JP4707433B2 - Light emitting device and lighting device - Google Patents

Description

  The present invention relates to a light emitting device in which a light emitting element is accommodated and an illumination device using the same.

  In recent years, it is possible to excite a phosphor contained in a translucent member by visible light or near-ultraviolet light emitted from a light emitting element such as an LED, and convert visible light into a desired wavelength spectrum to emit visible light. Practical use of light emitting devices is progressing. Such light-emitting devices have begun to be used as illumination light sources, and studies have been actively conducted on improving the light emission efficiency and color characteristics.

  A conventional light emitting device is shown in FIG. In the conventional light emitting device, one end portion is led out to a mounting portion 11a on which the light emitting element 13 is mounted, and the other end portion is a side surface of the light emitting element mounting substrate 11. Alternatively, the wiring conductor 11b led out is formed on the lower surface, and the light emitting element 13 is mounted on the mounting portion 11a so as to be electrically connected to the wiring conductor 11b via the conductive member 16.

  Further, the light-emitting element mounting substrate 11 is arranged so that a light-transmitting member 15 containing a phosphor 14 that is excited by light of the light-emitting element 13 and generates fluorescence on the upper surface covers the light-emitting element 13. Thereby, the light from the light-emitting element 13 is wavelength-converted by the phosphor 14 to obtain a light-emitting device that can extract light having a desired wavelength spectrum. In particular, when the light from the light emitting element 13 and the phosphor 14 is in a complementary color relationship, the light emitting device can emit white light.

  The translucent member 15 has a small refractive index difference from the light-emitting element 13 and has a high transmittance with respect to light in the ultraviolet region to the visible region, such as a transparent resin such as silicone resin, epoxy resin, urea resin, or low melting point. The phosphor 14 is contained in a transparent member such as glass or sol-gel glass.

The phosphor 14 emits blue, red, green, etc. fluorescence, for example, an alkaline earth metal aluminate phosphor or an yttrium-aluminum-garnet system activated by at least one element selected from rare earth elements Phosphor, La ₂ O ₂ S: Eu (red light-emitting phosphor), (BaMgAl) ₁₀ O ₁₂ : Eu, Mn (green light-emitting phosphor), (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ C _It consists of phosphors 14 such as _l2 : Eu (blue light-emitting phosphor), and by blending these phosphors 14 in an arbitrary ratio, fluorescence having a desired emission spectrum and color can be output from the light-emitting device. .

The light emitting device 13 emits light by supplying a driving current from an external electric circuit to the light emitting device, and the phosphor 14 that emits visible light is excited by the light emitted from the light emitting device 13 to have a desired wavelength spectrum. The light emitting device emits visible light. In such a light-emitting device, recently, various studies have been made on the arrangement and configuration of the phosphor 14 in the light-emitting device in order to improve the light-emitting efficiency of the light-emitting device and stabilize the color characteristics such as color unevenness and color variation. Yes.
JP 2003-46141 A Japanese Patent Laid-Open No. 2001-148516

  However, the conventional light emitting device has low light use efficiency of the phosphor 14 with respect to the light of the light emitting element 13 necessary for exciting the phosphor 14 contained in the translucent member 15. That is, all of the light from the light emitting element 13 is not used to excite the phosphor 14, and a part of the light is emitted to the outside of the light emitting device while being reflected by the phosphor 14. As a result, it is difficult to make the amount of fluorescence generated from the phosphor sufficient, and there is a problem that the light output emitted from the light emitting device is not sufficient.

Further, powder particles of a plurality of types of phosphors 14 having different specific gravities on the translucent member 15, for example, La ₂ O ₂ S: Eu (red light-emitting phosphor), (BaMgAl) ₁₀ O ₁₂ : Eu, Mn (green light emission) phosphor), (Sr, Ca, Ba , Mg) 10 (PO 4) 6 C l2: Eu ( case of containing the powder of the phosphor 14 composed of blue-emitting phosphor), the upper surface of the light-emitting element mounting substrate 11 While applying an uncured translucent member 15 containing powders of these multiple types of phosphors 14 so as to cover the light emitting element 13, the translucent member 15 is cured by heating or the like. Since the settling speed varies depending on the specific gravity and particle size of each phosphor 14 before curing, a plurality of layers of phosphor 14 having different specific gravities are formed in the translucent member 15. There is. As a result, the amount of fluorescence from the layer of the phosphor 14 arranged near the periphery of the light emitting element 13 is increased, and a light emitting device that emits light having a desired wavelength spectrum to the outside and has little color unevenness and color variation. It had the problem that it was difficult to obtain.

  Further, the powder particles of each phosphor 14 settle down until the translucent member 15 is cured and are deposited so as to cover the periphery of the light emitting element 13. The number of times the emitted light is reflected and scattered by the phosphor 14 is extremely increased, the light is reflected in the light emitting element 13, and the light absorption loss due to the light emitting element 13 is remarkably increased. When the light propagating to the body 14 is extremely lowered, the amount of the phosphor 14 excited by the light of the light emitting element 13 may be reduced. As a result, the light emitting device has a problem that the light output is reduced by the sedimentation of the phosphor.

  Furthermore, the phosphor 14 is oxidized by moisture intrusion from the external environment, so that the phosphor 14 is not excited to a desired excited state and changes to absorb light, and the luminous efficiency is deteriorated. In some cases, the light emitting device cannot emit stable high-power light for a long period of time.

  Accordingly, the present invention has been devised in view of the above-described conventional problems, and the object of the present invention is to improve the light use efficiency by the phosphor excited by the light emitted from the light emitting element, and to increase the fluorescence generated from the phosphor. The light output of the light emitting device is improved by increasing the amount of light. It is another object of the present invention to provide a light emitting device and an illuminating device with high light output that suppress the occurrence of color unevenness and color variation of light emitted outside the light emitting device and are excellent in long-term reliability.

The light-emitting device of the present invention includes a base , a light-emitting element mounted on the top surface of the base, a translucent member that is positioned on the top surface of the base and covers the light-emitting element, and a refractive index of the translucent member Ri Na a number of phosphors are contained inside as well as have a higher refractive index than, and a granular material dispersed in the translucent member, the air bubbles are dispersed in particulate shaped body Features.

  The illuminating device of the present invention is characterized by using the light emitting device of the present invention as a light source.

According to the light emitting device of the present invention, the substrate and a light emitting element mounted on the upper surface of the base body, and the translucent member covering the light emitting element is positioned on an upper surface of the substrate, the light-transmissive member refractive index Ri Na are contained a number of phosphors therein while have a greater refractive index than a granular material dispersed in the translucent member, the bubbles are dispersed in particulate shaped body . Thereby , the light from the light emitting element can enter the granular body without being totally reflected at the interface between the granular body and the translucent member, even if the incident angle to the granular body is increased to some extent. The phosphor in the body can be excited. In addition, light from the light emitting element that is incident on the granular material and reflected by the fluorescent material without exciting the fluorescent material is reflected at the interface between the granular material having a refractive index larger than that of the light transmitting member and the light transmitting member. It is easy to be totally reflected inside the granular material, and the totally reflected light easily excites the fluorescent material inside the granular material and easily generates fluorescence. As a result, it is possible to improve the light use efficiency from the light emitting element necessary for exciting the phosphor, and to improve the light output of the light emitting device. Further, since the bubbles are dispersed in the granular material, light is diffused in the granular material, so that the light easily hits the phosphor.

  Furthermore, the phosphor is protected by the translucent member and the granular material, can improve the water resistance, and can suppress the phosphor from being deteriorated by moisture.

  In addition, since the lighting device of the present invention uses the light-emitting device of the present invention as a light source, it has lower power consumption and longer life than the conventional lighting device using discharge, and stable radiant light intensity over a long period of time. In addition, it is possible to irradiate light at a radiated light angle (light distribution), and to reduce unevenness of color unevenness and illuminance distribution on the irradiated surface.

  The light-emitting device and lighting 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 the light-emitting device of the present invention, and FIG. 2 is a cross-sectional view showing another example of the embodiment of the light-emitting device of the present invention. 1 and 2, reference numeral 1 denotes a base for mounting a light emitting element, 3 denotes a light emitting element mounted on the upper surface of the base 1, and 4 denotes a transparent member having a refractive index larger than that of the translucent member 5. 5 is a translucent member that covers the light emitting element 3, and 2 is a frame that is attached to the upper surface of the substrate 1 so as to surround the mounting portion 1 a of the light emitting element 3. is there. Note that 1b is a wiring conductor having one end formed on the upper surface and connected to the electrode of the light emitting element 3 and the other end led to the side surface or the lower surface of the base 1, and 6 is an electrode of the light emitting element 3 and one end of the wiring conductor 1b. The conductive member which electrically connects is connected.

  The light emitting device of the present invention is configured by mounting the light emitting element 3 on the mounting portion 1 a on the upper surface of the base 1 and covering the light emitting element 3 with a translucent member 5. In the translucent member 5, a large number of phosphors 4 a are used as a wavelength conversion member that emits fluorescence having a wavelength different from that of the light emitted from the light emitting element 3 when excited by the light emitted from the light emitting element 3. The granular material 4 dispersed in the transparent member having a refractive index larger than the refractive index is contained.

  The substrate 1 is an insulator made of an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, ceramics such as glass ceramics, or a resin such as epoxy resin, and supports the light emitting element 3. It functions as a member, and the light emitting element 3 is mounted on the upper surface thereof.

  Further, when the substrate 1 is made of ceramics, tungsten (W), molybdenum (Mo), manganese (Mn), Mo—Mn, copper (Cu), etc. are used to electrically connect the inside and outside of the light emitting device. A wiring conductor 1b made of metal is formed. Then, the light emitting element 3 is electrically connected to one end of the wiring conductor 1b on the upper surface of the base 1, and the external electric circuit board is electrically connected to the other end of the wiring conductor 1b led out to the side surface or the lower surface of the base 1. Thus, the external electric circuit board and the light emitting element 3 can be electrically connected. Such a wiring conductor 1b is formed using a known metallizing method, plating method or the like.

  The wiring conductor 1b is preferably coated with a metal layer having excellent corrosion resistance, such as a Ni layer having a thickness of 0.5 to 9 μm or an Au layer having a thickness of 0.5 to 5 μm, on the exposed surface of the substrate 1. It is possible to effectively prevent the wiring conductor 1b from being oxidatively corroded and to strengthen the bonding with the light emitting element 3 by the conductive member 6 such as solder.

  In addition, the substrate 1 suppresses the transmission of light emitted from the light emitting element 3 on the upper surface to the lower surface of the substrate 1, and the wiring conductor 1b is electrically connected to efficiently reflect the light above the substrate 1. It is preferable that a metal layer such as aluminum (Al), silver (Ag), gold (Au), platinum (Pt), or Cu is formed on the upper surface of the substrate 1 by vapor deposition or plating so as not to cause a short circuit.

  The light emitting element 3 may have any peak wavelength of energy to be emitted from the ultraviolet region to the infrared region. However, from the viewpoint of emitting white light and light of various colors from the light emitting device with good visibility, the light emitting element 3 has a peak wavelength of 300 to 500 nm. It is preferable that the device emits light from near ultraviolet light to blue light. For example, a buffer layer composed of gallium (Ga) -nitrogen (N), Al-Ga-N, indium (In) -GaN, etc., an N-type layer, a light-emitting layer, and a P-type layer are sequentially stacked on a sapphire substrate. A gallium nitride compound semiconductor or a silicon carbide (SiC) compound semiconductor is used.

  In the light emitting element 3, the electrodes are made of solder bumps using solder or solder such as Au-tin (Sn), Sn-Ag, Sn-Ag-Cu or Sn-lead (Pb), or Au or Ag. It is electrically connected to the wiring conductor 1b by flip-chip mounting through connection means made of metal bumps using metal. For example, the conductive member 6 made of a paste material such as Au-Sn or Pb-Sn or Ag paste is placed on the wiring conductor 1b by using a dispenser or the like, and the electrode and the conductive member of the light emitting element 3 are placed. The light emitting element 3 is mounted so that the upper surface of 6 is in contact, and then the whole is heated at about 250 ° C. to 350 ° C., so that the electrode of the light emitting element 3 and the wiring conductor 1 b are electrically connected by the conductive member 6. And the like.

  The translucent member 5 has a small refractive index difference from the light emitting element 3 and has a high transmittance with respect to light in the ultraviolet region to the visible region, such as a transparent resin such as a silicone resin, an epoxy resin, or a urea resin, or a low melting point. It consists of transparent glass etc., such as glass and sol-gel glass. The translucent member 5 may be appropriately selected in consideration of the material of the base 1, the thermal expansion coefficient, and the like, and is not particularly limited. In addition, since the difference in refractive index between the light emitting element 3 and the translucent member 5 is small, it is possible to effectively suppress the occurrence of light reflection loss at the interface between the light emitting element 3 and the translucent member 5. Further, it is preferable to select in consideration of the refractive index.

  Then, by applying a light-curing member 5 so as to cover the light-emitting element 3 on the upper surface of the substrate 1 with an injector such as a dispenser, and then thermally curing it, the desired radiation intensity can be efficiently transferred to the outside of the light-emitting device. Thus, a light emitting device that emits light with a distribution of radiation angles can be manufactured.

Translucent member 5 is partly, for example, the upper surface near or light-transmitting member 5, or the whole, the phosphor is excited by the light emitting element 3 consisting of fluorescent material or a fluorescent pigment that Hassu fluorescence A granular material 4 containing 4a in a transparent member is dispersed. Such a phosphor 4a emits energy having a wavelength in the visible light region when electrons in the phosphor 4 are excited by light emitted from the light emitting element 3 and the excited electrons return to the ground state. Fluorescence of blue, red, green, etc., such as alkaline earth aluminate phosphors and yttrium-aluminum-garnet phosphors activated with at least one element selected from rare earth elements Consists of substances and fluorescent pigments. By blending these phosphors 4a at an arbitrary ratio, fluorescence having a desired emission spectrum and color can be emitted. And the granular material 4 which contains these fluorescent substance 4a is disperse | distributed to a part, such as the upper part of the translucent member 5, and the whole translucent member 5. FIG. Alternatively, another translucent member 5 in which the granular body 4 is uniformly dispersed in the translucent member 5 may be disposed on the upper surface or above the translucent member 5 in which the granular body 4 is not dispersed. .

  The granular material 4 of the light emitting device of the present invention is a transparent member having a refractive index larger than the refractive index of the translucent member 5, such as silicone resin (refractive index: 1.4 to 1.53), epoxy resin (refractive index: 1.52 to 1.54), Transparent members such as urea resin (refractive index: 1.45 to 1.5), transparent members such as low melting glass (refractive index: 1.5 to 1.6), sol-gel glass (refractive index: 1.45 to 1.55), etc. Each of the phosphors 4a is excited by light from the light-emitting element 3 and generates desired fluorescence such as red light, green light, and blue light. In addition, the granular material 4 may contain a plurality of types of phosphors 4a that emit a desired fluorescent color, or may contain a single type of phosphor 4a as long as it is a single-color fluorescent color.

  Such a granular material 4 improves the use efficiency of light from the light emitting element 3 necessary for exciting the phosphor 4a and increases the amount of fluorescence generated from the phosphor 4a, thereby increasing the light output of the light emitting device. Can be improved.

That is, since the refractive index of the granular body 4 is larger than the refractive index of the translucent member 5, the light from the light emitting element 3 enters the granular body 4 at the interface between the granular body 4 and the translucent member 5. Even if the angle increases to some extent, it can enter the granular material 4 without being totally reflected, and the phosphor 4a in the granular material 4 can be excited. Further, a part of the light from the light emitting element 3 that has entered the granular body 4 is reflected by the phosphor without exciting the phosphor 4 a, but the light-transmissive member 5 having a smaller refractive index than the granular body 4 Light having a large incident angle at the interface is confined in the granular material 4 while being totally reflected, and strikes the phosphor 4a to excite the phosphor 4a. Thus, the light from the light emitting element 3 reflected by the phosphor 4a without exciting the phosphor 4a strikes the phosphor 4a again while repeating total reflection at the interface between the granular material 4 and the translucent member 5. probability increases, thereby generating fluorescence from the phosphor 4a. As a result, by using the granular material 4, it is possible to improve the light use efficiency from the light-emitting element 3 necessary for exciting the phosphor 4 a, increase the fluorescence generated from the phosphor 4 a, and the light-emitting device. Can improve the light output.

  In addition, when the refractive index of the transparent member containing fluorescent substance 4a is smaller than the refractive index of the translucent member 5, it is large incident from the translucent member 5 side with respect to the interface of the translucent member 5 and the granular material 4. The light from the light emitting element 3 incident at the corner is totally reflected. As a result, light from the light emitting element 3 incident on the granular body 4 from the translucent member 5 is reduced, and fluorescence generated from the phosphor 4a excited by the light from the light emitting element 3 is reduced. Furthermore, the light from the light emitting element 3 reflected by the phosphor 4a without exciting the phosphor 4a is totally reflected even at a certain large incident angle at the interface between the granular material 4 and the translucent member 5. Instead, the light is transmitted to the translucent member 5 side and emitted to the outside of the light emitting device. As a result, the light confinement effect of the granular body 4 is reduced, and the light utilization efficiency from the light emitting element 3 necessary for exciting the phosphor cannot be improved.

  Moreover, the granular material 4 can increase the buoyancy of the granular material 4 in the translucent member 5 by increasing the volume. That is, if the density of the translucent member 5 is ρ, the acceleration of gravity is g, and the volume of the granular body 4 is v, the buoyancy generated in the granular body 4 in the translucent member 5 is ρgv. By increasing the volume of, a buoyancy that is significantly greater than the buoyancy of the powdered phosphor 4a alone can be generated. And when the specific gravity of the granular body 4 is the same or smaller than the specific gravity of the translucent member 5, by using this buoyancy, sedimentation of the granular body 4 can be suppressed in the translucent member 5, and the granular body 4 can be easily dispersed in the translucent member 5. Alternatively, the granular material 4 can be accumulated near the upper surface of the translucent member 5, and the granular material 4 can be prevented from being deposited near the light emitting element 3. And it can suppress that the light emitted from the light emitting element 3 is light-shielded by the one part granular material 4 deposited in the light emitting element 3 vicinity.

  In addition, when the specific gravity of the granular material 4 containing the phosphor 4a in the transparent member is larger than the specific gravity of the translucent member 5, the specific gravity can be increased by dispersing small bubbles such as air in the granular material 4. Adjust it. Such a bubble has a small refractive index and diffuses light in the granular material 4, so that the light easily hits the phosphor 4a.

  As a result, it is possible to suppress degradation of the light extraction efficiency of the light emitting element 3 due to the sedimentation and deposition of the granular material 4 around the light emitting element 3, and to directly transmit a plurality of types of phosphor powders having different specific gravities. When dispersed in the light-sensitive member 5, the phosphor powders settle at different speeds, thereby preventing a plurality of types of phosphor powders from forming a multi-layered layer structure. As a result, it is possible to suppress the occurrence of color unevenness and color variation in the light emitted from the light emitting device.

  Furthermore, since a plurality of phosphors 4a are previously dispersed and contained in each granular material 4 at a desired blending ratio, and this granular material 4 is dispersed in the translucent member 5, one kind of the plurality of phosphors 4a is included. Is not unevenly distributed in the translucent member 5, and it is possible to suppress the occurrence of color unevenness and color variation in the light emitted from the light emitting device.

  The granular body 4 is formed into a spherical shape by placing an uncured transparent member containing the phosphor 4a dispersed therein and placing the uncured transparent member on the heater block individually in a minute solid state using a dispenser or the like and heating them. The Or the granular material 4 may be formed in a granular form by grind | pulverizing the block-shaped solid member which disperse | distributed fluorescent substance 4a in translucent glass, resin, etc. FIG. Further, the granular body 4 may be formed into a fine three-dimensional granular body 4 by forming a transparent member in which the phosphor 4a is dispersed into a plate shape and cutting it into a desired shape. Furthermore, the granular material 4 may be produced by molding a transparent member containing a phosphor into a minute shape using a molding die. In addition, since fluorescent substance 4a is coat | covered with glass, since glass has small water permeability, it can prevent that fluorescent substance 4a absorbs moisture and the luminous efficiency of fluorescent substance 4a deteriorates.

  Moreover, it is preferable that the granular material 4 contains the powder-form scattering member (not shown) which consists of a metal oxide inside. That is, the scattering member scatters the light incident on the granular material 4, thereby increasing the amount of light hitting the phosphor 4 a and improving the light output of the light emitting device. In addition, the scattering member is suitable in that the light-reflective metal oxide powder such as alumina, zirconia, titania, silica, magnesia, zinc oxide and the like can scatter light with low loss. It is.

  Moreover, it is preferable to disperse | distribute the granular material 4 in the translucent member 5 by making a diameter into 0.1 mm thru | or 2 mm. As a result, the granular material 4 is sufficiently dispersed without being settled in the translucent member 5, and is radiated to the outside of the light emitting device without being wavelength-converted by the granular material 4 in which the light of the light emitting element 3 is dispersed. It can be suppressed. That is, when the diameter of the granular material 4 is 0.1 mm or less, the buoyancy to the granular material 4 by the translucent member 5 becomes small, and it becomes difficult to contain sufficient phosphor 4a in the granular material 4. Thereby, the light from the light emitting element 3 is taken in by the granular material 4, and is not fully converted into fluorescence, and the light emission output of the light emitting device tends to decrease. Further, when the diameter of the granular material 4 is larger than 2 mm, the dispersion density of the granular material 4 in the translucent member 5 is reduced, and a gap generated between the adjacent granular materials 4 is increased, so that the granular material 4 is incident on the granular material 4. Therefore, more light is emitted directly to the outside of the light emitting device, and the light output of the light emitting device is reduced.

  As shown in FIG. 2, the light emitting device of the present invention is attached to the upper surface of the base 1 so as to surround the mounting portion 1a, and reflects the light from the light emitting element 3 and the fluorescence from the phosphor. The frame body 2 having 2a is replaced with a metal brazing material such as Ag-Cu, Pb-Sn, Au-Sn, Au-silicon (Si), Sn-Ag-Cu, solder, or a resin bonding agent such as silicone or epoxy. It is good also as what was attached with joining materials, such as.

  The bonding material may be appropriately selected in consideration of the material of the base 1 and the frame 2, the thermal expansion coefficient, and the like, and is not particularly limited. In addition, when high reliability of bonding between the base body 1 and the frame body 2 is required, it is preferable to bond with a metal brazing material or solder.

  The frame body 2 may be formed integrally with the base body 1. For example, when the base body 1 and the frame body 2 are made of ceramics, a ceramic green sheet to be the base body 1 and a ceramic green sheet to be the frame body 2 are combined. It can be formed by stacking and firing at the same time.

  The frame 2 has a light reflecting surface 2a whose inner peripheral surface efficiently reflects the light of the light emitting element 3. With this configuration, the light reflecting surface 2a is formed so as to surround the light emitting element 3 around the light emitting element 3, so that the light emitted from the light emitting element 3 is efficiently above (in the output direction) the light emitting device. In addition to being reflected, the absorption and transmission of light by the substrate 1 are effectively suppressed, so that the emitted light intensity and luminance can be significantly improved.

  The light reflecting surface 2a includes a frame 2 made of a highly reflective metal such as Al, Ag, Au, Pt, titanium (Ti), chromium (Cr), Cu, ceramics such as white, or resin such as white. It is formed by machining by cutting or mold forming. Alternatively, the light reflecting surface 2a may be formed on the inner peripheral surface of the frame 2 by forming a metal thin film such as Al, Ag, or Au by plating or vapor deposition. In addition, when the light reflecting surface 2a is made of a metal that is easily discolored by oxidation such as Ag or Cu, an inorganic substance such as a low-melting glass or sol-gel glass having excellent transmittance from the ultraviolet light region to the visible light region, It is better to deposit organic substances such as silicone resin and epoxy resin. As a result, the corrosion resistance, chemical resistance, and weather resistance of the light reflecting surface 2a are improved.

  The light reflecting surface 2a is preferably inclined so as to spread outward as it goes upward. Thereby, the light emitted from the light emitting element 3 can be efficiently reflected upward of the light emitting device. The arithmetic average roughness Ra of the light reflecting surface 2a is preferably 4 μm or less. As a result, the light loss of the light emitting element 3 can be satisfactorily reflected above the light emitting device with the light loss reduced. When Ra exceeds 4 μm, it becomes difficult to reflect the light of the light emitting element 3 by the light reflecting surface 2a and to emit the light upward from the light emitting device, and to easily diffuse the light inside the light emitting device. As a result, the propagation loss of light inside the light emitting device tends to increase, and it becomes difficult to emit light efficiently outside the light emitting device at a desired radiation angle.

  Further, when the arithmetic mean roughness Ra is less than 0.004 μm, it is difficult to form such a surface stably and efficiently, and the product cost tends to increase. Accordingly, the arithmetic average roughness of the light reflecting surface 2a is more preferably 0.004 to 4 μm.

  In order to set the Ra of the light reflecting surface 2a within the above range, it may be formed by a conventionally known electrolytic polishing process, chemical polishing process or cutting polishing process. Further, a method of forming by transfer processing using the surface accuracy of the mold may be used.

  The light reflecting surface 2a may be flat (straight) as shown in FIG. 1, or may be arcuate (curved). In the case of an arc shape, the light from the light emitting element 3 can be concentrated by reflection, and highly directional light can be uniformly emitted to the outside.

  Further, the light emitting device of the present invention can be obtained by using one light source as a light source, or a plurality of, for example, a circular or polygonal light emitting device group composed of a lattice shape, a staggered shape, a radial shape, or a plurality of light emitting devices. Can be used as a light source that is arranged so as to have a predetermined arrangement such as a concentric arrangement of a plurality of groups. As a result, the lighting device of the present invention can have lower power consumption and longer life than the conventional lighting device using discharge when utilizing light emitted from the light emitting element 3 made of semiconductor, and further generates heat. A small and small lighting device can be obtained. As a result, since the heat generation is small, the fluctuation of the band gap of the light-emitting element 3 due to heat is suppressed, so that the fluctuation of the center wavelength of light generated from the light-emitting element 3 can be suppressed. Variation in the conversion efficiency of the phosphor 4a depending on the light is suppressed, the light intensity of the fluorescence generated from the granular material 4 is stabilized, and the variation in the mixing ratio of the light from the light emitting element 3 and the phosphor 4a output from the light emitting device By suppressing the light, it is possible to irradiate light with a stable radiated light intensity and a radiated light angle (light distribution distribution) over a long period of time, and to make an illumination device with less uneven color and uneven illuminance distribution on the irradiated surface be able to.

  In addition, the light-emitting device of the present invention is used as a light source, a light-emitting device mounting substrate on which the light-emitting device is mounted is installed in a predetermined arrangement, and a reflector such as a reflector optically designed in an arbitrary shape around these light-emitting devices, By installing an optical lens, a light diffusing plate, etc., an illumination device capable of emitting light having an arbitrary light distribution can be obtained.

The light emitting equipment mounting substrate includes a power supply wiring for supplying electric power to the light emitting device to fix the light-emitting device. For example, a light emitting device driving circuit board formed by forming a wiring conductor on an insulating substrate can be used. The reflector has a light reflecting surface for satisfactorily irradiating light emitted from the light emitting device in a desired direction, and is formed by the same material and manufacturing method as the reflecting member 2 used in the light emitting device of the present invention. Is done.

  For example, a plurality of light emitting devices 101 of the present invention are arranged in a plurality of rows on the light emitting device driving circuit board 102 as shown in the plan view and the sectional view shown in FIGS. In the case of an illuminating device in which the optically designed reflector 103 is installed, a so-called staggered arrangement in which the light emitting devices 101 in adjacent rows are arranged between a plurality of light emitting devices 101 arranged in a row is used. Is preferred. That is, when the light emitting devices 101 are arranged in a vertical and horizontal grid, the glare is strengthened by arranging the light emitting devices 101 as light sources on a straight line, and such a lighting device enters human vision. However, the staggered pattern makes the light intensity due to the light contrast in the light emitting area where the light emitting device is located and the non-light emitting area where the light emitting device is not located. Since the difference (strength) can be reduced and the perceived emission intensity can be relaxed, glare can be suppressed, and discomfort to the human eye and damage to the eye can be reduced. Furthermore, compared to the case where the light emitting devices 101 are not arranged in a staggered manner, the distance between the adjacent light emitting devices 101 is increased, so that thermal interference between the adjacent light emitting devices 101 is effectively suppressed, and the light emitting device in which the light emitting devices 101 are mounted. Heat accumulation in the device drive circuit board 102 is suppressed, and heat is efficiently dissipated outside the light emitting device 101. As a result, it is possible to manufacture a long-life lighting device having stable optical characteristics over a long period of time with less obstacles to human eyes.

  Further, the lighting device is a concentric arrangement of a circular or polygonal light emitting device 101 group composed of a plurality of light emitting devices 101 on the light emitting device drive circuit board 102 as shown in the plan view and the sectional view shown in FIGS. In the case of a plurality of illuminating devices arranged in a group, it is preferable that the number of light emitting devices 101 arranged in one circular or polygonal light emitting device 101 group be increased from the center side of the illuminating device toward the outer peripheral side. Thereby, it is possible to arrange more light emitting devices 101 while maintaining an appropriate interval between the light emitting devices 101, and it is possible to further improve the illuminance of the lighting device. In addition, the density of the light emitting device 101 in the central portion of the lighting device can be reduced to suppress heat accumulation in the central portion of the light emitting device driving circuit board 102. Therefore, the temperature distribution in the light emitting device driving circuit board 102 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 101 can be suppressed. As a result, the light-emitting device 101 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, and street lamp lighting fixtures that are 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 , Electronic bulletin boards and the like, backlights such as dimmers, automatic flashers, displays, moving image devices, ornaments, illuminated switches, optical sensors, medical lights, in-vehicle lights, and the like.

  It should be noted that the present invention is not limited to the above-described embodiment, and various modifications are not hindered without departing from the gist of the present invention. For example, an optical lens for condensing and diffusing the light emitted from the light emitting device to the upper surface of the frame body 2 or a flat light-transmitting lid body may be joined by soldering or a resin bonding agent. In addition to the light emitting device 101 that can extract light at a radiation angle, the water resistance of the light emitting device 101 is improved and long-term reliability is improved.

It is sectional drawing which shows an example of embodiment of the light-emitting device of this invention. It is sectional drawing which shows the other example of embodiment of the light-emitting device of this invention. 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. It is sectional drawing of the conventional light-emitting device.

Explanation of symbols

1: Base body 2: Frame body 2a: Light reflecting surface 3: Light emitting element 4: Granular body 4a: Phosphor 5: Translucent member

Claims (4)

A substrate ;
A light emitting element mounted on the upper surface of the base body,
And the translucent member covering the light emitting element is positioned on an upper surface of the substrate,
Ri Na a number of phosphors are contained inside as well as have a refractive index greater than the refractive index of the light-transmitting member, and a granular material dispersed in the light-transmitting member,
A light emitting device characterized in that bubbles are dispersed in the granular material . 2. The light emitting device according to claim 1, wherein the number of the granular materials is greater in the vicinity of the upper surface of the translucent member than in the vicinity of the light emitting element of the translucent member . 2. The light emitting device according to claim 1, wherein the granular material contains a powdery scattering member made of a metal oxide. 4. A lighting device using the light emitting device according to claim 1 as a light source.

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