JP2023128619A - Light-emitting device - Google Patents

Abstract

To provide a light-emitting device having wide directivity.SOLUTION: A light-emitting device comprises a first resin 13 that covers the whole top surface of a substrate 10 and that is arranged to come into contact with at least one side surface of a light-emitting element 11, and a second resin 14 that is arranged on the first resin 13. The first resin 13 is arranged lower than a top surface of the light-emitting element 11, on an outer peripheral surface closest to the light-emitting element 11, and arranged higher than the top surface of the light-emitting element 11, on the side facing the outer peripheral surface across the light-emitting element 11.SELECTED DRAWING: Figure 3

Description

The present invention relates to a light emitting device including a light emitting element.

Various light emitting devices are known that use light emitting diodes (LEDs) that emit visible light to improve directivity. In the light-emitting device described in Patent Document 1, a light-emitting element is mounted in a cavity, sealed with a sealing resin, and then a part of the cavity wall is removed to widen the radiation angle and create a light-emitting device with wide directivity. It is disclosed to manufacture.

JP 2017-123367 (Figure 1)

In the light emitting device described in Patent Document 1, light emitted laterally from the light emitting element is reflected in a direction returning to the light emitting element by a cavity wall that is perpendicular to the substrate surface. The light that reaches the light emitting element may be absorbed by the light emitting element and is not emitted from the light emitting device, resulting in a decrease in luminous efficiency. Furthermore, the path of light from the light emitting element to the light emitting device is approximately twice that of the side surface without a cavity wall. Once the light is taken into the sealing resin, it is diffused within the sealing resin, so it is not easy to control light with a long path.

Furthermore, in the light emitting device described in Patent Document 1, after the light emitting device with the cavity structure is manufactured, processing such as cutting is performed to remove at least one of the cavity walls, which increases the number of man-hours. In addition, when cutting, there are variations in the dimensions of materials such as circuit boards and the mounting precision of light emitting elements, making it difficult to control the cutting position, making the product shape, especially the resin shape, unstable, and the required directivity. It is not easy to obtain.

The present invention solves such problems, and aims to provide a light-emitting device that has a wide directivity by arranging a resin that controls light so as to surround a light-emitting element.

A light emitting device according to the present invention includes an insulating substrate having a rectangular planar shape, a plurality of wirings arranged on the substrate, and a light emitting device arranged on the surface of the plurality of wirings and electrically connected to at least one of the plurality of wirings. a light emitting element having a rectangular planar shape, a first resin disposed to cover the upper surface of the substrate and in contact with a side surface of the light emitting element, and a second resin disposed on the first resin. However, the first resin is disposed lower than the top surface of the light emitting element on the outer peripheral surface closest to the light emitting element, and higher than the upper surface of the light emitting element on the side opposite to the outer peripheral surface with the light emitting element in between.

Furthermore, in the light emitting device according to the present invention, the first resin has a concave curved shape from the top of the side surface of the light emitting element toward the outer peripheral surface, and the first resin has a concave curved shape from the top of the side surface of the light emitting element toward the opposite side. , preferably has a convex curved shape.

Furthermore, in the light emitting device according to the present invention, the light emitting element is arranged near the corner of the substrate, and the first resin has a concave curved shape from the top of the side surface of the light emitting element toward the side perpendicular to the outer peripheral surface. It is preferable to have.

Furthermore, in the light emitting device according to the present invention, it is preferable that the first resin has a top portion extending over the entire length at the top of the outer circumferential surface provided on the opposite side thereof.

Further, in the light emitting device according to the present invention, two light emitting elements are provided, and the opposing sides are the sides located between one light emitting element and the other light emitting element, and the opposite sides are the sides between one light emitting element and the other light emitting element. The elements are arranged near opposing corners on the substrate, and the first resin is formed between the top of the outer peripheral part and the top of the outer peripheral surface provided on the side opposite to the outer peripheral surface. It is preferable to have a continuous top portion near the center of the surface.

Furthermore, in the light emitting device according to the present invention, it is preferable that the light emitting element emits infrared rays.

The light-emitting device according to the present invention is arranged on the surface of a flat substrate, and the shape of the dam resin in contact with the light-emitting element is made higher than the light-emitting element at the center of the product and lower than the light-emitting element at the outer periphery of the product. The directivity of the emitted light can be controlled.

FIG. 1 is a perspective view of a light emitting device according to a first embodiment. 2 is a plan view of the light emitting device shown in FIG. 1. FIG. 3 is a sectional view taken along line AA shown in FIG. 2. FIG. 3 is a sectional view taken along line BB shown in FIG. 2. FIG. 2 is a flowchart showing a method for manufacturing the light emitting device shown in FIG. 1. FIG. FIG. 3 is a perspective view of a light emitting device according to a second embodiment. 7 is a plan view of the light emitting device shown in FIG. 6. FIG. 8 is a sectional view taken along line CC shown in FIG. 7. FIG. It is a top view of the board|substrate of the light emitting device based on a 1st modification. It is a top view of the board|substrate of the light emitting device based on a 2nd modification.

Hereinafter, a light emitting device according to the present invention will be described with reference to the drawings. However, it should be noted that the technical scope of the present invention is not limited to these embodiments, but extends to the invention described in the claims and equivalents thereof.

(Configuration and functions of the light emitting device according to the first embodiment)
1 is a perspective view of the light emitting device according to the first embodiment, FIG. 2 is a plan view of the light emitting device shown in FIG. 1, and FIG. 3 is a sectional view taken along line AA shown in FIG. 2. 4 is a sectional view taken along the line BB shown in FIG. 2.

The light emitting device 1 includes a substrate 10, a first wiring pattern 101, a second wiring pattern 102, a first electrode 103, a second electrode 104, a first light emitting element 11, a wire 12, and a first resin 13. and a second resin 14. The light emitting device 1 emits light in response to voltage being applied between the first electrode 103 and the second electrode 104.

The substrate 10 is a printed circuit board having a rectangular planar shape and made of an insulating resin such as glass epoxy, BT resin, or polyimide. The substrate 10 may be a ceramic substrate with high thermal conductivity such as ceramic. A first wiring pattern 101 and a second wiring pattern 102 are arranged spaced apart from each other on the front surface of the substrate 10, and a first electrode 103 and a second electrode 104 are spaced apart from each other on the back surface of the substrate 10. be done.

The substrate 10 has a first side 105, a second side 106, a third side 107, and a fourth side 10 on the outer periphery.
8. The first side 105 and the third side 107 are arranged to face each other, and the second side 106 and the fourth side 108 are arranged to face each other. Further, the first side 105 and the third side 107 are arranged perpendicularly to the second side 106 and the fourth side 108, respectively. When the substrate 10 has a rectangular planar shape, the first side 105 and the third side 107 are the long sides, and the second side 106 and the fourth side 108 are the short sides.

The first wiring pattern 101, the second wiring pattern 102, the first electrode 103, and the second electrode 104 have a rectangular planar shape and are made of a conductive material such as copper. The first wiring pattern 101 is arranged close to the second side 106 and is electrically connected to the first electrode 103 by conductive connecting means such as a via provided with a through hole in the substrate 10 . At this time, the distance between the first wiring pattern 101 and the first side 105 is shorter than the distance between the first wiring pattern 101 and the third side 107. The second wiring pattern is disposed close to the fourth side 108 and is electrically connected to the second electrode 104 by conductive connection means such as a via provided with a through hole in the substrate 10 . The distance between the second wiring pattern 102 and the first side 105 is shorter than the distance between the second wiring pattern 102 and the third side 107.

The light emitting element 11 is a rectangular planar LED die, and emits ultraviolet light, visible light, and infrared light. One example is infrared light with a wavelength of 850 nm. The light emitting element 11 has an anode on the front surface and a cathode on the back surface. The cathode of the light emitting element 11 is placed on the surface of the first wiring pattern 101 and electrically connected to the first wiring pattern 101 with a conductive adhesive or the like. The anode of the light emitting element 11 is electrically connected to the second wiring pattern 102 via the wire 12. Note that when the light-emitting element 11 has an anode and a cathode on the lower surface of the light-emitting element 11, such as a flip-chip type, the anode of the light-emitting element 11 is connected to a second electrode using a conductive adhesive or the like without using the wire 12. It may be electrically connected to the wiring pattern 102.

The wire 12 is made of a conductive metal material such as gold, silver, copper, or aluminum. The wire 12 is connected to the anode of the light emitting element 11 and the second wiring pattern 102 . The wire 12 is covered with a second resin 14 from the anode of the light emitting element 11 to the vicinity of the midpoint of the wire 12, and the second wiring pattern 102 is covered with the first resin 13 from the vicinity of the midpoint of the wire 12. The light emitting element 11 emits light when a current is supplied between the anode and the cathode from the first electrode 103 and the second electrode 104. Note that when the light emitting element 11 has an anode and a cathode on the lower surface like a flip chip, the wire 12 may be omitted.

The first resin 13 is a white resin made of silicone resin containing titanium oxide, barium sulfide, etc., and has reflective and light-shielding properties, and is arranged so as to cover the entire surface of the substrate 10. The first resin 13 contacts all four side surfaces of the light emitting element 11 and controls light directed to the sides of the light emitting element 11. When the light emitting element 11 emits infrared light, the light emitting element 11 has a color close to black, so by covering the four sides of the light emitting element 11 with the first resin 13, the emitted light is absorbed by the light emitting element 11. This can be suppressed. Furthermore, since the first resin 13 covers the upper surface of the substrate 10, it is possible to reflect the light emitted from the light emitting element 11 and directed toward the upper surface of the substrate 10 without transmitting it, thereby increasing the light output efficiency of the light emitting device 1. can be increased. Furthermore, the substrate 10 can be made of an inexpensive material that does not have reflective or light-shielding properties.

The second resin 14 is a silicone resin containing a filler and the like, and is placed on the top surface of the first resin 13, and has a flat surface. The second resin 14 diffuses the light emitted from the light emitting element 11 within the second resin 14 and causes the light to be emitted to the outside of the second resin 14 . Note that it is preferable that the first resin 13 and the second resin 14 are made of resins having the same components. Delamination between the first resin 13 and the second resin 14 can be suppressed.

The light emitting element 11 is arranged near one corner of the rectangular substrate 10. Light emitting element 1
1 is close to the first side 105 and the second side 106 and is spaced apart from the third side 107 and the fourth side 108. The light emitted from the light emitting element 11 and directed toward the first side 105 and the second side 106 has a shorter distance to pass through the second resin 14 between the light emitting element 11 and the first side 105 and the second side 106. Since the light scattered within the second resin 14 can be reduced, the efficiency of light emitted toward the sides of the light emitting device 1 is increased.

The first resin 13 is arranged so as to be in contact with the side surface of the light emitting element 11 . The first resin 13 has a shape that is asymmetrical with respect to the light emitting element 11 when the light emitting element 11 is viewed in cross section in a direction parallel to the second side 106 and the fourth side 108. Between the light emitting element 11 and the first side 105, the first resin 13 has a first recess 131 that is convex toward the substrate 10 at a position lower than the upper surface of the light emitting element 11. Between the light emitting element 11 and the third side 107, the first resin 13 has a second recess 132 that is convex toward the substrate 10 and a second recess 132 that is concave toward the substrate 10 at a position higher than the upper surface of the light emitting element 11. The first convex portion 133 has a continuous shape. The second concave portion 132 is arranged so as to be in contact with the light emitting element 11, and the first convex portion 133 is separated from the light emitting device 11 with an inflection point at the intersection of the second concave portion 132 and the first convex portion 133. It is arranged toward the three sides 107. The first convex portion 133 has a top portion 134 having a shape extending over the entire length of the third side 107 above the third side 107 . The top portion 134 is disposed close to the surface of the second resin 14 and has a cross-sectional shape in which the position farthest from the substrate 10 is the apex.

The first recess 131 is in contact with at least one side surface of the light emitting element 11 and is disposed at a position lower than the top surface of the light emitting element 11 . The first recess 131 is surrounded by the light emitting element 11 and the first side 105 and the second side 106, which are two outer edges of the substrate 10 close to the light emitting element 11. When viewed in cross-section, the surface of the first recess 131 has its top at the position in contact with the light emitting element 11, and is curved gently into a concave top surface without being higher than the top, and the first side 105 of the substrate 10 and The shape is directed toward the second side 106.

The first recess 131 blocks the emitted light L1 in a direction parallel (horizontal) to the upper surface of the substrate 10 from the side surface of the light emitting element 11 toward the first side 105 and the second side 106 of the substrate 10, and the emitted light L2 Emit it as is. Further, the first recess 131 reflects the light scattered within the second resin 14. Thereby, the light output of the light emitting device 1 can be adjusted and the directivity of light can be expanded.

The top of the first recess 131 is preferably 1/2 or more of the height of the light emitting element 11 in order to contact the side surface of the light emitting element 11 and shielding the emitted light L1. Furthermore, the top of the first recess 131 is preferably below the top surface of the light emitting element 11 so as not to obstruct the emitted light L2. At this time, the emitted light L2 may be light directed upward from parallel (horizontal) to the upper surface of the substrate 10, or may be light directed downward. Further, the surface shape of the first recess 131 may be a flat shape that is not curved. Further, it is preferable that the lowest point of the first recess 131 be located above the first side 105 because the reflected light will not return to the second resin 14 .

The second recess 132 is disposed at a position opposite to the first recess 131 with respect to the center of the light emitting element 11 and between the third side 107 and the light emitting element 11 . When viewed in cross section, the surface of the second recessed portion 132 has its lowest point at the position where it contacts the light emitting element 11, and curves gently toward the third side 107 in a concave shape at the top without becoming lower than the lowest point. It becomes the shape. The second recess 132 is not arranged on the upper surface of the light emitting element 11. The second recess 132 blocks the emitted light L3 from the side surface of the light emitting element 11 toward the third side 107, and reflects the emitted light L4 from the upper surface of the light emitting element 11, thereby emitting light at a position where the light output peaks. It can be positioned closer to the first side 105 and the second side 106 than directly above the element 14, and the directivity of the light of the light emitting device 1 can be expanded. Note that the surface shape of the second recess 132 may be a flat shape that is not curved.

The first convex portion 133 has a shape on the third side 107 of the first resin 13, and the surface of the first convex portion 133 has a gently curved shape with a convex top surface when viewed in cross section. coincides with the surface of the second resin 14 , and the bottom portion is connected to the top of the second recess 132 . Since the first convex portion 133 has a gently curved shape with a convex top surface, the light L5 emitted from the top surface of the light emitting element 11 can be gradually emitted without being concentrated. Note that the top portion 134 of the first convex portion 133 is adjusted by the amount of suppression of the emitted light L5. For example, when it is desired to reduce the emitted light L5, the top portion 134 of the first convex portion 133 may be higher than the surface of the second resin 14, and when it is desired to increase the emitted light L5, the top portion 134 of the first convex portion 133 may be higher than the surface of the second resin 14. may be lower than the surface of the second resin 14.

FIG. 5 is a flowchart showing a method for manufacturing the light emitting device 1.

First, in a substrate preparation step, a substrate 10 is prepared in which a first wiring pattern 101 and a second wiring pattern 102 are arranged on the front surface, and a first electrode 103 and a second electrode 104 are arranged on the back surface (S101). Next, in a light emitting element arrangement step, the light emitting element 11 is arranged on the surface of the first wiring pattern 101 so that the light emitting element 11 does not protrude from the first wiring pattern 101, and the light emitting element 11 is connected by a conductive connecting material. The lower surface and the surface of the first wiring pattern 101 are electrically connected (S102). Next, in a wire bonding step, the upper surface of the light emitting element 11 and the second wiring pattern 102 are electrically connected by the wire 12 (S103).

Next, in the first resin placement step, the first resin 13 is placed so as to be in contact with at least one side surface of the light emitting element 11 while along the third side 107 of the substrate 10 . At this time, the viscosity of the first resin 13 is adjusted so as to maintain a shape in which the top 134 is above the third side 107, and the top 134 of the first resin 13 is higher than the top surface of the light emitting element 11. Become. The first resin 13 spreads to cover the surface of the substrate 10 due to the weight of the first resin 13 and the surface tension between the first resin 13 and the surface of the substrate 10 . Furthermore, the entire surface of the side surface of the light emitting element 11 that comes into contact with the first resin 13 when placed is covered with the first resin 13. Thereafter, due to the surface tension between the first resin 13 and the light emitting element 11, it spreads to the side surface of the light emitting element 11 that is perpendicular to the side surface in contact with the first resin 13, and further faces the side surface in contact with the first resin 13. It spreads to the side surface of the light emitting element 11. Since the amount of the first resin 13 gradually decreases as the distance from the discharged position increases, the height of the first resin 13 gradually increases from the side of the substrate 10 that is distant from the light emitting element 11 toward the first side 105. becomes lower. After the first resin 13 has spread over the surface of the substrate 10, the first resin 13 may be cured by a method such as heating (S104).

Next, in the second resin arrangement step, the second resin 14 covers the upper surface of the first resin 13 and is arranged with a flat surface. After the second resin 14 is placed, the second resin 14 is cured by a method such as heating (S105), thereby manufacturing the light emitting device 1.

(Operations and effects of the light emitting device according to the first embodiment)
In the light emitting device 1, the light emitting element 11 is located close to the first side 105 and the second side 106, which are asymmetrical with respect to the outer periphery of the substrate 10, is spaced apart from the third side 107, and is located further away from the fourth side 108. will be placed in Since the light emitting device 1 can have the peak position of the emitted light near the corner of the substrate 10 instead of the center of the light emitting device 1, the directivity of the emitted light can be easily expanded.

Further, in the light emitting device 1, the light emitting element 11 is arranged close to the first side 105 and the second side 106. The amount of the second resin 14 is reduced between the light emitting element 11 and the first side 105 and the second side 106. Since the possibility of the light emitted from the light emitting element 11 being scattered within the second resin 14 can be reduced, the amount of light directed to the outside of the second resin 14 on the side of the light emitting element 11 can be increased, and the orientation of the light emitting device 1 can be increased. It becomes easier to expand your sexuality.

Further, in the light emitting device 1, the light emitting element 11 is arranged apart from the third side 107 and the fourth side 108. There is a large space between the light emitting element 11 and the third side 107 and the fourth side 108, so that the thickness of the first resin 13 can be adjusted, and the reflection and light blocking performance of the first resin 13 can be easily ensured. This makes it easier to adjust the directivity of the light in step 1.

Furthermore, in the light emitting device 1, the first resin 13 is in contact with four side surfaces of the light emitting element 11, and blocks light directed to the sides of the light emitting element 11 without forming the substrate 10 into a cavity structure. Since the first resin 13 contains metal, it serves as a heat dissipation path for transmitting part of the heat generated from the light emitting element 11 to the substrate 10 and the like. Further, the manufacturing cost is lower than that of a construction method in which the substrate 10 is formed into a cavity structure and then the walls of the cavity are removed. Note that the first resin 13 may be arranged so as to cover 1/2 or more of the side surface of the light emitting element 11 on the side surface facing the adjacent outer periphery of the substrate 10 of the light emitting element 11 . The light output of the light emitted from the light emitting element 11 on the side of the light emitting device 1 can be adjusted by the area of the first resin 13 that covers the side surface of the light emitting element 11 .

In the light emitting device 1, the first resin 13 is composed of a first recess 131, a second recess 132, and a first protrusion 133, and has a gently curved surface with several inflection points. shape, and is arranged so as to cover the entire upper surface of the substrate 10. The first resin 13 can reflect the emitted light of the light emitting element 11 toward the surface of the substrate 10, reduce the light transmitted through the substrate 10, and increase the emitted light from the second resin 14, thereby increasing the luminous efficiency. can do.

Furthermore, in the light emitting device 1, the first recess 131 suppresses the emitted light L1, and allows the emitted light L2 to be emitted as is. Moreover, since the first recess 131 reflects the light scattered within the second resin 14 of the emitted light L2, the amount of emitted light L2 can be increased. The light emitting device 1 can widen the directivity of light by the emitted light L2.

Furthermore, in the light emitting device 1, the second recess 132 blocks the emitted light L3 and reflects the emitted light L4. The second recess 132 increases the emitted light L4 directed toward the outer edge of the substrate 10 than directly above the light emitting element 11, and makes the peak position of the emitted light of the light emitting device 1 more direct toward the outer edge of the substrate 10 than directly above the light emitting element 11. to the side.

Further, in the light emitting device 1, the first convex portion 133 reflects the emitted light L4 in the vicinity of the second concave portion 132 from directly above the light emitting element 11 in a direction approaching the first convex portion 133, and This suppresses the occurrence of so-called hot spots, where light is concentrated.

(Configuration and functions of light emitting device according to second embodiment)
6 is a perspective view of the light emitting device according to the second embodiment, FIG. 7 is a plan view of the light emitting device shown in FIG. 6, and FIG. 8 is a sectional view taken along line CC shown in FIG. It is.

The light emitting device 2 includes a light emitting element 21a and another light emitting element 21b rotated by 180 degrees around the midpoint of the center line 107a of the substrate 20. Note that the light emitting device 2 has a shape in which two light emitting devices 1 are joined so that the third sides 107 of the two light emitting devices 1 are aligned. The configurations and functions of the components of the light emitting device 2 are the same as those of the components of the light emitting device 1 with the same reference numerals, so detailed explanations will be omitted here. For convenience, the reference numerals related to one light emitting element of the light emitting device 2 will be described below with a suffix "a", and the reference numerals related to the other light emitting element will be described below with a suffix "b". .

The light emitting device 2 includes a substrate 20, a first wiring pattern 201, a second wiring pattern 202, a third wiring pattern 203, a fourth wiring pattern 204, a first electrode 205, a second electrode 206, and a second wiring pattern 202. The third electrode 207, the fourth electrode 208, the first light emitting element 21a, and the second light emitting element 2
1b, a wire 22, a first resin 23, and a second resin 24. The light emitting device 2 emits light in response to voltage being applied between the first electrode 205 to the fourth electrode 208.

The substrate 20 has the same configuration and function as the substrate 10, and will not be described here. The substrate 20 has, for example, a square planar shape, and is surrounded by a first side 20a, a second side 20b, a third side 20c, and a fourth side 20d arranged counterclockwise. The first side 20a and the third side 20c are orthogonal to the second side 20b and the fourth side 20d, respectively.

The first wiring pattern 201 to the fourth wiring pattern 204 and the first electrode 205 to the fourth electrode 208 have the same configuration as the first wiring pattern 101 to the second wiring pattern 102 and the first electrode 103 to the second electrode 104. This function is omitted here. The first wiring pattern 201 to the fourth wiring pattern 204 are electrically connected to the first electrode 205 to the fourth electrode 208 arranged on the back surface of the substrate 20, respectively. The first wiring pattern 201 connects the first side 20a and the second side 20b of the board 20, the second wiring pattern 202 connects the first side 20a and the fourth side 20d of the board 20, and the third wiring pattern 203 connects the board 20 to the first side 20a and the second side 20b. The third side 20c and the fourth side 20d of the substrate 20 and the fourth wiring pattern 204 are arranged close to the second side 20b and the third side 20c of the substrate 20.

The first light emitting element 21a and the second light emitting element 21b have the same configuration and function as the light emitting element 11, and will not be described here. The cathode of the first light emitting element 21a is connected to the surface of the first wiring pattern 201, and the anode of the first light emitting element 21a is electrically connected to the second wiring pattern 202. The second light emitting element 21b is electrically connected to the third wiring pattern 203 and the fourth wiring pattern 204 at positions that are point symmetrical about the center of the first light emitting element 21a and the light emitting device 2.

The wire 22 is made of a conductive metal material such as gold, silver, copper, or aluminum. The wire 22 is connected to the anode of the first light emitting element 21a and the second wiring pattern 202. The wire 22 is covered with the second resin 24 from the anode of the first light emitting element 21a to the vicinity of the midpoint of the wire 22, and the second wiring pattern 202 is covered with the first resin 23 from the vicinity of the midpoint of the wire 22. Note that when the first light emitting element 21a has an anode and a cathode on the lower surface like a flip chip, the wire 22 may be omitted. The wire 22 is configured in the second light emitting element 21b using the same connection method as in the first light emitting element 21a.

The first resin 23 is a white resin having reflective and light-shielding properties made of silicone resin containing titanium oxide, barium sulfide, etc., and is disposed so as to cover the entire surface of the substrate 20. The first resin 23 is arranged so as to be in contact with all side surfaces of the first light emitting element 21a and the second light emitting element 21b, and controls light directed to the sides of the first light emitting element 21a and the second light emitting element 21b. Furthermore, when the first light emitting element 21a and the second light emitting element 21b emit infrared light, the first light emitting element 21a and the second light emitting element 21b have a color close to black. By covering all side surfaces of the light emitting element 21b with the first resin 23, absorption of emitted light can be suppressed. Note that since the upper surface of the substrate 20 is covered with the first resin 23, the light emitted from the light emitting device 2 is not emitted from the side and lower surfaces of the substrate 20, so that the directivity of the light can be easily controlled. Furthermore, the substrate 20 can be made of an inexpensive material that does not have reflective or light blocking properties.

The second resin 24 is a silicone resin containing filler and the like, and is disposed on the upper surface of the first resin 23, and has a flat surface. The second resin 24 diffuses the light emitted from the first light emitting element 21a and the second light emitting element 21b within the second resin 24, and emits the light to the outside. Note that it is preferable that the first resin 23 and the second resin 24 are made of resins having the same components. Delamination between the first resin 23 and the second resin 24 can be suppressed.

The first light emitting element 21a is arranged near one corner of the substrate 20 and close to the first side 20a and the second side 20b. The second light emitting element 21b is disposed near another corner of the substrate 20, facing the first light emitting element 21a, and close to the third side 20c and the fourth side 20d. The light emitted from the first light emitting element 21a and the second light emitting element 21b and directed toward the first side 20a to the fourth side 20d has a short distance from each light emitting element to each side of the substrate 20, and the light emitted from the second resin 21b Since the light scattered inside can be reduced, the light output efficiency of the light emitting device 2 is increased.

The first resin 23 is in contact with the side surface of the first light emitting element 21a, and when the first light emitting element 21a is viewed in cross section in a direction parallel to the second side 20b and the fourth side 20d, the first resin 23 has the first light emitting element 21a as the center. It has an asymmetrical shape. The first resin 23 has a first recess 131a that is convex toward the substrate 20 between the first light emitting element 21a and the first side 20a. The first recess 131a is lower than the top surface of the first light emitting element 21a. The first resin 23 has a second recess 132a that is convex toward the substrate 20 near the first light emitting element 21a between the first light emitting element 21a and the third side 20c, and has a second recess 132a that is convex toward the substrate 20. In the vicinity of 20c, a first convex portion 133a is provided on the opposite side of the substrate 20. The second concave portion 132a and the first convex portion 133a are higher than the upper surface of the second light emitting element 21a. Note that the first resin 23 has a similar shape (suffix b) on the second light emitting element 21b side where the first light emitting element 21a is point symmetrical with respect to the center of the light emitting device 2, and also on the second light emitting element 21b side. , has the same effect as the first light emitting element 21a side. Further, the first resin 23 has a top portion 134a disposed over the entire length above the center line 107a of the substrate 20, where the first convex portion 133a and the first convex portion 133b are in contact.

The configurations and functions of the components of the first recess 131a, second recess 132a, first protrusion 133a, first recess 131b, second recess 132b, and first protrusion 133b of the light emitting device 2 are given the same reference numerals. Since the configurations and functions of the components of the first recess 131, second recess 132, and first protrusion 133 of the light emitting device 1 are the same, detailed explanation will be omitted here. Note that the positions of the top portions 134a of the first convex portion 133a and the first convex portion 133b are adjusted by the amount of suppression of the emitted light L5a and the emitted light L5b. For example, when it is desired to reduce the emitted light L5a and the emitted light L5b, the top portion 134a may be higher than the surface of the second resin 24, and when it is desired to increase the emitted light L5a and the emitted light L5b, the top portion 134a may be higher than the surface of the second resin 24. It may be lower than the surface of the resin 24. Since the top portion 134a has a curved shape with a convex upper surface, the output light L5a and the output light L5b can be easily suppressed.

(Operations and effects of the light emitting device according to the second embodiment)
In the light emitting device 2, the substrate 20 has a rectangular planar shape, and the first light emitting element 21a and the second light emitting element 21b are arranged at opposite corners of the rectangular planar shape. In other words, since the light emitting device 2 is arranged at the farthest position on the rectangular planar substrate, the directivity of light from the light emitting device 2 can be easily expanded. The first resin 23 controls the emitted light L1a to L4a, and provides light directivity having a peak in the direction of the first side 20a from directly above the first light emitting element 21a. The second light emitting element 21b controls the emitted light L1b to L4b by the first resin 23, and obtains light directivity having a peak in the direction of the first side 20c from directly above the second light emitting element 21b. The light emitting device 2 combines the emitted light L5a of the first light emitting element 21a and the emitted light L5b of the second light emitting element 21b, so that the top of the first resin 23 between the first light emitting element 21a and the second light emitting element 21b is combined. A decrease in the output of light above the portion 134a can be suppressed. Thereby, the light emitting device 2 has a wide directivity in which the peak of the emitted light is located closer to the outer periphery of the substrate 20 than the first light emitting element 21a and the second light emitting element 21b. In addition, the light emitting device 2 emits a flat light whose oval shape, such as an ellipse, is rotated 360 degrees in the horizontal direction at the center of the light emitting device 2 when viewed in cross section so that the peaks of the two emitted lights do not become dark. Directivity is obtained.

(Configuration and function of light emitting device according to modification)
FIG. 9 is a plan view of a substrate of a light emitting device according to a first modification, and FIG. 10 is a plan view of a substrate of a light emitting device according to a second modification.

In FIG. 9, the light emitting device 3 according to the first modification has a first wiring pattern 301 instead of the first wiring pattern 101 of the light emitting device 1. The configurations and functions of the components of the light emitting device 3 are the same as those of the components of the light emitting device 1 with the same reference numerals, so detailed explanations will be omitted here.

The first wiring pattern 301 has a rectangular portion 302 that matches the shape of the first wiring pattern 101 and a convex portion 303 . The convex portion 303 has a shape that protrudes from near the center of one outer periphery of the rectangular portion 302 toward the third side 107, and the tip of the convex portion 303 extends so as to be close to the third side 107. .

The first resin 13 is arranged along the third side 107 so as to be in contact with the convex portion 303 . The first resin 13 in contact with the surface of the convex portion 303 spreads to the rectangular portion 302 along the surface of the convex portion 303 . On the other hand, when the first resin 13 in contact with the surface of the substrate 10 goes toward the light emitting element 11 , it may be blocked by the side surface of the first wiring pattern 301 and may not reach the light emitting element 11 . The convex portion 303 functions as a resin flow path for the first resin 13 that allows the first resin 13 to reach the light emitting element 11 reliably and easily covers the surface of the rectangular portion 302 and the side surface of the light emitting element 11.

Note that the protrusion 303 may be a resist made of an insulating resin such as epoxy. When the light emitting device 3 requires complicated wiring, the protrusion 303 is insulative and will not cause an electrical short circuit even if it comes into contact with other wiring, making the design easier.

In FIG. 10, the light emitting device 4 according to the second modification has a first wiring pattern 401 instead of the first wiring pattern 301. The configurations and functions of the components of the light emitting device 4 are the same as those of the components of the light emitting device 3, which are denoted by the same reference numerals, so detailed explanations will be omitted here.

The first wiring pattern 401 has a rectangular section 402 that matches the shape of the rectangular section 302 , a convex section 403 that matches the shape of the convex section 303 , and a second rectangular section 404 . One end of the convex portion 403 is in contact with the rectangular portion 402 , and the opposite end is in contact with the second rectangular portion 404 . The second rectangular portion 404 has a rectangular planar shape and is arranged above the third side 107 to cover from the second side 106 to the fourth side 108.

The first resin 13 is arranged so as to cover the entire upper surface of the second rectangular portion 404 and partially cover the convex portion 403 . The first resin 13 in contact with the surfaces of the convex portion 403 and the second rectangular portion 404 spreads from the surface of the convex portion 403 to the surface of the rectangular portion 402 . The second rectangular portion 404 can increase the amount of the first resin 13 disposed on the surface of the first wiring pattern 401, and since the amount of the first resin 13 directed toward the rectangular portion 402 increases, it covers the sides of the light emitting element 11. It becomes easier. The convex portion 403 and the second rectangular portion 404 function as a resin flow path for the first resin 13.

Note that the convex portion 403 and the second rectangular portion 404 may be a resist made of an insulating resin such as epoxy. When the light emitting device 4 requires complicated wiring, the convex portion 403 and the second rectangular portion 404 are insulative and will not cause an electrical short circuit even if they come into contact with other wiring, making the design easier. Further, since the second rectangular portion 404 is disposed above the third side 107 and the side surfaces are exposed, the possibility of short circuit can be reduced if the second rectangular portion 404 is made of an insulating material.

1 Light-emitting device 10 Substrate 101 First wiring pattern 102 Second wiring pattern 103 First electrode 104 Second electrode 11 Light-emitting element 12 Wire 13 First resin 14 Second resin

Claims (6)

an insulating substrate having a rectangular planar shape;
a plurality of wirings arranged on the substrate;
a light emitting element having a rectangular planar shape disposed on the surface of the plurality of wirings and electrically connected to at least one of the plurality of wirings;
a first resin disposed to cover an upper surface of the substrate and to be in contact with a side surface of the light emitting element;
a second resin disposed on the first resin;
The first resin is disposed lower than the top surface of the light emitting element on the outer peripheral surface closest to the light emitting element, and higher than the upper surface of the light emitting element on the side opposite to the outer peripheral surface with the light emitting element in between. A light emitting device characterized by: The first resin has a concave curved shape from the top of the side surface of the light emitting element toward the outer peripheral surface, and has a convex curved shape from the top of the side surface of the light emitting element toward the opposing side. The light emitting device according to claim 1, characterized in that it has: The light emitting element is arranged near a corner of the substrate,
3. The light emitting device according to claim 2, wherein the first resin has a concave curved shape from the top of the side surface of the light emitting element toward a side perpendicular to the outer peripheral surface. The light emitting device according to claim 1, wherein the first resin has a top portion extending over the entire length at the top of the outer circumferential surface provided on the opposing sides. Providing two of the light emitting elements,
The opposing side is a side located between one light emitting element and another light emitting element,
The one light emitting element and the other light emitting element are respectively arranged near opposing corners on the substrate,
The first resin may have a continuous top portion near the center of a surface formed between the top of the outer peripheral portion and the top of an outer peripheral surface provided on a side opposite to the outer peripheral surface. The light emitting device according to any one of claims 1 to 3, characterized in that: The light emitting device according to claim 1, wherein the light emitting element emits infrared rays.

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