JP4091926B2 - Light emitting device and lighting device - Google Patents

Description

  The present invention relates to a light emitting element storage package for storing a light emitting element, a light emitting device, and an illumination device.

  A light emitting element housing package for housing a light emitting element 15 such as a conventional light emitting diode (LED) is shown in FIG. In FIG. 3, the light emitting element storage package has a mounting portion 11a for mounting the light emitting element 15 at the center of the upper surface, and is formed from the mounting portion 11a to the outer surface of the substrate. A base 11 made of an insulator on which a conductor layer 17 made of a lead terminal, metallized wiring, or the like is electrically connected, and a through hole 12a that is bonded and fixed to the upper surface of the base 11 and whose upper opening is larger than the lower opening. While being formed, the inner peripheral surface is mainly composed of a frame-like reflecting member 12 which is a reflecting surface 12b that reflects light emitted from the light emitting element 15.

  Then, the light emitting element 15 is mounted on the mounting portion 11a of the light emitting element storage package and the electrode of the light emitting element 15 is electrically connected to the conductor layer 17, so that the light emitting element 15 is covered inside the reflecting member 12. A light emitting device is obtained by filling the transparent member 13 containing a phosphor that excites light emitted from the light emitting element 15 and converts it to a long wavelength.

  This light-emitting device can obtain white light by converting the wavelength of near-ultraviolet light or blue light emitted from the light-emitting element 15 with a plurality of phosphors such as red, green, blue, and yellow contained in the transparent member 13. it can.

  The substrate 11 is made of an aluminum oxide sintered body (alumina ceramic), an aluminum nitride sintered body, a mullite sintered body, ceramics such as glass ceramics, or a resin such as epoxy resin. When the substrate 11 is made of ceramics, the conductor layer 17 is formed on its upper surface by firing a metal paste made of tungsten (W), molybdenum (Mo) -manganese (Mn) or the like at a high temperature. When the base 11 is made of a resin, lead terminals made of copper (Cu), iron (Fe) -nickel (Ni) alloy, etc. are molded and fixed inside the base 11.

  The reflecting member 12 has a frame shape in which a through hole 12a having an upper opening larger than the lower opening is formed and a reflecting surface 12b for reflecting light is provided on the inner peripheral surface. Specifically, it consists of metals such as aluminum (Al) and Fe-Ni-cobalt (Co) alloys, ceramics such as alumina ceramics or resins such as epoxy resins, and molding technologies such as cutting, die molding or extrusion molding. It is formed by.

  Further, the reflecting surface 12b of the reflecting member 12 is coated by polishing or flattening the inner peripheral surface of the through hole 12a or by depositing a metal such as Al on the inner peripheral surface of the through hole 12a by vapor deposition or plating. As a result, the light from the light emitting element 15 can be efficiently reflected. Then, the reflecting member 12 is an upper surface of the base 11 so that the mounting portion 11a is surrounded by the inner peripheral surface of the reflecting member 12 with a bonding material such as a conductive adhesive such as solder or silver (Ag) solder or a resin adhesive. To be joined.

  The light emitting element 15 is electrically connected to the conductor layer 17 disposed on the mounting portion 11a via an electrode provided on the lower surface of the light emitting element 15. The electrode of the light emitting element 15 and the conductor layer 17 are joined by a conductive adhesive 18 such as solder or Ag paste (resin containing Ag particles).

  The transparent member 13 is made of a transparent resin such as an epoxy resin or a silicone resin containing a phosphor, and is filled inside the reflecting member 12 so as to cover the light emitting element 15 with an injection machine such as a dispenser and thermally cured in an oven. The light having the desired wavelength spectrum can be extracted by converting the long wavelength of the light from the light emitting element 15 by the phosphor.

  This light-emitting device is used as a light-emitting device by activating the light-emitting element 15 by a current voltage supplied from an external electric circuit (not shown) to emit visible light. The applicable range is used for various indicators, optical sensors, displays, photocouplers, backlight light sources, optical print heads, and the like.

In recent years, there has been an increase in the use of the above light emitting devices for illumination, and there is a demand for light emitting devices with higher characteristics in terms of radiation intensity and heat dissipation characteristics. In addition, in a light-emitting device using a light-emitting element, there are many places where long life is expected.
Japanese Patent Laid-Open No. 2003-37298

  However, in the conventional light emitting device, when the light emitting element 15 is bonded and fixed to the conductor layer 17 of the mounting portion 11a, the conductive adhesive 18 protrudes from the conductor layer 17 and spreads. Since the thickness is likely to vary, there is a problem that the light emitting element 15 is easily bonded in a tilted state. When the light emitting element 15 is mounted on the mounting portion 11a in an inclined state, it becomes difficult to reflect the light emitted from the light emitting element 15 at a desired radiation angle by the reflecting member 12 and to emit the light to the outside satisfactorily. The problem is that the radiation intensity of the light emitted from the light tends to decrease.

  In addition, if the thickness of the conductive adhesive 18 for fixing the light emitting element 15 on the conductor layer 17 varies, the heat generated from the light emitting element 15 is efficiently transferred to the outside via the conductive adhesive 18 and the substrate 11. Difficult to diffuse well. As a result, the temperature of the light emitting element 15 rises, the radiant intensity of light emitted from the light emitting element 15 tends to decrease, and the radiant intensity of light emitted from the light emitting device cannot be kept stable. Was.

  Further, the conductive adhesive 18 for joining the conductor layer 17 and the light emitting element 15 flows out from the outer periphery of the light emitting element 15, and the conductive adhesive 18 that flows out covers the upper surface of the substrate 11. The problem is that the light emitted from the light emitting element 15 and the phosphor is easily absorbed by the conductive adhesive 18 from which the light has flowed out, and the emission intensity of the light emitted from the light emitting device is reduced, and the luminance and color rendering are likely to be reduced. Had a point.

  Accordingly, the present invention has been completed in view of the above-described conventional problems, and an object thereof is to provide a light emitting device having high radiation intensity and excellent light characteristics such as luminance and color rendering.

The present invention includes a base, a conductor layer formed on the base, a convex portion formed on the conductor layer, and electrically connected to the conductor layer via a conductive adhesive. And a light emitting element arranged. The convex portion is made of an insulating material, is located on the inner side of the outer periphery of the light emitting element, and is disposed in parallel to the four sides of the light emitting element.

  The light-emitting device of the present invention includes the light-emitting element storage package having the above configuration, a light-emitting element mounted on the mounting portion via the conductive adhesive, and a transparent member that covers the light-emitting element. It is characterized by.

  The illuminating device of the present invention is characterized in that the light emitting device of the present invention is installed in a predetermined arrangement.

  The light emitting element storage package of the present invention includes a base having a light emitting element mounting portion at the center of the upper surface, a frame-shaped reflecting member provided around the mounting portion on the outer periphery of the upper surface of the base, and a mounting portion. And a conductive layer to which the light emitting element is electrically connected via a conductive adhesive, and the conductor layer has a convex portion formed on an upper surface located inside the outer periphery of the light emitting element. Thus, the light emitting element can be lifted above the conductor layer by the convex portion, and a gap can be reliably provided between the lower surface of the light emitting element and the upper surface of the conductor layer. As a result, the conductive adhesive can be prevented from being swept away by the weight of the light emitting element and protruding from the conductive layer, and the conductive adhesive is formed on the conductive layer to have a uniform thickness. Can be placed horizontally. As a result, the light emitting element emits light at a desired emission angle, the light emitted from the light emitting element is reflected by the reflecting member at a desired emission angle, and is emitted to the outside. can do.

  In addition, the conductive adhesive can be formed on the conductor layer to have a uniform thickness, and the light emitting element can be horizontally placed on the conductor layer, so that the heat generated from the light emitting element can be removed from the conductive adhesive and the substrate. It is also possible to dissipate efficiently to the outside through the route. As a result, the temperature of the light emitting element can always be kept stable, and the radiation intensity of light emitted from the light emitting element can be kept stable in a high state.

  Further, the conductive adhesive can be effectively prevented from flowing out of the outer periphery of the light emitting element and can be held below the light emitting element, and the light emitted from the light emitting element is outside of the outer periphery of the light emitting element. Can be effectively prevented from being absorbed by the conductive adhesive material that has flowed into the substrate. As a result, it is possible to provide a light emitting device having high radiation intensity and excellent light characteristics such as luminance and color rendering.

  The light-emitting device of the present invention includes the light-emitting element storage package having the above structure, a light-emitting element mounted on the mounting portion via a conductive adhesive, and a transparent member that covers the light-emitting element. The light emitting device using the light emitting element storage package of the invention has high radiation intensity and excellent light characteristics such as luminance and color rendering.

  Since the light emitting device of the present invention is installed in a predetermined arrangement, the lighting device of the present invention uses light emission by recombination of electrons of a light emitting element made of a semiconductor. Thus, a small illuminating device that can have lower power consumption and longer life than the existing illuminating device can be obtained. As a result, fluctuations in the center wavelength of light generated from the light emitting element can be suppressed, light can be emitted with a stable radiant light intensity and radiant light angle (light distribution distribution) over a long period of time, and an irradiation surface It is possible to provide a lighting device in which uneven color and uneven illuminance distribution are suppressed.

  In addition, the light emitting device of the present invention is installed in a predetermined arrangement as a light source, and by installing a reflection jig, an optical lens, a light diffusing plate, etc. optically designed in an arbitrary shape around these light emitting devices, It can be set as the illuminating device which radiates | emits the light of this light distribution.

  The light emitting element storage package and the light emitting device of the present invention will be described in detail below. FIG. 1 is a cross-sectional view showing an example of an embodiment of a light emitting device of the present invention. In this figure, 1 is a substrate, 2 is a reflecting member, 3 is a transparent member, 7 is a conductor layer, and 9 is a convex part, and these mainly constitute a light emitting device.

  The light emitting element storage package of the present invention includes a base 1 having a mounting portion 1a for the light emitting element 5 at the center of the upper surface, and a frame-shaped reflecting member provided around the mounting portion 1a on the outer periphery of the upper surface of the base 1 2 and a conductor layer 7 formed on the mounting portion 1a, to which the light emitting element 5 is electrically connected via the conductive adhesive 8, and the conductor layer 7 is formed from the outer periphery of the light emitting element 5. Further, a convex portion 9 is formed on the upper surface located inside.

  The substrate 1 in the present invention is made of alumina ceramic, aluminum nitride sintered body, mullite sintered body, ceramic such as glass ceramic, or resin such as epoxy resin. The base body 1 has a mounting portion 1a on which the light emitting element 5 is mounted on the upper main surface.

  The mounting portion 1a is formed with a conductor layer 7 for mounting and fixing the light emitting element 5 on the base 1 and to which the light emitting element 5 is electrically connected. The conductor layer 7 is led out to the outer surface of the light emitting device through a wiring layer (not shown) formed in the base 1, and the lead-out portion of the outer surface of the light emitting device is connected to the external electric circuit board. As a result, the light emitting element 5 and the external electric circuit are electrically connected.

  When the substrate 1 is made of ceramic, the conductor layer 7 is formed by firing a metal paste made of W, Mo—Mn, Cu, Ag, or the like on the upper surface of the substrate 1 at a high temperature. When the substrate 1 is made of resin, lead terminals made of Cu, Fe—Ni alloy, etc. are molded and fixed inside the substrate 1.

  The convex portion 9 is provided on the conductor layer 7 on the upper surface located inside the outer periphery of the light emitting element 5. The convex portion 9 may be a conductive material or an insulating material. When the convex portion 9 is made of an insulating ceramic material, for example, a ceramic paste mainly composed of a material forming the base body 1 is printed and applied, and is fired at a high temperature simultaneously with the metal paste to be the conductor layer 7. The When the substrate 1 is made of a resin, for example, the convex portion 9 is made of the same material as the substrate 1 and is formed simultaneously with the substrate 1 by molding.

  Further, when the convex portion 9 is made of a conductive material, it can be produced by printing and applying a metal paste on the upper surface of the conductor layer 7 and firing, or by providing a protruding portion on the lead terminal by cutting or the like.

  Thus, since the convex part 9 is formed in the conductor layer 7 on the upper surface located inside the outer periphery of the light emitting element 5, the light emitting element 5 is lifted above the conductor layer 7 by the convex part 9, and the light emitting element A gap can be reliably provided between the lower surface of 5 and the upper surface of the conductor layer 7. As a result, the conductive adhesive 8 can be prevented from being swept away by the weight of the light emitting element 5 and protruding from the conductor layer 7 and spreading, and the conductive adhesive 8 is formed on the conductor layer 7 with a uniform thickness. The light emitting element 5 can be placed horizontally on the conductor layer 7. As a result, light is emitted from the light emitting element 5 at a desired emission angle, and the light emitted from the light emitting element 5 is reflected by the reflecting member 2 at a desired emission angle and emitted to the outside. It can be strong.

  Further, the conductive adhesive 8 is formed on the conductor layer 7 to have a uniform thickness, and the light emitting element 5 can be placed horizontally on the conductor layer 7, so that the heat generated from the light emitting element 5 can be made conductive. It is also possible to efficiently dissipate to the outside via the adhesive 8 and the substrate 1. As a result, the temperature of the light emitting element 5 can always be kept stable, and the radiation intensity of the light emitted from the light emitting element 5 can be kept stable in a high state.

  Further, the conductive adhesive 8 can be effectively prevented from flowing out of the outer periphery of the light emitting element 5 and can be held below the light emitting element 5, and the light emitted from the light emitting element 5 can be retained. Can be effectively prevented from being absorbed by the conductive adhesive 8 that has flowed out of the outer periphery. As a result, it is possible to provide a light emitting device having high radiation intensity and excellent light characteristics such as luminance and color rendering.

  The height of the convex part 9 is good to be 0.01-0.1 mm. As a result, a good meniscus of the conductive adhesive 8 can be formed between the light emitting element 5 and the conductor layer 7, the outflow of the conductive adhesive 8 can be more effectively prevented, and the light emitting element 5 and the conductor layer 7 can be prevented from flowing out. Bonding strength can be further increased.

  FIG. 2 shows an enlarged plan view of the conductor layer 7 and the convex portion 9. As shown in FIG. 2A, for example, a plurality of hemispherical convex portions 9 are provided on the upper surface of the conductor layer 7 located inside the outer periphery of the light emitting element 5. In addition, as shown in FIG. 2B, on the upper surface of the conductor layer 7 positioned on the inner side of the outer periphery of the light emitting element 5, the rectangular projection 9 is parallel to the outer periphery of the light emitting element 5. It may be provided. As shown in FIGS. 2A and 2B, by providing a plurality of protrusions 9, a gap is surely provided between the lower surface of the light emitting element 5 and the upper surface of the conductor layer 7, and the upper surface of the conductor layer 7. A good meniscus of the conductive adhesive 8 can be formed between the light emitting element 5 and the lower surface of the light emitting element 5. Here, it is important to arrange the convex portions 9 in a balanced manner so that the light emitting element 5 is placed horizontally with respect to the conductor layer 7. Thus, by providing the convex part 9 smaller than the lower surface of the light emitting element 5 on the conductor layer 7, even if the conductor layer 7 and the lower surface of the light emitting element 5 are joined via the conductive adhesive 8, It is possible to prevent the conductive adhesive 8 for bonding and fixing the light emitting element 5 to the conductor layer 7 from protruding from the conductor layer 7 and spreading, and to uniformly spread the conductive adhesive 8 on the mounting portion 1a. Can be placed horizontally on the placement portion 1a.

  The electrode provided on the lower surface of the light emitting element 5 is connected via a conductive adhesive 8 such as Ag paste, gold (Au) -tin (Sn) solder.

  The conductor layer 7 should be coated with a metal having excellent corrosion resistance, such as Ni or Au, with a thickness of about 1 to 20 μm on the exposed surface, effectively preventing oxidative corrosion of the conductor layer 7. In addition, the connection between the light emitting element 5 and the conductor layer 7 can be strengthened. Therefore, for example, a Ni plating layer having a thickness of about 1 to 10 μm and an Au plating layer having a thickness of about 0.1 to 3 μm are sequentially deposited on the exposed surface of the conductor layer 7 by an electrolytic plating method or an electroless plating method. More preferably.

  Further, the reflecting member 2 is attached to the upper surface of the substrate 1 by a bonding material such as solder, a brazing material such as Ag brazing, or an adhesive such as an epoxy resin. The reflection member 2 has a through hole 2a formed at the center. Preferably, the inner peripheral surface of the through hole 2a is a reflecting surface 2b that efficiently reflects light emitted from the light emitting element 5 or the phosphor.

  The reflecting surface 2b is formed by performing a cutting process, a mold forming process, a polishing process, or the like on the reflecting member 2 to obtain a smooth surface having a high light reflection efficiency. Alternatively, a highly reflective metal thin film such as Al, Ag, Au, platinum (Pt), titanium (Ti), chromium (Cr), or Cu is formed on the inner peripheral surface of the through hole 2a by, for example, plating or vapor deposition. By doing so, the reflective surface 2b may be formed. When the reflecting surface 2b is made of a metal that is easily discolored by oxidation such as Ag or Cu, an Ni plating layer having a thickness of about 1 to 10 μm and an Au plating layer having a thickness of about 0.1 to 3 μm are formed on the surface. Is preferably deposited sequentially by electrolytic plating or electroless plating. Thereby, the corrosion resistance of the reflective surface 2b improves.

  Further, the arithmetic average roughness Ra on the surface of the reflecting surface 2b is preferably 0.004 to 4 μm, whereby the reflecting surface 2b can favorably reflect the light of the light emitting element 5 or the phosphor. When Ra exceeds 4 μm, it becomes difficult to uniformly reflect the light of the light emitting element 5 and it becomes easy to diffusely reflect inside the light emitting device. On the other hand, if it is less than 0.004 μm, it tends to be difficult to form such a surface stably and efficiently.

  In addition, the reflecting surface 2b has, for example, a linear inclined surface as shown in FIG. 1 whose longitudinal cross-sectional shape spreads outward as it goes upward, and a curved slope that spreads outward as it goes upward Examples of the shape include a surface and a rectangular surface.

  Thus, in the light emitting element storage package of the present invention, the light emitting element 5 is mounted on the mounting portion 1 a and is electrically connected to the conductor layer 7 via the conductive adhesive 8, and the light emitting element 5 is covered with the transparent member 3. Thus, a light emitting device is obtained.

  The transparent member 3 of the present invention is made of a transparent resin such as an epoxy resin or a silicone resin. The transparent member 3 is filled in the reflecting member 2 so as to cover the light emitting element 5 with an injection machine such as a dispenser, and is thermally cured in an oven or the like.

  The transparent member 3 may contain a phosphor that can convert the wavelength of light from the light emitting element 5.

  Further, the upper surface of the transparent member 3 is preferably convex upward as shown in FIG. Thereby, the path length which the light radiated | emitted from the light emitting element 5 in various directions permeate | transmits the transparent member 3 can be made near, and it can suppress effectively that the nonuniformity of radiation intensity arises.

  In addition, the light emitting device of the present invention is a circular shape in which one device is installed in a predetermined arrangement, or a plurality of light emitting devices, for example, a lattice shape, a staggered shape, a radial shape, or a plurality of light emitting devices. In addition, a lighting device can be obtained by installing the light emitting device groups in a plurality of concentric shapes so as to have a predetermined arrangement. Thereby, since light emission by recombination of electrons of the light emitting element 5 made of a semiconductor is used, it is possible to achieve lower power consumption and longer life than a lighting device using a conventional discharge, and generate less heat. It can be set as a small illuminating device. As a result, fluctuations in the center wavelength of the light generated from the light emitting element 5 can be suppressed, and light can be irradiated with a stable radiant light intensity and radiant light angle (light distribution) over a long period of time. It can be set as the illuminating device by which the color nonuniformity in the surface and the bias of illuminance distribution were suppressed.

  In addition, the light emitting device of the present invention is installed in a predetermined arrangement as a light source, and by installing a reflection jig, an optical lens, a light diffusing plate, etc. optically designed in an arbitrary shape around these light emitting devices, It can be set as the illuminating device which can radiate | emit the light of this light distribution.

  For example, a plurality of light emitting devices 20 are arranged in a plurality of rows on the light emitting device driving circuit board 22 as shown in the plan view and the cross-sectional view shown in FIGS. 4 and 5, and are optically designed in an arbitrary shape around the light emitting device 20. In the case of an illuminating device in which a reflecting jig 21 is installed, in a plurality of light emitting devices 20 arranged on one adjacent row, an arrangement in which the interval between adjacent light emitting devices 20 is not the shortest, so-called zigzag shape It is preferable that That is, when the light emitting devices 20 are arranged in a grid, glare is strengthened by arranging the light emitting devices 20 as light sources on a straight line, and such a lighting device enters human vision. Thus, discomfort and eye damage are likely to occur, but by forming a staggered pattern, glare is suppressed and discomfort and damage to the eyes of the human eye can be reduced. Furthermore, since the distance between adjacent light emitting devices 20 is increased, thermal interference between adjacent light emitting devices 20 is effectively suppressed, and heat in the light emitting device drive circuit board 22 on which the light emitting devices 20 are mounted is reduced. Clouding is suppressed, and heat is efficiently dissipated outside the light emitting device 20. As a result, it is possible to manufacture a long-life lighting device with stable optical characteristics over a long period of time with little obstacles to human eyes.

  In addition, the lighting device is a concentric arrangement of a group of circular or polygonal light emitting devices 20 composed of a plurality of light emitting devices 20 on the light emitting device driving circuit board 22 as shown in the plan view and the sectional view shown in FIGS. In the case of the illuminating device formed in a plurality of groups, it is preferable that the number of light emitting devices 20 arranged in one circular or polygonal light emitting device 20 group is increased from the center side of the illuminating device toward the outer peripheral side. As a result, more light emitting devices 20 can be arranged while maintaining an appropriate interval between the light emitting devices 20, and the illuminance of the lighting device can be further improved. Further, it is possible to reduce the density of the light emitting device 20 in the central portion of the lighting device, and to suppress heat accumulation in the central portion of the light emitting device driving circuit board 22. Therefore, the temperature distribution in the light emitting device driving circuit board 22 is uniform, heat is efficiently transmitted to the external electric circuit board on which the lighting device is installed and the heat sink, and the temperature rise of the light emitting device 20 can be suppressed. As a result, the light emitting device 20 can operate stably over a long period of time, and a long-life lighting device can be manufactured.

  Examples of such lighting devices include general lighting fixtures, chandelier lighting fixtures, residential lighting fixtures, office lighting fixtures, store lighting, display lighting fixtures, street lighting fixtures, used indoors and outdoors. Guide lights and signaling devices, stage and studio lighting, advertising lights, lighting poles, underwater lighting, strobe lights, spotlights, security lights embedded in power poles, emergency lighting equipment, flashlights, Examples include electronic bulletin boards and the like, backlights for dimmers, automatic flashers, displays and the like, moving image devices, ornaments, illuminated switches, optical sensors, medical lights, in-vehicle lights, and the like.

  In addition, this invention is not limited to the example of the above embodiment, If it is in the range which does not deviate from the summary of this invention, it will not interfere at all.

  For example, a plurality of light emitting elements 5 may be provided on the substrate 1 in order to improve the radiation intensity. It is also possible to arbitrarily adjust the angle of the reflecting surface 2b and the distance from the upper end of the reflecting surface 2b to the upper surface of the transparent member 3, thereby obtaining better color rendering by providing a complementary color gamut. it can.

  Further, the lighting device of the present invention is not limited to one in which a plurality of light emitting devices 20 are installed in a predetermined arrangement, but may be one in which one light emitting device 20 is installed in a predetermined arrangement.

It is sectional drawing which shows an example of embodiment of the light-emitting device of this invention. (A) is an enlarged plan view which shows an example of embodiment about the conductor layer and convex part in the light-emitting device of this invention, (b) is another example of embodiment about the conductor layer and convex part in the light-emitting device of this invention. FIG. It is sectional drawing which shows the conventional light-emitting device. It is a top view which shows an example of embodiment of the illuminating device of this invention. It is sectional drawing of the illuminating device of FIG. It is a top view which shows the other example of embodiment of the illuminating device of this invention. It is sectional drawing of the illuminating device of FIG.

Explanation of symbols

1: Base 1a: Placement part 2: Reflecting member 3: Transparent member 5: Light emitting element 7: Conductive layer 8: Conductive adhesive 9: Convex part
20: Light emitting device
21: Reflective jig
22: Light-emitting device drive circuit board

Claims (4)

A substrate;
A conductor layer formed on the substrate;
A plurality of convex portions formed on the conductor layer;
It is electrically connected to the conductor layer through a conductive adhesive, and includes a light emitting element disposed on the convex portion,
The plurality of convex portions are made of an insulating material, are located on the inner side of the outer periphery of the light emitting element, and are arranged in parallel to the four sides of the light emitting element .   The light emitting device according to claim 1, wherein the base body and the convex portion are made of ceramics.   The light emitting device according to claim 1, wherein the light emitting element is a light emitting diode. Lighting apparatus comprising the light-emitting device according to any one of claims 1-3.

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