JP2005159263A - Light-emitting device and lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device, in which the light emitted by a light-emitting element is efficiently wavelength-converted by a fluorescent material and the radiant intensity is strengthened, to yield superior light characteristics, such as on-axis brightness, luminance, and color-rendering properties. <P>SOLUTION: The light-emitting device comprises a base body 1; a reflecting member 2, in the central part of the upper-side main surface of which a convex-shaped mounting section 2b on which the light-emitting element 5 is mounted is formed, and in which a side-wall section 2a is formed, wherein the outer peripheral part of the upper-side main surface of the reflecting member 2 surrounds the mounting section 2b and the inner peripheral face of the reflecting member 2 is made to be a reflecting face 2c that reflects the light emitted from the light-emitting element 5, with the light-emitting element 5 mounted on the mounting section 2b; and a transparent member 3, which is so formed as to cover the light-emitting element 5 at the inner side of the side-wall section 2a and contains the fluorescent material 4 that wavelength-converts the light emitted by the light-emitting element 5. The lower end of the reflecting face 2c is positioned on or below the optical path line, which connects the light-emitting part that positions at the ends of the light-emitting element 5 and a corner formed by the upper face 2d and a side face of the mounting section 2b, while the distance between the upper face of the transparent member 3 and the light-emitting part is between 0.1 mm and 0.5 mm. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a light emitting device that converts the wavelength of light emitted from a light emitting element with a phosphor and emits light to the outside, and an illumination device using the same.

  Light is converted into white by converting the wavelength of near-ultraviolet light or blue light emitted from the light emitting element 15 such as a conventional light emitting diode (LED) to the long wavelength side with a plurality of phosphors 14 such as red, green, blue, and yellow. A light-emitting device that emits light is shown in FIG. In FIG. 8, the light emitting device has a mounting portion 11a for mounting the light emitting element 15 in the center of the upper surface, and leads that electrically connect the inside and outside of the light emitting device from the mounting portion 11a and its periphery. A base 11 made of an insulator on which a wiring conductor (not shown) made of a terminal, metallized wiring, or the like is formed, 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 are formed. In addition, a frame-like frame 12 whose inner peripheral surface is a reflecting surface 12b that reflects the light emitted from the light-emitting element 15, and the light that is emitted from the light-emitting element 15 that is filled in the frame 12 is excited. It is mainly composed of a transparent resin 13 containing a phosphor 14 for wavelength conversion on the wavelength side, and a light emitting element 15 mounted and fixed on the mounting portion 11a.

  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 wiring conductor is formed on the upper surface or inside thereof 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.

  Further, the frame body 12 has a frame shape in which a through hole 12a having an upper opening larger than the lower opening is formed and a reflection surface 12b that reflects light on an 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 frame body 12 is coated by polishing and 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. It is formed by wearing. The frame 12 is bonded to the upper surface of the base 11 by a soldering material such as solder, silver (Ag) brazing, or a bonding material such as a resin adhesive so as to surround the mounting portion 11a with the inner peripheral surface of the frame 12. Is done.

Then, the wiring conductor arranged around the mounting portion 11a and the light emitting element 15 are electrically connected through the electrical connection means 16 such as a bonding wire or a metal bump, and thereafter, an epoxy resin containing the phosphor 14 A transparent resin 13 such as silicone resin is filled in the frame 12 so as to cover the light emitting element 15 with an injection machine such as a dispenser, and is thermally cured in an oven, so that the light from the light emitting element 15 is extended by the phosphor 14. A light-emitting device capable of extracting light having a desired wavelength spectrum after wavelength conversion can be obtained.
Japanese Patent Laid-Open No. 2003-37298

  In recent years, it has been desired to further increase the radiation intensity of the light emitting device. However, in the conventional light emitting device, when the current value input to the light emitting element 15 is increased to increase the radiation intensity, the junction temperature (junction temperature) of the light emitting element 15 is increased and the light emission efficiency of the light emitting element 15 is increased. Since it significantly decreases, there is a problem in that a radiation intensity proportional to the input current cannot be obtained. Furthermore, there has been a problem that a stable radiation intensity cannot be obtained due to a shift in emission wavelength that is expected to be caused by heat.

  Further, in the transparent resin 13 that covers the light emitting element 15 and contains the phosphor 14 for wavelength conversion of light from the light emitting element 15, the content of the phosphor 14 is increased to improve the efficiency of wavelength conversion. Then, since the light is easily disturbed by the phosphor 14, the radiation intensity cannot be improved.

  On the other hand, when the content of the phosphor 14 is lowered, the wavelength conversion efficiency is lowered, and light having a desired wavelength cannot be obtained. As a result, there is a problem that the radiation intensity cannot be improved.

  Further, heat generated from the light emitting element 15 is easily transmitted to the frame body 12 through the base body 11, and the frame body 12 is thermally expanded and deformed due to a difference in thermal expansion between the frame body 12 and the base body 11, and the radiation angle varies. There is also a problem that the radiation intensity is reduced.

  Therefore, the present invention has been completed in view of the above-mentioned conventional problems, and its purpose is to efficiently convert the wavelength of the light emitted from the light emitting element with a phosphor and increase the radiation intensity to increase the axial luminous intensity. An object of the present invention is to provide a light-emitting device that has excellent light characteristics such as luminance and color rendering properties, and that can efficiently dissipate heat from the light-emitting element and stably maintain radiation characteristics over a long period of time.

  The light-emitting device of the present invention includes a flat substrate, a convex mounting portion that is bonded to the upper surface of the substrate, and on which the light-emitting element is mounted on the upper surface of the upper main surface. A reflective member having a side wall portion that surrounds the mounting portion on the outer peripheral portion thereof and whose inner peripheral surface is a reflective surface that reflects light emitted from the light emitting element, and is mounted on the mounting portion. And a light-transmitting member provided inside the side wall portion so as to cover the light-emitting element and containing a phosphor that converts the wavelength of light emitted from the light-emitting element. The surface is located on or below the optical path connecting the light emitting portion whose lower end is positioned at the end of the light emitting element and the corner between the upper surface and the side surface of the mounting portion, The distance between the upper surface of the optical member and the light emitting part is 0.1 to 0.5 mm. To.

  In the light emitting device of the present invention, preferably, the base is an insulator and a wiring conductor is formed from the upper surface to the outer surface, and the reflecting member penetrates between the upper and lower main surfaces around the mounting portion. A through hole located below the optical path is formed, and the electrode of the light emitting element and the wiring conductor on the upper surface of the base are electrically connected by a wire through the through hole. And

  In the light emitting device of the present invention, preferably, the through hole is filled with an insulating paste containing insulating light reflecting particles so as to be flush with the upper main surface of the reflecting member. It is characterized by that.

  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 device of the present invention has a flat base, a convex mounting portion that is bonded to the upper surface of the base, and has a light emitting element mounted on the upper surface at the center of the upper main surface. A reflecting member having a side wall portion that surrounds the mounting portion on the outer peripheral portion and whose inner peripheral surface is a reflecting surface that reflects light emitted from the light emitting element, and a light emitting element mounted on the mounting portion And a translucent member containing a phosphor that converts the wavelength of light emitted by the light emitting element, and is provided on the inner side of the side wall portion. The light-transmitting member is located on or below the optical path connecting the light emitting part located at the end of the mounting part and the corner between the upper surface and the side surface of the mounting part, and the translucent member includes the upper surface and the light emitting part. Of the light emitted from the light emitting element is reflected by the reflecting surface. It can be made very high strength with light emitted directly from the light emitting element on the upper side without. That is, the light emitted from the light emitting element is wavelength-converted with high efficiency by the phosphor contained in the translucent member having a certain thickness above the light emitting portion of the light emitting element, and the wavelength-converted light is converted into the phosphor. It can be directly emitted to the outside of the translucent member without being obstructed. As a result, the light intensity of the light emitting device can be increased, and the light characteristics such as the on-axis luminous intensity, luminance, and color rendering can be improved.

  Further, the heat generated from the light emitting element is easily transferred from the integrated mounting portion to the side wall portion. In particular, when the reflecting member is made of metal, the heat is quickly transferred to the side wall portion and the outer surface of the side wall portion. Is dissipated well to the outside. Therefore, it is possible to effectively suppress the deformation of the reflecting member due to the difference in thermal expansion between the base and the reflecting member, and it is possible to maintain the light characteristics of the emitted light well over a long period of time.

  Furthermore, since the reflecting surface is located on the optical path connecting the light emitting unit located at the end of the light emitting element and the corner between the upper surface and the side surface of the mounting unit or below the optical path, Direct light emitted from the light emitting element in the lateral direction or the lower direction can be efficiently reflected by the reflecting surface, and the emitted light intensity can be made extremely high.

  In the light emitting device of the present invention, the base is an insulator and a wiring conductor is formed from the upper surface to the outer surface, and the reflecting member penetrates between the upper and lower main surfaces around the mounting portion and is lower than the optical path Through-holes are formed, and the electrode of the light-emitting element and the wiring conductor on the upper surface of the base are electrically connected by a wire through the through-hole, so that the direct light emitted from the light-emitting element is reflected by the reflecting member It is reflected by the reflecting surface above the through hole for passing the wire provided in the wire, and it is possible to effectively prevent direct light from entering and being absorbed into the through hole and to increase the emitted light intensity. .

  In addition, the lower surface of the light emitting element can be joined to the mounting portion of the reflecting member over the entire surface, and the heat of the light emitting element can be transmitted well to the reflecting member to further improve the heat dissipation.

  The light emitting device of the present invention is filled with an insulating paste containing insulating light reflecting particles so that the inside of the through hole is flush with the upper main surface of the reflecting member. Even if light emitted from the body enters the through-hole, it can be effectively reflected upward by the light-reflecting particles, and has excellent light characteristics such as radiation intensity, axial luminous intensity, luminance, and color rendering properties of the light-emitting device It can be.

  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 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 base, 2 is a reflecting member, 3 is a translucent member containing a phosphor 4, and 5 is a light emitting element, which can mainly emit light emitted from the light emitting element 5 to the outside with directionality. A light emitting device is configured.

  The substrate 1 in the present invention is made of ceramics such as alumina ceramics, aluminum nitride sintered bodies, mullite sintered bodies, glass ceramics, resins such as epoxy resins, Fe-Ni-Co alloys, Cu-W, Al, etc. Made of metal. The substrate 1 has a function of mounting and fixing the reflecting member 2 having a mounting portion 2d for mounting the light emitting element 5 on the upper main surface.

  On the upper surface of the substrate 1, the reflecting member 2 is attached by a bonding material such as solder, a brazing material such as Ag brazing, or an adhesive such as an epoxy resin. The reflecting member 2 is formed with a convex mounting portion 2b on the upper surface of the upper main surface, on which the light emitting element 5 is mounted, and surrounds the mounting portion 2b on the outer periphery of the upper main surface. A side wall 2a having a peripheral surface that is a reflection surface 2c that reflects light emitted from the light emitting element 5 is formed. As a result, the light from the light emitting element 5 is not only directly converted to the wavelength by the phosphor 4 and directly emitted to the outside, but also the light emitted from the light emitting element 5 in the lateral direction or the like is emitted downward from the phosphor 4. The light can be uniformly and uniformly reflected by the reflecting surface 2c, and the on-axis luminous intensity, luminance, and color rendering can be effectively improved.

  The reflecting member 2 is made of alumina ceramic, aluminum nitride sintered body, mullite sintered body, ceramic such as glass ceramic, resin such as epoxy resin, or metal such as Fe-Ni-Co alloy, Cu-W, Al or the like. It is formed by performing cutting or mold forming. The reflecting surface 2c is formed by subjecting the inner peripheral surface of the side wall portion 2a of the reflecting member 2 to cutting, mold forming, or the like, or forming the inner surface of the side wall portion 2a by, for example, plating or vapor deposition. , Ag, Au, platinum (Pt), titanium (Ti), chromium (Cr), Cu, or the like may be used to form the reflective surface 2c.

  When the reflecting surface 2c 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 2c improves.

  In addition, the arithmetic average roughness Ra of the surface of the reflecting surface 2c is preferably 0.004 to 4 μm, so that the reflecting surface 2c can reflect light from the light emitting element 5 and the phosphor 4 well. When Ra exceeds 4 μm, the light of the light emitting element 5 cannot be reflected uniformly, and is irregularly reflected 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.

  The reflection surface 2c is, for example, a linear inclined surface as shown in FIGS. 1 and 2 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 as shown in FIG.

  The reflective surface 2c of the present invention is located on or below the optical path connecting the light emitting part whose lower end is located at the end of the light emitting element 5 and the corner between the upper surface 2d and the side surface of the mounting part 2b. ing. Thereby, the direct light emitted from the light emitting element 5 in the lateral direction or the lower direction can be efficiently reflected by the reflecting surface 2c, and the emitted light intensity can be made extremely high.

  The light emitting element 5 is mounted on the upper surface 2d of the mounting portion 2b, and the electrode pad of the light emitting element 5 formed on the upper surface 2d of the mounting portion 2b or the wiring conductor formed on the upper surface of the substrate 1 is used. It is electrically connected to a partly formed electrode pad. This electrode pad is led out to the outer surface of the light emitting device (the side surface and the lower surface of the substrate 1) via a wiring conductor (not shown) formed inside the substrate 1 and the reflecting member 2, and is connected to the external electric circuit board. As a result, the light emitting element 5 and the external electric circuit are electrically connected.

  Such an electrode pad is, for example, formed of a metallized layer of metal powder such as W, Mo, Cu, or Ag on the surface or inside of the base 1 or the reflecting member 2 to thereby form a lead terminal such as Fe-Ni-Co alloy. Is embedded in the substrate 1 or the reflecting member 2 or input / output terminals made of an insulating member on which wiring conductors are formed are fitted and joined to through holes provided in the substrate 1 and the reflecting member 2.

  It should be noted that a metal having excellent corrosion resistance such as Ni or gold (Au) is preferably deposited on the exposed surface of the electrode pad or wiring conductor in a thickness of about 1 to 20 μm. Oxidative corrosion can be effectively prevented, and the connection between the light emitting element 5 and the electrode pad can be strengthened. Therefore, for example, 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 sequentially deposited on the exposed surfaces of the electrode pads and wiring conductors by an electrolytic plating method or an electroless plating method. More preferably.

  In addition, the mounting portion 2b may be formed such that its side surface is perpendicular to the base body 1 as shown in FIG. 1 or is widened toward the base body 1 as shown in FIG. In the case where the light emitting element 5 is formed so as to spread outwardly, the heat generated by the light emitting element 5 can be efficiently transmitted downward from the mounting portion 2b, and the heat dissipation of the light emitting element 5 is improved to improve the operability of the light emitting element 5. It can be maintained well.

  When the reflecting member 2 is an insulating member, as shown in FIG. 1, the electrode pad formed on the light emitting element 5 and the upper surface 2d of the mounting portion 2b is flip chip bonding such as metal bump (electrical connection means 6) bonding. It is electrically connected by adopting the method. Although not shown in FIG. 1, if an electrode pad is formed on the upper surface of the reflection member 2, a wire bonding method such as a gold wire (electrical connection means 6 ') can be adopted. Preferably, the flip chip bonding method is good, and the electrode pad can be provided directly under the light emitting element 5, so that it is not necessary to provide a space for providing an electrical connection pattern on the upper surface of the substrate 1 around the light emitting element 5. . Therefore, it is possible to effectively suppress the light emitted from the light emitting element 5 from being absorbed in the space for the electrical connection pattern of the substrate 1 and the on-axis luminous intensity being lowered.

  When the substrate 1 is an insulating member, as shown in FIG. 2, it penetrates between the upper and lower main surfaces around the mounting portion 2b of the reflecting member 2 made of an insulating member or a metal member and is positioned below the optical path. A through hole 7 is formed, and the electrode of the light emitting element 5 and the wiring conductor on the upper surface of the substrate 1 are preferably electrically connected through the through hole 7 by a wire (electrical connection means 6 ′). As a result, the direct light emitted from the light emitting element 5 is reflected by the reflecting surface 2 c above the through hole 7 for passing the wire 6 ′ provided in the reflecting member 2, and the direct light is reflected in the through hole 7. It is possible to increase the intensity of the emitted light by effectively preventing the light from entering and being absorbed. Moreover, the lower surface of the light emitting element 5 can be joined to the mounting portion 2b of the reflecting member 2 over the entire surface, and the heat of the light emitting element 5 can be transmitted well to the reflecting member 2 to further improve the heat dissipation.

  The depth of the through hole 7 (thickness of the bottom of the reflecting member 2) and the opening diameter of the through hole 7 are appropriately selected in consideration of the difference in thermal expansion from the base 1, the thermal conductivity emitted by the light emitting element 5, and the like. . Further, the thickness of the bottom of the reflecting member 2 is appropriately selected also in the case shown in FIG.

  As shown in FIG. 9, the through-hole 7 is filled with an insulating paste 7 a containing insulating light reflecting particles so as to be flush with the upper main surface of the reflecting member 2. preferable. Thereby, even if the light emitted from the light emitting element 5 or the phosphor 4 enters the through-hole 7, it can be effectively reflected upward by the light reflecting particles, and the radiant intensity, axial luminous intensity, luminance, Light characteristics such as color rendering can be improved.

  The light reflecting particles contained in the insulating paste 7a are those in which Ca, Ti, Ba, Al, Si, Mg, K, O are contained in the composition of barium sulfate, calcium carbonate, alumina, silica, etc. The total reflectance of the surface is preferably 80% or more. Thereby, the light characteristics such as the radiant intensity, the axial luminous intensity, the luminance, and the color rendering properties of the light emitting device can be improved.

  The translucent member 3 is made of a transparent resin such as epoxy resin or silicone resin, glass, or the like, and contains a phosphor 4 that can convert the wavelength of light from the light emitting element 5. The translucent member 3 is filled in the reflection 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, so that light from the light emitting element 5 is transmitted by the phosphor 4. It becomes possible to extract light having a desired wavelength spectrum after wavelength conversion.

  Moreover, the translucent member 3 is provided so that the space | interval X of the upper surface and the light emission part of the light emitting element 5 may be 0.1-0.5 mm. Thereby, the wavelength of the light emitted from the light emitting element 5 is highly efficiently converted by the phosphor 4 included in the translucent member 3 having a certain thickness above the light emitting portion of the light emitting element 5, and the wavelength conversion thereof is performed. The emitted light can be directly emitted outside the translucent member 3 without being obstructed by the phosphor 4. As a result, the light intensity of the light emitting device can be increased, and the light characteristics such as the on-axis luminous intensity, luminance, and color rendering can be improved.

  When the distance X between the light emitting portion of the light emitting element 5 and the surface of the translucent member 3 is longer than 0.5 mm as shown in FIG. 3, the phosphor 4 that is close to the light emitting element 5 (shown by hatching) The phosphor 4) can directly excite the light of the light emitting element 5 to convert the wavelength, but it is difficult to directly emit the wavelength converted light to the outside of the translucent member 3. That is, it is difficult to improve the on-axis luminous intensity by obstructing the progress of light by the phosphors 4 near the surface of the translucent member 3 (the phosphors 4 other than the shaded portion in FIG. 3). .

  On the other hand, when the distance X between the light emitting portion of the light emitting element 5 and the surface of the translucent member 3 is shorter than 0.1 mm as shown in FIG. 4, it becomes difficult to efficiently convert the wavelength of the light from the light emitting element 5. The light having a wavelength with low visibility that passes through the translucent member 3 without being converted increases, and it is difficult to improve optical characteristics such as on-axis luminous intensity, luminance, and color rendering.

  Moreover, the upper surface of the translucent member 3 is preferably convex upward as shown in FIG. Thereby, also with respect to the light emitted obliquely upward from the light emitting element 5, the distance between the light emitting portion and the surface of the translucent member 3 can be set to 0.1 to 0.5 mm, and the radiation intensity can be further increased. .

  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 8 are arranged in a plurality of rows on the light emitting device driving circuit board 10 as shown in the plan view and the sectional view shown in FIGS. In the case of an illuminating device in which the reflecting jig 9 is installed, in a plurality of light emitting devices 8 arranged on adjacent rows, an arrangement in which the interval between the adjacent light emitting devices 8 is not shortest, a so-called staggered pattern. It is preferable that That is, when the light-emitting devices 8 are arranged in a grid pattern, the glare is strengthened by arranging the light-emitting devices 8 serving 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 the adjacent light emitting devices 8 is increased, thermal interference between the adjacent light emitting devices 8 is effectively suppressed, and heat in the light emitting device driving circuit board 10 on which the light emitting devices 8 are mounted is reduced. Clouding is suppressed, and heat is efficiently dissipated outside the light emitting device 8. 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 circular or polygonal light emitting device group of a plurality of light emitting devices 8 on the light emitting device driving circuit board 10 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 to increase the number of the light emitting devices 8 arranged in one circular or polygonal light emitting device group 8 toward the outer peripheral side from the center side of the illuminating device. Thereby, more light-emitting devices 8 can be arrange | positioned maintaining the space | interval of light-emitting devices 8 moderately, and the illumination intensity of an illuminating device can be improved more. In addition, the density of the light emitting device 8 in the central portion of the lighting device can be lowered to suppress heat accumulation in the central portion of the light emitting device driving circuit board 10. Therefore, the temperature distribution in the light emitting device driving circuit board 10 becomes uniform, heat is efficiently transmitted to the external electric circuit board and the heat sink on which the lighting device is installed, and the temperature rise of the light emitting device 8 can be suppressed. As a result, the light emitting device 8 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 light fixtures and signaling devices, stage and studio lighting fixtures, advertising lights, lighting poles, underwater lighting lights, strobe lights, spotlights, security lights embedded in power poles, emergency lighting fixtures, 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.

  Examples of the light-emitting device of the present invention will be described below with reference to FIGS.

  First, an alumina ceramic substrate made of a square plate having an outer shape of 2.5 × 0.8 mm and a thickness of 0.4 mm was prepared as the substrate 1. Further, as the reflecting member 2, the outer shape is a quadrangular shape with a size of 2.5 × 0.8 mm, and a cylindrical mounting portion 2b having a diameter of L (mm) is provided at the center of the upper main surface, and is positioned around the mounting portion 2b. The thickness (distance between the upper main surface and the lower main surface) is 0.2 mm, the height from the lower main surface to the outer periphery is 1.0 mm (the protruding height from the upper main surface is 0.8 mm) The member which consists of Al which has the frame-shaped side wall part 2a whose lateral thickness is 0.2 mm was prepared. The inner peripheral surface of the side wall 2a perpendicular to the base body 1 was a reflecting surface 2c having an arithmetic average roughness Ra of 0.1 μm.

  In addition, in the long side direction of the quadrangular reflecting member 2 in a top view, one piece is placed from the upper main surface to the lower main surface, one at each site between the mounting portion 2b and the side wall portion 2a on both sides of the mounting portion 2b. A through hole 7 penetrating the reflecting member 2 was formed over the surface.

  Next, an electrode made of a part of the wiring conductor was formed in a circular shape having a diameter of 0.1 mm by a metallized layer made of Mo-Mn powder at a portion corresponding to the bottom of the through hole 7 on the upper surface of the substrate 1. Then, a Ni plating layer having a thickness of 3 μm and an Au plating layer having a thickness of 2 μm were sequentially deposited on the surface. Moreover, the wiring conductor inside the base body 1 was formed by an electrical connection portion made of a through conductor, a so-called through hole. This through hole was also formed with a metallized conductor made of Mo-Mn powder in the same manner as the electrical connection pattern.

  Furthermore, a joining portion for joining the base body 1 and the reflecting member 2 with Au-tin (Sn) brazing was formed on the outer peripheral portion of the upper surface of the base body 1 over the entire circumference. This joint was obtained by depositing a Ni plating layer having a thickness of 3 μm and an Au plating layer having a thickness of 2 μm on the surface of a metallized layer made of Mo—Mn powder.

  Next, a 0.08 mm thick light emitting element 5 emitting near-ultraviolet light is bonded to the upper surface 2d of the mounting portion 2b with Au—Sn brazing, and the reflecting member 2 is bonded to the bonding portion on the upper surface of the substrate 1 with Au—Sn. The light emitting element 5 and the electrode located at the bottom of the through hole 7 were wire bonded with a gold wire and electrically connected.

  Then, a silicone resin (translucent member 3) containing three types of phosphors 4 that emit red light, green light, and blue light is applied to the reflecting member 2 in a region surrounded by the base 1 and the reflecting member 2 with a dispenser. A light emitting device as a sample was manufactured by filling up to the uppermost end of the inner peripheral surface.

  Note that the height H (mm) of the light emitting portion of the light emitting element 5 from the base body 1 can be set to various values by changing the height of the mounting portion 2b. The distance X (mm) between the parts is expressed by X = 1.0−H. Further, as shown in FIG. 6, by changing the diameter L of the mounting portion 2b, the angle of the optical path connecting the light emitting portion and the angle between the upper surface 2d and the side surface of the mounting portion 2b can be changed.

  FIG. 7 shows the results of measuring the on-axis luminous intensity of each sample with respect to the values of L and X. From the graph of FIG. 7, it was found that the amount of light on the axis appears high or low depending on the relationship between L and X. That is, when L is less than 0.3 mm, the optical path is below the line connecting the light emitting portion and the lower end of the reflecting surface 2c, and the direct light from the light emitting element 5 does not reach the reflecting surface 2c, and the through hole 7 It is thought that the reflection efficiency was lowered by entering the inside.

  Further, when the optical path line with L of 0.3 mm or more is above the line connecting the light emitting portion and the lower end of the reflecting surface 2c, that is, when light is not directly incident on the through hole 7, the axial luminous intensity X is 0.1mm. It was found that when the thickness was 0.5 mm, it was remarkably high at 500 mcd or more. This is because the light X emitted from the light-emitting element 5 is wavelength-converted with high efficiency by the phosphor 4 because the distance X between the light-emitting portion and the upper surface of the translucent member 3 becomes an appropriate size. It is considered that the light was released to the outside of the translucent member 3 with high efficiency without being obstructed by the body 4.

  From the above results, the lower end of the reflection surface 2c is located on or below the optical path connecting the light emitting section and the corner between the upper surface 2d and the side surface of the mounting section 2b, and the translucent member. It was found that when the distance between the upper surface of 3 and the light emitting portion was 0.1 to 0.5 mm, extremely excellent on-axis luminous intensity was exhibited. In addition, it was confirmed that this sample having a significantly improved on-axis luminous intensity is sufficient in terms of luminance, color rendering and the like.

  It should be noted that the present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the scope of the present invention.

  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 2c and the distance from the upper end of the reflecting surface 2c to the upper surface of the translucent member 3, thereby obtaining better color rendering by providing a complementary color gamut. be able to.

  Further, the lighting device of the present invention is not limited to one in which a plurality of light emitting devices 8 are installed in a predetermined arrangement, but may be one in which one light emitting device 8 is installed in a predetermined arrangement.

It is sectional drawing which shows an example of embodiment about the light-emitting device of this invention. It is sectional drawing which shows the other example of embodiment about the light-emitting device of this invention. It is sectional drawing for demonstrating the space | interval of the upper surface of the translucent member in the light-emitting device of this invention, and a light emission part. It is sectional drawing for demonstrating the space | interval of the upper surface of the translucent member in the light-emitting device of this invention, and a light emission part. It is sectional drawing which shows the light-emitting device of this invention used for the Example. It is sectional drawing which shows the various patterns of the optical path in the light-emitting device of FIG. It is a graph which shows the relationship between the length L of the mounting part in the light-emitting device of this invention, the space | interval X of a translucent member upper surface and a light emission part, and an axial luminous intensity. It is sectional drawing which shows the conventional light-emitting device. It is sectional drawing which shows the other example of embodiment about the light-emitting device of this invention. It is a top view which shows an example of embodiment about the illuminating device of this invention. FIG. 11 is a cross-sectional view of the lighting device of FIG. It is a top view which shows the other example of embodiment about the illuminating device of this invention. FIG. 13 is a cross-sectional view of the illumination device of FIG.

Explanation of symbols

1: Base 2: Reflective member 2a: Side wall 2b: Placement portion 2c: Reflective surface 2d: Upper surface of placement portion 3: Translucent member 4: Phosphor 5: Light emitting element 6: Electrical connection means 7: Through hole 7a: Insulating paste 8: Light emitting device 9: Reflecting jig
10: Light-emitting device drive circuit board

Claims (4)

A flat base, and a convex mounting portion that is bonded to the upper surface of the base and on which the light emitting element is mounted on the upper surface are formed at the center of the upper main surface, A reflecting member formed with a side wall portion that surrounds the portion and whose inner peripheral surface is a reflecting surface that reflects light emitted from the light emitting element, the light emitting element placed on the mounting portion, and the side wall And a translucent member containing a phosphor that converts the wavelength of light emitted from the light emitting element, and the lower end of the reflective surface is the light emitting element. It is located on or below the optical path connecting the light emitting part located at the end of the element and the corner between the upper surface and the side surface of the mounting part, and the translucent member has its upper surface A light emitting device, wherein a distance between the light emitting unit and the light emitting unit is 0.1 to 0.5 mm. The base body is an insulator, and a wiring conductor is formed from the upper surface to the outer surface, and the reflecting member penetrates between the upper and lower main surfaces around the mounting portion and is positioned below the optical path line. The light emitting device according to claim 1, wherein a through hole is formed, and the electrode of the light emitting element and the wiring conductor on the upper surface of the base are electrically connected through the through hole by a wire. . 2. The through-hole is filled with an insulating paste containing insulating light-reflecting particles so as to be flush with the upper main surface of the reflecting member. Item 3. A light emitting device according to Item 2. An illuminating device, wherein the light emitting device according to any one of claims 1 to 3 is installed in a predetermined arrangement.

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