the layers 11b to 11d in the thickness direction. The conductive via 12f2 electrically connects the predetermined mounting pad 12f1 and the pattern wiring 12f3. Details regarding the connection between the predetermined mounting pad 12f1 and the pattern wiring 12f3 will be described later.
The conductive via 12f5 penetrates the layer 11a in the thickness direction. The conductive via 12f5 electrically connects the pattern wiring 12f3 and the pattern wiring 12f4.
The pattern wiring 12f3 is provided between the layers 11a and 11b.
The pattern wiring 12f4 is provided on the surface of the layer 11a opposite to the layer 11b side. The pattern wiring 12f4 is electrically connected to the corresponding input terminal 12hf.

The wiring portion 12g has a mounting pad 12g1, a conductive via 12g2, and a pattern wiring 12g3.
The mounting pad 12g1 is provided on the surface of the layer 11d opposite to the layer 11c side. The mounting pad 12g1 is provided inside the frame portion 30. One mounting pad 12g1 is provided for one light emitting element 20b2.
The conductive vias 12g2 penetrate the layers 11a to 11d in the thickness direction. The conductive via 12g2 electrically connects the predetermined mounting pad 12g1 and the pattern wiring 12g3. Details regarding the connection between the predetermined mounting pad 12g1 and the pattern wiring 12g3 will be described later.
The pattern wiring 12g3 is provided on the surface of the layer 11a opposite to the layer 11b side. The pattern wiring 12g3 is electrically connected to the corresponding input terminal 12hg.

Here, the plurality of light emitting elements are electrically connected for each color of light so that the lighting and extinguishing of the light emitting element can be controlled for each color of light. Further, in order to make the values of the currents flowing through each light emitting element equal, a plurality of light emitting elements are connected in series for each color of light.
However, as shown in FIG. 1, the light emitting elements 20y to 20b2 are dispersedly arranged on one surface of the layer 11d. Therefore, it may be difficult to connect a plurality of light emitting elements in series for each color of light on one surface of the layer 11d, or it may be difficult to mount the light emitting elements 20y to 20b2 at high density.

Therefore, in the light emitting device 1 according to the present embodiment, the pattern wirings 12a3 to 12g3 and the conductive vias 12a2 to facilitate the serially connected light emitting elements 20y to 20b2 arranged in a distributed manner for each color of light. 12g2 is provided.
For example, a plurality of mounting pads 12a1 arranged according to a plurality of distributed light emitting elements 20y are divided into a plurality of groups depending on whether or not they can be connected in series by wiring 21, and a plurality of light emitting elements included in each group. The 20y is connected in series with the wiring 21 and the mounting pad 12a1, and is electrically connected in series with the pattern wiring 12a3 and the conductive via 12a2 between the groups.
The plurality of mounting pads 12b1 arranged according to the plurality of distributed light emitting elements 20o are divided into a plurality of groups depending on whether or not they can be connected in series by the wiring 21, and the plurality of light emitting elements 20o included in each group are The wiring 21 and the mounting pad 12b1 are connected in series to each other, and the pattern wiring 12b3 and the conductive via 12b2 are electrically connected in series between the groups.
The plurality of mounting pads 12c1 arranged according to the plurality of distributed light emitting elements 20r are divided into a plurality of groups depending on whether or not they can be connected in series by the wiring 21, and the plurality of light emitting elements 20r included in each group are The wiring 21 and the mounting pad 12c1 are connected in series to each other, and the pattern wiring 12c3 and the conductive via 12c2 are electrically connected in series between the groups.

The plurality of mounting pads 12d1 arranged according to the plurality of distributed light emitting elements 20c are divided into a plurality of groups depending on whether or not they can be connected in series by the wiring 21, and the plurality of light emitting elements 20c included in each group are The wiring 21 and the mounting pad 12d1 are connected in series to each other, and the pattern wiring 12d3 and the conductive via 12d2 are electrically connected in series between the groups.
The plurality of mounting pads 12e1 arranged according to the plurality of distributed light emitting elements 20b1 are divided into a plurality of groups depending on whether or not they can be connected in series by the wiring 21, and the plurality of light emitting elements 20b1 included in each group are The wiring 21 and the mounting pad 12e1 are connected in series to each other, and the pattern wiring 12e3 and the conductive via 12e2 are electrically connected in series between the groups.
The plurality of mounting pads 12f1 arranged according to the plurality of distributed light emitting elements 20g are divided into a plurality of groups depending on whether or not they can be connected in series by the wiring 21, and the plurality of light emitting elements 20g included in each group are The wiring 21 and the mounting pad 12e1 are connected in series to each other, and the pattern wiring 12f3 and the conductive via 12f2 are electrically connected in series between the groups.
The plurality of mounting pads 12g1 arranged according to the plurality of distributed light emitting elements 20b2 are divided into a plurality of groups depending on whether or not they can be connected in series by the wiring 21, and the plurality of light emitting elements 20b2 included in each group are The wiring 21 and the mounting pad 12e1 are connected in series to each other, and the pattern wiring 12g3 and the conductive via 12g2 are electrically connected in series between the groups.

In this way, even when a plurality of types of light emitting elements are distributed and arranged at high density, it becomes easy to connect a plurality of light emitting elements in series for each color of light.
Further, in the present embodiment, any two or more of the pattern wirings 12a3 to 12f3 are provided at the same position (same layer). For example, the pattern wiring 12a3 and the pattern wiring 12b3, the pattern wiring 12c3 and the pattern wiring 12d3, and the pattern wiring 12e3 and the pattern wiring 12f3 are provided at the same position (same layer). Therefore, the number of layers excluding the layer provided with the light emitting element can be half or less of the number of types of the light emitting element. For example, in the case of the example shown in FIG. 2, three layers 11b to 11d may be provided for the seven types of light emitting elements 20y to 20b2. In this case, if the number of layers can be reduced, the thermal resistance can be reduced, so that the heat generated in the light emitting elements 20y to 20b2 can be easily dissipated.
That is, according to the present embodiment, it is possible to provide a light emitting device provided with a plurality of types of light emitting elements and capable of improving heat dissipation.

Here, the light emitting element 20r that emits red light may have a decrease in luminous efficiency or a shift in emission color as the temperature rises. If the luminous efficiency is lowered or the emission color is shifted, color unevenness or brightness unevenness may occur. Further, if the heat dissipation of the light emitting element is poor, the power applied to the light emitting element cannot be increased, so that there is a possibility that high output cannot be achieved.

According to this embodiment, since the thermal resistance can be reduced, it is possible to suppress the occurrence of color unevenness and brightness unevenness. In addition, high output can be achieved.
The position of the wiring portion and the number of pattern wirings provided between the same layers can be appropriately changed according to the arrangement of the light emitting elements described later, the number of types of the light emitting elements, and the like.

Further, in the present embodiment, each of the pattern wirings 12a3 to 12g3 is provided between one layer and is not provided dispersed between a plurality of layers. Therefore, the wiring portions 12a to 12g can be simplified, and the manufacturing cost can be reduced.

The input terminals 12ha to 12hg are provided on the surface of the layer 11a opposite to the layer 11b side.
A power supply (not shown), a control device, or the like provided outside the light emitting device 1 is electrically connected to the input terminals 12ha to 12hg.
Therefore, the light emitting device 1 can irradiate full-color light by controlling lighting and extinguishing for each type of light emitting element.

The materials of the wiring portions 12a to 12g and the input terminals 12ha to 12hg are not particularly limited as long as they are conductive materials. The materials of the wiring portions 12a to 12g and the input terminals 12ha to 12hg can be, for example, metals such as silver, copper, gold, and tungsten.
When the materials of the layers 11a to 11d are ceramics, the substrate 10 can be formed by, for example, the LTCC (Low Temperature Co-fired Ceramics) method. For example, the substrate 10 can be formed by simultaneously firing layers 11a to 11d, wiring portions 12a to 12g, and input terminals 12ha to 12hg at a temperature of 900 ° C. or lower.

Further, a heat spreader (not shown) may be provided on the surface of the substrate 10 opposite to the side on which the light emitting portion 20 is provided. A heat spreader (not shown) can be connected to the substrate 10 via heat conductive grease, solder, or the like. If a heat spreader (not shown) is provided, the heat generated in the light emitting unit 20 can be conducted and dispersed. Therefore, the electric power applied to the light emitting unit 20 can be increased, so that the amount of light emitted from the light emitting device 1 can be increased. Further, since it becomes easy to secure the heat conduction path, it is possible to suppress an increase in the temperature of the sealing portion 40 and, by extension, the temperature of the light emitting portion 20.

The light emitting unit 20 has light emitting elements 20y, 20o, 20r, 20c, 20b1, 20g, and 20b2.
The light emitting element 20y emits yellow light, for example. The light emitting element 20y emits light having a peak wavelength of 570 nm or more and 590 nm or less, for example. The light emitting element 20y may include, for example, a light emitting diode that emits blue light and a phosphor that is provided on the light emitting surface of the light emitting diode and emits yellow fluorescence.
The light emitting element 20o emits, for example, orange light. The light emitting element 20o emits light having a peak wavelength of more than 590 nm and 620 nm or less, for example. The light emitting element 20o may include, for example, a light emitting diode that emits blue light and a phosphor that is provided on the light emitting surface of the light emitting diode and emits amber fluorescence.
The light emitting element 20r emits red light, for example. The light emitting element 20r can be, for example, a light emitting diode that emits light having a peak wavelength of 610 nm or more and 660 nm or less.

The light emitting element 20c emits cyan light, for example. The light emitting element 20c can be, for example, a light emitting diode that emits light having a peak wavelength of 500 nm or more and 505 nm or less.
The light emitting element 20b1 can be, for example, a light emitting diode that emits blue light having a peak wavelength of about 475 nm.
The light emitting element 20g emits green light, for example. The light emitting element 20g can be, for example, a light emitting diode that emits light having a peak wavelength of more than 505 nm and 540 nm or less.
The light emitting element 20b2 can be, for example, a light emitting diode that emits blue light having a peak wavelength of about 450 nm.

As an example, the case where seven types of light emitting elements 20y to 20b2 are provided has been illustrated, but at least three types of light emitting elements (a light emitting element that emits green light, a light emitting element that emits blue light, and a red light are used. A light emitting element that emits light) may be provided.
However, if four or more types of light emitting elements are provided as in the example, the average color rendering index Ra can also be controlled.

The light emitting elements 20y to 20b2 are mounted on the mounting pads 12a1 to 12g1 by using a COB (Chip on Board) method. The light emitting elements 20y to 20b2 are bonded onto the mounting pads 12a1 to 12g1 via a silver paste, silver nanopaste, or the like. The light emitting elements 20y to 20b2 are upper and lower electrode type light emitting diodes.

Here, the type of the light emitting diode includes a face-up type, a flip-chip type, and an upper and lower electrode type depending on the position of the electrode.
Further, when a plurality of light emitting diodes are electrically connected, they are connected in series in order to make the values of the currents flowing through the light emitting diodes equal.

FIG. 3A is a schematic cross-sectional view for exemplifying the face-up type light emitting diode 120a and its wiring form.
As shown in FIG. 3A, in the case of the face-up type light emitting diode 120a, the light emitting diode 120a is mounted on the surface of the substrate 110. Then, the positive electrode and the negative electrode provided on the upper surface of the light emitting diode 120a and the mounting pad 112a provided in the vicinity of the light emitting diode 120a are electrically connected via the wiring 21.

In this case, a space for providing the mounting pad 112a and a space for connecting the wiring 21 are required between the light emitting diodes 120a. Therefore, it is necessary to increase the distance between the light emitting diodes 120a.

As described above, in the case of the face-up type light emitting diode 120a, a space for providing the light emitting diode 120a, a space for providing the mounting pad 112a, and a wiring 21 for connecting the space for providing the light emitting diode 120a and the wiring 21 on one surface of the substrate 110. Space is needed. As a result, space efficiency is reduced, which makes high-density mounting difficult. In addition, wiring work for the positive electrode and the negative electrode is required, which may lead to a decrease in productivity and an increase in manufacturing cost.

FIG. 3B is a schematic cross-sectional view for exemplifying the flip-chip type light emitting diode 120b and its wiring form.
As shown in FIG. 3B, in the case of the flip-chip type light emitting diode 120b, the light emitting diode 120b is mounted on the mounting pad 112b provided on the surface of the substrate 110.
If the flip-chip type light emitting diode 120b is used, space efficiency can be improved and high-density mounting becomes possible.

However, in the case of the light emitting device 1 that irradiates full-color light, at least three types of light emitting elements are required. Further, as illustrated in FIG. 1, a plurality of types of light emitting elements are dispersedly arranged. Then, it is necessary to connect a plurality of distributed light emitting elements in series for each type of light emitting element (for each color of light). Therefore, the shape of the wiring pattern provided on one surface of the substrate 110 becomes complicated, and as a result, it becomes necessary to increase the distance between the light emitting diodes 120b. This becomes more remarkable as the number of types of light emitting elements increases.
Therefore, in the case of the light emitting device 1 that irradiates full-color light, if the flip-chip type light emitting diode 120b is used, high-density mounting may be difficult or the light emitting device 1 may be enlarged.

FIG. 3C is a schematic cross-sectional view for exemplifying the upper and lower electrode type light emitting diodes 120c and the wiring form thereof.
As shown in FIG. 3C, in the case of the upper and lower electrode type light emitting diodes 120c, the light emitting diodes 120c are mounted on the mounting pads 112c provided on the surface of the substrate 110. If the upper and lower electrode type light emitting diodes 120c are used, space efficiency can be improved and, by extension, high-density mounting becomes possible as compared with the face-up type light emitting diodes 120a.

Further, one electrode of the light emitting diode 120c is connected to the mounting pad 112c via the wiring 21. Therefore, the degree of freedom regarding the position and shape of the mounting pad 112c is increased. In the case of the light emitting device 1 that irradiates full-color light, since a plurality of types of light emitting elements are dispersedly arranged, it is better to use the upper and lower electrode type light emitting diodes 120c than to use the flip chip type light emitting diodes 120b. On the contrary, space efficiency can be improved, which in turn enables high-density mounting.
Therefore, the light emitting elements 20y to 20b2 are upper and lower electrode type light emitting diodes.

In the light emitting elements 20y to 20b2, which are upper and lower electrode type light emitting diodes, the electrode (lower electrode) on the substrate 10 side is a conductive bond such as lead-free solder (SAC: SnAgCu, etc.) or gold-tin (AuSn) alloy paste. It is electrically connected to the mounting pads 12a1 to 12g1 via the material. The electrodes (upper electrodes) of the light emitting elements 20y to 20b2 on the opposite side to the substrate 10 side are electrically connected to the mounting pads 12a1 to 12g1 via the wiring 21. The wiring 21 can be connected by using, for example, a wire bonding method.

Next, the arrangement of the light emitting elements 20y to 20b2 will be described.
As described above, the light emitting element 20r that emits red light may have a decrease in luminous efficiency or a shift in emission color as the temperature rises. If the luminous efficiency is lowered or the emission color is shifted, color unevenness or brightness unevenness may occur. Therefore, it is preferable to determine the arrangement position of the light emitting element 20r in consideration of heat dissipation. In this case, the peripheral region 13 of the region where the light emitting elements 20y to 20b2 are provided (for example, the region inside the frame portion 30) is more likely to dissipate heat than the central region 14. Therefore, the light emitting element 20r is preferably provided in the peripheral region 13 of the region where the light emitting elements 20y to 20b2 are provided.

When a plurality of light emitting elements 20r are collected in the peripheral region 13, it seems that ring-shaped light is irradiated on the irradiation surface when only red light is irradiated from the light emitting device 1. However, red light has a long wavelength and a wide half-value width, so that it is easy to diffuse. Therefore, even if a plurality of light emitting elements 20r are collected in the peripheral region 13, it is possible to suppress the irradiation of the ring-shaped red light on the irradiation surface.

Further, the light emitting elements 20c, 20b1 and 20b2 that emit blue or cyan light have a short wavelength and a narrow half-value width, so that they are difficult to diffuse. Therefore, if the light emitting elements 20c, 20b1 and 20b2 are collected in the peripheral region 13, when only blue or cyan light is irradiated from the light emitting device 1, ring-shaped light may be irradiated on the irradiation surface. Therefore, it is preferable that the light emitting elements 20c, 20b1 and 20b2 are provided in the central region 14 of the region where the light emitting elements 20y to 20b2 are provided.

The light emitting elements 20c, 20b1 and 20b2 are less likely to have a decrease in luminous efficiency or a shift in emission color as the temperature rises. Therefore, even if the light emitting elements 20c, 20b1 and 20b2 are provided in the central region 14 where heat dissipation is difficult, there is little possibility that color unevenness and brightness unevenness occur.

Further, considering that white light is emitted from the light emitting device 1, the total number of the light emitting elements 20c, 20b1 and 20b2 is about 1/4 of the total number of the light emitting elements 20y, 20o, 20r and 20g. Therefore, if a small number of light emitting elements 20c, 20b1 and 20b2 are provided in the central region 14 having a small area, it is possible to prevent the distance between the light emitting elements from becoming excessively long or excessively short. be able to.

Further, the light emitting element 20y that emits yellow light and the light emitting element 20o that emits orange light have a phosphor. Therefore, when the light emitting elements 20y and 20o are adjacent to the light emitting elements 20c, 20b1 and 20b2 that emit light having a short wavelength, the light having a short wavelength emitted from the light emitting elements 20c, 20b1 and 20b2 is incident on the phosphor. As a result, unintended fluorescence may occur. Unintended fluorescence can reduce color reproducibility. Therefore, it is preferable that the light emitting elements 20y and 20o are not adjacent to the light emitting elements 20c, 20b1 and 20b2 as much as possible.

For example, it is preferable that the light emitting elements 20y and 20o are provided in the peripheral region 13 as much as possible. Even if red light having a long wavelength is incident on the phosphors of the light emitting elements 20y and 20o, fluorescence does not occur. Therefore, even if the light emitting element 20r that emits red light and the light emitting elements 20y and 20o are provided in the peripheral region 13, there is no possibility that unintended fluorescence will occur.

That is, at least a part of the plurality of light emitting elements 20y, the plurality of light emitting elements 20o, and the plurality of light emitting elements 20r is outside the region where the plurality of light emitting elements 20c, the plurality of light emitting elements 20b1, and the plurality of light emitting elements 20b2 are provided. It is provided in.

Further, since the light emitting element 20r does not have a phosphor, there is no possibility that unintended fluorescence will occur even if the light emitting element 20r and the light emitting elements 20c, 20b1 and 20b2 are adjacent to each other. Therefore, it is more preferable to provide the light emitting element 20r between the light emitting elements 20y and 20o and the light emitting elements 20c, 20b1 and 20b2. By doing so, the distance between the light emitting elements 20y and 20o and the light emitting elements 20c, 20b1 and 20b2 can be increased, so that unintended fluorescence can be suppressed in the light emitting elements 20y and 20o. ..

In this case, the number of light emitting elements 20y and 20o adjacent to the light emitting elements 20c, 20b1 and 20b2 is preferably smaller than the number of light emitting elements 20r adjacent to the light emitting elements 20c, 20b1 and 20b2.

Further, since the light emitting element 20g emits light having a wavelength longer than that of the light emitting elements 20c, 20b1 and 20b2, the light emitting element 20g may be provided between the light emitting elements 20y and 20o and the light emitting elements 20c, 20b1 and 20b2. it can. In this case, it is more preferable to provide the light emitting element 20g between the light emitting element 20r and the light emitting elements 20c, 20b1 and 20b2. By doing so, the distance between the light emitting elements 20y and 20o and the light emitting elements 20c, 20b1 and 20b2 can be further increased, so that unintended fluorescence is further suppressed in the light emitting elements 20y and 20o. be able to.

Further, when the area of the upper surface 40a of the sealing portion 40 (the light emitting area of the light emitting device 1) is S1 and the total area of the light emitting elements 20y to 20b2 is S2, S2 / S1 is set to be less than 0.2. Since the distance between the light emitting elements 20y to 20b2 becomes long, it becomes easy to suppress the occurrence of unintended fluorescence in the light emitting elements 20y and 20o.
However, if S2 / S1 is set to less than 0.2, the distance between the light emitting elements 20y to 20b2 becomes too long, and a larger light emitting area is required to obtain the same amount of light.

On the other hand, when S2 / S1 exceeds 0.3, the distance between the light emitting elements 20y to 20b2 becomes too short, and unintended fluorescence is likely to occur in the light emitting elements 20y and 20o.
Therefore, it is preferable that S2 / S1 is 0.2 or more and 0.3 or less.

The frame portion 30 has a frame shape. The frame portion 30 is provided on the surface of the substrate 10 on which the light emitting elements 20y to 20b2 are provided. The frame portion 30 is provided so as to surround the light emitting elements 20y to 20b2. The frame portion 30 can be formed of, for example, a resin such as PBT (polybutylene terephthalate) or PC (polycarbonate), ceramics, or the like.

Further, when the material of the frame portion 30 is a resin, particles made of titanium oxide or the like can be mixed to improve the reflectance with respect to the light emitted from the light emitting elements 20y to 20b2. The particles are not limited to titanium oxide particles, and particles made of a material having a high reflectance to the light emitted from the light emitting elements 20y to 20b2 may be mixed. Further, the frame portion 30 can also be formed of, for example, a white resin. That is, the frame portion 30 can have both the function of defining the region where the sealing portion 40 is formed and the function of the reflector. The shape of the frame portion 30 is not limited to the illustrated one, and can be changed as appropriate.
Further, the frame portion 30 is not always necessary and can be omitted. When the frame portion 30 is not provided, the shape of the sealing portion 40 can be, for example, a dome shape.

The sealing portion 40 is provided inside the frame portion 30. When the upper surface 40a of the sealing portion 40 is a flat surface, the height of the sealing portion 40 is preferably lower than the height of the frame portion 30. By doing so, it is possible to prevent the resin from overflowing to the outside of the frame portion 30 when the resin described later is supplied. The sealing portion 40 is provided so as to cover the light emitting elements 20y to 20b2. When the upper surface 40a of the sealing portion 40 is a flat surface, the height dimension of the sealing portion 40 can be, for example, about 2 to 5 times the thickness dimension of the light emitting elements 20y to 20b2. The thickness dimension of the light emitting elements 20y to 20b2 can be about 0.1 mm.

Further, the upper surface 40a of the sealing portion 40 may be, for example, a dome-shaped curved surface or the like.

The sealing portion 40 is formed of a translucent material. The sealing portion 40 can be formed of, for example, a transparent resin such as a silicone-based resin. In this case, the sealing portion 40 is preferably formed of a methyl silicone resin. This is because the methyl silicone resin has heat resistance and flexibility. In this case, the hardness of the methyl silicone resin is preferably about Shore A20 to A40.
The sealing portion 40 can be formed, for example, by supplying a resin to the inside of the frame portion 30. The resin can be supplied by using, for example, a liquid quantitative discharge device such as a dispenser.

(Manufacturing method of light emitting device 1)
Next, an example will be given of the method for manufacturing the light emitting device 1.
First, the substrate 10 is created. The substrate 10 can be formed, for example, by using the LTCC method. For example, it can be formed by forming the above-mentioned mounting pads, conductive vias, wiring portions, input terminals, and the like on the layers 11a to 11d and simultaneously firing them at a temperature of 900 ° C. or lower.

Next, the light emitting elements 20y to 20b2 are mounted on the substrate 10. At this time, the arrangement of the light emitting elements 20y to 20b2 is set to be as described above. Since known techniques can be applied to the mounting of the light emitting elements 20y to 20b2, detailed description thereof will be omitted.
Next, the frame portion 30 is provided so as to surround the light emitting elements 20y to 20b2. In this case, the frame-shaped frame portion 30 may be adhered to the substrate 10, or the resin may be applied to the substrate 10 in a frame shape and cured.

Next, a translucent resin is supplied to the inside of the frame portion 30 to form the sealing portion 40.
The resin can be supplied by using, for example, a liquid quantitative discharge device such as a dispenser. At this time, the viscosity of the supplied resin is adjusted to control the shape of the upper surface 40a of the sealing portion 40. For example, by supplying a resin having a low viscosity, the upper surface 40a of the sealing portion 40 becomes a flat surface. For example, by supplying a resin having a high viscosity, the upper surface 40a of the sealing portion 40 has a dome-shaped curved surface. The viscosity of the resin to be supplied can be determined, for example, by conducting an experiment or a simulation in advance.

Next, if necessary, a heat spreader is provided on the surface of the substrate 10 opposite to the side on which the light emitting elements 20y to 20b2 are provided.
As described above, the light emitting device 1 can be manufactured.

(Lighting device)
Next, an example will be given of the lighting device 100 according to the present embodiment.
FIG. 4 is a schematic cross-sectional view for exemplifying the lighting device 100 according to the present embodiment.
The lighting device 100 illustrated in FIG. 4 is a floodlight installed in a building, a stadium, or the like. The lighting device 100 according to the present embodiment is not limited to the floodlight. The lighting device 100 may be any device capable of irradiating full-color light.
As shown in FIG. 4, the lighting device 100 is provided with an irradiation unit 110 and a light source unit 120.

The irradiation unit 110 has a housing 111 and a reflector 112.
The housing 111 has a box shape. The housing 111 can be formed from, for example, an aluminum alloy. The end of the housing 111 opposite to the light source 120 side is open. This opening is closed by a translucent cover (not shown). A hole 111a is provided at the end of the housing 111 on the light source 120 side.

The reflector 112 is provided inside the housing 111. A flange 112a projecting outward is provided at the end of the reflector 112 on the side opposite to the light source portion 120 side. The flange 112a is fixed to a mounting plate (not shown) provided on the inner wall of the housing 111.

The reflector 112 can be a tubular body with both ends open. The reflector 112 has a form in which the cross-sectional dimension gradually decreases toward the light source unit 120 side. The inner surface of the reflector 112 is a mirror surface. The end portion of the reflector 112 on the light source portion 120 side is provided inside the hole portion 111a. The end of the reflector 112 on the light source portion 120 side is provided at a position facing the light emitting device 1. A hemispherical lens or the like may be arranged on the light emitting side of the light emitting device 1. Further, the light emitting surface of the lens can be diffused, or a diffusing sheet can be attached. By performing a diffusion treatment or attaching a diffusion sheet, the light emitted from the light emitting elements 20y to 20b2 can be diffused, so that the occurrence of color unevenness can be further suppressed.

The light source unit 120 includes a light emitting device 1, a housing 121, a mounting unit 122, a heat radiating unit 123, packing 124, heat radiating fins 125, and a heat pipe 126.
The housing 121 has a box shape. The housing 121 can be formed of, for example, an aluminum alloy. A hole is provided at the end of the housing 121 on the irradiation portion 110 side. Inside the hole, a light emitting device 1 attached to the attachment portion 122 is provided. That is, the light emitting device 1 is housed in the housing 121.

The mounting portion 122 has a plate shape. The mounting portion 122 can be formed of, for example, an aluminum alloy or the like. The mounting portion 122 is mounted on the heat radiating portion 123 by using a fastening member such as a screw. A recess is provided on the end surface of the mounting portion 122 on the irradiation portion 110 side. A light emitting device 1 is attached to the inside of the recess.

The heat radiating unit 123 has a plate shape. The heat radiating portion 123 can be formed of, for example, an aluminum alloy or the like. The heat radiating portion 123 is attached to the inside of the housing 121 by using a fastening member such as a screw (not shown).
The packing 124 has an annular shape. The packing 124 is provided between the heat radiating portion 123 and the inner wall surface of the housing 121.

The heat radiation fin 125 has a thin plate shape. A plurality of heat radiation fins 125 are provided. The heat radiation fin 125 can be formed from, for example, an aluminum alloy. The heat radiating fin 125 is provided on the surface of the heat radiating portion 123 opposite to the side on which the mounting portion 122 is provided.

The heat pipe 126 is provided between the heat radiating portion 123 and the heat radiating fin 125. A plurality of heat pipes 126 may be provided.
In addition, a control device (not shown) that controls the light emitting device 1 can be provided. For example, the control device controls turning on and off for each of the light emitting elements 20y to 20b2. Further, the control device controls the electric power supplied for each of the light emitting elements 20y to 20b2, and controls the light emission output for each of the light emitting elements 20y to 20b2.

Although some embodiments of the present invention have been illustrated above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other embodiments, and various omissions, replacements, changes, etc. can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof. Moreover, each of the above-described embodiments can be implemented in combination with each other.

1 Light emitting device, 10 boards, 11a to 11d layers, 12a to 12g wiring part, 12a1 to 12g1 mounting pad, 12a2 to 12g2 conductive via, 12a3 to 12g3 pattern wiring, 20y to 20b2 light emitting element, 30 frame part, 40 sealing part , 100 lighting device, 110 irradiation unit, 111 housing, 120 light source unit

Claims (5)

The first layer and the second layer are laminated,
At least two pattern wirings provided on either side of the first layer between the first layer and the second layer or on the side opposite to the first layer of the second layer, and at least provided on the other side. One pattern wiring and
The first conductive via that penetrates the first layer in the thickness direction and is electrically connected to the pattern wiring arranged between the first layers, the first layer and the second layer penetrates in the thickness direction, and the first layer. A laminated substrate including two layers of patterned wiring disposed on the opposite side of the first layer and a second conductive via electrically connected;
With a plurality of types of light emitting elements dispersedly arranged on the opposite side of the first layer from the first layer and electrically connected to each pattern wiring;
A light emitting device equipped with. The third layer is laminated on the side of the second layer opposite to the side on which the first layer is laminated, and the second layer and the third layer are on the side opposite to the first layer of the second layer. The light emitting device according to claim 1, wherein a second layer is formed between the two layers. The light emitting device according to claim 1, wherein each of the plurality of light emitting elements irradiates light of a different color and includes three or more types of light emitting elements having different light emitting colors. The light emitting device according to claim 2, wherein each of the plurality of light emitting elements irradiates light of a different color and includes four or more types of light emitting elements having different light emitting colors. With the light emitting device according to any one of claims 1 to 4;
With the housing in which the light emitting device is housed;
Lighting device equipped with.

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