JP2007294867A - Light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting device which is hard to reduce light extraction efficiency of an light emitting element, even if a resin substrate superior in thermal conductivity is used. <P>SOLUTION: The light emitting device includes a resin substrate 14 having thermal conductivity of 1.0-9.0 [W/m K], a white insulating layer 15 formed on the resin substrate, a circuit pattern layer 16 formed on the insulating layer, and a light emitting element 13 which is formed on the insulating layer and is electrically connected with the circuit pattern layer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

  Conventionally, for example, as an example of a light emitting diode device, a surface mount type device in which a synthetic resin is filled in a case (cup) in which a light emitting diode chip is disposed and the light emitting diode chip is sealed in the case is known. (See Patent Document 1).

  Also, among this type of light emitting diode device, there is known a case in which the case is formed of a synthetic resin such as PPA (polyphthalamide), but this synthetic resin has a thermal conductivity of, for example, about 0.3. Since it is about [W / m · K] and the heat dissipation is low, there is a problem that the light emission efficiency of the light-emitting diode chip decreases as the temperature rises.

In the second prior art light emitting diode device, in order to suppress the temperature rise, a heat dissipation hole is formed in the ceramic substrate, and an auxiliary ceramic sheet is provided on the inner surface side of the heat dissipation hole. A device in which a light emitting diode chip is mounted thereon to improve heat dissipation of the light emitting diode chip is known (see, for example, Patent Document 2).
JP 2002-43625 A JP 2002-353515 A

  When using a resin with excellent heat dissipation, the heat of the light-emitting diode element can be efficiently released and the light emission efficiency of the light-emitting diode element can be prevented from decreasing, but the light reflectance is relatively lowered because this type of resin is not white. However, since the light traveling from the light emitting diode element toward the substrate is easily absorbed, there is a problem that the efficiency of extracting light from the light emitting diode element is lowered.

  An object of the present invention is to provide a light-emitting device in which the light extraction efficiency of a light-emitting element is hardly lowered even when a resin substrate having excellent thermal conductivity is used.

  The invention according to claim 1 is a resin substrate having a thermal conductivity of 1.0 to 9.0 [W / m · K]; a white insulating layer provided on the resin substrate; and provided on the insulating layer And a light emitting element disposed on the insulating layer and electrically connected to the circuit pattern layer.

  The resin constituting the resin substrate contains 50 to 90% by mass of an inorganic filler in a synthetic resin base material such as polyamide or PPA (polyphthalamide), so that the thermal conductivity is 1.0 to 9.0 [W / M · K]. You may form the recessed part which arrange | positions a light emitting element with this resin substrate. In addition, since the resin substrate has electrical insulation, it is not necessary to form an electrical insulation layer between the resin pattern and the circuit pattern layer. However, in the present invention, a white electrical insulation layer is provided to improve the reflectance. Moreover, since this resin is a highly heat-dissipating synthetic resin having a thermal conductivity of 1.0 to 9.0 [W / m · K], heat dissipation can be improved. For this reason, it can suppress that luminous efficiency falls because of a temperature rise of a light emitting element. The thermal conductivity of the resin substrate may be 9.0 [W / m · K] or more. In this case, since the content of the inorganic filler contained in the synthetic resin base material increases, the fluidity of the synthetic resin base material decreases and the processability decreases, but the heat dissipation can be further improved. A white resin material can be used for the white insulating layer.

  The invention according to claim 2 is a resin substrate having a thermal conductivity of 1.0 to 9.0 [W / m · K]; a white insulating layer provided on the resin substrate; and provided on the insulating layer A circuit pattern layer; a receiving portion provided on the insulating layer and the circuit pattern layer of the substrate and having an opening formed on the insulating layer and the circuit pattern layer of the substrate corresponding to the light emitting element arrangement position; A reflector configured such that the circuit pattern layer is positioned on the insulating layer in a central region within the reflector housing portion and electrically connected to the circuit pattern layer located in the peripheral region within the housing portion And a connected light emitting element.

  According to a third aspect of the present invention, in the light emitting device according to the second aspect, the ratio of the surface area of the insulating layer facing the housing portion is greater than the ratio of the surface area of the circuit pattern layer.

  According to a fourth aspect of the present invention, in the light emitting device according to any one of the first to third aspects, the reflectance of the surface of the insulating layer is 85% or more in the wavelength range of 400 to 740 nm. When the reflectance of the surface of the insulating layer is less than 85% in the wavelength range of 400 to 740 nm, the efficiency of reflecting light from the light emitting element toward the substrate by the insulating layer is low, and the light extraction efficiency of the light emitting element is sufficiently improved. I can't get it. In addition, the said reflectance is a total light reflectance, for example.

  According to a fifth aspect of the present invention, in the light emitting device according to any one of the first to fourth aspects, the resin substrate contains 50 to 90% by mass of an inorganic filler in a synthetic resin base material.

  The inorganic filler is made of at least one of alumina, magnesia, beryllia, silica, boron nitride, aluminum carbide, silicon carbide, boron carbide, titanium carbide, silicon nitride, diamond, iron, aluminum, copper, or a combination of two or more thereof. Become. By adjusting the content of the inorganic filler, the heat dissipation of the resin substrate can be easily adjusted to a suitable value.

  According to a sixth aspect of the present invention, in the light emitting device according to the fifth aspect, the inorganic filler has a substantially spherical shape with a diameter of 100 μm or less. Since the inorganic filler has a spherical shape with a diameter of 100 μm, the injection efficiency at the time of injection molding of this highly heat-dissipating synthetic resin can be improved, and fine filling becomes possible.

  According to a seventh aspect of the present invention, in the light emitting device according to any one of the first to sixth aspects, the thickness of the insulating layer is in the range of 30 μm to 90 μm. When the thickness of the insulating layer is less than 30 μm, light is transmitted through the insulating layer, the reflectance is lowered, and the insulating performance is lowered. On the other hand, when the thickness of the insulating layer is greater than 90 μm, the thermal resistance of the insulating layer is increased, heat dissipation is reduced, and the life of the light emitting element is shortened.

  According to the light emitting device of claim 1, the circuit pattern layer is provided by providing the white insulating layer on the resin substrate excellent in heat dissipation, the light emitting element is provided on the insulating layer, and then the light is emitted to the circuit pattern layer. Since the elements are electrically connected, the heat dissipation is excellent, and the light from the light emitting element toward the substrate can be efficiently reflected by the white insulating layer, so that the light extraction efficiency of the light emitting element can be improved.

  According to the light emitting device of claim 2, a circuit pattern layer is provided by providing a white insulating layer on a resin substrate excellent in heat dissipation, and the center in the accommodating portion of the reflector provided on the insulating layer and the circuit pattern. Since the light emitting element is disposed on the insulating layer in the region and is electrically connected to the circuit pattern layer located in the peripheral region in the housing portion by wire bonding, it has excellent heat dissipation, and light directed from the light emitting element to the substrate side Light can be efficiently reflected by the white insulating layer, and the light extraction efficiency of the light emitting element can be improved.

  According to the light emitting device according to claim 3, in addition to the effect of the light emitting device according to claim 2, the ratio of the surface area of the insulating layer facing the housing portion is larger than the ratio of the surface area of the circuit pattern layer. Therefore, the light traveling from the light emitting element toward the substrate can be efficiently reflected by the white insulating layer, and the light extraction efficiency of the light emitting element can be improved.

  According to the light emitting device according to claim 4, in addition to the effect of the light emitting device according to any one of claims 1 to 3, the reflectance of the surface of the insulating layer is 85% or more in the wavelength range of 400 to 740 nm. Light from the light emitting element toward the substrate can be efficiently reflected by the white insulating layer, and the light extraction efficiency of the light emitting element can be improved.

  According to the light emitting device of claim 5, the resin substrate has a content of the inorganic filler contained in the synthetic resin base material of 50% by mass, and the synthetic resin excellent in workability is 50% by mass. And heat dissipation can be improved, maintaining processability. In addition, since the content of the inorganic filler is 90% or less, the heat dissipation can be further improved, and since the content of the synthetic resin excellent in processability is 10% by mass, the processability is also maintained. be able to.

  According to the light emitting device of the sixth aspect, since the inorganic filler has a spherical shape with a diameter of 100 μm or less, the injection property of the high heat radiation synthetic resin at the time of injection molding can be improved, and the mold can be closely packed. It becomes.

  According to the light emitting device according to claim 7, in addition to the effect of the light emitting device according to any one of claims 1 to 6, in order to make the thickness of the insulating layer in the range of 30 μm to 90 μm, while ensuring the reflectance, The heat dissipation can be improved.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 is an enlarged cross-sectional view of a part of the light emitting device, FIG. 2 is an enlarged front view of the light emitting device omitted, FIG. 3 is a front view of the light emitting device, FIG. 4 is a cross sectional view of the light emitting device, and FIG. It is a graph which shows the total light reflectance of the white resin material used for an apparatus. In the figure, a light emitting device 11 includes a light emitting module 12, and the light emitting module 12 is detachably attached to a light emitting device main body (not shown) such as a fixture main body of a lighting fixture.

In the light emitting module 12, light emitting diode elements (light emitting diode chips) 13 which are chip-like solid light emitting elements as a plurality of light emitting elements are arranged in a matrix. The light emitting diode element 13 is made of, for example, a gallium nitride (GaN) based semiconductor that emits blue light having an emission peak of 450 to 460 nm.

  The light emitting module 12 includes, for example, 50 to 90% by mass of an inorganic filler in a synthetic resin base material such as polyamide or PPA (polyphthalamide), so that the thermal conductivity is 1.0 to 9.0 [W / m · K], a white insulating layer 15 formed on one surface of the substrate 14, a circuit pattern layer 16 formed on the insulating layer 15, and on the insulating layer 15 and the circuit pattern layer 16 Has a reflector 17 formed integrally therewith.

  The insulating layer 15 is formed so as to cover the entire surface of the substrate 14 with an insulating white resin material. In the wavelength range of 400 to 740 nm, the reflectance of the surface of the insulating layer 15 is preferably 85% or more. If the reflectance is smaller than 85%, the efficiency of reflecting the light from the light emitting diode element 13 toward the substrate 14 on the insulating layer 15 is high. Therefore, the light extraction efficiency of the light emitting diode element 13 cannot be sufficiently improved. Here, the graph which shows the total light reflectance of the white resin material used for a light-emitting device is shown in FIG. The horizontal axis of the graph is the wavelength (nm), the vertical axis is the total light reflectance (%), the solid line is the total light reflectance of the white resin material, and the dotted line is the total light reflectance of silver as a comparative example. Yes. In the case of silver, it has a total light reflectance of 85% or more in the entire wavelength range of 400 to 740 nm. On the other hand, in the case of a white resin material, the total light reflectance is 35% at a wavelength of 400 nm, and the wavelength of 480 to 740 nm is 85% or more. However, since the average total light reflectance is 85% or more in the entire wavelength range of 400 to 740 nm, the light extraction efficiency can be sufficiently improved.

  In addition, since the insulating layer 15 is provided on almost the entire surface of the substrate 14, productivity is improved as compared with the case where the insulating layer 15 is accurately provided only at the required position on the substrate 14, that is, the position of the accommodating portion 19 of the reflector 17. it can. The thickness of the insulating layer 15 is preferably in the range of 30 μm to 90 μm, and heat dissipation can be improved while ensuring the reflectance. Here, the thickness of the insulating layer 15 will be described taking the thicknesses of 30 μm, 90 μm, and 120 μm as examples. FIG. 6 shows the reflectance at a wavelength of 460 nm, the reflectance at a wavelength of 550 nm, and the thermal resistance (° C./W) when the insulating layer 15 has a thickness of 30 μm, 90 μm, and 120 μm. The thinner the insulating layer 15, the lower the reflectivity. On the other hand, the thicker the insulating layer 15, the higher the thermal resistance. The light emitting diode element 13 has a life of 40,000 hours when the junction temperature is used at 100 ° C. Therefore, to increase the life of the light emitting diode element 13, the junction temperature should be kept below 100 ° C. It is preferable to do this.

  When the W number per chip of the light emitting diode element 13 is 0.06 W, the temperature rise when the power is turned on by the application of 0.06 W electric power is thin as shown in FIG. Since the thermal resistance is lower, the temperature rise is lower. On the other hand, the thicker the insulating layer 15, the higher the thermal resistance. For example, in a sealed luminaire using a light emitting diode element capable of obtaining a light flux of 5000 lm as a light source, the ambient temperature in the fixture is 60 ° C to 70 ° C. Since the value obtained by adding the above-mentioned temperature rise to this temperature is the junction temperature, the junction temperature exceeds 100 ° C. when the thickness of the insulating layer 15 is 120 μm. Therefore, in order to use the junction temperature below 100 ° C. The thickness of the insulating layer 15 needs to be 90 μm or less. On the other hand, when the thickness of the insulating layer 15 is reduced, the light is transmitted through the insulating layer 15, so that the reflectance is lowered. As shown in FIG. 8, the relationship between the thickness of the insulating layer 15 and the total luminous flux (lm) per chip of the light-emitting diode element 13, the reduction of the total luminous flux is the maximum value when the thickness of the insulating layer 15 is 120 μm. On the other hand, the thickness of the insulating layer 15 is considered to be 30 μm or more because it is desired to suppress it to about 10%. Therefore, the thickness of the insulating layer 15 is preferably in the range of 30 μm to 90 μm, and heat dissipation can be improved while ensuring the reflectance.

  The circuit pattern layer 16 has a cathode-side and anode-side circuit pattern (wiring pattern) made of an alloy of Cu and Ni, Au, Ag, or the like for each position where each light-emitting diode element 13 is located. 16a and 16b are formed.

  The reflector 17 is integrally formed by pouring a resin such as PBT (polybutylene terephthalate), PPA (polyphthalamide), or PC (polycarbonate) onto one surface of the substrate 14, and is arranged at each position where each light emitting diode element 13 is disposed. In addition, a plurality of accommodating portions 19 for accommodating the respective light emitting diode elements 13 are formed. Each accommodating portion 19 is formed in a truncated cone shape that gradually expands toward the opposite side with respect to the substrate 14. A lens holder portion 20 for fixing a lens (not shown) is formed around the housing portion 19 concentrically.

  The white insulating layer 15 is located on the bottom of each housing part 19 so as to face most of the central area of the bottom of the housing part 19, and the circuit patterns 16 a and 16 b are arranged in the peripheral area of the bottom part of the housing part 19. The end of the minimum size that allows wire bonding is located. In other words, the ratio of the surface area of the insulating layer 15 facing the accommodating portion 19 is greater than the ratio of the surface area of the circuit pattern layer 16.

  Each light emitting diode element 13 is disposed on the insulating layer 15 using an adhesive or the like in the central region of the accommodating portion 19, and each electrode of the light emitting diode element 13 and each circuit pattern 16a, 16b are bonded by wire bonding. 21 is electrically connected.

  Each accommodating portion 19 is formed with a covering layer 22 that covers the light emitting diode element 13. The covering layer 22 is formed in two layers: a diffusion layer 23 that covers the light-emitting diode element 13 and a phosphor layer 24 that is disposed on the opening side of the accommodating portion 19 above the diffusion layer 23.

  The diffusion layer 23 is made by blending a diffusing agent such as alumina (Al2O3), TiO2, BaSO4, SiO2, or Y2O3 with a thermosetting transparent resin such as a translucent silicone resin or epoxy resin. The resin is filled up to a position higher than the light emitting diode element 13 in the accommodating portion 19 and is thermally cured. A bonding surface (boundary surface) 25 between the diffusion layer 23 and the phosphor layer 24 is formed as a curved surface that is recessed toward the light emitting diode element 13 side (the lower surface side in FIG. 1). The diffusion layer 23 is not essential.

  The phosphor layer 24 is composed mainly of a yellow phosphor that receives blue light from the light-emitting diode element 13 and emits yellow fluorescence to a thermosetting transparent resin such as a translucent silicone resin or epoxy resin. Thus, after the thermosetting of the diffusion layer 23, a resin mixed with a phosphor is filled in the accommodating portion 19 and is thermoset. As the phosphor, a yellow phosphor is mainly used, but a red phosphor or the like is also blended. Note that a lighting device can be configured by combining the light emitting device 11 and a lens.

  Next, the operation of the light emitting device 11 will be described. When a predetermined DC voltage is applied from the outside between the circuit patterns 16a and 16b on the cathode side and the anode side, each light emitting diode element 13 emits blue light. This blue light emission is diffused in multiple directions by the diffusion layer 23 and then enters the phosphor layer 24, where the yellow phosphor is excited from multiple directions to emit yellow light. Then, the blue light from the light emitting diode element 13 and the yellow light from the yellow phosphor are mixed and become white light, which is emitted from the housing portion 19 to the outside.

  Therefore, in the light emitting device 11, minute light emission of the light emitting diode element 13 is diffused in multiple directions by the diffusion layer 23, and the yellow phosphor of the phosphor layer 24 is excited from multiple directions to emit yellow light. Since white light is emitted by mixing light and blue light, it is possible to reduce the white light from being mixed into yellow light and blue light. Further, since this resin has a high heat dissipation property with a thermal conductivity of 1.0 to 9.0 [W / m · K], the heat of the light emitting diode element 13 is conducted to the resin substrate 14 to dissipate heat. Can be improved. For this reason, it is possible to suppress a decrease in the light emission efficiency of the light emitting diode element 13 due to a temperature rise. Further, since the light traveling from the light emitting diode element 13 toward the substrate 14 can be efficiently reflected by the white insulating layer 15, the light extraction efficiency of the light emitting diode element 13 can be improved.

  In particular, the ratio of the surface area of the insulating layer 15 facing the accommodating portion 19 has a relationship greater than the ratio of the surface area of the circuit pattern layer 16, and the reflectance of the surface of the insulating layer 15 in the wavelength range of 400 to 740 nm. By being 85% or more, the light traveling from the light emitting diode element 13 toward the substrate 14 can be efficiently reflected by the white insulating layer 15, and the light extraction efficiency of the light emitting diode element 13 can be further improved.

  Next, an LED lamp (light emitting device) showing a second embodiment according to the present invention will be described. In the present embodiment, a plurality of light emitting elements are arranged in a matrix in one recess. Reference numeral 1 in FIGS. 9 and 10 denotes an LED lamp. The LED lamp 1 includes an LED chip 2 as a plurality of light emitting elements, a circuit pattern 3, a substrate 4, a reflective layer 5 as a white insulating layer, a reflector 8 as a reflector, and a phosphor layer. A phosphor-containing resin layer 9, a sheet-like phosphor layer 10, a translucent adhesive layer 21, and a light diffusion member 22 are provided to form a light emitting device. The substrate 4 and the reflector 8 cooperate to form the recess 7.

  The substrate 4 is made of a flat plate made of an insulating material such as a synthetic resin, and has a predetermined shape such as a rectangular shape in order to obtain a light emitting area required for the LED lamp 1. The reflective layer 5 has such a size that a predetermined number of LED chips 2 can be disposed, and is attached to the entire surface of the substrate 4, for example. The reflective layer 5 is formed of a white insulating material having a reflectance of 85% or more in a wavelength region of 400 nm to 740 nm. The white insulating material forming the reflective layer 5 is formed by impregnating a sheet base material with a thermosetting resin mixed with white powder such as aluminum oxide. The reflective layer 5 is bonded to one surface as the surface of the substrate 4 by its own adhesiveness.

  The circuit pattern 3 is bonded to the surface of the reflective layer 5 opposite to the surface to which the substrate 4 is bonded as an energization element to each LED chip 2. For example, in order to connect the LED chips 2 in series, the circuit pattern 3 is formed in two rows in the longitudinal direction of the substrate 4 and the reflective layer 5 at predetermined intervals as shown in FIG. An end side circuit pattern 3a located on one end side of one circuit pattern 3 row is integrally formed with a power feeding pattern portion 3c. Similarly, an end side located on one end side of the other circuit pattern 3 row side. The circuit pattern 3a is integrally formed with a power feeding pattern portion 3d. The power feeding pattern portions 3 c and 3 d are provided side by side at one end in the longitudinal direction of the reflective layer 5 and are separated from each other and insulated by the reflective layer 5. Electric wires (not shown) reaching the power supply are individually connected to the power supply pattern portions 3c and 3d by soldering or the like.

  Each LED chip 2 is made of a double-wire type LED chip using, for example, a nitride semiconductor, does not have a reflective film, and can emit light both in the thickness direction. Each LED chip 2 is disposed between the circuit patterns 3 adjacent to each other in the longitudinal direction of the substrate 4, and is bonded to the same surface of the white reflective layer 5 by a translucent adhesive layer 21. By this adhesion, the circuit pattern 3 and the LED chip 2 are arranged in a straight line on the same surface of the reflective layer 5, so that the side surfaces 2 a and 2 b of the LED chip 2 positioned in this arrangement direction are close to the circuit pattern 3. It is provided so as to face each other. The thickness of the translucent adhesive layer 21 is 5 μm or less. For the translucent adhesive layer 21, for example, a translucent adhesive having a thickness of 5 μm or less and a light transmittance of 70% or more, such as a silicone resin adhesive, can be suitably used.

  The electrode of each LED chip 2 and the circuit pattern 3 arranged close to both sides of the LED chip 2 are connected by a bonding wire 6 provided by wire bonding. Further, the end side circuit patterns located on the other end side of the two rows of circuit patterns 3 rows are also connected by wire bonding. Therefore, in this embodiment, each LED chip 2 is connected in series.

  The reflector 8 is not provided individually for each one or several LED chips 2, but is a single one that surrounds all the LED chips 2 on the reflective layer 5, and has a frame, for example, shown in FIG. It is formed with a rectangular frame. The reflector 8 is bonded to the reflective layer 5, and a plurality of LED chips 2 and circuit patterns 3 are housed therein, and the pair of power supply pattern portions 3 c and 3 d are positioned outside the reflector 8. Yes.

  The reflector 8 is formed of, for example, a synthetic resin, and its inner peripheral surface is a reflecting surface. The reflecting surface of the reflector 8 can be formed by depositing or plating a metal material having a high reflectance such as Al or Ni, or by applying a white paint having a high visible light reflectance. Alternatively, white powder can be mixed into the molding material of the reflector 8 to make the reflector 8 itself white with high visible light reflectivity. As said white powder, white fillers, such as aluminum oxide, titanium oxide, magnesium oxide, barium sulfate, can be used. It is desirable that the reflecting surface of the reflector 8 is formed so as to gradually open in the irradiation direction of the LED lamp 1.

  The phosphor-containing resin layer 9 is made of a translucent material such as a transparent silicone resin or transparent glass. The phosphor particles used for forming the phosphor-containing resin layer 9 have an average particle diameter (D50) of 15 μm or more and 30 μm or less as described above, and the liquid transparent resin has a viscosity of 1 Pa · s or more and 3 Pa · s. The following are used. The liquid transparent resin containing the phosphor is solidified in the reflector 8 by evenly filling the surface of the reflective layer 5 and the LED chips 2 and bonding wires 6 arranged in a straight line. It is considered that the liquid transparent resin that has flowed between the surface of the reflective layer 5 and the bonding wire 6 has spread to each LED chip 2 and the bonding wire 6 due to a capillary phenomenon or the like. In addition, when the liquid transparent resin used for forming the phosphor-containing resin layer 9 is composed of two or more liquid transparent resins, the mixture of the two or more liquid transparent resins is mixed. The viscosity may be 1 Pa · s or more and 3 Pa · s or less. For example, in the present embodiment in which each LED chip 2 is a blue LED chip, a phosphor (illustrated) that converts the wavelength of primary light (blue) emitted from these elements to produce yellow light as secondary light having a different wavelength. However, as a preferred example, it is mixed in a substantially uniformly dispersed state.

  In the light emitting device of the present embodiment, the phosphor-containing resin layer 9 can evenly cover the LED chips 2 arranged side by side on the same surface on the white reflective layer 5, so that it is in a plurality of recesses on the substrate. Compared with the case where the light emitting elements are arranged one by one, the change in the color temperature of the entire light emitting device 1 can be suppressed, and the light emitting device 1 can be manufactured with a high yield. Moreover, since the average particle diameter (D50) of each phosphor is 15 μm or more and 30 μm or less, and the viscosity of the transparent resin before curing is 1 Pa · s or more and 3 Pa · s or less, it is injected onto the white reflective layer 5. It is possible to suppress the precipitation and deposition of the phosphor particles from the time of curing to the time of curing, thereby reducing the light emission efficiency and further emitting light uniformly.

  The sheet-like phosphor layer 10 has a relatively large surface area of the phosphor-containing resin layer 9 of the second embodiment and is in a state in which dust or the like is likely to adhere because it has a soft property. In order to prevent adhesion of dust and the like by covering this with the sheet-like phosphor layer 10, it is desirable to increase the hardness of the sheet-like phosphor layer 10. Specifically, silicone resin and silicone rubber are suitable.

  With this combination, part of the blue light emitted from the LED chip 2 passes through the phosphor-containing resin layer 9 without hitting the phosphor, while each fluorescent light hit by the blue light emitted from the LED chip 2 The body absorbs blue light, emits yellow light and red light, and the yellow light and red light are transmitted through the phosphor-containing resin layer 9 and the sheet-like phosphor layer 10, so that these two complementary colors are present. White light in which the average color rendering index Ra of the LED lamp 1 is improved by mixing color and red light can be realized.

  The light diffusion member 22 combined with the LED lamp 1 has a flat plate shape and is disposed in front of the reflector 8. Note that the reflector 8 may be provided with an extension projecting forward and the light diffusing member 22 may be supported there, or may be supported by a lighting fixture body (not shown) in which the LED lamp 1 is housed. The light diffusion member 22 has a difference between the transmittance of blue light of 400 nm to 480 nm and the transmittance of yellow light of 540 nm to 650 nm within 10%, and the transmittance of visible light is 90% or more 100 Those having a light diffusion performance of less than% can be suitably used. By using such a light diffusing member 22, the blue primary light and the yellow secondary light can be mixed by the light diffusing member 22, and the light diffusing member 22 can be white in which the color unevenness is suppressed.

1 is an enlarged cross-sectional view of a part of a light-emitting device showing an embodiment of the present invention. The enlarged front view which abbreviate | omitted some light emitting devices same as the above. The front view of a light-emitting device same as the above. Sectional drawing of a light-emitting device same as the above. The graph which shows the total light reflectance of the white resin material used for a light-emitting device same as the above. The table | surface which shows the reflectance and thermal resistance for every thickness of the insulating layer of a light emitting device same as the above. The table | surface which shows the temperature rise for every thickness of the insulating layer of a light-emitting device same as the above. The table | surface which shows the total light beam and ratio for each thickness of the insulating layer of a light-emitting device same as the above. Sectional drawing which shows the structure of 2nd Embodiment which applied the light-emitting device of this invention to the LED lamp. F2-F2 sectional view taken on the line of FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Light emitting device, 13 ... Light emitting diode element as a light emitting element, 14 ... Resin substrate, 15 ... Insulating layer, 16 ... Circuit pattern layer, 17 ... Reflector, 19 ... Housing part.

Claims (7)

A resin substrate having a thermal conductivity of 1.0 to 9.0 [W / m · K];
A white insulating layer provided on the resin substrate;
A circuit pattern layer provided on the insulating layer;
A light emitting device disposed on the insulating layer and electrically connected to the circuit pattern layer;
A light-emitting device comprising: A resin substrate having a thermal conductivity of 1.0 to 9.0 [W / m · K];
A white insulating layer provided on the resin substrate;
A circuit pattern layer provided on the insulating layer;
A receiving portion is provided on the insulating layer and the circuit pattern layer, and an opening is provided on the insulating layer and the circuit pattern layer corresponding to the position where the light emitting element is provided, and the circuit pattern layer is positioned in the peripheral area in the receiving portion. A structured reflector;
A light emitting element disposed on the insulating layer in the central region in the housing portion of the reflector and electrically connected to the circuit pattern layer located in the peripheral region in the housing portion;
A light-emitting device comprising:   The light emitting device according to claim 2, wherein a ratio of a surface area of the insulating layer facing the housing portion is larger than a ratio of a surface area of the circuit pattern layer.   4. The light emitting device according to claim 1, wherein the reflectance of the surface of the insulating layer is 85% or more in a wavelength range of 400 to 740 nm.   The light emitting device according to any one of claims 1 to 4, wherein the resin substrate contains 50 to 90 mass% of an inorganic filler in a synthetic resin base material.   The light emitting device according to claim 5, wherein the inorganic filler has a substantially spherical shape with a diameter of 100 μm or less.   The light emitting device according to claim 1, wherein the insulating layer has a thickness in a range of 30 μm to 90 μm.

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