Light emitting device

Abstract

To provide a light emitting device in which a conductive member supplying power is less likely to affect light distribution characteristics.SOLUTION: A light emitting device 1 includes: a mounting board 10 including a pair of first arrangement parts 21 and 22 formed of through holes or notches, the first arrangement parts being capable of having a conductive member 90 for supplying power arranged thereon; and a circuit board 11 including a pair of second arrangement parts 23 and 24 formed of through holes or notches, the second arrangement parts being capable of having the conductive member 90 arranged on the pair of first arrangement parts 21 and 22 arranged thereon, and a pair of wiring patterns 12a and 12b which are connectable to the conductive member 90 arranged on the pair of second arrangement parts 23 and 24, the circuit board being arranged on the mounting board 10; and a light emitting element 14 connected to the pair of wiring patterns 12a and 12b and mounted on the mounting board 10. The pair of first arrangement parts 21 and 22 is arranged to surround at least a part of peripheries of the pair of second arrangement parts 23 and 24, respectively, in plan view.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Various techniques are known for improving the light-emitting characteristics and reliability of light-emitting devices that use light-emitting diode (LED) dies as light-emitting elements. Patent Document 1 describes a light-emitting device having an index wire formed from an insulator and positioned at a distance greater than the creepage distance from the outer edge of the substrate. The light-emitting device described in Patent Document 1 uses the index wire positioned at a distance greater than the creepage distance from the outer edge of the substrate as a reference, thereby arranging a conductive member such as a lead wire that supplies power from an external power source, thereby making it easy to ensure the creepage distance between the conductive member and the outer edge of the substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-160647 Summary of the Invention [Problem to be solved by the invention]

[0004] In light-emitting devices that use LED dies as light-emitting elements, miniaturization is desired, and the distance between the light-emitting element and an electrode pad connected to a conductive member to supply power to the light-emitting device is becoming shorter.If the distance between the light-emitting element and the electrode pad becomes shorter, the conductive member may block the light emitted from the light-emitting element, which may affect the light distribution characteristics of the light-emitting device.

[0005] The present invention is intended to solve such problems, and provides a light emitting device in which the conductive member that supplies power is unlikely to affect the light distribution characteristics. [Means for solving the problem]

[0006] The light-emitting device of the present invention comprises a mounting substrate having a pair of first arrangement portions formed by through holes or notches in which conductive members for supplying power can be arranged, a pair of second arrangement portions formed by through holes or notches in which the conductive members arranged in the pair of first arrangement portions can be arranged, and a pair of wiring patterns connectable to the conductive members arranged in the pair of second arrangement portions, and a circuit board arranged on the mounting substrate; and a light-emitting element connected to the pair of wiring patterns and mounted on the mounting substrate, wherein the pair of first arrangement portions are arranged so as to surround at least a portion of the periphery of each of the pair of second arrangement portions in a planar view.

[0007] Furthermore, in the light-emitting device according to the present invention, the mounting board and the circuit board have two pairs of sides arranged opposite each other, and the pair of first arrangement portions are preferably arranged so that, in a planar view, the outer edges of at least one pair of first arrangement portions are located between the outer edges of the pair of second arrangement portions and one of the two pairs of sides, and between the outer edges of the pair of second arrangement portions and one of the two sides of the other pair of sides.

[0008] Furthermore, in the light-emitting device according to the present invention, it is preferable that the separation distance between the outer edge of the first arrangement portion and the outer edge of the second arrangement portion is equal to or greater than the minimum creepage distance between the pair of wiring patterns and the outer edge of the mounting substrate.

[0009] Furthermore, in the light emitting device according to the present invention, the pair of first arrangement portions are preferably arranged on diagonal corners of the mounting substrate.

[0010] Furthermore, in the light emitting device according to the present invention, the pair of first arrangement portions are preferably arranged near the center of one of a pair of two opposing sides of the mounting substrate.

[0011] Furthermore, in the light emitting device according to the present invention, it is preferable that the circuit board further includes a pair of electrode pads formed on each of the pair of wiring patterns.

[0012] Furthermore, in the light emitting device according to the present invention, the pair of first arrangement portions and the pair of second arrangement portions are preferably through holes formed so as to penetrate through the region surrounded by the pair of electrode pads.

[0013] Furthermore, in the light emitting device according to the present invention, the pair of first arrangement portions and the pair of second arrangement portions are preferably notches formed so as to penetrate through the region sandwiched between the pair of electrode pads.

[0014] Furthermore, in the light emitting device according to the present invention, the pair of first arrangement portions and the pair of second arrangement portions are preferably notches formed in regions adjacent to the pair of electrode pads, respectively.

[0015] Furthermore, the light emitting device according to the present invention preferably further comprises a conductive plate arranged so as to straddle each of the pair of first arrangement portions and the pair of second arrangement portions.

[0016] In addition, the lighting device of the present invention includes a pair of conductive members connectable to an external power source, a light-emitting device connected to the pair of conductive members and emitting light in response to power being supplied via the pair of conductive members, and a heat dissipation member fixed to the light-emitting device and dissipating heat generated by the light-emitting device, and the light-emitting device includes a mounting board having a pair of first arrangement portions formed by through holes or notches in which each of the pair of conductive members can be arranged, a circuit board having a pair of second arrangement portions formed by through holes or notches in which the pair of conductive members can be arranged and a pair of wiring patterns connectable to the conductive members arranged in the pair of second arrangement portions, and a light-emitting element connected to the pair of wiring patterns and mounted on the mounting board, and the pair of first arrangement portions are arranged so as to surround at least a portion of the periphery of each of the pair of second arrangement portions in a planar view. [Effects of the Invention]

[0017] The light emitting device according to the present invention can reduce the risk that the conductive member that supplies power will affect the light distribution characteristics. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1(a) is a plan view of a light emitting device according to a first embodiment, and FIG. 1(b) is a plan view of a mounting substrate provided in the light emitting device shown in FIG. [Figure 2] FIG. 2 is a partial cross-sectional view of the vicinity of a first arrangement portion shown in FIG. [Figure 3] FIG. 10(a) is a plan view of a light emitting device according to a second embodiment, and (b) is a plan view of a mounting substrate provided in the light emitting device shown in (a). [Figure 4] FIG. 10(a) is a plan view of a light emitting device according to a third embodiment, and (b) is a plan view of a mounting substrate provided in the light emitting device shown in (a). [Figure 5] FIG. 5 is a diagram showing the relationship between the width of the second arrangement portion shown in FIG. 4(a), the radius of the lead wire, and the sinking length of the lead wire. [Figure 6] FIG. 10(a) is a plan view of a light emitting device according to a fourth embodiment, and (b) is a plan view of a mounting substrate provided in the light emitting device shown in (a). [Figure 7] (a) is a plan view of the light-emitting device shown in Figure 6(a) excluding a pair of conductive plates, (b) is a plan view of the conductive plates shown in (a), (c) is a side view of the conductive plates shown in (a), and (d) is a partial side view of the light-emitting device with lead wires connected, viewed from the direction indicated by arrow A in Figure 6(a). [Figure 8] FIG. 10 is a plan view of a light emitting device according to a fifth embodiment. [Figure 9] 9 is a plan view showing the light emitting device shown in FIG. 8 with a dam material and a sealing material seen through. [Figure 10] 1A and 1B are diagrams showing a lighting device as an example of an application example of a light-emitting device according to an embodiment, in which (a) is a plan view of the lighting device, (b) is a cross-sectional view along line AA shown in (a), and (c) is an enlarged cross-sectional view of the area surrounded by dashed line B shown in (b). DETAILED DESCRIPTION OF THE INVENTION

[0019] 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.

[0020] (Configuration and Function of the Light-Emitting Device According to the First Embodiment) FIG. 1(a) is a plan view of a light emitting device according to a first embodiment, and FIG. 1(b) is a plan view of a mounting substrate provided in the light emitting device shown in FIG. 1(a).

[0021] The light emitting device 1 includes a mounting substrate 10, a circuit board 11, a pair of wiring patterns 12a and 12b, a pair of electrode pads 13a and 13b, a plurality of LED dies 14, bonding wires 15, a solder resist 16, a dam material 17, and a sealing material 18. The light emitting device 1 is a chip-on-board (COB) type light emitting device, and emits white light in response to power being supplied from an external power source via lead wires, which are conductive members connected to the pair of electrode pads 13a and 13b by solder.

[0022] The mounting substrate 10 is a metal substrate made of a metal such as aluminum. The mounting substrate 10 has a generally rectangular planar shape with two pairs of opposing sides, and has a mounting area on its surface where the LED die 14 is mounted. The mounting substrate 10 has a thickness of, for example, 0.7 mm. The mounting substrate 10 has a pair of engaging portions 10a and 10b formed at a pair of diagonal corners. The pair of engaging portions 10a and 10b engage with fastening members used when fastening the light emitting device 1 to a heat dissipation member (not shown) or the like.

[0023] Furthermore, the mounting substrate 10 has a pair of first arrangement portions 21 and 22 formed on a diagonal line connecting a pair of diagonal corners other than the diagonal corners on which the pair of engaging portions 10a and 10b are formed. The pair of first arrangement portions 21 and 22 have the same shape and size, have a circular planar shape, and are through-holes formed to penetrate from the top surface to the bottom surface of the mounting substrate 10, into which lead wires for supplying power from an external power source are inserted. The diameters of the pair of first arrangement portions 21 and 22 are determined so that when the lead wires for supplying power from the external power source are arranged, the separation distance between the conductors of the lead wires and the mounting substrate is equal to or greater than the minimum creepage distance between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 10.

[0024] Fig. 2 is a partial cross-sectional view of the vicinity of the first arrangement portion 21. The partial cross-sectional view of the vicinity of the first arrangement portion 22 is similar to Fig. 2, and therefore illustration and description thereof will be omitted.

[0025] The lead wire 90 is arranged in the first arrangement portion 21. The lead wire 90 has a conductor 91 such as a tin-plated annealed copper wire and a covering material 92 formed of an insulator such as a flame-retardant cross-linked polyolefin. The conductor 91 of the lead wire 90 may be a solid wire or a twisted wire. The lead wire 90 is arranged below the light emitting device 1 so that a tip of the conductor 91 protrudes from the upper surface of the circuit board 11. The lead wire 90 is electrically connected to the plurality of LED dies 14 by joining the tip of the conductor 91 protruding from the upper surface of the circuit board 11 to the circuit board 11 with solder such as Sn-Ag-Cu solder, which has a melting temperature of approximately 215°C to 220°C.

[0026] The radius R of the first arrangement portion 21 is the distance L between the conductor 91 of the lead wire 90 and the mounting substrate 10, that is, the inner wall 21a, which is the side surface of the mounting substrate 10 that contacts the outer edge of the first arrangement portion 21. D is the creepage distance L C The outer edge of the first arrangement portion 21 is the side surface of the first arrangement portion 21 where the first arrangement portion 21 contacts the mounting board 10. Similarly, the outer edge of the first arrangement portion 22 is the side surface of the first arrangement portion 22 where the first arrangement portion 22 contacts the mounting board 10. The creepage distance L Cis the creepage distance between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 10. That is, the separation distance L between the wiring patterns 12a and 12b and the outer edge of the circuit board 11 C1 and the separation distance L between the upper surface of the mounting substrate 10 and the upper surface of the circuit board 11. C2 This is determined depending on the voltage applied to the lead wire 90, the degree of pollution in the environment in which the light emitting device 1 is used, and the material that forms the circuit board.

[0027] The circuit board 11 is an insulating substrate made of a glass epoxy material or the like, and has a generally rectangular planar shape with two pairs of opposing sides. It has an outer edge with the same planar shape as the mounting board 10. The circuit board 11 is placed on the mounting board 10 by being adhered to the surface of the mounting board 10 with an adhesive 19, and a circular opening 11a is formed in the center. The fact that the mounting board 10 and the circuit board 11 have the same planar shape means that their planar shapes are identical except for the shape of the side surface of the mounting board 10 that contacts the outer edges of the first arrangement portions 21 and 22 and the side surface of the circuit board 11 that contacts the outer edges of the second arrangement portions 23 and 24. The thickness of the circuit board 11 is, for example, 0.1 mm, and the thickness of the adhesive 19 is, for example, 0.025 mm.

[0028] A pair of wiring patterns 12a and 12b are formed on the upper surface of the circuit board 11 so as to surround the opening 11a, and a pair of electrode pads 13a and 13b are formed near two diagonally opposite corners. The pair of electrode pads 13a and 13b have the same shape and size and have an annular planar shape. The pair of wiring patterns 12a and 12b are made of a conductive metal such as copper, and have a thickness of, for example, 0.035 mm.

[0029] Furthermore, a pair of second arrangement portions 23 and 24 are arranged on the circuit board 11 so as to be surrounded by the pair of electrode pads 13a and 13b, respectively. The pair of second arrangement portions 23 and 24 are formed so as to penetrate from the upper surface to the lower surface of the circuit board 11, and are through holes into which the conductors 91 of the lead wires 90 are inserted. The pair of second arrangement portions 23 and 24 have the same shape and size, have circular planar shapes, and are arranged so that the centers of the pair of electrode pads 13a and 13b and the centers of the pair of second arrangement portions 23 and 24 coincide with each other when the light emitting device 1 is viewed in a plane.

[0030] When the light emitting device 1 is viewed from above, each of the pair of second arrangement portions 23 and 24 is arranged so as to be surrounded by the inner wall of the mounting substrate 10 that contacts the outer edges of each of the pair of first arrangement portions 21 and 22. The pair of first arrangement portions 21 and 22 is arranged so that the outer edges of each of the pair of first arrangement portions 21 and 22 are located between the outer edges of each of the pair of second arrangement portions 23 and 24 and two pairs of two sides of the mounting substrate 10 and the circuit board 11 in a plan view. The pair of second arrangement portions 23 and 24 are arranged so that the centers of each of the pair of first arrangement portions 21 and 22 coincide with the centers of each of the pair of second arrangement portions 23 and 24. The diameters of the pair of second arrangement portions 23 and 24 are determined so that the conductor 91 of the lead wire 90 can pass through them but the coating material 92 of the lead wire 90 cannot. Furthermore, the inner wall, which is the side surface of the circuit board 11 that contacts the outer edges of the pair of second arrangement portions 23 and 24, is not provided with a conductor such as metal plating and is formed of an insulating material. The outer edge of the second arrangement portion 23 is the side surface of the second arrangement portion 23 where the second arrangement portion 23 contacts the circuit board 11. Similarly, the outer edge of the second arrangement portion 24 is the side surface of the second arrangement portion 24 where the second arrangement portion 24 contacts the circuit board 11.

[0031] The distance between the outer edges of the pair of first arrangement portions 21 and 22 and the outer edges of the pair of second arrangement portions 23 and 24 is the creepage distance L between the wiring patterns 12a and 12b and the outer edges of the mounting substrate 10. CThe distance between the outer edge of each of the pair of first arrangement portions 21 and 22 and the outer edge of each of the pair of second arrangement portions 23 and 24 may be determined to be equal to or greater than the minimum value of the creepage distance L between the wiring patterns 12 a and 12 b and the outer edge of the mounting substrate 10. C When the distance L between the conductor 91 of the lead wire 90 and the mounting substrate 10 is determined to be equal to or greater than the minimum value of D is the creepage distance L C This allows for more stable setting so that the minimum value is equal to or greater than the specified value.

[0032] The electrode pad 13a is an anode electrode, and the electrode pad 13b is a cathode electrode. The pair of electrode pads 13a and 13b are connected to an external power supply (not shown) via a pair of lead wires 90 connected by solder.

[0033] The LED die 14, also referred to as a light-emitting element, has a semiconductor layer on an insulating base. The LED die 14 is mounted on the mounting substrate 10 exposed through the opening 11a via an insulating die-bonding material. The light-emitting device 1 has 40 LED dies 14. The die-bonding material used to mount the LED dies 14 is an epoxy-based adhesive, a silicone-based adhesive, or another material that is not easily affected by the heat that accompanies soldering.

[0034] The bonding wire 15 is made of a conductive material such as gold and connects the cathode and anode of adjacent LED dies 14. The bonding wire 15 also connects the LED dies 14 adjacent to the outer edge of the opening 11a to the wiring patterns 12a and 12b. In the light emitting device 1, five rows of eight LED dies 14 connected in series via bonding wires 15 are connected in parallel to the wiring patterns 12a and 12b. However, in the LED die according to the embodiment, the number of LED dies 14 connected in series and the number of rows connected in parallel may be determined as appropriate.

[0035] The solder resist 16 is a heat-resistant insulating resin such as epoxy resin, and is arranged on the circuit board 11 so as to cover the outside of the opening 11a and the entire surface of the pair of wiring patterns 12a and 12b except for the pair of electrode pads 13a and 13b. The thickness of the solder resist 16 is, for example, 0.010 mm to 0.020 mm.

[0036] The dam material 17 is an insulating synthetic resin made of a synthetic resin such as silicone resin containing a filler such as silica, and is arranged along the outer edge of the opening 11a so as to cover the wiring patterns 12a and 12b. The dam material 17 reflects the blue light emitted from the LED die 14 and emits it upward in the direction opposite to the mounting substrate 10 of the LED die 14.

[0037] The encapsulant 18 is a colorless, transparent, insulating synthetic resin such as epoxy resin or silicone resin, and is disposed inside the dam material 17 to integrally cover the LED die 14 and the bonding wire 15. By forming the dam material 17 and the encapsulant 18 from insulating synthetic resin, the dielectric strength voltage between the wiring patterns 12a and 12b and the mounting area of ​​the mounting substrate 10 on which the LED die 14 is mounted becomes sufficiently larger than the dielectric strength voltage between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 10. The encapsulant 18 is made of a material such as Y3Al5O 12 The light emitting device 1 emits white light by mixing blue light from the LED die 14 with green and red phosphor particles such as CaAlSiN3:Eu (Yttrium Aluminum Garnet, YAG) and red phosphor particles such as CaAlSiN3:Eu (CASN). The green and red phosphor particles may be deposited to cover at least a portion of the surface of the mounting substrate 10 and the surfaces and sides of the LED die 14, or may be dispersed in the encapsulant 18. The light emitting device 1 emits white light by mixing blue light from the LED die 14 with green and red light obtained by exciting the green and red phosphors with a portion of the blue light. The phosphors mixed in the encapsulant 18 are not limited to the above two types of phosphors, and any combination of phosphors of other colors may be selected.

[0038] A method for manufacturing the light emitting device 1 will be described. First, in an aggregate substrate preparation step, an aggregate substrate is prepared in which a plurality of bonded mounting substrates 10 and a circuit board 11 are integrated. Next, in a light emitting element mounting step, a plurality of LED dies 14 are mounted via a die bond material at predetermined positions on the mounting substrates 10 included in the aggregate substrate. Next, in a wire bonding step, bonding wires 15 are used to wire bond between the plurality of LED dies 14 and between the plurality of LED dies 14 and the wiring patterns 12a and 12b. Next, in a dam material placement step, a dam material 17 is placed so as to surround the mounting substrate 10. Next, in a sealing material placement step, a sealing material 18 is placed in the area surrounded by the dam material 17. Then, in a cutting step, the aggregate substrate is cut to manufacture a plurality of light emitting devices 1.

[0039] (Actions and Effects of the Light Emitting Device According to the First Embodiment) In the light emitting device 1, by connecting the lead wire 90 to the light emitting device 1 with only the tip of the conductor 91 protruding from the upper surface of the circuit board 11, the lead wire 90 can be connected to the light emitting device 1 without the covering material 92 of the lead wire 90 protruding above the circuit board 11. By connecting the lead wire 90 to the light emitting device 1 without the covering material 92 of the lead wire 90 protruding above the circuit board 11, the amount of light reflected by the lead wire 90 is reduced, and a decrease in light emitting efficiency is suppressed.

[0040] Furthermore, the light emitting device 1 has the tip of the conductor 91 protruding from the upper surface of the circuit board 11 via the first arrangement portions 21 and 22 and the second arrangement portions 23 and 24, and the tip of the conductor 91 is solder-connected to a pair of electrode pads 13a and 13b, making solder connection easy.

[0041] In addition, in the light emitting device 1, the radius R of the first arrangement portion 21 is set to be equal to or smaller than the distance L between the conductor 91 of the lead wire 90 and the inner wall 21a of the first arrangement portion 21. D is the creepage distance L C Since the radius of the first arrangement portion 22 is determined to be equal to the radius R of the first arrangement portion 21, the dielectric strength voltage between the mounting substrate 10 and the conductor 91 of the lead wire 90 can be ensured.

[0042] (Configuration and Function of Light-Emitting Device According to Second Embodiment) Fig. 3(a) is a plan view of a light emitting device according to a second embodiment, and Fig. 3(b) is a plan view of a mounting substrate of the light emitting device shown in Fig. 3(a). In the light emitting device 2, the first and second arrangement portions in which the lead wires 90 are arranged are formed as notches extending toward the opposing sides instead of the first arrangement portions 21 and 22 and the second arrangement portions 23 and 24 which are through holes.

[0043] The light emitting device 2 differs from the light emitting device 1 in that it has a mounting substrate 30, a circuit board 31, and a pair of electrode pads 33a and 33b instead of the mounting substrate 10, the circuit board 11, and the pair of electrode pads 13a and 13b. The configurations and functions of the components of the light emitting device 2 other than the mounting substrate 30, the circuit board 31, and the pair of electrode pads 33a and 33b are the same as the configurations and functions of the components of the light emitting device 1 that are given the same reference numerals, and therefore detailed description thereof will be omitted here. The light emitting device 2 emits white light in response to power being supplied from an external power source via lead wires 90 that are soldered to the pair of electrode pads 33a and 33b.

[0044] Like the mounting substrate 10, the mounting substrate 30 is a metal substrate made of a metal such as aluminum, has a substantially rectangular planar shape with two pairs of opposing sides, and has a mounting area on its surface where the LED die 14 is mounted. The thickness of the mounting substrate 30 is, for example, 0.7 mm, like the mounting substrate 10. The mounting substrate 30 has a pair of engaging portions 30a and 30b formed at a pair of diagonal corners to engage with fastening members used when fastening the mounting substrate to a heat dissipation member or the like.

[0045] The mounting substrate 30 also has a pair of first arrangement portions 36 and 37 formed on a diagonal line connecting a pair of diagonal corners other than the diagonal corners on which the pair of engaging portions 30a and 30b are formed. The pair of first arrangement portions 36 and 37 have the same shape and size, and have a planar shape in which a semicircular portion and a rectangular portion, one side of which has the same length as the diameter of the semicircular portion, are connected by the diameter of the semicircular portion and one side of the rectangular portion, and are notches formed to penetrate from the upper surface to the lower surface of the mounting substrate 30 and extend from one side of the mounting substrate 30 to the opposing side. Lead wires 90 are arranged in the pair of first arrangement portions 36 and 37.

[0046] The length of one side of the rectangular portion of the first arrangement portions 36 and 37 and the diameter of the semicircular portion are also referred to as the width of the first arrangement portions 36 and 37. The width of the pair of first arrangement portions 36 and 37 is the distance L between the conductor 91 of the lead wire 90 and the mounting substrate 30, i.e., the inner wall, which is the side surface of the mounting substrate 30 that contacts the outer edge of each of the first arrangement portions 36 and 37. D The creepage distance L between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 30 is C The outer edge of the first arrangement portion 36 is the side surface of the first arrangement portion 36 where the first arrangement portion 36 comes into contact with the mounting board 30. Similarly, the outer edge of the first arrangement portion 37 is the side surface of the first arrangement portion 37 where the first arrangement portion 37 comes into contact with the mounting board 30. Note that the pair of first arrangement portions 36 and 37 may be formed to extend along a diagonal line.

[0047] The circuit board 31 is an insulating board made of a glass epoxy material or the like, has an outer edge with the same planar shape as the mounting board 30, is bonded to the surface of the mounting board 30 with an adhesive, and has a circular opening 31a formed in the center. The thickness of the circuit board 31 is, for example, 0.1 mm, similar to that of the circuit board 11. The mounting board 30 and the circuit board 31 having the same planar shape means that their planar shapes are the same except for the shape of the side surface of the mounting board 30 that is in contact with the outer edges of the first arrangement portions 36 and 37 and the side surface of the circuit board 31 that is in contact with the outer edges of the second arrangement portions 38 and 39.

[0048] A pair of wiring patterns 12a and 12b are formed on the upper surface of the circuit board 31 so as to surround the opening 31a, and a pair of electrode pads 33a and 33b are formed near two diagonally opposite corners. The pair of electrode pads 33a and 33b have the same shape and size and have a U-shaped planar shape in which a semicircular arc portion and a pair of rectangular portions connected to the ends of the semicircular arc portion are connected by the width of the semicircular arc portion and one side of each of the pair of rectangular portions.

[0049] Furthermore, a pair of second arrangement portions 38 and 39 are arranged on the circuit board 31. When the light emitting device 2 is viewed in a plane, a portion of each of the pair of second arrangement portions 38 and 39 is arranged so as to be sandwiched between the pair of rectangular portions of the pair of electrode pads 33a and 33b. The pair of second arrangement portions 38 and 39 have the same shape and size, and have a planar shape in which a semicircular portion and a rectangular portion, one side of which has the same length as the diameter of the semicircular portion, are connected by the diameter of the semicircular portion and one side of the rectangular portion, and are arranged so that the center of each semicircular portion of the pair of electrode pads 33a and 33b and the center of each semicircular portion of the second arrangement portions 38 and 39 coincide with each other when the light emitting device 2 is viewed in a plane.

[0050] The pair of second arrangement portions 38 and 39 are notches that are formed to penetrate from the upper surface to the lower surface of the circuit board 31 and extend from one side of the circuit board 31 to the opposing side. Lead wires 90 are arranged in the pair of second arrangement portions 38 and 39. When the light emitting device 2 is viewed from above, each of the pair of second arrangement portions 38 and 39 is arranged so as to be sandwiched between inner walls, which are side surfaces of the mounting board 30 that contact the outer edges of the pair of first arrangement portions 36 and 37, respectively, and is arranged so that the center of each semicircular portion of the pair of second arrangement portions 38 and 39 coincides with the center of each semicircular portion of the pair of first arrangement portions 36 and 37. The pair of first arrangement portions 36 and 37 are arranged such that, in a plan view, the outer edges of the pair of second arrangement portions 38 and 39 are positioned between the outer edges of one pair of two sides of the mounting substrate 30 and the circuit board 31, and between the outer edges of the pair of first arrangement portions 36 and 37 and one side of the other pair of two sides of the mounting substrate 30 and the circuit board 31. The length of one side of the rectangular portion of the pair of second arrangement portions 38 and 39 is determined so that the conductor 91 of the lead wire 90 can pass through but the covering material 92 cannot. Note that when the pair of first arrangement portions 36 and 37 extend along a diagonal, the pair of second arrangement portions 38 and 39 and the pair of electrode pads 33a and 33b are also formed to extend along the diagonal. Furthermore, the inner walls of the circuit board 31, which are the side surfaces of the circuit board 31 that contact the outer edges of the pair of second arrangement portions 38 and 39, are formed of an insulating material. The outer edge of the second arrangement portion 38 is the side surface of the second arrangement portion 38 where the second arrangement portion 38 contacts the circuit board 31. Similarly, the outer edge of the second arrangement portion 39 is the side surface of the second arrangement portion 39 where the second arrangement portion 39 contacts the circuit board 31.

[0051] The distance between the outer edges of the pair of first arrangement portions 36 and 37 and the outer edges of the pair of second arrangement portions 38 and 39 is the creepage distance L between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 30. C The distance between the outer edge of each of the pair of first arrangement portions 36 and 37 and the outer edge of each of the pair of second arrangement portions 38 and 39 may be determined to be equal to or greater than the minimum value of the creepage distance L between the wiring patterns 12 a and 12 b and the outer edge of the mounting substrate 30. CWhen the distance L between the conductor 91 of the lead wire 90 and the mounting substrate 30 is determined to be equal to or greater than the minimum value of D is the creepage distance L C This allows for more stable setting so that the minimum value is equal to or greater than the specified value.

[0052] The method for manufacturing the light emitting device 2 is the same as the method for manufacturing the light emitting device 1, and therefore a detailed description thereof will be omitted here.

[0053] (Functions and Effects of the Light Emitting Device According to the Second Embodiment) In the light emitting device 2, the first arrangement portions 36 and 37 and the second arrangement portions 38 and 39 are notches extending toward the opposite sides, so that the lead wires 90 can be arranged in the first arrangement portions 36 and 37 and the second arrangement portions 38 and 39 from the sides of the light emitting device 2. In the light emitting device 2, the lead wires 90 can be arranged in the first arrangement portions 36 and 37 and the second arrangement portions 38 and 39 from the sides of the light emitting device 2, so that the connection process for connecting the lead wires 90 to the light emitting device 2 is easier than the connection process for the light emitting device 1.

[0054] (Configuration and Function of Light-Emitting Device According to Third Embodiment) Fig. 4(a) is a plan view of a light emitting device according to a third embodiment, and Fig. 4(b) is a plan view of a mounting substrate included in the light emitting device shown in Fig. 4(a). In the light emitting device 3, the first and second arrangement portions are formed as notches into which the lead wires 90 are inserted from the sides of the mounting substrate and the circuit board, rather than from below the mounting substrate and the circuit board.

[0055] The light emitting device 3 differs from the light emitting device 1 in that it has a mounting substrate 40, a circuit board 41, and a pair of electrode pads 43a and 43b instead of the mounting substrate 10, the circuit board 11, and the pair of electrode pads 13a and 13b. The configurations and functions of the components of the light emitting device 3 other than the mounting substrate 40, the circuit board 41, and the pair of electrode pads 43a and 43b are the same as the configurations and functions of the components of the light emitting device 1 that are given the same reference numerals, and therefore detailed description thereof will be omitted here. The light emitting device 3 emits white light in response to the supply of power from an external power source via lead wires 90 connected by solder to the pair of electrode pads 43a and 43b.

[0056] Like the mounting substrate 10, the mounting substrate 40 is a metal substrate made of a metal such as aluminum, has a substantially rectangular planar shape with two pairs of opposing sides, and has a mounting area on its surface where the LED die 14 is mounted. The thickness of the mounting substrate 40 is, for example, 0.7 mm, like the mounting substrate 10. The mounting substrate 40 has a pair of engaging portions 40a and 40b formed at a pair of diagonal corners to engage with fastening members used when fastening the mounting substrate to a heat dissipation member or the like.

[0057] Furthermore, the mounting substrate 40 has a pair of first arrangement portions 46 and 47 formed on a diagonal line connecting a pair of diagonal corners other than the diagonal corners on which the pair of engaging portions 40a and 40b are formed. The pair of first arrangement portions 46 and 47 have the same shape and size, have a substantially rectangular planar shape with rounded inner corners, are formed so as to penetrate from the top surface to the bottom surface of the mounting substrate 40, and are notches extending from one side of the mounting substrate 40 to the opposing side. Lead wires 90 are arranged in the pair of first arrangement portions 46 and 47.

[0058] The length of one side of the rectangular portion of the first arrangement portions 46 and 47 is also referred to as the width of the first arrangement portions 46 and 47. The width of the pair of first arrangement portions 46 and 47 is the separation distance L between the conductor 91 of the lead wire 90 and the mounting board 40 when the lead wire 90 that supplies power from an external power source is arranged. D However, the creepage distance L between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 40 is C is determined to be equal to or greater than the minimum value of

[0059] The circuit board 41 is an insulating substrate made of a glass epoxy material or the like, and has a generally rectangular planar shape with two pairs of opposing sides. The circuit board 41 has an outer edge with the same planar shape as the mounting board 40, is bonded to the surface of the mounting board 40 with an adhesive, and has a circular opening 41a formed in the center. The thickness of the circuit board 41 is, for example, 0.1 mm, similar to that of the circuit board 11. The fact that the mounting board 40 and the circuit board 41 have the same planar shape means that their planar shapes are identical except for the shape of the side surface of the mounting board 40 that is in contact with the outer edges of the first arrangement portions 46 and 47 and the side surface of the circuit board 41 that is in contact with the outer edges of the second arrangement portions 48 and 49.

[0060] A pair of wiring patterns 12a and 12b are formed on the upper surface of the circuit board 41 so as to surround the opening 41a, and a pair of electrode pads 43a and 43b are formed near two diagonally opposite corners. The pair of electrode pads 43a and 43b have the same shape and size and have a substantially rectangular planar shape with rounded inner corners.

[0061] Further, a pair of second arrangement portions 48 and 49 are arranged on the circuit board 41. When the light emitting device 3 is viewed in a plane, each of the pair of second arrangement portions 48 and 49 is arranged near a side of the pair of electrode pads 43a and 43b that contacts one side of each of the pair of wiring patterns 12a and 12b. The pair of second arrangement portions 48 and 49 have the same shape and size and have a rectangular planar shape. When the light emitting device 3 is viewed in a plane, the pair of second arrangement portions 48 and 49 are arranged so that the distance between the outer edges of each of the pair of second arrangement portions 48 and 49 and the outer edges of the pair of first arrangement portions 46 and 47 is approximately the same. The outer edge of the first arrangement portion 46 is the side surface of the first arrangement portion 46 that contacts the mounting substrate 40. Similarly, the outer edge of the first arrangement portion 47 is the side surface of the first arrangement portion 47 that contacts the mounting substrate 40.

[0062] The pair of second arrangement portions 48 and 49 are notches that are formed to penetrate from the upper surface to the lower surface of the circuit board 41 and extend from one side of the circuit board 41 to the opposing side. Lead wires 90 are arranged in the pair of second arrangement portions 48 and 49. When the light emitting device 3 is viewed from above, each of the pair of second arrangement portions 48 and 49 is arranged so as to be sandwiched between inner walls, which are side surfaces of the mounting board 40 that contact the outer edges of the pair of first arrangement portions 46 and 47, respectively, and so that the distances between the outer edges of the pair of second arrangement portions 48 and 49 and the outer edges of the pair of first arrangement portions 46 and 47 are the same. The pair of first arrangement portions 46 and 47 are arranged such that, in a plan view, the outer edges of the pair of second arrangement portions 48 and 49 are positioned between the two ends of one pair of two pairs of two sides of the mounting board 40 and the circuit board 41, and between the two ends of the other pair of two pairs of two sides of the mounting board 40 and the circuit board 41. The length of one side of the pair of second arrangement portions 48 and 49 is determined so that the conductor 91 of the lead wire 90 can pass through it but the covering material 92 cannot. Note that when the pair of first arrangement portions 46 and 47 extend along a diagonal line, the pair of second arrangement portions 48 and 49 and the pair of electrode pads 43a and 43b are also formed to extend along the diagonal line. Furthermore, the inner walls of the circuit board 41, which are the side surfaces of the circuit board 41 that contact the outer edges of the pair of second arrangement portions 48 and 49, are formed of an insulating material. The outer edge of the second arrangement portion 48 is the side surface of the second arrangement portion 48 where the second arrangement portion 48 contacts the circuit board 41. Similarly, the outer edge of the second arrangement portion 49 is the side surface of the second arrangement portion 49 where the second arrangement portion 49 contacts the circuit board 41.

[0063] The distance between the outer edges of the pair of first arrangement portions 46 and 47 and the outer edges of the pair of second arrangement portions 48 and 49 is the creepage distance L between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 40. C The distance between the outer edge of each of the pair of first arrangement portions 46 and 37 and the outer edge of each of the pair of second arrangement portions 48 and 49 may be determined to be equal to or greater than the minimum value of the creepage distance L between the outer edge of the wiring patterns 12 a and 12 b and the mounting substrate 40. CWhen the distance L between the conductor 91 of the lead wire 90 and the mounting board 40 is determined to be equal to or greater than the minimum value of C is the creepage distance L C This allows for more stable setting so that the minimum value is equal to or greater than the specified value.

[0064] FIG. 5 is a diagram showing the relationship between the width of the second arrangement portion 48, the radius of the lead wire 90, and the sinking length of the lead wire 90.

[0065] The sinking length S is expressed by the formula (1) using the width W of the pair of second arrangement portions 48 and 49 and the radius r of the lead wire 90.

[0066]

number

[0067] When the radius of the lead wire 90 is r and the width of the pair of second arrangement portions 48 and 49 is W, the recession length S is obtained as shown in formula (1). Because the recession length S is obtained, the height of the lead wire 90 from the upper surface of the circuit board 41 becomes smaller than the width of the lead wire 90. Because the height of the lead wire 90 from the upper surface of the circuit board 41 becomes smaller, the amount of light reflected by the lead wire 90 is reduced, and the decrease in light-emitting efficiency is suppressed.

[0068] The method for manufacturing the light emitting device 3 is the same as the method for manufacturing the light emitting device 1, and therefore a detailed description thereof will be omitted here.

[0069] (Actions and Effects of the Light Emitting Device According to the Third Embodiment) In the light emitting device 3, the first arrangement portions 46 and 47 and the second arrangement portions 48 and 49 are notches extending toward the opposite sides, so that the lead wires 90 can be arranged in the first arrangement portions 46 and 47 and the second arrangement portions 48 and 49 from the sides of the light emitting device 2. In the light emitting device 3, the lead wires 90 can be arranged in the first arrangement portions 46 and 47 and the second arrangement portions 48 and 49 from the sides of the light emitting device 3, so that the connection process for connecting the lead wires 90 to the light emitting device 3 is easier than the connection process for the light emitting device 1.

[0070] (Configuration and Function of Light-Emitting Device According to Fourth Embodiment) FIG. 6(a) is a plan view of a light-emitting device according to a fourth embodiment, and FIG. 6(b) is a plan view of a mounting substrate included in the light-emitting device shown in FIG. 6(a). FIG. 7(a) is a plan view of the light-emitting device shown in FIG. 6(a) excluding the pair of conductive plates, and FIG. 7(b) is a plan view of the conductive plates shown in FIG. 7(a). FIG. 7(c) is a side view of the conductive plates shown in FIG. 7(a), and FIG. 7(d) is a partial side view of the light-emitting device to which a lead wire 90 is connected, as viewed from the direction indicated by arrow A in FIG. 6(a). In the light-emitting device 4, the first and second arrangement portions in which the lead wire 90 is arranged are formed as notches extending toward the opposing sides, instead of the first arrangement portions 21 and 22 and the second arrangement portions 23 and 24 being through-holes.

[0071] The light emitting device 4 differs from the light emitting device 1 in that it includes a mounting substrate 50, a circuit board 51, and a pair of electrode pads 53a and 53b, and 53c and 53d, instead of the mounting substrate 10, the circuit board 11, and the pair of electrode pads 13a and 13b. The light emitting device 4 also differs from the light emitting device 1 in that it includes a pair of conductive plates 54a and 54b. The configurations and functions of the components of the light emitting device 4 other than the mounting substrate 50, the circuit board 51, the pair of electrode pads 53a and 53b, and 53c and 53d, and the pair of conductive plates 54a and 54b are identical to the configurations and functions of the components of the light emitting device 1 with the same reference numerals, and therefore detailed description thereof will be omitted here. The light emitting device 4 emits white light in response to power supplied from an external power source via lead wires 90 soldered to the pair of conductive plates 54a and 54b.

[0072] Like the mounting substrate 10, the mounting substrate 50 is a metal substrate made of a metal such as aluminum, has a substantially rectangular planar shape with two pairs of opposing sides, and has a mounting area on its surface where the LED die 14 is mounted. The thickness of the mounting substrate 50 is, for example, 0.7 mm, like the mounting substrate 10. The mounting substrate 50 has a pair of engaging portions 50a and 50b formed at a pair of diagonal corners to engage with fastening members used when fastening the mounting substrate to a heat dissipation member or the like.

[0073] Furthermore, the mounting substrate 50 has a pair of first arrangement portions 56 and 57 formed on a diagonal line connecting a pair of diagonal corners other than the diagonal corners on which the pair of engaging portions 50a and 50b are formed. The pair of first arrangement portions 56 and 57 have the same shape and size, are formed to penetrate from the upper surface to the lower surface of the mounting substrate 50, have a planar shape connecting a circular portion and a rectangular portion extending outward from the circular portion toward the adjacent side, and are notches extending toward the side of the mounting substrate 50. Lead wires 90 are arranged in the pair of first arrangement portions 56 and 57.

[0074] The diameter of the circular portions of the pair of first placement portions 56 and 57 is set to be equal to the distance L between the conductor 91 of the lead wire 90 and the mounting board 50 when the lead wire 90 for supplying power from an external power source is placed. D However, the creepage distance L between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 50 is C The pair of first arrangement portions 56 and 57 may be through holes instead of notches.

[0075] The circuit board 51 is an insulating board made of a glass epoxy material or the like, has an outer edge with the same planar shape as the mounting board 50, is bonded to the surface of the mounting board 50 with an adhesive, and has a circular opening 51a formed in the center. The thickness of the circuit board 51 is, for example, 0.1 mm, similar to that of the circuit board 11. The mounting board 50 and the circuit board 51 having the same planar shape means that their planar shapes are the same except for the shape of the side surface of the mounting board 50 that the outer edges of the first arrangement portions 56 and 57 contact and the side surface of the circuit board 51 that the outer edges of the second arrangement portions 58 and 59 contact.

[0076] A pair of wiring patterns 12a and 12b is formed on the upper surface of the circuit board 51 so as to surround the opening 51a, and a pair of electrode pads 53a and 53b, and 53c and 53d, are formed near two diagonally opposite corners, respectively. The electrode pads 53a and 53b have a substantially rectangular shape with rounded corners in plan view and are formed on the wiring pattern 12a so as to face each other across a first arrangement portion 56. The electrode pads 53c and 53d have a substantially rectangular shape with rounded corners in plan view and are formed on the wiring pattern 12b so as to face each other across a first arrangement portion 57. The areas where the pairs of electrode pads 53a and 53b and 53c and 53d are arranged are arranged so as to overlap the mounting substrate 50 when the light emitting device 4 is viewed from above.

[0077] Furthermore, a pair of second arrangement portions 58 and 59 are arranged on the circuit board 51. When the light emitting device 4 is viewed from above, the pair of second arrangement portions 58 and 59 are arranged between the electrode pads 53a and 53b and between the electrode pads 53c and 53d, respectively. The pair of second arrangement portions 58 and 59 have the same shape and size, and each have a semicircular portion and a rectangular portion with one side having the same length as the diameter of the semicircular portion.

[0078] The pair of second arrangement portions 58 and 59 are formed to penetrate from the upper surface to the lower surface of the circuit board 51, are arranged so that the center of each semicircular portion of the pair of second arrangement portions 58 and 59 coincides with the center of each circular portion of the pair of first arrangement portions 56 and 57, have a planar shape connecting a semicircular portion and a rectangular portion extending from the semicircular portion toward the side of the circuit board 51, and are notches formed near a diagonal of the mounting board 50. Lead wires 90 are arranged in the pair of second arrangement portions 58 and 59. The pair of second arrangement portions 58 and 59 are arranged so as to be sandwiched between the pair of first arrangement portions 56 and 57 when the light emitting device 4 is viewed from above, and are arranged so that the center of each semicircular portion of the pair of second arrangement portions 58 and 59 coincides with the center of each circular portion of the pair of first arrangement portions 56 and 57. The pair of first arrangement portions 56 and 57 are arranged such that, in a plan view, the outer edges of the pair of first arrangement portions 56 and 57 are located between the outer edges of the pair of second arrangement portions 58 and 59 and one of the two pairs of two sides of the mounting substrate 50 and the circuit board 51, and between the outer edges of the pair of second arrangement portions 58 and 59 and one of the two pairs of two sides of the mounting substrate 50 and the circuit board 51. The diameters of the semicircular portions of the pair of second arrangement portions 58 and 59 are determined so that the covering material 92 of the lead wire 90 can pass through them. Note that when the pair of first arrangement portions 56 and 57 are through holes, the pair of second arrangement portions 58 and 59 are formed as through holes rather than notches. The outer edge of the second arrangement portion 58 is the side surface of the second arrangement portion 58 that contacts the circuit board 51. Similarly, the outer edge of the second arrangement portion 59 is the side surface of the second arrangement portion 59 where the second arrangement portion 59 contacts the circuit board 51.

[0079] The distance between the outer edge of each of the circular portions of the pair of first arrangement portions 56 and 57 and the outer edge of each of the semicircular portions of the pair of second arrangement portions 58 and 59 is the creepage distance L between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 50. C The distance between the outer edge of each circular portion of the pair of first arrangement portions 56 and 57 and the outer edge of each semicircular portion of the pair of second arrangement portions 58 and 59 may be determined to be equal to or greater than the minimum value of the creepage distance L between the wiring patterns 12 a and 12 b and the outer edge of the mounting substrate 50. CWhen the distance L between the conductor 91 of the lead wire 90 and the mounting board 50 is determined to be equal to or greater than the minimum value of D is the creepage distance L C The outer edge of the first arrangement portion 56 is the side surface of the first arrangement portion 56 where the first arrangement portion 56 comes into contact with the mounting board 50. Similarly, the outer edge of the first arrangement portion 57 is the side surface of the first arrangement portion 57 where the first arrangement portion 57 comes into contact with the mounting board 50.

[0080] In a plan view, the outer edges of the rectangular portions of the pair of first arrangement portions 56 and 57 and the outer edges of the rectangular portions of the pair of second arrangement portions 58 and 59 may partially coincide with each other.

[0081] The conductive plate 54a is formed of a rigid conductive material such as an alloy steel such as stainless steel, a copper alloy such as phosphor bronze, or an iron-nickel alloy such as 42 alloy, and has a pair of connecting portions 54c and 54d, a pair of leg portions 54e and 54f, and a flat portion 54g. The conductive plate 54a has a circular conductor through-hole 54h formed in the center of the flat portion 54g. The pair of connecting portions 54c and 54d have a substantially rectangular planar shape. The pair of connecting portions 54c and 54d are arranged to straddle the first arrangement portion 56 and the second arrangement portion 58, respectively, and are connected to the electrode pads 53a and 53b. The pair of leg portions 54e and 54f connect each end of the flat portion 54g to the pair of connecting portions 54c and 54d, respectively. The flat portion 54g has a substantially rectangular planar shape and has a conductor through-hole 54h formed in its center. The conductor through hole 54h is a through hole that penetrates the front and rear surfaces of the flat plate portion 54g, and has a diameter that allows the conductor 91 of the lead wire 90 to pass through but does not allow the coating material 92 to pass through.

[0082] The conductive plate 54a is formed by subjecting a conductive member to metal processing such as pressing, casting, and cutting. The upper surface of the flat plate portion 54g may be plated with tin, gold, silver, solder, or the like to secure the lead wire 90. The solder plated on the upper surface of the flat plate portion 54g is, for example, a Sn-Ag-Cu-based solder with a melting temperature of approximately 215°C to 220°C. The conductive plate 54b has the same configuration and function as the conductive plate 54a, and therefore detailed description of the conductive plate 54b will be omitted.

[0083] The conductive plate 54a may have a notch formed therein instead of the conductor through-hole 54h. The conductive plate 54a has a pair of legs 54e and 54f, but may be a flat plate omitting the pair of legs 54e and 54f.

[0084] The conductive plate 54a is electrically connected to the electrode pads 53a and 53b by electrically connecting the pair of connecting portions 54c and 54d to the electrode pads 53a and 53b via a conductive adhesive 55 such as solder. The conductive adhesive 55 is a conductive material having a melting temperature higher than that of the solder plated on the upper surface of the flat plate portion 54g, and an example of the conductive adhesive is a Sn-Ag-Cu solder having a melting temperature of approximately 215°C to 220°C. When the conductor 91 of the lead wire 90 is electrically connected to the flat plate portion 54g via the conductor through-hole 54h, the conductor 91 is electrically connected to the electrode pads 53a and 53b via the conductive plate 54a and the conductive adhesive 55.

[0085] The method for manufacturing the light emitting device 4 is the same as the method for manufacturing the light emitting device 1, and therefore a detailed description thereof will be omitted here.

[0086] (Functions and Effects of the Light Emitting Device According to the Fourth Embodiment) In the light emitting device 4, the lead wire 90 is supported by a pair of conductive plates 54a and 54b formed of a rigid conductive material that is joined on the mounting substrate 50, so the lead wire 90 can be supported more firmly than in the light emitting devices 1 to 3, which are supported by a thinner circuit board 51.

[0087] (Configuration and Function of Light-Emitting Device According to Fifth Embodiment) Fig. 8 is a plan view of a light emitting device according to a fifth embodiment, and Fig. 9 is a plan view seen through the dam material 17 and the sealing material 18 in the light emitting device shown in Fig. 8. In the light emitting device 5, the first and second arrangement portions in which the lead wires 90 are arranged are formed as through holes formed near the centers of opposing sides, instead of the first arrangement portions 21 and 22 and the second arrangement portions 23 and 24, which are through holes formed near opposing corners.

[0088] The light emitting device 5 differs from the light emitting device 1 in that it has a mounting substrate 60, a circuit board 61, a pair of wiring patterns 62a and 62b, and a pair of electrode pads 63a and 63b instead of the mounting substrate 10, the circuit board 11, the pair of wiring patterns 12a and 12b, and the pair of electrode pads 13a and 13b. The configurations and functions of the components of the light emitting device 5 other than the mounting substrate 60, the circuit board 61, the pair of wiring patterns 62a and 62b, and the pair of electrode pads 63a and 63b are the same as the configurations and functions of the components of the light emitting device 1 with the same reference numerals, and therefore detailed description thereof will be omitted here. The light emitting device 5 emits white light in response to power supplied from an external power source via lead wires 90 connected by solder to the pair of electrode pads 63a and 63b.

[0089] Like the mounting substrate 10, the mounting substrate 60 is a metal substrate made of a metal such as aluminum. It has a generally rectangular planar shape with two pairs of opposing sides and a mounting area on its surface where the LED dies 14 are mounted. 48 LED dies 14 are mounted in the mounting area. The 48 LED dies 14 are connected in series in groups of 12, and are connected in parallel across four rows. The thickness of the mounting substrate 60 is, for example, 0.7 mm, like the mounting substrate 10. The mounting substrate 60 has a pair of engaging portions 60a and 60b formed near a pair of diagonal corners, which are through-holes into which fastening members are engaged when fastening the mounting substrate to a heat dissipation member or the like.

[0090] Furthermore, a pair of first arrangement portions 66 and 67 are formed in the center of a pair of opposing sides of the mounting substrate 60. The pair of first arrangement portions 66 and 67 have the same shape and size, are formed to penetrate from the top surface to the bottom surface of the mounting substrate 60, have a substantially rectangular planar shape, and are notches extending toward the opposing sides. Lead wires 90 are arranged in the pair of first arrangement portions 66 and 67.

[0091] The width of the pair of first arrangement portions 66 and 67 is a distance L between the conductor 91 of the lead wire 90 and the mounting substrate 60, i.e., the inner wall, which is the side surface of the mounting substrate 60 that contacts the outer edges of the pair of first arrangement portions 66 and 67, when the lead wire 90 is arranged in the pair of first arrangement portions 66 and 67. D However, the creepage distance L between the wiring patterns 62a and 62b and the outer edge of the mounting substrate 60 is C The outer edge of the first arrangement portion 66 is the side surface of the first arrangement portion 66 where the first arrangement portion 66 comes into contact with the mounting substrate 60. Similarly, the outer edge of the first arrangement portion 67 is the side surface of the first arrangement portion 67 where the first arrangement portion 67 comes into contact with the mounting substrate 60.

[0092] The circuit board 61 is an insulating substrate made of a glass epoxy material or the like, and has a generally rectangular planar shape with two pairs of opposing sides. The circuit board 61 has an outer edge with the same planar shape as the mounting board 60, is bonded to the surface of the mounting board 60 with an adhesive, and has a circular opening 61a formed in the center. The thickness of the circuit board 61 is, for example, 0.1 mm, similar to that of the circuit board 11. The fact that the mounting board 60 and the circuit board 61 have the same planar shape means that their planar shapes are identical except for the shape of the side surface of the mounting board 60 that the outer edges of the first arrangement portions 66 and 67 contact and the side surface of the circuit board 61 that the outer edges of the second arrangement portions 68 and 69 contact.

[0093] A pair of wiring patterns 62a and 62b is formed on the upper surface of the circuit board 61 so as to surround the opening 61a, and a pair of electrode pads 63a and 63b is formed on each of the pair of wiring patterns 62a and 62b near the center of one of two pairs of opposing sides. The thickness of the pair of wiring patterns 62a and 62b is, for example, 0.035 mm, similar to that of the circuit board 11. Each of the pair of electrode pads 63a and 63b has a pair of approximately rectangular planar shapes. In addition, a pair of check pads 62c and 62d is formed on each of the pair of wiring patterns 62a and 62b on a diagonal line connecting the other pair of diagonal corners on which the pair of engagement portions 60a and 60b are formed.

[0094] Further, a pair of second arrangement portions 68 and 69 are arranged on the circuit board 61. The pair of second arrangement portions 68 and 69 have the same shape and size, have a circular planar shape, and are arranged so that the centers of the pair of electrode pads 63a and 63b and the centers of the pair of second arrangement portions 68 and 69 coincide with each other. The pair of first arrangement portions 66 and 67 are arranged so that the outer edges of the pair of first arrangement portions 66 and 67 are located between the outer edges of the pair of second arrangement portions 68 and 69 and two pairs of two sides of the mounting board 60 and the circuit board 61 in a plan view. The outer edge of the second arrangement portion 68 is the side surface of the second arrangement portion 68 where the second arrangement portion 68 contacts the circuit board 61. Similarly, the outer edge of the second arrangement portion 69 is the side surface of the second arrangement portion 69 where the second arrangement portion 69 contacts the circuit board 61.

[0095] The pair of second arrangement portions 68 and 69 are through holes formed to penetrate from the upper surface to the lower surface of the circuit board 61, and into which the lead wire 90 is inserted. The pair of second arrangement portions 68 and 69 are arranged so as to be surrounded by the pair of first arrangement portions 66 and 67 when the light emitting device 5 is viewed in plan. The diameter of the pair of second arrangement portions 68 and 69 is determined so that the conductor 91 of the lead wire 90 can pass through them but the covering material 92 cannot.

[0096] The method for manufacturing the light emitting device 5 is the same as the method for manufacturing the light emitting device 1, and therefore a detailed description thereof will be omitted here.

[0097] (Application example of the light emitting device according to the embodiment) Fig. 10 is a diagram showing a lighting device as an example of an application of the light emitting device according to the embodiment, in which Fig. 10(a) is a plan view of the lighting device, Fig. 10(b) is a cross-sectional view taken along line AA shown in Fig. 10(a), and Fig. 10(c) is an enlarged cross-sectional view of the area surrounded by dashed line B shown in Fig. 10(b).

[0098] The lighting device 100 includes a light emitting device 1, a heat dissipation member 101, a pair of lead wires 90a and 90b, a pair of fastening members 102a and 102b, a pair of joining members 103a and 103b, and a thermal joining member 104, and emits white light in response to application of a voltage to the pair of lead wires 90a and 90b. The lighting device 100 includes the light emitting device 1, but may include light emitting devices 2 to 5 instead of the light emitting device 1.

[0099] The heat dissipation member 101 is made of a metal with high thermal conductivity, such as aluminum, and is disposed on the rear surface of the light emitting device 1 via a thermal bonding member 104. The heat dissipation member 101 has a pair of through holes 101a and 101b formed therein, through which the pair of lead wires 90a and 90b are disposed. The pair of through holes 101a and 101b have diameters longer than the diameters of the pair of lead wires 90a and 90b, and are formed between the upper and lower surfaces of the heat dissipation member 101.

[0100] The pair of through holes 101a and 101b are formed at their upper ends with hemispherical separating portions 101c and 101d, respectively. The shape of the separating portions 101c and 101d is determined by the creepage distance L between the conductors of the pair of lead wires 90a and 90b and the heat dissipation member 101. D The creepage distance L between the wiring patterns 12a and 12b and the outer edge of the mounting substrate 10 is C The shape of the separating portions 101c and 101d is hemispherical, but the shape of the separating portions of the heat dissipation member may be a shape other than hemispherical, such as a truncated cone.

[0101] The pair of lead wires 90a and 90b has a conductor such as tin-plated annealed copper wire and a covering material formed of an insulator such as flame-retardant cross-linked polyolefin. The conductor of the pair of lead wires 90a and 90b may be a solid wire or a twisted wire.

[0102] The pair of fastening members 102a and 102b are threaded members such as screws, and fasten the light emitting device 1 and the heat dissipation member 101 together to fix the heat dissipation member 101 to the light emitting device 1. The heads of the pair of fastening members 102a and 102b cover the pair of engagement portions 10a and 10b of the light emitting device 1, and the threaded portions are threaded into the heat dissipation member 101.

[0103] The pair of joining members 103a and 103b are solder and electrically connect the conductors of the pair of lead wires 90a and 90b to the pair of electrode pads of the light emitting device 1. The joining member 103a electrically connects the conductor of the lead wire 90a to the electrode pad 13a of the light emitting device 1, and the joining member 103b electrically connects the conductor of the lead wire 90b to the electrode pad 13b of the light emitting device 1. Power is supplied to the light emitting device 1 from an external power source (not shown) via the pair of lead wires 90a and 90b.

[0104] The thermal bonding member 104 is a viscous fluid material with high thermal conductivity. The thermal bonding member 104 may be in a paste form or a sheet form. The thermal bonding member 104 is disposed between the lower surface of the mounting substrate 10 and the upper surface of the heat dissipation member 101.

[0105] The pair of first arrangement portions 21 and 22 may be filled with an insulating synthetic resin so as to cover the pair of lead wires 90a and 90b.

[0106] The filling member 105 is an insulating synthetic resin such as silicone, and is filled so as to cover the pair of lead wires 90a and 90b in the pair of first arrangement portions 21 and 22. The filling member 105 may fill the space between the light emitting device 1 and the heat dissipation member 101 and the entire pair of through holes 101a and 101b, or may fill the space between the light emitting device 1 and the heat dissipation member 101 and part of the pair of through holes 101a and 101b.

[0107] The lighting device 100 includes a heat dissipation member 101 made of a metal with high thermal conductivity, allowing the heat generated in the light-emitting device 1 to be efficiently dissipated to the outside. Furthermore, the lighting device 100 includes a pair of through-holes in which the pair of lead wires 90a and 90b can be arranged. This allows the pair of lead wires 90a and 90b to be efficiently extended to the outside without the need to route them outside the heat dissipation member 101. Furthermore, the lighting device 100 includes a filling member 105 that covers the pair of lead wires 90a and 90b in the pair of first arrangement portions 21 and 22, thereby shortening the creepage distance and increasing the dielectric strength voltage. Furthermore, the filling member 105 is filled between the light-emitting device 1 and the heat dissipation member 101 and in the pair of through-holes 101a and 101b, allowing the pair of lead wires 90a and 90b to be stably installed. [Explanation of symbols]

[0108] 1~5 Light-emitting device 10, 30, 40, 50 Mounting board 11, 31, 41, 51 Circuit board 12a, 12b, 62a, 62b wiring patterns 13a, 13b, 33a, 33b, 43a, 43b, 53a, 53b, 63a, 63b, electrode pads 14 LED dies (light-emitting elements) 90 Lead wire (conductive material) 91 Conductor

Claims

1. a mounting substrate having a pair of first placement portions formed by through holes or notches in which conductive members for supplying power can be placed; a circuit board disposed on the mounting board, the circuit board having a pair of second arrangement portions formed by through holes or notches in which the conductive members disposed in the pair of first arrangement portions can be disposed, and a pair of wiring patterns connectable to the conductive members disposed in the pair of second arrangement portions; a light-emitting element connected to the pair of wiring patterns and mounted on the mounting substrate, The light emitting device, wherein the pair of first arrangement portions are arranged so as to surround at least a portion of the periphery of each of the pair of second arrangement portions in a plan view.

2. the mounting board and the circuit board have two pairs of sides arranged opposite to each other, The light-emitting device of claim 1, wherein the pair of first arrangement portions are arranged so that, in a planar view, at least the outer edges of the pair of first arrangement portions are located between the outer edges of the pair of second arrangement portions and two sides of one of the two pairs of sides, and between the outer edges of the pair of second arrangement portions and one of the two sides of the other pair of sides.

3. 2. The light emitting device according to claim 1, wherein the separation distance between the outer edge of the first arrangement portion and the outer edge of the second arrangement portion is equal to or greater than the minimum creepage distance between the pair of wiring patterns and the outer edge of the mounting substrate.

4. The light emitting device according to claim 1 , wherein the pair of first arrangement portions are arranged on diagonal corners of the mounting substrate.

5. The light emitting device according to claim 1 , wherein the pair of first arrangement portions are arranged near a center of one of a pair of opposing sides of the mounting substrate.

6. 6. The light emitting device according to claim 1, wherein the circuit board further comprises a pair of electrode pads formed on each of the pair of wiring patterns.

7. The light emitting device according to claim 6 , wherein the pair of first arrangement portions and the pair of second arrangement portions are through holes formed so as to penetrate through a region surrounded by the pair of electrode pads.

8. The light emitting device according to claim 6 , wherein the pair of first arrangement portions and the pair of second arrangement portions are notches formed so as to penetrate through a region sandwiched between the pair of electrode pads.

9. The light emitting device according to claim 6 , wherein the pair of first arrangement portions and the pair of second arrangement portions are notches formed in regions adjacent to the pair of electrode pads, respectively.

10. The light emitting device according to claim 6 , further comprising a conductive plate arranged to straddle the pair of first arrangement portions and the pair of second arrangement portions.

11. a pair of conductive members connectable to an external power source; a light-emitting device connected to the pair of conductive members and configured to emit light in response to power being supplied via the pair of conductive members; a heat dissipation member fixed to the light emitting device and configured to dissipate heat generated by the light emitting device, The light emitting device comprises: a mounting substrate having a pair of first placement portions formed by through holes or notches in which the pair of conductive members can be placed, respectively; a circuit board having a pair of second arrangement portions formed by through holes or notches in which the pair of conductive members can be arranged, and a pair of wiring patterns connectable to the conductive members arranged in the pair of second arrangement portions; a light-emitting element connected to the pair of wiring patterns and mounted on the mounting substrate, The lighting device, wherein the pair of first arrangement portions are arranged so as to surround at least a portion of the periphery of each of the pair of second arrangement portions in a plan view.

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