Light emitting device

Abstract

To provide a light emitting device capable of keeping a radiant intensity constant for a predetermined angle even in the case where a light emitting element is arranged to be shifted.SOLUTION: A light emitting device includes a substrate, a light emitting element arranged on the substrate, and a translucent sealing member to seal the light emitting element. The translucent sealing member comprises a base and an outgoing light adjustment section which are formed integrally. The light emitting element is sealed inside the base. The outgoing light adjustment section is arranged above the light emitting element. The outgoing light adjustment section includes a lens part at the uppermost part thereof, a first tapered part connected to the lens part, a second tapered part connected to the first tapered part, and a third tapered part connected to the second tapered part and the base. An angle (θ3) between the upper face of the base and the third tapered part is 75 degrees or more and less than 90 degrees.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a light emitting device. [Background technology]

[0002] Light emitting devices that emit infrared rays have been known for some time. For example, Patent Document 1 discloses a configuration in which a lens in a light emitting device that emits infrared rays is provided with a tapered portion to make it easier to remove the lens from a mold during lens molding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2017-069587 Summary of the Invention [Problem to be solved by the invention]

[0004] However, due to manufacturing constraints, the light-emitting elements placed within the light-emitting device may be positioned in a position different from the originally planned position, which may result in a change in the directional characteristics of the infrared rays emitted from the light-emitting device.

[0005] An object of the present invention is to provide a light emitting device that can maintain directional characteristics within a predetermined range even when light emitting elements are arranged with misalignment. [Means for solving the problem]

[0006] The light-emitting device of the present invention comprises a substrate, a light-emitting element arranged on the substrate, and a translucent sealing member that seals the light-emitting element, wherein the translucent sealing member is composed of an integrally formed base and an emission light adjustment portion, the light-emitting element is sealed inside the base, the emission light adjustment portion is arranged above the light-emitting element, and the emission light adjustment portion has a lens portion at the top, a first tapered portion connected to the lens portion, a second tapered portion connected to the first tapered portion, and a third tapered portion connected to the second tapered portion and the base, and the angle (θ3) formed between the top surface of the base and the third tapered portion is greater than or equal to 75 degrees and less than 90 degrees.

[0007] Furthermore, in the light emitting device according to the present invention, the angle (θ2) that the second tapered portion makes with respect to a plane parallel to the substrate is preferably equal to or greater than 30 degrees and less than 90 degrees.

[0008] Furthermore, in the light emitting device according to the present invention, the angle (θ1) that the first tapered portion makes with respect to a plane parallel to the substrate is preferably equal to or greater than 20 degrees and less than 90 degrees.

[0009] Furthermore, in the light emitting device according to the present invention, the first tapered portion, the second tapered portion, and the third tapered portion preferably have a conical shape.

[0010] Furthermore, in the light emitting device according to the present invention, it is preferable that the base portion has a rectangular parallelepiped shape and has side surfaces formed by dicing. [Effects of the Invention]

[0011] According to the present invention, even when the light emitting elements are arranged with misalignment, the directivity characteristics can be maintained within a predetermined range. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a perspective view of a light emitting device according to a first embodiment. [Figure 2] 1 is a top view of a light emitting device according to a first embodiment. [Figure 3]FIG. 2 is a cross-sectional view taken along line AA' shown in FIG. [Figure 4] 1(a) to 1(e) are diagrams illustrating a method for manufacturing the light emitting device according to the first embodiment. [Figure 5] FIG. 10 is a perspective view of a light emitting device according to a second embodiment. [Figure 6] FIG. 10 is a top view of a light emitting device according to a second embodiment. [Figure 7] FIG. 6 is a cross-sectional view taken along the line BB' shown in FIG. [Figure 8] 1 is a diagram showing a range of α degrees left and right and a range of β degrees left and right based on the center of the emitted light adjustment unit when the center of the light-emitting element is positioned directly below the emitted light adjustment unit or when it is positioned at a specified distance in the light-emitting device of embodiment 1. [Figure 9] This figure shows a range of α degrees left and right and a range of β degrees left and right based on the center of the emitted light adjustment unit when the center of the light-emitting element is placed directly below the emitted light adjustment unit or when it is placed at a specified distance in the light-emitting device of embodiment 2. [Figure 10] This figure shows a range of α degrees left and right and a range of β degrees left and right from directly above the light-emitting element when the center of the light-emitting element is positioned in the same position as in Figure 8(a) in a light-emitting device of a comparative example. [Figure 11] FIG. 2 is a diagram showing parameters of the light emitting devices according to the first and second embodiments. [Figure 12] (a) is a diagram showing the relationship between the third tapered portion and the radiation intensity ratio in the light-emitting device of embodiment 1, and (b) is a diagram showing the relationship between the third tapered portion and the radiation intensity ratio in the light-emitting device of embodiment 2. [Figure 13] (a) is a diagram showing the relationship between the second tapered portion and the radiation intensity ratio in the light-emitting device of embodiment 1, and (b) is a diagram showing the relationship between the second tapered portion and the radiation intensity ratio in the light-emitting device of embodiment 2. [Figure 14] 4 is a diagram showing the relationship between a first tapered portion and a radiation intensity ratio in the light emitting device according to the first embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] The light emitting device according to the present invention will be described below with reference to the drawings. However, it should be noted that the technical scope of the present invention is not limited to the embodiments, but extends to the inventions set forth in the claims and their equivalents.

[0014] (Embodiment 1) FIG. 1 is a perspective view of the light emitting device 1 according to the first embodiment, FIG. 2 is a top view of the light emitting device 1 according to the first embodiment, and FIG. 3 is a cross-sectional view taken along line A-A' in FIG. 1. In the following description, the X-axis direction, the Y-axis direction, and the Z-axis direction will be used as necessary. These directions are perpendicular to each other. The Y-axis direction corresponds to the optical axis direction at the center of the light emitting element 11.

[0015] The light emitting device 1 includes a substrate 10, a light emitting element 11, a light-transmitting sealing member 12, and the like.

[0016] The substrate 10 is a printed circuit board having a rectangular planar shape and made of insulating resin such as glass epoxy, BT resin, or polyimide. The substrate 10 has a first wiring pattern 101 and a second wiring pattern 102 on its surface. The first wiring pattern 101 and the second wiring pattern 102 are arranged spaced apart from each other. The substrate 10 has a first electrode and a second electrode (not shown) on its back surface. The first electrode and the second electrode are arranged spaced apart from each other.

[0017] The first wiring pattern 101, the second wiring pattern 102, the first electrode, and the second electrode are formed of a conductive material such as copper. The first wiring pattern 101 is electrically connected to the first electrode by a conductive connection means such as a via having a through hole in the substrate 10. The second wiring pattern 102 is electrically connected to the second electrode by a conductive connection means such as a via having a through hole in the substrate 10.

[0018] The light-emitting element 11 is an LED die having a rectangular planar shape and emits infrared light. The dominant wavelength of the infrared light emitted from the light-emitting element 11 is, for example, between 800 nm and 1000 nm. The light-emitting element 11 is disposed on a substrate 10. The light-emitting element 11 has an anode on its front surface and a cathode on its back surface. The cathode of the light-emitting element 11 is disposed on the front 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 a wire 103. That is, the light-emitting element 11 is die-bonded and wire-bonded to the substrate 10. Although the present embodiment has been described as the light-emitting element 11 emitting infrared light, the light emitted by the light-emitting element 11 may be ultraviolet light or visible light.

[0019] The wire 103 is made of a conductive metal material such as gold, silver, copper, or aluminum. The wire 103 is connected to the anode of the light-emitting element 11 and the second wiring pattern 102. The light-emitting element 11 emits light when a current is supplied between the anode and cathode from the first electrode and the second electrode.

[0020] The light-transmitting sealing member 12 is a sealing resin that seals the light-emitting element 11, the wire 103, etc., and transmits light emitted from the light-emitting element 11. The light-transmitting sealing member 12 is formed, for example, from a colorless transparent resin such as epoxy resin or silicone resin. The light-transmitting sealing member 12 has a base 13 and an emitted light adjustment portion 14. The base 13 and the emitted light adjustment portion 14 are integrally formed.

[0021] The base 13 is disposed on the upper surface of the substrate 10, and seals the light emitting element 11, the wires 103, etc. inside the base 13. The base 13 has a rectangular parallelepiped shape and has side surfaces formed by dicing.

[0022] The emitted light adjustment unit 14 adjusts the emitted light from the light emitting element 11 so as to maintain the directional characteristics of the emitted infrared light within a predetermined range even when the light emitting element 11 is misaligned. The emitted light adjustment unit 14 is disposed above the light emitting element 11 at a position where the light emitting element 11 fits inside it in a planar view. The emitted light adjustment unit 14 has a circular shape in a planar view. The emitted light adjustment unit 14 has a lens portion 15 at the top, a first tapered portion 16 connected to the lens portion 15, a second tapered portion 17 connected to the first tapered portion 16, and a third tapered portion 18 connected to the second tapered portion 17 and the base portion 13.

[0023] The lens portion 15 is disposed at a position where the light emitting element 11 fits inside in a plan view, and collects and emits light from the light emitting element 11. The lens portion 15 has a circular shape in a plan view. The first tapered portion 16 and the second tapered portion 17 have a conical shape, and collect and emit light from the light emitting element 11.

[0024] The third tapered portion 18 has a conical shape and condenses and emits light from the light emitting element 11. The third tapered portion 18 makes it easier to remove the emitted light adjustment portion 14 from the mold when forming the emitted light adjustment portion 14. Furthermore, the third tapered portion 18 circulates light reflected within the emitted light adjustment portion 14 and the base portion 13 even when the light emitting element 11 is misaligned.

[0025] If the angle θ1 is the angle that the first tapered portion 16 makes with respect to a plane P1, which is the surface of the light-emitting element 11 parallel to the substrate 10, the angle θ2 is the angle that the second tapered portion 17 makes with respect to the plane P1, and the angle θ3 is the angle that the top surface P2 of the base 13 makes with the third tapered portion 18, then the angle θ3 is preferably 75 degrees or more and less than 90 degrees. The angle θ2 is preferably 30 degrees or more and less than 90 degrees. The angle θ1 is preferably 20 degrees or more and less than 90 degrees. P1 and P2 are parallel.

[0026] 4(a) to 4(e) are diagrams illustrating a method for manufacturing the light emitting device 1 according to the first embodiment. Fig. 4(a) is a cross-sectional view showing a state in which the light emitting element 11 has been die-bonded and wire-bonded to the substrate 10A, (b) is a cross-sectional view showing a state in which the molding die D is being placed, (c) is a cross-sectional view showing a state in which the molding die D has been filled with a sealing resin, (d) is a cross-sectional view showing a state in which the molding die D has been removed, and (e) is a cross-sectional view of the completed light emitting device 1. For ease of explanation, Figs. 4(a) to 4(e) simply illustrate the shape of the molding die D and the relative positions of the light emitting element 11 and the molding die D.

[0027] First, as shown in FIG. 4(a), the light-emitting elements 11 are die-bonded at a predetermined pitch to predetermined positions on the aggregate substrate 10A using, for example, a die bonder machine, and wires 103 are wire-bonded to the patterns on the aggregate substrate 10A to establish electrical continuity.

[0028] Next, as shown in FIG. 4(b), a molding die (metal mold) D for forming the light-transmitting sealing member 12 in which the base portion 13 and the emitted light adjusting portion 14 are integrated is aligned with the aggregate substrate 10A.

[0029] 4(c), a molding die D is placed on the aggregate substrate 10A, and a light-transmitting sealing resin is filled between the aggregate substrate 10A and the molding die D. The sealing resin is then heated for a predetermined time to solidify. As the sealing resin solidifies, the base 13 and the emitted light adjustment part 14 are formed on the aggregate substrate 10A.

[0030] Next, as shown in FIG. 4(d), the molding die D is removed. At this time, since the angle θ3 (not shown in FIG. 4) formed between the upper surface of the base 13 of the emitted light adjustment section 14 and the third tapered section 18 is less than 90 degrees, the emitted light adjustment section 14 is easily removed from the molding die D. Next, the demolded aggregate substrate 10A and sealing resin are diced (cut) along the cut line X. As a result, the light emitting device 1 is completed with one light emitting element 11 mounted on the substrate 10, as shown in FIG. 4(e).

[0031] In the light-emitting device 1 according to the first embodiment, the emitted light adjustment section 14 is integrally formed with the base 13 by the translucent sealing member 12. The emitted light adjustment section 14 includes a lens section 15 at the top, a first tapered section 16 connected to the lens section, a second tapered section 17 connected to the first tapered section 16, and a third tapered section 18 connected to the second tapered section 17 and the base 13. The angle θ3 between the top surface P2 of the base 13 and the third tapered section 18 is greater than or equal to 75 degrees and less than 90 degrees. This allows the light-emitting device 1 to easily remove the emitted light adjustment section 14 from the mold while maintaining directional characteristics within a predetermined range even when the light-emitting element 11 is misaligned. That is, the light-emitting device 1 can improve robustness against misalignment of the light-emitting element 11. In particular, the light-emitting device 1 can improve robustness against misalignment of the light-emitting element 11 when the light-emitting device 1 itself is miniaturized.

[0032] Furthermore, in the light emitting device 1, the angle θ2 that the second tapered portion 17 makes with respect to a plane P1 parallel to the substrate 10 is equal to or greater than 30 degrees and less than 90 degrees. This allows the light emitting device 1 to maintain the directional characteristics within a predetermined range even when the light emitting element 11 is misaligned. In particular, the light emitting device 1 can further improve its robustness against misalignment of the light emitting element 11 by setting the angle θ3 to be equal to or greater than 75 degrees and less than 90 degrees, and the angle θ2 to be equal to or greater than 30 degrees and less than 90 degrees.

[0033] Furthermore, in the light emitting device 1, the angle θ1 that the first tapered portion 16 makes with respect to a plane P1 parallel to the substrate 10 is equal to or greater than 20 degrees and less than 90 degrees. This allows the light emitting device 1 to maintain the directional characteristics within a predetermined range even when the light emitting element 11 is misaligned. In particular, the light emitting device 1 can further improve its robustness against misalignment of the light emitting element 11 by setting the angle θ3 to be equal to or greater than 75 degrees and less than 90 degrees, the angle θ2 to be equal to or greater than 30 degrees and less than 90 degrees, and the angle θ1 to be equal to or greater than 20 degrees and less than 90 degrees.

[0034] Furthermore, in the light emitting device 1, the first tapered portion 16, the second tapered portion 17, and the third tapered portion 18 have a conical shape. This makes it easy to form each tapered portion using the forming mold (metal mold) D in the method for manufacturing the light emitting device 1.

[0035] Furthermore, the light emitting device 1 has a base 13 that is rectangular parallelepiped-shaped and has side surfaces formed by dicing. This allows a method of manufacturing the light emitting device 1 to manufacture a plurality of light emitting devices 1 at once using a molding die (metal mold) D and an assembly substrate 10A. Furthermore, since the base 13 is formed from the light-transmitting sealing member 12, the light emitting device 1 circulates light by the side surfaces of the base 13, thereby improving robustness against misalignment of the light emitting element 11.

[0036] (Embodiment 2) Fig. 5 is a perspective view of the light emitting device 2 according to the second embodiment, Fig. 6 is a top view of the light emitting device 2 according to the second embodiment, and Fig. 7 is a cross-sectional view taken along the line B-B' shown in Fig. 5. The light emitting device 2 differs from the first embodiment in that the emitted light adjusting section 14' has an elliptical shape in a plan view. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted where appropriate.

[0037] The light emitting device 2 includes a substrate 10, a light emitting element 11, a light-transmitting sealing member 12', and the like.

[0038] The light-transmitting sealing member 12' has a base 13 and an emitted light adjusting portion 14'. The base 13 and the emitted light adjusting portion 14' are integrally formed.

[0039] The emitted light adjustment unit 14' adjusts the emitted light from the light emitting element 11 so as to maintain the directional characteristics of the emitted infrared light within a predetermined range even when the light emitting element 11 is misaligned. The emitted light adjustment unit 14' is disposed above the light emitting element 11 at a position where the light emitting element 11 fits inside it in a planar view. The emitted light adjustment unit 14' has an elliptical shape in a planar view, with the X-axis direction as the major axis and the Z-axis direction as the minor axis. Because the emitted light adjustment unit 14' has an elliptical shape in a planar view, when forming the emitted light adjustment unit 14', it is easy to accommodate the wire 103 inside the emitted light adjustment unit 14'.

[0040] The emitted light adjustment section 14' has a top lens section 15', a first tapered section 16' connected to the lens section 15', a second tapered section 17' connected to the first tapered section 16', and a third tapered section 18' connected to the second tapered section 17' and the base section 13.

[0041] Lens portion 15' is disposed at a position where light emitting element 11 can be accommodated therein in plan view. Lens portion 15' has an elliptical shape with the major axis in the X-axis direction and the minor axis in the Z-axis direction in plan view, and preferably has a major axis length that allows light emitting element 11 to be accommodated even when light emitting element 11 is arranged shifted by a predetermined distance (0.1 millimeters (hereinafter, millimeters will be referred to as "mm") in the X-axis direction.

[0042] The first tapered portion 16' and the second tapered portion 17' collect the light from the light emitting element 11 and emit the collected light.

[0043] The third tapered portion 18' condenses and emits light from the light-emitting element 11. The third tapered portion 18' makes it easier to remove the emitted light adjustment portion 14' from the mold when forming it. Furthermore, the third tapered portion 18' circulates light reflected within the emitted light adjustment portion 14 and the base portion 13 even when the light-emitting element 11 is misaligned.

[0044] As in the first embodiment, the angle θ3 is preferably equal to or greater than 75 degrees and less than 90 degrees. The angle θ2 is preferably equal to or greater than 30 degrees and less than 90 degrees. The angle θ1 is preferably equal to or greater than 20 degrees and less than 90 degrees.

[0045] In the light emitting device 2 according to the second embodiment, the angle θ3 is equal to or greater than 75 degrees and less than 90 degrees, thereby improving robustness against misalignment of the light emitting element 11. In particular, the light emitting device 2 has the angle θ3 equal to or greater than 75 degrees and less than 90 degrees, and the angle θ2 equal to or greater than 30 degrees and less than 90 degrees, thereby improving robustness against misalignment of the light emitting element 11. Furthermore, the light emitting device 2 has the angle θ3 equal to or greater than 75 degrees and less than 90 degrees, the angle θ2 equal to or greater than 30 degrees and less than 90 degrees, and the angle θ1 equal to or greater than 20 degrees and less than 90 degrees, thereby further improving robustness against misalignment of the light emitting element 11.

[0046] Furthermore, in the light emitting device 2 according to the second embodiment, the emitted light adjustment section 14' has an elliptical shape in a plan view. As a result, even if the light emitting element 11 is misaligned in the major axis direction, the emitted light adjustment section 14', particularly the lens section 15', is disposed above the light emitting element 11, thereby improving robustness against misalignment of the light emitting element 11.

[0047] (The range of θ1 to θ3 and the radiation intensity ratio) FIG. 8(a) is a diagram showing the range of α degrees and the range of β degrees on the left and right with respect to the center O of the output light adjustment unit 14 when the center of the light-emitting element 11 is positioned directly below the output light adjustment unit 14 in the light-emitting device 1 according to the first embodiment. FIG. 8(b) is a diagram showing the range of α degrees and the range of β degrees on the left and right with respect to the center O of the output light adjustment unit 14 when the center of the light-emitting element 11 is positioned 0.1 mm off-center in the X-axis direction (to the left in the figure) from directly below the output light adjustment unit 14 in the light-emitting device 1 according to the first embodiment. The range of α degrees on the left and right in FIG. 8(a) is defined as range R1α, and the range of β degrees on the left and right is defined as range R1β. The range of α degrees on the left and right in FIG. 8(b) is defined as range R1α', and the range of β degrees on the left and right is defined as range R1β'. Note that α and β are each an arbitrary angle. For example, α is 30 degrees and β is 40 degrees. The 0.1 mm represents the distance of misalignment that may occur due to manufacturing constraints.

[0048] 9(a) is a diagram showing the range of α degrees to the left and the range of β degrees to the right and the left, based on the center O of the output light adjustment unit 14' when the center of the light-emitting element 11 is positioned directly below the output light adjustment unit 14' in the light-emitting device 2 according to embodiment 2, and Fig. 9(b) is a diagram showing the range of α degrees to the left and the range of β degrees to the left and the right, based on the center O of the output light adjustment unit 14' when the center of the light-emitting element 11 is positioned 0.1 mm off-center in the X-axis direction (to the left in the figure) from directly below the output light adjustment unit 14' in the light-emitting device 2 according to embodiment 2. The range of α degrees to the left in Fig. 9(a) is defined as range R2α, and the range of β degrees to the left and the right is defined as range R2β, and the range of α degrees to the left and the right is defined as range R2α' and range R2β' in Fig. 9(b).

[0049] 10 is a diagram showing a range of α degrees to the left and right and a range of β degrees to the left and right with respect to the point O directly above the light-emitting element 11 in the light-emitting device 3 according to the comparative example when the center of the light-emitting element 11 is positioned in the same position as in FIG. 10 (a), and the range of α degrees to the left and right in FIG. 10 is range R3α, and the range of β degrees to the left and right is R3β. Note that the light-emitting device 3 according to the comparative example has a structure in which only the emitted light adjustment unit 14 is not included in the light-emitting device 1 according to embodiment 1.

[0050] 12(a) is a diagram showing the radiant intensity ratio when θ3 is changed in the light emitting device 1 according to the first embodiment. In FIG. 12(a), "±αdeg_Ref" indicates the ratio between the minimum radiant intensity in the range R1α in FIG. 8(a) and the minimum radiant intensity in the range R3α in FIG. 10. "±βdeg_Ref" indicates the ratio between the minimum radiant intensity in the range R1β in FIG. 8(a) and the minimum radiant intensity in the range R3β in FIG. 10. "±αdeg" indicates the ratio between the minimum radiant intensity in the range R1α' in FIG. 8(b) and the minimum radiant intensity in the range R3α in FIG. 10. "±βdeg" indicates the ratio between the minimum radiant intensity in the range R1β' in FIG. 8(b) and the minimum radiant intensity in the range R3β. When measuring the radiation intensity, a light emitting device 1 was fabricated with each value fixed to the numerical values ​​shown in Fig. 11 (for example, θ1 was 68 degrees within the range of 20 degrees to 90 degrees, and θ2 was 40 degrees within the range of 30 degrees to 90 degrees), and multiple light emitting devices were fabricated with only θ3 changed in 5 degree increments from 70 degrees to 90 degrees, and the radiation intensity values ​​were measured. Note that changing θ3 inevitably changes the other numerical values ​​slightly, but the light emitting device 1 was fabricated while keeping changes other than θ3 as small as possible.

[0051] 12(a), it can be seen that when θ3 is 75 degrees to 90 degrees, the radiation intensity ratio is 110% or more. That is, when the center of the light-emitting element 11 is positioned 0.1 mm shifted to the left from directly below the emitted light adjustment unit 14, it is possible to improve the radiation intensity by 10% or more for "±αdeg" and "±βdeg" compared to a configuration not having the emitted light adjustment unit 14.

[0052] FIG. 12(b) shows the radiant intensity ratio when θ3 is changed in the light-emitting device 2 according to the second embodiment. In FIG. 12(b), the terms "±αdeg_Ref," "±βdeg_Ref," "±αdeg," and "±βdeg" are the same as the terms "±αdeg_Ref," "±βdeg_Ref," "±αdeg," and "±βdeg" in FIG. 12(a), respectively, except that the radiant intensities are measured for the ranges R2α, R2β, R2α', and R2β' in FIG. 9, respectively. The measurement method was also the same as in FIG. 12(a). That is, a light-emitting device 2 was fabricated with each value fixed to the values ​​shown in FIG. 11 (e.g., θ1 was 40 degrees and θ2 was 77 degrees), and multiple light-emitting devices were fabricated with only θ3 varied in 5-degree increments from 70 degrees to 90 degrees, and the radiant intensities were measured. Here, as in FIG. 12(a), the light-emitting device 2 was fabricated while keeping only θ3 as much as possible unchanged.

[0053] 12(b), it can be seen that when θ3 is between 75 degrees and 90 degrees, the radiation intensity ratio is 110% (even more so 130%) or more. That is, when the center of the light-emitting element 11 is positioned 0.1 mm shifted to the left from directly below the emitted light adjustment section 14', it is possible to improve the radiation intensity by 10% (even more so 30%) or more for "±αdeg" and "±βdeg" compared to a configuration that does not have the emitted light adjustment section 14'.

[0054] 12(a) and (b), it is believed that when θ3 is less than 75 degrees, the light-circulating function of the third tapered portions 18, 18' is reduced when the light-emitting element 11 is misaligned, resulting in a reduction in radiation intensity. For example, as shown in FIG. 12(b), when the light-emitting element 11 is misaligned, the distance between the light-emitting element 11 and the third tapered portion 18 becomes uneven. However, when θ3 is close to 90 degrees, the third tapered portion 18 functions similarly to the side surface of the base portion 13, circulating (reflecting at the side surface) the light emitted from the light-emitting element 11 and suppressing a reduction in radiation intensity. However, when θ3 is less than 75 degrees, it is believed that the function of the third tapered portion 18 as a side surface is reduced, resulting in a reduction in radiation intensity. On the other hand, if θ3 exceeds 90 degrees, it becomes difficult to remove the emitted light adjustment sections 14, 14' from the mold during manufacturing of the light emitting device 1, so it is preferable that θ3 is equal to or greater than 75 degrees and less than 90 degrees.

[0055] FIG. 13(a) shows the radiant intensity ratio when θ2 is changed in the light-emitting device 1 according to the first embodiment. In FIG. 13(a), the terms "±αdeg_Ref," "±βdeg_Ref," "±αdeg," and "±βdeg" are the same as those in FIG. 12(a), respectively. The measurements were similar to those in FIG. 12(a), except that multiple light-emitting devices were fabricated with only θ2 varied in predetermined-degree increments from 30 to 90 degrees, and the radiant intensity values ​​were measured. Specifically, a light-emitting device 1 was fabricated with each value fixed as shown in FIG. 11 (θ1 was 68 degrees and θ3 was 85 degrees), and multiple light-emitting devices were fabricated with only θ2 varied in predetermined-degree increments from 30 to 90 degrees, and the radiant intensity values ​​were measured. The light-emitting device 1 was fabricated while minimizing changes other than θ2 as much as possible.

[0056] 13(a), it can be seen that when θ2 is between 30 degrees and 90 degrees, the radiation intensity ratio is 110% (even more so, 120%) or more. That is, when the center of the light-emitting element 11 is positioned 0.1 mm shifted to the left from directly below the emitted light adjustment unit 14, it is possible to improve the radiation intensity by 10% (even more so, 20%) or more for "±αdeg" and "±βdeg" compared to a configuration that does not have the emitted light adjustment unit 14.

[0057] FIG. 13(b) shows the radiant intensity ratio when θ2 is changed in the light-emitting device 2 according to the second embodiment. In FIG. 13(b), the terms "±αdeg_Ref," "±βdeg_Ref," "±αdeg," and "±βdeg" are the same as the terms "±αdeg_Ref," "±βdeg_Ref," "±αdeg," and "±βdeg" in FIG. 13(a), respectively, except that the radiant intensities are measured for the ranges R2α, R2β, R2α', and R2β' in FIG. 9, respectively. The measurements were also performed in the same manner as in FIG. 13(a). Specifically, a light-emitting device 2 was fabricated with each value fixed to the values ​​shown in FIG. 11 (θ1 was 40 degrees and θ3 was 85 degrees), and multiple light-emitting devices were fabricated with only θ2 varied in predetermined degree increments from 30 degrees to 90 degrees, and the radiant intensities were measured. As with FIG. 13(a), the light-emitting device 2 was fabricated while keeping only θ2 as much as possible unchanged.

[0058] 13(b), it can be seen that when θ2 is between 30 degrees and 90 degrees, the radiation intensity ratio is 110% or more. That is, when the center of the light-emitting element 11 is positioned 0.1 mm shifted to the left from directly below the emitted light adjustment section 14′, it is possible to improve the radiation intensity by 10% or more for “±α°” and “±β°” compared to a configuration that does not have the emitted light adjustment section 14′.

[0059] Considering the reasons for the results shown in Figures 13(a) and (b), if θ2 is less than 30 degrees, when the light-emitting element 11 is misaligned, the amount of light reflected by the second tapered portions 17, 17' toward the light-emitting element 11 increases, resulting in a decrease in radiation intensity. For example, as shown in Figure 8(b), when the light-emitting element 11 is misaligned, the second tapered portion 17 is located directly above the light-emitting element 11. In this case, it is presumed that the amount of light emitted from the upper part of the light-emitting element 11 and reflected by the second tapered portion 17 is greater than when the light-emitting element 11 is not misaligned. In particular, as θ2 approaches 0 degrees, the amount of light reflected by the second tapered portion 17 toward the light-emitting element 11 increases relatively, resulting in a decrease in radiation intensity of light emitted from the emitted light adjustment portion 14. On the other hand, if θ2 exceeds 90 degrees, it is presumed that the light-collecting function decreases when the light-emitting element 11 is misaligned. In light of these factors, it is preferable that θ2 be greater than or equal to 30 degrees and less than 90 degrees.

[0060] FIG. 14 shows the radiant intensity ratio when θ1 is changed in the light-emitting device 1 according to the first embodiment. In FIG. 14, the terms “±αdeg_Ref,” “±βdeg_Ref,” “±αdeg,” and “±βdeg” are the same as the terms “±αdeg_Ref,” “±βdeg_Ref,” “±αdeg,” and “±βdeg” in FIG. 12(a), respectively. The measurements were similar to those in FIG. 12(a), except that multiple light-emitting devices were fabricated with only θ1 varied in 10-degree increments from 20 to 90 degrees, and the radiant intensity values ​​were measured. That is, a light-emitting device 1 was fabricated with each value fixed as shown in FIG. 11 (θ2 was 40 degrees and θ3 was 85 degrees), and multiple light-emitting devices were fabricated with only θ1 varied in 10-degree increments from 20 to 90 degrees, and the radiant intensity values ​​were measured. In this case, the light-emitting device 1 was fabricated while keeping the values ​​other than θ1 as small as possible.

[0061] 14, it can be seen that when θ1 is between 20 degrees and 90 degrees, the radiation intensity ratio is 110% or more. That is, when the center of the light-emitting element 11 is positioned 0.1 mm shifted to the left from directly below the emitted light adjustment unit 14, it is possible to improve the radiation intensity by 10% or more for "±αdeg" and "±βdeg" compared to a configuration not having the emitted light adjustment unit 14.

[0062] When considering the reason for the results in Figure 14, it is believed that if θ1 is less than 20 degrees, when the light-emitting element 11 is misaligned, the amount of light reflected by the first tapered portion 16 toward the light-emitting element 11 increases, resulting in a decrease in radiation intensity. That is, as with θ2, when the light-emitting element 11 is misaligned, the first tapered portion 16 is located directly above the light-emitting element 11, which increases the amount of light reflected by the first tapered portion 16 toward the light-emitting element 11, resulting in a decrease in radiation intensity. On the other hand, if θ1 exceeds 90 degrees, it is believed that the light-collecting function decreases when the light-emitting element 11 is misaligned. In light of these factors, it is preferable that θ1 be greater than or equal to 20 degrees and less than 90 degrees.

[0063] It should be understood by those skilled in the art that various changes, substitutions, and alterations can be made to the present invention without departing from the spirit and scope of the present invention. For example, the above-described embodiments and modifications may be appropriately combined within the scope of the present invention. [Explanation of symbols]

[0064] 1, 2, 3 Light-emitting device 10 Substrate 12, 12' Translucent sealing member 13 Base 14, 14' Output light adjustment section 15, 15' lens section 16, 16' First tapered section 17, 17' Second tapered section 18, 18' Third taper section

Claims

1. A substrate; a light-emitting element disposed on the substrate; a light-transmitting sealing member that seals the light-emitting element, the light-transmitting sealing member is composed of an integrally formed base portion and an emitted light adjusting portion, the light emitting element is sealed inside the base; the emitted light adjustment unit is disposed above the light emitting element, the emitted light adjustment portion has an uppermost lens portion, a first tapered portion connected to the lens portion, a second tapered portion connected to the first tapered portion, and a third tapered portion connected to the second tapered portion and the base portion, The angle (θ3) between the upper surface of the base and the third tapered portion is greater than or equal to 75 degrees and less than 90 degrees. A light emitting device characterized by:

2. The light emitting device according to claim 1 , wherein an angle (θ2) formed by the second tapered portion with respect to a plane parallel to the substrate is equal to or greater than 30 degrees and less than 90 degrees.

3. The light emitting device according to claim 2 , wherein an angle (θ1) formed by the first tapered portion with respect to a plane parallel to the substrate is equal to or greater than 20 degrees and less than 90 degrees.

4. 4. The light emitting device according to claim 1, wherein the first tapered portion, the second tapered portion, and the third tapered portion have a conical shape.

5. 4. The light emitting device according to claim 1, wherein the base portion has a rectangular parallelepiped shape and has side surfaces formed by dicing.

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