JP5196711B2 - LIGHT EMITTING DEVICE AND LIGHTING DEVICE USING THE SAME - Google Patents

Description

  The present invention relates to a light-emitting device using a light-emitting element and an illumination device using the same, and more specifically, a light-emitting device using a plurality of types of phosphors that emit fluorescence when excited by light emitted from a semiconductor light-emitting element or the like. It is related with the illuminating device using.

  Conventionally, a plurality of types of phosphors that emit fluorescence in the visible region such as red, green, blue, yellow, etc., using light such as near-ultraviolet light and blue light emitted from light-emitting elements such as light-emitting diodes (LEDs) as excitation light. A light-emitting device that emits light having a desired wavelength spectrum is known. An example of a conventional light emitting device is shown in FIG. In FIG. 14, 11 is a base, 12 is a frame, 12a is a light reflecting surface formed on the inner peripheral surface of the frame 12, 13 is a light emitting element, 14 is a wavelength conversion member containing a phosphor 15 in a transparent member, Reference numeral 16 denotes a conductive member.

  As shown in FIG. 14, the conventional light emitting device has a mounting portion 11a for mounting the light emitting element 13 on the upper main surface, and electrically connects the inside and outside of the light emitting device from the mounting portion 11a and its periphery. A base body 11 made of an insulator having a wiring conductor 11b formed thereon and an outer peripheral portion of the upper main surface of the base body 11 are bonded and fixed so as to surround the mounting portion 11a, and a through hole having an upper opening larger than the lower opening is formed. In addition, the frame 12 has an inner peripheral surface that is a light reflecting surface 12a that reflects light emitted from the light-emitting element 13 and the phosphor 15, and the mounting portion 11a is electrically connected to the wiring conductor 11b via the conductive member 16. Light-emitting elements 13 connected to each other, and a wavelength conversion member 14 formed so as to cover the light-emitting elements 13. The wavelength conversion member 14 is formed by excitation light emitted from the light-emitting elements 13 in a transparent member. The phosphor 15 that is excited and emits fluorescence is included.

Then, the phosphor 15 contained in the wavelength conversion member 14 is, for example, light emitted from the light emitting element 13 (hereinafter referred to as a light emitting element from the light emitting element) in order to obtain fluorescence of a desired visible region wavelength such as red, green, blue, and yellow. A first phosphor 15a that emits fluorescence with a first visible region wavelength and a second phosphor that emits fluorescence with a second visible region wavelength. It consists of a plurality of phosphors 15a and 15b with 15b. The plurality of phosphors 15a and 15b each have an absorptance of light emitted from the light-emitting element 13 and excitation fluorescence depending on the first and second phosphors 15a and 15b that emit fluorescence having a desired visible region wavelength. Properties such as strength are different. Therefore, in order to adjust the intensity of the obtained fluorescence, for example, the wavelength conversion member 14 having a desired fluorescence intensity distribution is obtained by adjusting the blending ratio of the phosphors 15a and 15b contained in the wavelength conversion member 14.
JP 2004-253747 A JP 2004-179644 A JP 2000-31531 A

  However, in the conventional light emitting device, the wavelength conversion member 14 is mixed with the first phosphor 15a having a low absorption rate of light emitted from the light emitting element 13 and the second phosphor 15b having a high absorption rate. In this case, since the amount of excitation light absorbed by the second phosphor 15b having a high absorption rate with respect to the excitation light from the light emitting element 13 is increased, sufficient excitation is performed for the first phosphor 15a having a low absorption rate. The light will not spread. As a result, the quantum efficiency with respect to the excitation light of the second phosphor 15b included in the wavelength conversion member 14 (the fluorescence emitted from the second phosphor 15b with respect to the number of photons of the excitation light irradiated to the second phosphor 15b). Although the amount of fluorescence emitted from the second phosphor 15b increases in accordance with the ratio of the number of photons), the amount of excitation light to be wavelength-converted by absorption by the first phosphor 15a decreases. The amount of fluorescence emitted by the first phosphor 15a corresponding to the quantum efficiency of the first phosphor 15a decreases.

  That is, when the first phosphor 15a and the second phosphor 15b are mixed and contained in the wavelength conversion member 14, the first phosphor 15b having a high absorptance can obtain sufficient fluorescence, but the first phosphor 15a and the second phosphor 15b are mixed. Since the excitation light to be absorbed by the phosphor 15a is absorbed by the second phosphor 15b and decreases, the fluorescence by the first phosphor 15a is remarkably reduced.

  Therefore, in order to make the fluorescence emitted by the first phosphor 15a necessary, it is necessary to increase the blending ratio of the first phosphor 15a contained in the wavelength conversion member 14, and so on. If the blending ratio of the phosphors 15a is increased, for example, the amount of fluorescence emitted from the first phosphor 15a increases, but the increased first phosphor 15a itself becomes an obstacle to light propagation, and the wavelength conversion member 14 has an increased amount of fluorescence. Light absorption loss also increases. Accordingly, the wavelength of the excitation light emitted from the light emitting element 13 is converted by the phosphor 15 in the wavelength conversion member 14 to emit fluorescence to the outside of the light emitting device, in other words, the wavelength conversion efficiency of the wavelength conversion member 14 (wavelength conversion member A new problem arises that the ratio of the light energy of the fluorescence emitted from the wavelength conversion member 14 to the light energy of the excitation light irradiated on the light 14 becomes worse. As a result, the light emission efficiency of the light emitting device (indicating the ratio of the total luminous flux emitted from the light emitting device to the power of energy input to the light emitting element), which depends on the wavelength conversion efficiency of the wavelength conversion member 14, is not improved. Had a point.

  When the first and second phosphors 15a and 15b are mixed with the wavelength conversion member 14, the first and second phosphors are dispersed depending on the dispersion state of the first and second phosphors 15a and 15b in the wavelength conversion member 14. The amount of excitation light that irradiates the phosphors 15a and 15b varies. That is, the excitation light emitted from the light emitting element 13 is absorbed by the first and second phosphors 15a and 15b at an equal ratio in a portion where the wavelength conversion member 14 is present, or the first fluorescence is emitted in other portions. Most of the light is absorbed by the body 15a, and most of the light is absorbed by the second phosphor 15b. As a result, there is a variation in the ratio of the respective fluorescence emitted from the first phosphor 15a and the second phosphor 15b, and there is a problem that color unevenness and variation occur on the light emitting surface and the irradiation surface of the light emitting device. Had a point.

  Further, when the amount of the phosphor 15 is not sufficient, part of the light from the light emitting element 13 is reflected by the respective phosphors 15a and 15b without exciting the first and second phosphors 15a and 15b. Or directly to the outside of the light emitting device. Therefore, for example, when the light emitted from the light-emitting element 13 has a wavelength spectrum from the ultraviolet region to the near-ultraviolet region, light having high energy at this short wavelength is emitted to the outside of the light emitting device, and light deterioration outside the light emitting device is caused. There is a problem in that it may adversely affect substances that are likely to occur.

  Accordingly, the present invention has been devised in view of the above-described conventional problems, and its object is to improve the light emission efficiency of the light emitting device by improving the wavelength conversion efficiency of the wavelength conversion member provided in the light emitting device. An object of the present invention is to provide a light emitting device capable of suppressing color variation and color unevenness of output light of a light emitting device and reducing light emitted from a light emitting element emitted to the outside of the light emitting device, and an illumination device using the same. is there.

The light emitting device of the present invention is mounted a base member, the upper surface of the base body, a light emitting element for emitting a first light, provided so as to cover the light emitting element, the second being excited by the first light of the first wavelength converter containing a first phosphor transparent member for generating light, provided so as to cover the first wavelength converter, the third is excited by the first light And a second wavelength conversion unit containing a second phosphor that generates light and has a higher absorption rate of the first light than the first phosphor.

In the light emitting device of the present invention, preferably, the first wavelength conversion unit and the second wavelength conversion unit are configured to cover the first wavelength conversion unit and to be covered by the second wavelength conversion unit. It further has a translucent member provided between the two.

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

  The light-emitting device of the present invention is provided so as to cover the light-emitting element, and is provided so as to cover the first wavelength converter containing the first phosphor and the first wavelength converter, and the first phosphor A first wavelength converter having a second phosphor containing a second phosphor having a higher absorption rate of light emitted from the light-emitting element, so that the first absorptivity of light from the light-emitting element is lower than that of the second phosphor. The first wavelength conversion unit containing the phosphor is irradiated with light emitted from the light emitting element prior to the second wavelength conversion unit containing the second phosphor having a high light absorption rate. Since the amount of excitation light directly absorbed by the first phosphor from the device is stably increased, the amount of fluorescence emitted by the first phosphor is also stabilized according to the quantum efficiency of the first phosphor. Can be increased.

  Further, the amount of the second phosphor irradiated by the light from the light emitting element that is not absorbed by the first phosphor or the light from the light emitting element diffused by the first phosphor is the second amount. Since it increases in the surface direction of the wavelength conversion part, the amount of fluorescence emitted by the second phosphor can also be improved according to the quantum efficiency of the second phosphor. That is, since the excitation light emitted from the light emitting element is reflected and diffused by the first phosphor, and the excitation light from the diffused light emitting element irradiates the second phosphor uniformly, the excitation from the light emitting element Since the light does not concentrate on a part of the second wavelength conversion unit, and as a result, the amount of the second phosphor excited by the excitation light increases, the wavelength conversion efficiency of the second wavelength conversion unit is increased. The light emission efficiency of the light emitting device is improved.

  Furthermore, since the amount of excitation light from the light emitting element that irradiates the first and second phosphors is constant, the amount of fluorescence emitted from the first and second phosphors is stabilized. Furthermore, the fluorescence emitted from the first and second phosphors is diffused over the planes of the first and second wavelength converters and emitted upward, so that the diffused first and second phosphors are emitted. Fluorescence from the phosphors is mixed and emitted from the light emitting surface of the light emitting device. As a result, the light emitting device has less color unevenness and color variation on the light emitting surface and the irradiated surface.

  Further, the first phosphor and the second phosphor are arranged independently, and the second phosphor having a high absorption rate for the excitation light is arranged on the upper side of the light emitting device, thereby converting the wavelength. Since the efficiency is improved, high-energy light from the light-emitting element is less emitted to the outside of the light-emitting device, and adverse effects on substances that easily cause light deterioration outside the light-emitting device can be reduced. .

  Further, according to the illumination device of the present invention, since the light emitting device of the present invention is used as a light source, the light emitting devices having excellent wavelength conversion efficiency and less intensity unevenness are arranged in a predetermined arrangement, and the light emitting devices of these light emitting devices are arranged. By installing a reflector, an optical lens, a light diffusing plate, or the like that is optically designed in a required shape in the surroundings, an illumination device that emits light having a required light distribution can be obtained.

  The light emitting device of the present invention will be described in detail below. 1 to 9 are cross-sectional views seen from the front showing various examples of embodiments of the light emitting device of the present invention. In these drawings, reference numeral 1 denotes a substrate on which the light-emitting element 3 is mounted, 3 denotes a light-emitting element, 4 denotes a wavelength conversion member including a first wavelength conversion unit 4a and a second wavelength conversion unit 4b, and 4a denotes A first wavelength conversion unit 4b containing a first phosphor 5a that is excited by light emitted from the light emitting element 3 on the transparent member and generates fluorescence is provided so as to cover the first wavelength conversion unit 4a. This is a second wavelength conversion section containing a second phosphor 5b having a higher absorption rate of light emitted from the light emitting element 3 than the first phosphor 5a, and these constitute a light emitting device mainly. Reference numeral 1b denotes a line conductor formed from the mounting portion 1a of the base 1 or one of its surroundings to the outside of the light emitting device, and 6 denotes a conductive member that connects one end of the line conductor 1b and the electrode of the light emitting element 3. Yes, it is used for light emitting devices as needed.

  The substrate 1 is made of an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, ceramics such as glass ceramics, or an insulator such as epoxy resin or liquid crystal polymer (LCP), and is mounted on the upper surface thereof. The light emitting element 3 is placed on the part 1 a and functions as a support member that supports the light emitting element 3.

  When the substrate 1 is made of ceramics or the like, a metal paste layer mainly composed of a metal such as tungsten (W) or molybdenum (Mo) -manganese (Mn) is formed on a plurality of green sheets to be the substrate 1, By firing the substrate 1 and the metal paste layer at the same time, the substrate 1 having the wiring conductor 1b is formed. That is, when the substrate 1 is made of ceramics, in order to electrically connect the inside and outside of the light emitting device, a wiring conductor made of a metallized layer and a metal plating layer mainly composed of W, Mo, Mn, copper (Cu) or the like. 1b is formed.

  When the substrate 1 is an insulator made of resin, the wiring conductor 1b is embedded in the substrate 1 with lead terminals made of Cu, iron (Fe) -nickel (Ni) -cobalt (Co) alloy, Fe-Ni alloy, or the like. Then, one end of the lead terminal is led out to the mounting portion, and the other end is led out to the side surface or the lower surface of the base 1 and exposed.

  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 via the conductive member 6, and the other end of the wiring conductor 1b led out to the side surface or the lower surface of the base 1 and the light emitting device drive. By electrically connecting the circuit board, the light emitting device driving circuit board and the light emitting element 3 can be electrically connected.

  In addition, the wiring conductor 1b has a metal layer excellent in corrosion resistance, such as a nickel (Ni) layer having a thickness of 0.5 to 9 μm and a gold (Au) layer having a thickness of 0.5 to 5 μm, attached to the exposed surface of the substrate 1. As a result, it is possible to effectively prevent the wiring conductor 1b from being oxidatively corroded, and to firmly join the light emitting element 3 with the conductive member 6 such as solder.

  Further, the wiring conductor 1b is not necessarily limited to the one embedded or formed in the base body 1. For example, the light emitting element 3 is led out from the upper surface of the light emitting device 3 to the outside of the upper surface of the light emitting device by a bonding wire or the like. You may connect to a light-emitting device drive circuit board.

  In addition, the base 1 is electrically connected to the wiring conductor 1b on its upper surface in order to suppress light transmission from the light emitting element 3 to the lower surface of the base 1 and to reflect light efficiently above the base 1. It is preferable that a metal layer such as aluminum (Al), silver (Ag), Au, platinum (Pt), or Cu is formed by a vapor deposition method, a plating method, or the like.

  Further, as shown in FIGS. 2, 4, 6, 8, and 9, the substrate 1 has a light reflecting surface 2 a that reflects light from the light emitting element 3 and fluorescence from the phosphor 5 on the inner peripheral surface. A frame body 2 having a surface surrounding the mounting portion 1a on the upper surface of the base body 1 so that Ag-Cu, lead (Pb) -tin (Sn), Au-Sn, Au-silicon (Si), Sn-Ag- It may be attached with a metal brazing material such as Cu, a bonding material such as solder, or a resin bonding material (not shown) such as silicone, epoxy, or acrylic. The frame body 2 functions as a support member that supports the wavelength conversion member 4 while protecting the light emitting element 3 from the external environment.

  The bonding material for bonding the frame 2 and the base body 1 may be appropriately selected in consideration of the material of the base body 1 and the frame body 2, the thermal expansion coefficient, and the like, and is not particularly limited. Further, when high reliability is required for joining the base body 1 and the frame body 2, a metal brazing material or solder may be used.

  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.

  In the case where the base 1 and the frame 2 are made of an insulator made of a thermosetting resin such as an epoxy resin or LCP, or a resin such as a thermoplastic resin, the base 1 and the frame 2 are formed by a mold in which the base 1 and the frame 2 are integrally formed. It can also be formed by integrally molding an insulator made of resin and a metal lead.

  Further, the frame 2 has a light reflecting surface 2a whose inner peripheral surface efficiently reflects the light of the light emitting element 3, and the light emitting element 3 is emitted from the light emitting element 3 by the configuration surrounded by the light reflecting surface 2a. The light and the fluorescence emitted from the wavelength conversion member 4 are efficiently reflected above the light emitting device, and the absorption and transmission of light by the base 1 and the frame 2 are effectively suppressed. Radiant light intensity and brightness can be significantly improved.

  The light reflecting surface 2a includes a frame 2 made of metal such as Al, Ag, Au, Pt, titanium (Ti), chromium (Cr), Cu, white ceramics, white epoxy resin, LCP, or the like. It is formed by mirror finishing by cutting, mold forming, electric field polishing, scientific polishing or the like. Alternatively, a metal mirror surface such as Al, Ag, Au or the like is formed on the inner peripheral surface of the frame 2 by metal plating or vapor deposition, or aluminum oxide is applied to an uncured transparent resin such as an epoxy resin, a silicone resin, or an acrylic resin. Alternatively, the light reflecting surface 2a may be formed by applying and curing a paste-like reflective material containing ceramic particles such as titanium oxide and zirconium oxide. 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, epoxy resin and acrylic resin. As a result, the corrosion resistance, chemical resistance, and weather resistance of the light reflecting surface 2a are improved.

  Moreover, as shown in FIG. 2, the light reflecting surface 2a is preferably inclined so as to spread outward as it goes upward. As a result, the light reflecting surface 2a can efficiently reflect the light emitted from the light emitting element 3 and the fluorescence emitted from the phosphor 5 upward of the light emitting device.

  In addition, when the light reflection surface 2a has an arithmetic average roughness Ra of 4 μm or less, the light reflection surface 2a can reflect the light from the light emitting element 3 well above the light emitting device with low loss. Thereby, for example, in the light emitting device that emits visible light directly by mixing the light from the light emitting element 3 to the outside and mixing it with the fluorescent light emitted from the phosphor 5, the light emission efficiency is improved.

  Further, when the arithmetic average roughness Ra of the surface of the light reflecting surface 2a is larger than 4 μm, the light from the light emitting element 3 can be diffusely reflected above the light emitting device by the light reflecting surface 2a. In the light emitting device that almost converts the wavelength of the excitation light from the light emitting element 3 by the wavelength converting member 4, the entire phosphor 5 filled in the wavelength converting member 4 can be efficiently irradiated with the excitation light from the light emitting element 3. As a result, fluorescence corresponding to the quantum efficiency can be generated from the phosphor 5, and the light output of the light emitting device is improved and the light emission efficiency is improved.

  When the arithmetic mean roughness Ra is less than 0.004 μm, the light reflecting surface 2a is difficult to form such a surface stably and efficiently, and the product cost tends to increase. Therefore, the arithmetic average roughness of the light reflecting surface 2a is more preferably 0.004 μm or more. In addition, when the arithmetic average roughness Ra is 0.5 μm or more, it is difficult to irradiate the entire phosphor 5 by diffusing the excitation light from the light emitting element 3 on the light reflecting surface 2a on such a surface. From this, fluorescence corresponding to the quantum efficiency is not emitted, and the light output of the light emitting device decreases, and the light emission efficiency of the light emitting device decreases. Therefore, the arithmetic average roughness of the light reflecting surface 2a may be 0.004 to 500 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 FIGS. 2, 4, 6, 8, and 9, and may have an arc shape, for example, a parabolic surface. Or a curved surface such as a hyperboloid. In the case of the circular arc shape, the light of the light emitting element 3 can be condensed and the light having directivity or diffusibility can be uniformly emitted upward.

  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 or light of various colors from the light emitting device with good visibility, the light emitting element 3 has a peak wavelength of 200 to 500 nm. It is preferable that the device emits light from ultraviolet light to near ultraviolet light and 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, a silicon carbide (SiC) compound semiconductor, a zinc oxide compound semiconductor, a zinc selenide compound semiconductor, a diamond compound semiconductor, a boron nitride compound semiconductor, or the like is used.

  The light emitting element 3 has a metal bump using a solder material such as Au-Sn, Sn-Ag, Sn-Ag-Cu, or Sn-Pb, or a metal bump, or a metal using a metal such as Au or Ag. It is electrically connected to the wiring conductor 1b by flip chip mounting through a conductive member 6 made of a conductive resin made of a resin such as a bump and an epoxy resin containing a metal powder such as Ag. 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 150 ° C. to 350 ° C., whereby the electrode of the light emitting element 3 and the wiring conductor 1 b are electrically connected by the conductive member 6. A method of manufacturing a connected light emitting device, or a conductive member 6 made of a solder material such as paste Au—Sn or Pb—Sn is placed on the wiring conductor 1b using a dispenser or the like, and the whole is 150 ° C. to After heating at about 350 ° C., the light emitting element 3 is mounted so that the electrode of the light emitting element 3 and the upper surface of the conductive member 6 are in contact with each other, and the electrode of the light emitting element 3 and the wiring conductor 1 b are electrically connected by the conductive member 6. Connected light emitting devices And a method of making. Further, for example, a method of electrically connecting the wiring conductor 1b and the electrodes of the light emitting element 3 with a conductive member 6 such as a bonding wire may be used, and this method can only be used for flip chip mounting.

  The light emitting element 3 is placed on the mounting portion 1a and electrically connected to the wiring conductor 1b via the conductive member 6, and then the phosphor 5 is excited by the light of the light emitting element 3 and emits fluorescence. It coat | covers with the wavelength conversion member 4 which consists of a contained transparent member.

  The first wavelength conversion member 4a of the light emitting device of the present invention has a small difference in refractive index from the light emitting element 3, and has a high transmittance with respect to light from the ultraviolet light region to the visible light region. In addition, a transparent member made of transparent resin such as acrylic resin or fluorine resin, or transparent glass such as low melting point glass or sol-gel glass, contains the first phosphor 5a that emits fluorescence using light from the light emitting element 3 as excitation light. It consists of

  The second wavelength conversion member 4b of the light emitting device of the present invention has a small refractive index difference from the first wavelength conversion member 4a and has a high transmittance with respect to light from the ultraviolet light region to the visible light region. Second fluorescence that emits fluorescence using light from the light-emitting element 3 as excitation light on a transparent member made of transparent resin such as resin, urea resin, acrylic resin, and fluorine resin, or transparent glass such as low-melting glass or sol-gel glass It contains the body 5b.

  The transparent member may be appropriately selected in consideration of the material of the substrate 1 and the frame 2, the thermal expansion coefficient, the light refractive index, and the like, and is not particularly limited. In addition, it is effective to reduce the refractive index difference between the light emitting element 3 and the transparent member containing the first phosphor 5a, thereby causing a light reflection loss due to the refractive index difference between the light emitting element 3 and the transparent member. In addition, the light can be efficiently extracted from the inside of the light emitting element 3 to the outside. The wavelength conversion member 4 includes the first wavelength conversion unit 4a and the second wavelength conversion unit 4b in which the transparent member containing the first phosphor 5a and the second phosphor 5b is uncured. It is formed by a method such as injecting in order so as to cover the light emitting element 3 inside the frame 2 with an injector such as a dispenser, and thermosetting (see FIG. 2).

  Or the wavelength conversion member 4 arrange | positions the 1st wavelength conversion part 4a with which the transparent member containing the 1st fluorescent substance 5a is an unhardened state so that the light emitting element 3 may be coat | covered with injectors, such as a dispenser. Alternatively, the light-emitting element 3 is disposed so as to be covered and thermally cured, and then the second phosphor 5b is contained in an uncured transparent member to form a plate and cured. The film-like second wavelength conversion member 4b is formed by a method such as placing it on the first wavelength conversion portion 4a via a transparent member, and fixing the adhesion (see FIG. 6).

  Further, the wavelength conversion member 4 includes a first wavelength conversion unit 4a containing a first phosphor 5a having a low absorption rate of light emitted from the light emitting element 3, and a light absorption rate higher than that of the first phosphor 5a. The second wavelength conversion section 4b containing the second phosphor 5b having a high wavelength, and the first wavelength conversion section 4a is disposed on the side close to the light emitting element 3, and the second wavelength conversion section 4b It arrange | positions above the 1st wavelength conversion part 4a. That is, by arranging the first phosphor 5a having a low absorption rate of light emitted from the light emitting element 3 so as to be close to the light emitting element 3, the first phosphor 5a and the second phosphor 5b are Fluorescence corresponding to each quantum efficiency can be stably generated, the light output of the light emitting device can be stably improved, and the unevenness and variation of the color of the output light can be suppressed.

  When the first phosphor 5a and the second phosphor 5b are mixed and arranged, the amount of light absorbed from the light emitting element 3 of the second phosphor 5b becomes large, and the light emission of the first phosphor 5a. The amount of light absorbed from the element 3 is reduced. Accordingly, the fluorescence corresponding to the quantum efficiency generated from the first phosphor 5a is reduced, and the light output of the light emitting device is reduced, whereby the wavelength conversion efficiency of the wavelength conversion member 4 and the light emission efficiency of the light emitting device are reduced. . Further, in the light emitting device, the first and second phosphors 5a and 5b are partially absorbed by the first and second phosphors 5a and 5b depending on the dispersion state of the first and second phosphors 5a and 5b in the wavelength conversion member 4. Large variations occur. Accordingly, the light emitting device cannot stably emit a desired amount of fluorescence from the first and second phosphors 5a and 5b, thereby causing unevenness and variations in the color of light emitted from the light emitting device. Will end up.

  On the other hand, according to the configuration of the present invention, the first phosphors 5a having a low absorptance are individually arranged in the vicinity of the light emitting element 3, so that the excitation light emitted by the second phosphors 5b having different absorptances can be obtained. Since absorption can be suppressed, the 1st fluorescent substance 5a can generate the fluorescence according to the quantum efficiency. As a result, a desired output of fluorescence can be emitted from the first phosphor 5a, and a decrease in the light emission efficiency of the light emitting device can be suppressed. Furthermore, it is possible to suppress color unevenness and color variation of light emitted from the light emitting device, which is caused by the dispersion state of the first and second phosphors 5a and 5b in the wavelength conversion member 4.

  In addition, the second phosphor 5b is configured so that the entire second wavelength conversion unit 4b is received by the light directly from the light emitting element 3 or the light from the light emitting element 3 that is reflected and diffused by the first phosphor 5a. It is excited efficiently. That is, the light from the light emitting element 3 is diffused by the first phosphor 5a in the first wavelength conversion unit 4a, and the diffused light of the light emitting element 3 is in the central part of the second wavelength conversion member 4b. As a result, the amount of the second phosphor 5b to be excited increases and the amount of fluorescence emitted according to the quantum efficiency of the second phosphor 5b increases. As a result, the light-emitting device of the present invention has improved wavelength conversion efficiency of the wavelength conversion member 4, light output to the outside of the light-emitting device, or light-emitting efficiency, and color unevenness on the light-emitting surface and irradiation surface of the light-emitting device. Color variation can be suppressed.

  In addition, it is preferable that the volume density of the 1st fluorescent substance 5a in the 1st wavelength conversion part 4a is made larger than the volume density of the 2nd fluorescent substance 5b in the 2nd wavelength conversion part 4b. As a result, the light from the light emitting element 3 directly excites the first phosphor 5a, and a part of the light from the light emitting element 3 is reflected and diffused by the first phosphor 5a with low loss. The first phosphor 5a can be excited without any unevenness by propagating through the one wavelength converter 4a. Furthermore, a part of the light from the light emitting element 3 that has propagated to the upper surface of the first wavelength conversion unit 4a and entered the second wavelength conversion unit 4b is filled with the first phosphor 5a at a high density. The second phosphor 5b is diffused in various directions by the first wavelength conversion unit 4a and uniformly irradiated to the second phosphor 5b having a high absorption rate in the second wavelength conversion unit 4b. Is converted into a wavelength and emitted outside the light emitting device. Therefore, the probability that each of the first phosphor 5a and the second phosphor 5b is excited is improved, and the amount of fluorescence emitted from these phosphors 5 is increased.

  For example, when the light from the light emitting element 3 generates high energy light from ultraviolet light to near ultraviolet light, the light from the light emitting element 3 is efficiently absorbed by the first phosphor 5a and the second phosphor 5b. Thus, the wavelength conversion reduces the amount of high-energy light emitted to the outside of the light-emitting device, and reduces the light deterioration of components arranged outside the light-emitting device.

  Further, the second phosphor 5b has a good absorption rate of light from the light emitting element 3 that has passed through the first wavelength conversion unit 4a, and the second wavelength conversion unit 4b including the second phosphor 5b emits light. Therefore, the light from the light emitting element 3 emitted to the outside of the light emitting device (direct light not converted into fluorescence) can be sufficiently reduced. As a result, when the wavelength spectrum of the light emitting element 3 is in the ultraviolet region to the near ultraviolet region, even if a substance that easily causes light degradation is arranged around the light emitting device, adverse effects on the substance can be reduced.

  Further, instead of changing the volume density of the first phosphor 5a and the second phosphor 5b included in each of the first wavelength converter 4a and the second wavelength converter 4b, the first wavelength converter The volume density of the first phosphor 5a included in 4a and the volume density of the second phosphor 5b included in the second wavelength converter 4b are set to be approximately the same, and the thickness of the first wavelength converter 4a is set to the second You may make it thicker than the thickness of the wavelength conversion part 4b.

  Further, the volume density of the first and second phosphors 5a and 5b and the thickness of the first and second wavelength converters 4a and 4b may be changed in combination. For example, the thickness of the first wavelength conversion unit 4a is made slightly thicker than the thickness of the second wavelength conversion unit 4b. Instead, the volume density of the first phosphor 5a of the first wavelength conversion unit 4a is changed to the second. The first and second phosphors 5a and 5b contained in the first and second wavelength conversion members 4a and 4b are made slightly larger than the volume density of the second phosphor 5b of the wavelength conversion unit 4b. The amount of each may be adjusted to be constant.

  In addition, when the 2nd wavelength conversion part 4b is arrange | positioned at the side close | similar to the light emitting element 3, and the 1st wavelength conversion part 4a is arrange | positioned above this 2nd wavelength conversion part 4b, a 2nd high absorption factor The light of the light emitting element 3 absorbed by the phosphor 5b increases, but the light that propagates above the second wavelength conversion unit 4b and enters the first wavelength conversion unit 4a decreases. The first phosphor 5a contained in the first wavelength conversion unit 4a arranged on the upper side of the wavelength conversion unit 4b cannot be excited efficiently. That is, since the wavelength conversion efficiency of the first wavelength conversion unit 4a including the first phosphor 5a is significantly reduced, the light emission efficiency of the light emitting device is deteriorated.

  Moreover, when the volume density of the 1st fluorescent substance 5a in the 1st wavelength conversion part 4a is smaller than the volume density of the 2nd fluorescent substance 5b in the 2nd wavelength conversion part 4b, the light of the light emitting element 3 is used. On the other hand, the first phosphor 5a included in the first wavelength converter 4a cannot efficiently reflect and diffuse, and the second wavelength converter 4b disposed above the first wavelength converter 4a. It is difficult to irradiate the light of the light emitting element 3 over the entire area, increase the amount of fluorescence emitted from the second phosphor 5b, increase the light output of the light emitting device, and improve the light emission efficiency. Become.

  Moreover, the transparent member containing the 1st, 2nd fluorescent substance 5a, 5b is the same material, or the refractive index of the transparent member of the 1st wavelength conversion part 4a is a transparent member of the 2nd wavelength conversion part 4b It is preferable that the refractive index is equal to or smaller than the refractive index of the transparent member of the second wavelength conversion unit 4b. When the transparent member is the same material, the light from the light emitting element 3 and the light from the first phosphor 5a are reduced in loss at the interface between the first wavelength conversion unit 4a and the second wavelength conversion unit 4b. The light output can be transmitted and the light output of the light emitting device does not decrease. Further, since the stress generated by the difference in thermal expansion coefficient between the first wavelength conversion unit 4a and the second wavelength conversion unit 4b is eliminated, the first wavelength conversion unit 4a and the second wavelength conversion unit 4b are separated. Can be suppressed, and the long-term reliability of the light-emitting device can be improved.

  Moreover, when the refractive index of the 1st wavelength conversion part 4a is smaller than the refractive index of the 2nd wavelength conversion part 4b, in the adhesion interface of the 1st wavelength conversion part 4a and the 2nd wavelength conversion part 4b, a light emitting element 3 and the light from the first phosphor 5a can enter the second wavelength conversion unit 4b without being totally reflected in accordance with Snell's law, and the second wavelength conversion unit 4b contains the second light contained in the second wavelength conversion unit 4b. Part of the fluorescence emitted from the phosphor 5b in the downward direction (on the first wavelength conversion unit 4a side) is totally reflected upward at the adhesive interface with the first wavelength conversion unit 4a according to Snell's law, and emits light. Easily released to the outside of the device. As a result, the fluorescence from the first phosphor 5a is efficiently emitted to the outside, and the fluorescence emitted from the second phosphor 5b is also efficiently emitted to the outside. Therefore, it is preferable that the refractive index of the first wavelength conversion unit 4a is smaller than the refractive index of the second wavelength conversion unit 4b in that the light output of the light emitting device can be improved.

  Preferably, the first wavelength conversion unit 4a and the second wavelength conversion unit 4b contain the first phosphor 5a and the second phosphor 5b in a translucent silicone resin. When the light emitted from the light-emitting element 3 is ultraviolet light or near-ultraviolet light, the silicone resin has high transmittance and small deterioration with respect to these light, and therefore, the light is emitted to the outside of the light emitting device for a long time with high output. Can be released.

  In addition, as shown in FIGS. 3, 4, 7, and 8, the wavelength conversion member 4 has a transmittance with respect to light from the ultraviolet light region to the visible light region that is filled so as to cover the light emitting element 3. A transparent resin such as a high-silicone resin, an epoxy resin, or a urea resin, or a phosphor 5 made of a transparent glass such as a low-melting-point glass or a sol-gel glass may be disposed on the upper side of the first translucent member 7. preferable. Thereby, since the first phosphor 5a is not disposed around the light-emitting element 3, the light emitted from the light-emitting element 3 is emitted by being confined around the light-emitting element 3 by the first phosphor 5a. Light absorption of the element 3 can be suppressed, and the light output of the light emitting device can be improved. That is, since the first phosphor 5 a is not disposed around the light emitting element 3, the light emitted from the light emitting element 3 is reflected by the first phosphor 5 a in the vicinity of the light emitting element 3 and returns to the light emitting element 3. Therefore, it is possible to suppress the absorption and the difficulty of being output to the outside.

  The first light-transmissive member 7 is made of the same material as the transparent member of the first wavelength conversion unit 4a, or is equal to the refractive index of the transparent member of the first wavelength conversion unit 4a, or the first It is preferable that the refractive index of the transparent member of the wavelength converter 4a is smaller than that of the transparent member. When the first translucent member 7 is made of the same material as that of the first wavelength conversion unit 4a, the light from the light emitting element 3 is emitted at the interface between the first translucent member 7 and the first wavelength conversion unit 4a. The light can be transmitted with low loss, and the light output of the light emitting device does not decrease. Furthermore, since the stress generated by the difference in thermal expansion coefficient between the first translucent member 7 and the first wavelength conversion unit 4a is eliminated, the first translucent member 7 and the first wavelength conversion unit 4a Can be prevented, and the long-term reliability of the light-emitting device can be improved.

  Moreover, when the refractive index of the 1st translucent member 7 is smaller than the refractive index of the 1st wavelength conversion part 4a, in the adhesive interface of the 1st translucent member 7 and the 1st wavelength conversion part 4a, The light from the light emitting element 3 can enter the first wavelength conversion unit 4a without being totally reflected according to Snell's law, and the first wavelength contained in the first and second wavelength conversion units 4a and 4a. , A part of the fluorescence emitted downward (from the light emitting element 3 side) from the second phosphors 5a and 5b is snelled at the bonding interface between the first light-transmissive member 7 and the first wavelength conversion unit 4a. According to the above law, the light is totally reflected upward and is easily emitted to the outside of the light emitting device. As a result, the fluorescence from the first and second phosphors 5a and 5b is efficiently emitted to the outside of the light emitting device, and the light output of the light emitting device can be improved. Therefore, it is preferable that the refractive index of the first translucent member 7 is smaller than the refractive index of the first wavelength conversion unit 4a in that the light output of the light emitting device can be improved.

  Further, as shown in FIGS. 1, 2, 5, 6, and 9, the first phosphor 5 a is contained in the transparent member and the first wavelength that covers the light emitting element 3 so as to be in contact with the light emitting element 3. The conversion member 4a or the first translucent member 7 that directly covers the light emitting element 3 so as to be in contact with the light emitting element 3 as shown in FIG. 3, FIG. 4, FIG. In order to improve the amount of light extracted from the light-emitting element 3, it is necessary to reduce the difference in refractive index from the light-emitting element 3. Usually, the refractive index of the light emitting layer of the light emitting element 3 is 2 or more. When a sapphire substrate is used as the substrate of the light emitting element 3, the refractive index of sapphire is about 1.7. Therefore, in order to improve the refractive index of the transparent member containing the first phosphor 5a and the first translucent member 7, a silicone resin having a high transmittance with respect to light in the ultraviolet region to the visible region, Oxides such as zinc oxide, titanium oxide, aluminum oxide, yttrium oxide, barium titanate, strontium titanate, zirconium oxide on transparent resins such as epoxy resin and urea resin, and transparent glass such as low melting point glass and sol-gel glass It is preferable to improve the refractive index by containing.

  In addition, the wavelength conversion member 4 shown in FIG. 3 and FIG. 4 was heat-cured by disposing the uncured first light-transmissive member 7 so as to cover the light-emitting element 3 with an injector such as a dispenser. Thereafter, the first wavelength conversion unit 4a in which the transparent member containing the first phosphor 5a is uncured is disposed so as to cover the first light-transmissive member 7 with an injector such as a dispenser. The second wavelength conversion unit 4b that is cured by heat is then formed by covering the first wavelength conversion unit 4a with an injector such as a dispenser.

  Alternatively, as shown in FIGS. 7 and 8, the uncured first light-transmissive member 7 is disposed so as to cover the light-emitting element 3 with an injector such as a dispenser and then thermally cured. A film-shaped first wavelength conversion member 4a produced by containing a first phosphor 5a in a cured transparent member and forming it into a plate shape and curing it is formed through the transparent member. After the optical member 7 is placed and bonded and fixed, the second phosphor 5b is contained in an uncured transparent member to form a plate, and this is cured to form a film. The second wavelength conversion member 4b is formed by a method such as placing the second wavelength conversion member 4b on the upper side of the first wavelength conversion unit 4a via the transparent member 8 and fixing the same.

Further, as shown in FIGS. 5 to 8, the second light transmitting member 8 may be provided between the first wavelength converting portion 4a and the second wavelength converting portion 4 b. Thereby, for example, when the first phosphor 5a undergoes a chemical reaction due to moisture in the operating environment and the quantum efficiency of the first phosphor 5a is reduced, the first wavelength conversion is performed by the second translucent member 8. Intrusion of moisture into the portion 4a can be suppressed. Therefore, deterioration of the quantum efficiency of the first phosphor 5a is suppressed, and the light emitting device can be operated at a high output for a long period. The second translucent member 8 has a transmittance ranging from near ultraviolet light to visible light such as transparent resin such as silicone resin, epoxy resin and urea resin, and transparent glass such as low melting point glass and sol-gel glass. By using a transparent material that is high and excellent in water resistance, deterioration of the quantum efficiency of the first phosphor 5a can be suppressed. In particular, when the first phosphor 5a is made of a sulfide-based phosphor, deterioration of quantum efficiency can be particularly effectively suppressed. Examples of sulfide-based phosphors include phosphors made of SrCaS: Eu, ZnS: Cu, Al, SrGa2S4: Eu, and the like.

  The second translucent member 8 is made of the same material as the transparent members of the first and second wavelength conversion units 4a and 4b, or the transparent members of the first and second wavelength conversion units 4a and 4b. It is preferable that the refractive index is equal to or higher than the refractive index of the transparent member of the first wavelength conversion unit 4a and smaller than the refractive index of the transparent member of the second wavelength conversion unit 4b. When the 2nd translucent member 8 is the same material as the 1st, 2nd wavelength conversion parts 4a and 4b, the 2nd translucent member 8 and the 1st, 2nd wavelength conversion parts 4a and 4b The light from the light emitting element 3 and the first phosphor 5a can be transmitted with low loss at the interface between the light emitting device and the light output of the light emitting device does not decrease. Further, since the stress generated by the difference in thermal expansion coefficient between the second translucent member 8 and the first and second wavelength conversion units 4a and 4b is eliminated, the second translucent member 8 and the first and second translucent members 8 Separation from the second wavelength conversion units 4a and 4b can be suppressed, and the long-term reliability of the light emitting device can be improved.

  Further, when the refractive index of the second light-transmissive member 8 is higher than the refractive index of the transparent member of the first wavelength conversion unit 4a and smaller than the refractive index of the transparent member of the second wavelength conversion unit 4b, the first The light emitting element 3 and the first wavelength conversion at the adhesive interface between the second wavelength conversion part 4a and the second light transmissive member 8 and at the adhesion interface between the second light transmissive member 8 and the second wavelength conversion part 4b. The light from the part 4a can enter the second light-transmissive member 8 and the second wavelength conversion part 4b without being totally reflected according to Snell's law, and further contained in the second wavelength conversion part 4b A part of the fluorescence emitted downward from the second phosphor 5b (on the first wavelength conversion unit 4a side) is the second wavelength conversion unit 4b, the second translucent member 8, and the first In accordance with Snell's law, it is totally reflected upward at the adhesive interface with the wavelength converting portion 4a and emitted to the outside of the light emitting device. It becomes easier. As a result, the fluorescence from the first and second phosphors 5a and 5b is efficiently emitted to the outside of the light emitting device, and the light output of the light emitting device can be improved. Therefore, the refractive index of the second translucent member 8 is higher than the refractive index of the transparent member of the first wavelength conversion unit 4a in that the light output of the light emitting device can be improved, and the second wavelength conversion. It is preferable that the refractive index is smaller than the refractive index of the transparent member of the portion 4b.

  5 and 6, the wavelength conversion member 4 includes the first wavelength conversion unit 4a in which the transparent member containing the first phosphor 5a is uncured, and the light emitting element 3 using an injector such as a dispenser. The second light-transmissive member 8 in an uncured state is disposed so as to cover the first wavelength conversion member 4a with an injector such as a dispenser. Curing is further performed, and the uncured second wavelength conversion unit 4b is disposed in order so as to cover the second translucent member 8 with an injector such as a dispenser and thermally cured, or an uncured transparent member. The second wavelength conversion member 4b in the form of a plate is formed by containing the second phosphor 5b and cured, and the second wavelength conversion member 4b is bonded and fixed via the second translucent member 8. It is formed by the method of letting it go.

  The wavelength conversion member 4 shown in FIG. 7 and FIG. 8 is configured by disposing the uncured first translucent member 7 so as to cover the light emitting element 3 with an injector such as a dispenser, or the light emitting element. The first wavelength conversion unit 4a in which the transparent member containing the first phosphor 5a is uncured is placed on the first wavelength conversion unit 4a with a syringe such as a dispenser. After being arranged so as to cover the translucent member 7 and thermally cured, the first phosphor 5a was contained in an uncured transparent member to form a plate, and this was prepared by curing. The film-shaped first wavelength conversion member 4a is placed on the first translucent member 7 through the transparent member and bonded and fixed, and then the uncured second translucent member 8 is placed. Is arranged so as to cover the first wavelength conversion member 4a with an injector such as a dispenser. Or after arrange | positioning so that the 1st wavelength conversion member 4a may be coat | covered and thermosetting, the 2nd translucent member 8 is coat | covered with injection | pourings, such as a dispenser, the 2nd wavelength conversion part 4b which is not hardened | cured. The film-like second wavelength conversion produced by arranging in order so as to be thermally cured, or forming a plate shape by containing the second phosphor 5b in an uncured transparent member, and curing the plate. The member 4b is formed by a method such as placing the member 4b on the second translucent member 8 via a transparent member and fixing the member 4b.

  Further, as shown in FIG. 9, glass, sapphire, quartz, or a resin (plastic) such as epoxy resin, silicone resin, acrylic resin, or the like so as to cover the second wavelength conversion portion 4 b on the upper surface of the frame 2. A lid 9 made of a transparent material may be placed and fixed. In this case, while protecting the light emitting element 3, the wiring conductor 1b, the electroconductive member 6, and the wavelength conversion member 4 installed inside the frame 3, the inside of the light emitting device 1 is hermetically sealed, and the light emitting element 3 is attached. A stable operation can be performed for a long time. Further, by forming the lid 9 in a lens shape and adding the function of an optical lens, it is possible to collect or disperse the light and extract the light outside the light emitting device with a desired radiation angle and intensity distribution.

The absorption rate and quantum efficiency of the phosphor can be generally measured by a measuring device such as a spectrofluorometer (for example, FP-6500 manufactured by JASCO Corporation). Such, the fluorescence spectrophotometer, the light from the light source is isolated to the excitation light L ₁ having a specific wavelength by the spectroscope, and contains a phosphor excitation light L ₁ to the isolated transparent member plate It is made to inject into the evaluation sample formed in the shape. Then, the fluorescence L ₂ emitted from the phosphor generated by the excitation light L ₁ and the excitation light L ₃ output without exciting the phosphor are detected while changing the wavelength of the excitation light L ₁ .

The photon number n4 photon number n1 is absorbed by the phosphor 5 of the excitation light L ₁ from the photon number n1 which is obtained by dividing the light energy [W] of the excitation light L ₁ at energy of 1 photon, light energy [W] of the excitation light L ₃ can be calculated by subtracting the number of photons n3 obtained by dividing the energy of the one-photon absorption of the phosphor 5 by dividing the photon number n4 photon number n1 The rate can be determined. Further, by dividing by the number of photons n4 absorbed photons number n2 which is obtained by dividing the phosphor 5 is emitted fluorescence L ₂ light energy [W] by energy of the one-photon phosphor 5, a fluorescent The quantum efficiency of the body 5 can be obtained.

  Next, the illuminating device of the present invention can be obtained by installing one light emitting device of the present invention in a predetermined arrangement and using it as a light source, or by using a plurality of light emitting devices of the present invention in, for example, a lattice shape Or a staggered, radial, or circular or polygonal light emitting device group composed of a plurality of light emitting devices, used as a light source arranged in a predetermined arrangement such as a concentric group of light emitting device groups. It can be set as a lighting device. Thereby, the light extraction efficiency can be improved, and the illumination device of the present invention having high radiated light intensity, axial luminous intensity and luminance can be provided.

  The illuminating device of the present invention, when utilizing the light emission of the light emitting element 3 made of a semiconductor, can have lower power consumption and longer life than the illuminating device using a conventional discharge, and is small in size and generating little heat. It can be set as a lighting device. As a result of being able to operate efficiently with low power, the amount of heat generated by the light emitting element 3 is small, fluctuations in the center wavelength of the light generated from the light emitting element 3 can be suppressed, and stable radiated light over a long period of time. While being able to irradiate light with an intensity and a radiated light angle (light distribution), it is possible to provide an illuminating device with less color unevenness and uneven illuminance distribution on the irradiated surface.

  In addition to installing the light emitting device of the present invention as a light source in a predetermined arrangement, by installing a reflector, 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 irradiate the light of light distribution.

  For example, as shown in FIG. 10 and FIG. 11, 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, and a required shape is formed around the light emitting device 101. In the case of an illuminating device in which an optically designed reflecting member 103 is installed, an arrangement in which light emitting devices 101 in adjacent rows are arranged between a plurality of light emitting devices 101 arranged in a row, so-called staggered arrangement. It is preferable. That is, when the light emitting devices 101 are arranged in a grid, 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. Thus, discomfort is likely to occur, but by adopting a staggered arrangement, glare is suppressed and discomfort to the human eye can be reduced. Furthermore, compared to the case where the light emitting devices 101 are arranged in a grid in the vertical and horizontal directions, 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 light emission. Heat accumulation in the light emitting device driving circuit board 102 on which the device 101 is mounted 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 with stable optical characteristics over a long period of time without causing discomfort 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 central 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 circuit board or 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 embodiments and examples, and various modifications can be made without departing from the scope of the present invention. For example, in the above embodiment, the first and second wavelength conversion units 4a and 4b containing the first and second phosphors 5a and 5b, respectively, in order to obtain two types of fluorescence are taken as an example. As described above, in order to obtain more wavelength conversion units, for example, the third fluorescence, the third wavelength conversion unit containing the third phosphor as in the above operation is replaced with the second wavelength conversion unit 4b. You may provide so that it may cover.

  In addition, when the second wavelength conversion unit 4b is the uppermost wavelength conversion unit 4b, the upper surface is a convex surface or a concave surface, which is used in combination with a function of converging light emitted from the light emitting device, or a fine diffusion surface. An uneven surface may be provided and used together with the function of a diffusion plate that diffuses emitted light.

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 sectional drawing which shows the other 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 sectional drawing which shows the other 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 sectional drawing which shows the other 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 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. 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 of the illuminating device of this invention. FIG. 13 is a cross-sectional view of the illumination device of FIG. It is sectional drawing of the conventional light-emitting device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1: Base 1a: Mounting part 1b: Wiring conductor 2: Frame 2a: Light reflection surface 3: Light emitting element 4: Wavelength conversion member 4a: First wavelength conversion part 4b: Second wavelength conversion part 5: Phosphor 5a : 1st fluorescent substance 5b: 2nd fluorescent substance 6: Conductive member 7: 1st translucent member 8: 2nd translucent member

Claims (3)

A substrate;
A light emitting element mounted on the upper surface of the substrate and emitting a first light;
A first wavelength conversion unit that is provided so as to cover the light emitting element and contains a first phosphor that is excited by the first light and generates second light in a transparent member;
A second wavelength detector that is provided to cover the first wavelength conversion unit, is excited by the first light to generate third light, and has a higher absorptance of the first light than the first phosphor; A second wavelength conversion unit containing the phosphor of :
A translucent member provided between the first wavelength conversion unit and the second wavelength conversion unit so as to cover the first wavelength conversion unit and to be covered by the second wavelength conversion unit; A light-emitting device comprising:   The volume density of the first phosphor contained in the first wavelength converter is the same as the volume density of the second phosphor contained in the second wavelength converter, and the first phosphor The light-emitting device according to claim 1, wherein a thickness of the wavelength conversion section is thicker than a thickness of the second wavelength conversion section. The illuminating device which used the light-emitting device of Claim 1 as a light source.

Images