JP4976895B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device using an LED chip (light emitting diode chip).

  Conventionally, light emission in which a desired mixed color light (for example, white light) is obtained by combining an LED chip and a phosphor that emits light of a light emission color different from that of the LED chip when excited by light emitted from the LED chip. Research and development of the apparatus is performed in various places (for example, refer to Patent Documents 1 and 2).

  Here, in Patent Document 1, as shown in FIG. 4, an LED chip 10 ′ that emits blue light, a mounting substrate 20 ′ on which the LED chip 10 ′ is mounted, and a mounting substrate in the LED chip 10 ′. A phosphor and a translucent material that are stacked on the surface side opposite to the 20 ′ side and are excited by light emitted from the LED chip 10 ′ to emit visible light (yellow light) having a longer wavelength than the LED chip 10 ′. The color conversion unit 60 ′ formed by the above, and the light emitted from the LED chip 10 ′ provided between the LED chip 10 ′ and the color conversion layer 60 ′ are transmitted and emitted from the phosphor of the color conversion unit 60 ′. Wavelength-selective filter layer 45 ′ that reflects visible light, and LED chip 10 ′, wavelength-selective filter layer 45 ′, and color conversion on the mounting surface side of LED chip 10 ′ on mounting substrate 20 ′ Light-emitting device and a 'lens 160 covering the' 60 are described.

Further, in Patent Document 2, as shown in FIG. 5, an LED chip 10 ′ that emits blue light and a cup portion 120 ′ that is formed of a part of a lead frame and the LED chip 10 ′ is mounted on the inner bottom surface. And a hemispherical sealing portion 50 ′ made of a sealing material that seals the LED chip 10 ′, and an LED excited by light emitted from the LED chip 10 ′ that is laminated on the surface side of the sealing portion 50 ′. A dome-shaped color conversion unit 60 ′ formed of a phosphor and a translucent material that emits visible light (yellow light) having a wavelength longer than that of the chip 10 ′, a sealing unit 50 ′, and a color conversion unit 60 ′ A wavelength selection filter layer 45 ′ that transmits light emitted from the LED chip 10 ′ and reflects visible light emitted from the phosphor of the color conversion unit 60 ′, and an LED chip in the cup unit 120 ′. The color conversion unit 60 ′ is mounted on the mounting surface side of 10 ′. Emitting device is described that includes a Cormorant lens 160 '. In the wavelength selection filter layer 45 ′, a TiO ₂ film having a relatively high refractive index and a SiO ₂ film having a relatively low refractive index are alternately laminated.
U.S. Pat. No. 5,817,752 (column 2, line 66-column 3, line 65, FIG. 1) US Pat. No. 6,155,699 (column 5, line 11 to line 40, column 5, line 62 to column 6, line 9, FIG. 2)

  By the way, in the light emitting device shown in FIG. 4 and FIG. 5, since the wavelength selection filter layer 45 ′ is provided between the LED chip 10 ′ and the color conversion unit 60 ′, the phosphor of the color conversion unit 60 ′ is used. It can be suppressed that part of the emitted visible light returns to the LED chip 10 ′ side and the light extraction efficiency is lowered.

  However, in the light emitting device having the configuration shown in FIG. 4, the blue light emitted from the side surface of the LED chip 10 ′ enters the lens 160 ′ without going through the color conversion unit 60 ′ and is emitted to the outside. Unevenness was likely to occur.

  On the other hand, in the light emitting device having the configuration shown in FIG. 5, since the color conversion unit 60 ′ is formed in a dome shape, the occurrence of uneven color is suppressed compared to the light emitting device having the configuration shown in FIG. 4. be able to.

  However, in the light emitting device having the configuration shown in FIGS. 4 and 5, the wavelength selection filter layer 45 ′ and the color conversion unit 60 ′ are stacked, and therefore, the heat generation is caused by the phosphor of the color conversion unit 60 ′. As a result, stress is applied to the wavelength selection filter layer 45 ′, and cracks may occur in the wavelength selection filter layer 45 ′, thereby reducing the light extraction efficiency.

  This invention is made | formed in view of the said reason, The objective is to provide the light-emitting device which can suppress generation | occurrence | production of the crack to a wavelength selection filter layer.

The invention of claim 1 is an LED chip that emits visible light, a mounting board on which the LED chip is mounted, and a dome-like shape that is disposed on the mounting surface side of the LED chip on the mounting board so as to surround the LED chip. A dome shape formed of an optical member, a fluorescent material that is excited by visible light emitted from the LED chip and emits visible light having a wavelength longer than that of the LED chip, and a translucent material, and is disposed so as to surround the optical member And a wavelength selection filter layer that is formed on the light emitting surface of the optical member and that transmits visible light emitted from the LED chip and reflects visible light emitted from the phosphor. shorter than the air layer is formed, is excited by visible light emitted from the LED chip first phosphor is a long wavelength and the phosphor than LED chips between the color conversion unit and A wavelength selective filter layer is provided with a dome-shaped second color conversion unit that is formed of a second phosphor that emits visible light and a translucent material and is located outside the first color conversion unit that is a color conversion unit. It has an optical characteristic of reflecting visible light radiated from the second phosphor, and another air layer is formed between the second color conversion unit and the first color conversion unit .

  According to this invention, between the wavelength selection filter layer that is formed on the light emitting surface of the optical member and transmits visible light emitted from the LED chip and reflects visible light emitted from the phosphor, and the color conversion unit. Since the air layer is formed, the thermal stress applied to the wavelength selection filter layer due to the heat generated in the color conversion unit can be reduced, and the occurrence of cracks in the wavelength selection filter layer can be suppressed.

Further, according to this invention, the first phosphor and the dome formed by the transparent material which emits visible light of longer wavelength than the excitation has been L ED chip by the visible light emitted from the L ED chip a first color conversion section of Jo, a second phosphor that emits L ED chips is excited by visible light emitted from L ED visible light having a shorter wavelength than even longer wavelengths and the first phosphor than the chip And a dome-shaped second color conversion unit formed of a translucent material and positioned outside the first color conversion unit, so that two types of first phosphor and second phosphor are provided. restrain the visible light emitted from the second phosphor is secondarily absorbed by the first phosphor having a peak emission wavelength longer having an emission peak wavelength in the phosphor sac Chi shorter wavelength It becomes possible . Furthermore, according to the present invention, visible light radiated from the second phosphor of the second color conversion unit becomes difficult to enter the first color conversion unit, and the light extraction efficiency to the outside can be increased.

Although it is an invention different from the present invention, an LED chip that emits visible light, a mounting board on which the LED chip is mounted, and an LED chip surrounding the LED chip on the mounting board are arranged. A dome-shaped optical member provided, a phosphor that is excited by visible light emitted from the LED chip and emits visible light having a wavelength longer than that of the LED chip, and a translucent material, and surrounds the optical member. A dome-shaped color converter disposed, and a wavelength selection filter layer that is formed on the light emitting surface of the optical member and transmits visible light emitted from the LED chip and reflects visible light emitted from the phosphor. An air layer is formed between the wavelength selection filter layer and the color conversion unit, and is excited by visible light emitted from the LED chip and has a longer wavelength than the LED chip and is a phosphor. A dome-shaped second color conversion unit that is formed of a second phosphor that emits visible light having a shorter wavelength than the light body and a light-transmitting material and that is located outside the first color conversion unit, which is a color conversion unit. The wavelength selection filter layer has an optical characteristic of reflecting visible light emitted from the second phosphor, and the second color conversion unit and the first color conversion unit are integrated, and the second there is, wherein the refractive index of the translucent material of the color conversion unit is larger than the refractive index of the translucent material of the first color conversion section.

According to another aspect of the present invention, a wavelength selective filter layer that is formed on the light emitting surface of an optical member and transmits visible light emitted from an LED chip and reflects visible light emitted from a phosphor, and color conversion. An air layer is formed between the wavelength selection filter layer and the thermal stress applied to the wavelength selection filter layer due to the heat generated in the color conversion unit can be reduced, and the generation of cracks in the wavelength selection filter layer can be suppressed. Can do. In addition, a dome-shaped first color conversion unit formed of a first phosphor that is excited by visible light emitted from the LED chip and emits visible light having a wavelength longer than that of the LED chip, and a translucent material; A first color formed by a second phosphor and a translucent material that is excited by visible light emitted from the LED chip and emits visible light having a longer wavelength than the LED chip and a shorter wavelength than the first phosphor. By providing the dome-shaped second color conversion unit located outside the conversion unit, the emission peak wavelength on the short wavelength side of the two types of phosphors of the first phosphor and the second phosphor It is possible to suppress the secondary absorption of the visible light emitted from the second phosphor having the second absorption by the first phosphor having the emission peak wavelength on the long wavelength side. Furthermore, it is possible to suppress the visible light emitted from the second phosphor of the second color conversion unit from entering the first color conversion unit, and to increase the light extraction efficiency to the outside.

  In the invention of claim 1, there is an effect that the occurrence of cracks in the wavelength selective filter layer can be suppressed.

(Embodiment 1)
As shown in FIG. 1, the light emitting device 1 of the present embodiment includes an LED chip 10 that emits visible light, a mounting substrate 20 on which the LED chip 10 is mounted, and a mounting surface side of the LED chip 10 on the mounting substrate 20. The dome-shaped optical member 40 disposed so as to surround the LED chip 10, the sealing portion 50 made of a sealing material that seals the LED chip 10 inside the optical member 40, and the LED chip 10. A dome-shaped color conversion unit 61 that is formed of a fluorescent material that is excited by visible light and emits visible light having a wavelength longer than that of the LED chip 10 and a light-transmitting material and that surrounds the optical member 40; A wavelength selection filter layer 45 that is formed on the light emitting surface of the optical member 40 and transmits visible light emitted from the LED chip 10 and reflects visible light emitted from the phosphor of the color conversion unit 61. Air layer 70 is formed between the wavelength selection filter layer 45 and the color conversion unit 61.

  In the light emitting device 1 of this embodiment, a GaN-based blue LED chip that emits blue light is used as the LED chip 10, and the phosphor of the color conversion unit 61 is excited by the blue light emitted from the LED chip 10 and yellow. Blue light emitted from the LED chip 10 and transmitted through the sealing unit 50, the optical member 40, the wavelength selection filter layer 45, and the color conversion unit 61, using a particulate yellow phosphor that emits light, and the color conversion unit It is possible to obtain white light composed of mixed light with yellow light emitted from 61 yellow phosphors.

  The LED chip 10 has an anode electrode (not shown) formed on one surface side (the lower surface side in FIG. 1) in the thickness direction and a cathode electrode (shown on the upper surface side in FIG. 1) in the other thickness direction. The other surface side is the light extraction surface 11 side, but blue light is also emitted from the side surface. Here, the anode electrode and the cathode electrode are formed of a laminated film of a lower layer Ni film and an upper layer Au film.

  The mounting substrate 20 includes a rectangular plate-shaped submount member 30 on which the LED chip 10 is mounted on one surface side, and a rectangular plate shape on which the submount member 30 is fixed to the central portion on the one surface side. The heat transfer plate 21 and a rectangular printed flexible printed wiring board fixed to one surface side (the upper surface side in FIG. 1) of the heat transfer plate 21 via, for example, a polyolefin-based fixing sheet (not shown). The wiring board 22 has a rectangular window hole 24 that exposes the submount member 30 at the center. Therefore, the heat generated in the LED chip 10 is transferred to the submount member 30 and the heat transfer plate 21 without passing through the wiring board 22.

  The heat transfer plate 21 is based on a metal plate 21a made of Cu, and a coating film 21b made of an Au film is formed on both surfaces in the thickness direction of the metal plate 21a.

  On the other hand, the wiring substrate 22 is provided with a pair of wiring patterns 23 and 23 for feeding power to the LED chip 10 on one surface side of an insulating base material 22a made of a polyimide film. A resist layer 26 made of a white resin covering a portion where the wiring patterns 23, 23 are not formed in the conductive base material 22a is laminated. Here, in the LED chip 10, the cathode electrode is electrically connected to one wiring pattern 23 via the bonding wire 14, and the anode electrode is connected to the other via the electrode pattern 31 of the submount member 30 and the bonding wire 14. The wiring pattern 23 is electrically connected. Each of the wiring patterns 23 and 23 is formed in an outer peripheral shape slightly smaller than half of the outer peripheral shape of the insulating base material 22a. Further, FR4, FR5, paper phenol or the like may be employed as the material of the insulating base material 22a.

  The resist layer 26 is patterned so that two portions of each wiring pattern 23, 23 are exposed in the vicinity of the window hole 24 of the wiring substrate 22 and one portion of each wiring pattern 23, 23 is exposed in the peripheral portion of the wiring substrate 22. In each wiring pattern 23, 23, a portion exposed in the vicinity of the window hole 24 of the wiring substrate 22 constitutes a terminal portion 23 a to which the bonding wire 14 is connected, and a circle exposed at the peripheral portion of the wiring substrate 22. The part of the shape constitutes an electrode part 23b for external connection. In addition, the wiring patterns 23 and 23 of the wiring board 22 are comprised by the laminated film of Cu film | membrane, Ni film | membrane, and Au film | membrane, and the uppermost layer is Au film | membrane.

  The submount member 30 is made of AlN having a relatively high thermal conductivity and electrical insulation, and has a planar size larger than the chip size of the LED chip 10. A stress relieving function that relieves stress acting on the LED chip 10 due to a difference in linear expansion coefficient with the LED chip 10, and heat generated in the LED chip 10 in a range wider than the chip size of the LED chip 10 in the heat transfer plate 21 It has a heat conduction function to transfer heat to the. Therefore, in the light emitting device 1 of the present embodiment, the stress acting on the LED chip 10 due to the difference in linear expansion coefficient between the LED chip 10 and the heat transfer plate 21 can be relieved, and the heat generated in the LED chip 10 can be reduced. Can be efficiently radiated through the submount member 30 and the heat transfer plate 21.

  In the present embodiment, AlN having a relatively high thermal conductivity and insulating properties is adopted as the material of the submount member 30, but the material of the submount member 30 is not limited to AlN, for example, composite SiC, Si Etc. may be adopted. Further, the electrode pattern 31 is formed on one surface side of the submount member 30 to be joined to the anode electrode that is an electrode on the submount member 30 side of the LED chip 10, and the LED pattern 31 is surrounded by the LED pattern 31. A reflective film 32 that reflects light emitted from the side surface of the chip 10 is formed. Therefore, visible light radiated from the side surface of the LED chip 10 can be prevented from being absorbed by the submount member 30, and the light extraction efficiency to the outside can be further increased. Here, the electrode pattern 31 is formed of an alloy of Au and Sn containing Au as a main component (for example, 80Au-20Sn, 70Au-30Sn, etc.). The reflective film 32 is made of Al, but is not limited to Al, and may be made of Ag, Ni, Au, or the like.

  In the light emitting device 1 of the present embodiment, the thickness dimension of the submount member 30 is set so that the surface of the submount member 30 is farther from the heat transfer plate 21 than the surface of the resist layer 26 of the wiring board 22. In addition, light emitted from the LED chip 10 to the side can be prevented from being absorbed by the wiring board 22 through the inner peripheral surface of the window hole 24 of the wiring board 22.

  As a sealing material which is a material of the above-mentioned sealing part 50, although silicone resin is used, not only silicone resin but an epoxy resin etc. may be used, for example.

  The optical member 40 is a molded product of a translucent material (for example, silicone resin) and is formed in a dome shape. Here, in this embodiment, since the optical member 40 is formed of silicone resin, the difference in refractive index and the linear expansion coefficient between the optical member 40 and the sealing portion 50 can be reduced. In addition, when the sealing material which is the material of the sealing part 50 is an epoxy resin, it is preferable that the optical member 40 is also formed of an epoxy resin. In addition, the optical member 40 may be fixed to the mounting substrate 20 with an end edge (periphery of the opening) on the mounting substrate 20 side using, for example, an adhesive (for example, silicone resin, epoxy resin).

  By the way, in forming the sealing portion 50 described above, after the LED chip 10 is mounted on the mounting substrate 20 and the LED chip 10 and the bonding wires 14 and 14 are electrically connected, the LED chip 10 and the bonding wires 14 and 14 are connected. 14 is covered with an uncured first sealing material (sealing resin material) which becomes a part of the sealing portion 50, and is made of the same material as the first sealing material, The sealing member 50 is formed by positioning the optical member 40 with the uncured second sealing material (sealing resin material) inside to be mounted on the mounting substrate 20 and curing each sealing material. What should I do? By forming the sealing part 50 in this way, it is possible to suppress the generation of voids in the sealing part 50 during the manufacturing process.

In the wavelength selection filter layer 45, the first dielectric film made of a high refractive index material having a relatively high refractive index and the second dielectric film made of a low refractive index material having a relatively low refractive index are alternately arranged. It is comprised by the laminated | stacked optical multilayer film. Here, the wavelength selection filter layer 45 may employ, for example, Ta ₂ O ₅ , TiO ₂ or the like as a high refractive index material, and employ, for example, SiO ₂ , MgF ₂ or the like as a low refractive index material. Note that the high refractive index material and the low refractive index material are not limited to the above-described materials. Further, the number and thickness of the dielectric films of the wavelength selection filter layer 45 include the refractive index of the optical member 40 in contact with the wavelength selection filter layer 45, the refractive index of each dielectric film, and the emission peak wavelength of the LED chip 10. And a cut-off wavelength between the light emission peak wavelength of the phosphor of the color conversion unit 61 and the like.

  The color conversion unit 61 is formed in a dome shape using a mixed material in which a particulate yellow phosphor that is excited by blue light emitted from the LED chip 10 and emits yellow light is dispersed in a translucent material made of silicone resin. Is formed. Here, in the present embodiment, since a silicone resin is employed as the translucent material of the color conversion unit 61, the difference in refractive index between the color conversion unit 61 and the sealing unit 50 can be reduced. The translucent material used as the material of the color conversion unit 61 is not limited to a silicone resin. For example, an organic / inorganic hybrid in which acrylic resin, glass, an organic component and an inorganic component are mixed and combined at the nm level or the molecular level. Materials etc. may be adopted. Moreover, the color conversion part 61 is formed so that thickness may become uniform. Moreover, the color conversion part 61 should just adhere the edge (periphery of an opening part) by the side of the mounting board | substrate 20 with respect to the mounting board | substrate 20, for example using an adhesive agent (for example, silicone resin, an epoxy resin, etc.).

  In the light emitting device 1 of the present embodiment described above, the wavelength selection filter that is formed on the light emitting surface of the optical member 40 and transmits the blue light emitted from the LED chip 10 and reflects the yellow light emitted from the yellow phosphor. Since the air layer 70 is formed between the layer 45 and the color conversion unit 61, the thermal stress applied to the wavelength selection filter layer 45 due to the heat generated in the color conversion unit 61 can be reduced, and the wavelength selection filter The generation of cracks in the layer 45 can be suppressed, the amount of light returning to the mounting board 20 with respect to yellow light emitted from the yellow phosphor can be reduced, and the absorption loss in the mounting board 20 and the like can be reduced.

  In this embodiment, the case where the visible light emitted from the LED chip 10 is blue light and the visible light emitted from the phosphor in the color conversion unit 61 is yellow light is illustrated. However, the color of each visible light is There is no particular limitation.

(Embodiment 2)
Incidentally, in the light emitting device 1 of the embodiment 1, by using a red phosphor and a green phosphor as a phosphor for definitive color conversion unit 61, a high color rendering property in comparison with the case of using only the yellow phosphor as a phosphor Although white light can be obtained, a part of the green light emitted from the green phosphor is secondarily absorbed by the red phosphor and converted into red light, so that the blue light from the LED chip 10 is converted into the red phosphor. Therefore, it is desirable to suppress such secondary absorption because the red light emission efficiency is lower than that in the case of directly converting to red light.

  On the other hand, the basic configuration of the light emitting device 1 of the present embodiment is substantially the same as that of the first embodiment, and is excited by visible light radiated from the LED chip 10 as shown in FIG. A second phosphor that emits visible light having a longer wavelength and shorter wavelength than the first phosphor that is the phosphor of the color conversion unit 61 (hereinafter referred to as the first color conversion unit 61), and a translucent material The difference is that a dome-shaped second color conversion unit 62 is formed and is positioned outside the first color conversion unit 61. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 1, and description is abbreviate | omitted.

  As in the first embodiment, the wavelength selection filter layer 45 in the present embodiment is composed of a first dielectric film made of a high refractive index material having a relatively high refractive index and a low refractive index material having a relatively low refractive index. The second dielectric film is composed of an optical multilayer film that is alternately laminated. The visible light that is transmitted from the LED chip 10 and is radiated from the first phosphor and the second light is transmitted. It is designed to have an optical property of reflecting visible light emitted from the phosphors.

  In the light emitting device 1 of the present embodiment, a GaN blue LED chip that emits blue light is used as the LED chip 10, and the blue light emitted from the LED chip 10 is used as the first phosphor of the first color conversion unit 61. Is used as a second phosphor of the second color conversion unit 62 and is excited by the blue light emitted from the LED chip 10 to emit green light. Blue light that is emitted from the LED chip 10 and passes through the sealing portion 50, the optical member 40, the wavelength selection filter layer 45, the first color conversion portion 61, and the second color conversion portion 62 using a particulate green phosphor. And mixed light of red light emitted from the red phosphor of the first color converter 61 and transmitted through the second color converter 62 and green light emitted from the green phosphor of the second color converter 62. Get white light Can.

  The first color conversion unit 61 uses a mixed material in which a particulate red phosphor that is excited by blue light emitted from the LED chip 10 and emits red light is dispersed in a translucent material made of silicone resin. It is formed in a dome shape. Here, in this embodiment, since the silicone resin is adopted as the translucent material of the first color conversion unit 61, the refractive index difference between the first color conversion unit 61 and the sealing unit 50 can be reduced. it can.

  The second color conversion unit 62 is a mixed material in which a particulate green phosphor that is excited by blue light emitted from the LED chip 10 and emits green light is dispersed in a translucent material made of silicone resin. It is formed in a larger dome shape than the first color conversion unit 61.

  In addition, the translucent material used as the material of the first color conversion unit 61 and the second color conversion unit 62 is not limited to a silicone resin. For example, an acrylic resin, glass, an organic component, and an inorganic component are at the nm level or the molecular level. Organic / inorganic hybrid materials mixed and bound together in the above may be employed. Further, the first color conversion unit 61 and the second color conversion unit 62 are formed so as to have a uniform thickness. In addition, the first color conversion unit 61 and the second color conversion unit 62 have, for example, an adhesive (for example, a silicone resin, an epoxy resin, or the like) with respect to the mounting substrate 20 at the edge on the mounting substrate 20 side (periphery of the opening). ) May be used.

In the light emitting device 1 of the present embodiment described above, the red phosphor that emits red light having a wavelength longer than that of the LED chip 10 by being excited by the blue light emitted from the LED chip 10 and the first translucent material. The formed dome-shaped first color conversion unit 61 and green fluorescent light that is excited by blue light emitted from the LED chip 10 and emits green light having a longer wavelength than the LED chip 10 and a shorter wavelength than the red phosphor. And a dome-shaped second color conversion unit 62 that is formed of the body and the second translucent material and is located outside the first color conversion unit 61, thereby providing a red phosphor and a green phosphor 2. is possible to prevent the green light emitted from the green phosphor in the phosphor sac Chi short wavelength side of the type having an emission peak wavelength is secondarily absorbed by the red phosphor having a peak emission wavelength longer Possible In addition, the wavelength which is formed on the light emitting surface of the optical member 40 and transmits the blue light emitted from the LED chip 10 and reflects the red light emitted from the red phosphor and the green light emitted from the green phosphor. Since the air layer 70 is formed between the selection filter layer 45 and the first color conversion unit 61, the thermal stress applied to the wavelength selection filter layer 45 due to the heat generated in the first color conversion unit 61 is reduced. Thus, the occurrence of cracks in the wavelength selective filter layer 45 can be suppressed, and the amount of light returning to the mounting substrate 20 with respect to red light emitted from the red phosphor and green light emitted from the green phosphor is reduced. In addition, absorption loss in the mounting substrate 20 or the like can be reduced.

  By the way, in the light-emitting device 1 of this embodiment, the 2nd color conversion part 62 and the 1st color conversion part 61 are integrated, and the refractive index of the translucent material of the 2nd color conversion part 62 is 1st color. If the translucent material of the second color converter 62 and the translucent material of the first color converter 61 are selected so as to be larger than the refractive index of the translucent material of the converter 61, the second color converter The green light radiated from the green phosphor 62 can be prevented from entering the first color conversion unit 61, and the light extraction efficiency to the outside can be increased. In addition, the 1st color conversion part 61 and the 2nd color conversion part 62 may be integrated by integrally molding, and may be integrated using a transparent adhesive (for example, silicone resin etc.). In the latter case, a plurality of types of second color conversion units 62 having different concentrations of the second phosphor are prepared in advance at the time of manufacture, and the second color conversion unit 62 is bonded to the first color conversion unit 61. If the mixed color light emitted through the first color conversion unit 61 is detected before and the second color conversion unit 62 having an appropriate density is bonded to the first color conversion unit 61 according to the detection result, the light emission Color variations for each device 1 can be reduced.

(Embodiment 3)
The basic configuration of the light emitting device 1 of the present embodiment is substantially the same as that of the second embodiment, and an air layer 80 is formed between the second color conversion unit 62 and the first color conversion unit 61 as shown in FIG. The only difference is that In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 2, and description is abbreviate | omitted.

  Therefore, in the light emitting device 1 of the present embodiment, since the air layer 80 is formed between the second color conversion unit 62 and the first color conversion unit 61, the second fluorescence of the second color conversion unit 62 is formed. Visible light emitted from the body is less likely to enter the first color conversion unit 61, and the light extraction efficiency to the outside can be increased.

  In the second and third embodiments, the visible light emitted from the LED chip 10 is blue light, the visible light emitted from the first phosphor in the first color conversion unit 61 is red light, and the second color conversion unit. Although the case where the visible light emitted from the second phosphor in 62 is green light is illustrated, the color of each visible light is not particularly limited.

1 is a schematic cross-sectional view of a light emitting device according to Embodiment 1. FIG. 6 is a schematic cross-sectional view of a light emitting device according to Embodiment 2. FIG. 6 is a schematic cross-sectional view of a light emitting device according to Embodiment 3. FIG. It is a schematic sectional drawing of the light-emitting device of a prior art example. It is a schematic sectional drawing of the light-emitting device of another prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light-emitting device 10 LED chip 11 Light extraction surface 20 Mounting board 40 Optical member 45 Wavelength selection filter layer 50 Sealing part 61 Color conversion part (1st color conversion part)
62 Second color conversion unit 70 Air layer 80 Air layer

Claims (1)

From an LED chip that emits visible light, a mounting substrate on which the LED chip is mounted, a dome-shaped optical member disposed on the mounting surface side of the LED chip on the mounting substrate so as to surround the LED chip, and the LED chip A dome-shaped color converter formed by a phosphor and a translucent material that is excited by the emitted visible light and emits visible light having a wavelength longer than that of the LED chip, and disposed around the optical member; A wavelength-selective filter layer that is formed on the light-emitting surface of the member and transmits visible light emitted from the LED chip and reflects visible light emitted from the phosphor, and between the wavelength-selective filter layer and the color conversion unit an air layer is formed, is excited by visible light emitted from the LED chip to emit a first visible light having a shorter wavelength than the phosphor is a long wavelength and the phosphor than LED chips 2 and a dome-shaped second color conversion unit that is formed of a translucent material and a translucent material and is located outside the first color conversion unit that is a color conversion unit, and the wavelength selection filter layer is formed from the second phosphor. A light emitting device having an optical characteristic of reflecting emitted visible light, wherein another air layer is formed between the second color conversion unit and the first color conversion unit .

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