JP2017224707A - Wavelength conversion member, method for manufacturing the same, and light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wavelength conversion member having high light extraction efficiency and capable of being manufactured by a simple process, a method for manufacturing the same, and a light-emitting device.SOLUTION: A wavelength conversion member 1 for converting a wavelength of excitation light emitted from a light source comprises a container 2 including a frame-like sidewall 4, a resin layer 6 arranged in the container 2 and including a phosphor, and a cover member 5 arranged above the container 2 and sealing the inside of the container 2. The cover member 5 is in a close contact with the resin layer 6. The cover member 5 is sealed to the container 2 by the resin layer 6 provided between the sidewall 4 and the cover member 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wavelength conversion member that converts the wavelength of light emitted from a light source into another wavelength, a method for manufacturing the same, and a light emitting device.

  In recent years, light-emitting devices using excitation light sources such as LEDs and LDs have attracted attention as next-generation light sources that replace fluorescent lamps and incandescent lamps. As an example of such a next-generation light source, a light-emitting device that combines an LED that emits blue light and a wavelength conversion member that absorbs part of the light from the LED and converts it into yellow light is widely known. This light emitting device emits white light that is a combined light of blue light emitted from the LED and yellow light emitted from the wavelength conversion member.

  Patent Document 1 below discloses a wavelength conversion member in which a resin in which phosphors such as quantum dots are dispersed is arranged in a space surrounded by a container and a cover member as an example of a wavelength conversion member. .

JP2015-220330A

  FIG. 1 of Patent Document 1 discloses a wavelength conversion member in which a space is formed between a resin in which a phosphor is dispersed and a cover member. When such a space exists, there is a problem that fluorescence is refracted at the interface between the resin and the space, and the light extraction efficiency is lowered.

  FIG. 2 of Patent Document 1 shows a wavelength conversion member in which the resin in which the phosphor is dispersed and the cover member are in close contact with each other and the space is not formed. Regarding the bonding between the container and the cover member, paragraph [0049] of Patent Document 1 discloses a bonding method using welding using a laser, anodic bonding, an inorganic bonding material, or the like. When these containers are used to join the container and the cover member to bring the resin and the cover member into close contact as shown in FIG. 2, it is predicted that a very complicated process is required.

  An object of the present invention is to provide a wavelength conversion member that has high light extraction efficiency and can be manufactured by a simple process, a manufacturing method thereof, and a light emitting device.

  The wavelength conversion member of the present invention is a wavelength conversion member for converting the wavelength of excitation light emitted from a light source, and is disposed in a container having a frame-shaped side wall and includes a phosphor. A resin layer and a cover member that is disposed above the container and seals the inside of the container, the cover member is in close contact with the resin layer, and the resin layer provided between the side wall and the cover member The cover member is sealed to the container.

  In the present invention, the resin layer has a first resin layer containing a phosphor and a second resin layer provided on the first resin layer, and the cover member is in close contact with the second resin layer. And may be sealed with a second resin layer provided between the side wall and the cover member. In this case, the second resin layer may not contain a phosphor.

  The light emitting device of the present invention includes a light source that emits excitation light and the wavelength conversion member of the present invention.

  The production method of the present invention is a method capable of producing the wavelength conversion member of the present invention, wherein the resin layer before curing is placed in a container so that the upper surface of the resin layer is located above the upper portion of the side wall. Filling the cover member, contacting the cover member with the top surface of the resin layer and placing the cover member above the container; and curing and shrinking the resin layer to bring the cover member into close contact with the cured resin layer And a step of sealing with a resin layer provided between the side wall and the cover member.

  In the production method of the present invention, the step of filling the container with the resin layer before curing is performed by filling the container with the first resin layer before curing, curing the first resin layer, and then before curing. A step of filling the second resin layer on the first resin layer may be included.

  ADVANTAGE OF THE INVENTION According to this invention, it can be set as the wavelength conversion member which has a high light extraction efficiency and can be manufactured by a simple process.

It is a typical sectional view showing the wavelength conversion member of a 1st embodiment of the present invention. It is typical sectional drawing which shows the process of manufacturing the wavelength conversion member of the 1st Embodiment of this invention. It is typical sectional drawing which shows the process of manufacturing the wavelength conversion member of the 1st Embodiment of this invention. It is typical sectional drawing which shows the light-emitting device using the wavelength conversion member of the 1st Embodiment of this invention. It is typical sectional drawing which shows the wavelength conversion member of the 2nd Embodiment of this invention. It is typical sectional drawing which shows the wavelength conversion member of the 3rd Embodiment of this invention. It is a typical sectional view showing the wavelength conversion member of a comparative example.

  Hereinafter, preferred embodiments will be described. However, the following embodiments are merely examples, and the present invention is not limited to the following embodiments. Moreover, in each drawing, the member which has the substantially the same function may be referred with the same code | symbol.

(First embodiment)
FIG. 1 is a schematic cross-sectional view showing a wavelength conversion member according to the first embodiment of the present invention. The wavelength conversion member 1 of the present embodiment is disposed in a container 2 having a frame-like side wall 4, a resin layer 6 containing a phosphor, and the container 2. 2 and a cover member 5 for sealing the inside. The container 2 is comprised from the bottom part 3 and the side wall 4 which consist of a transparent base material. As shown in FIG. 1, in this embodiment, the cover member 5 is in close contact with the resin layer 6. The cover member 5 is sealed to the container 2 by a resin layer 6 provided between the side wall 4 and the cover member 5.

  The resin layer 6 contains a phosphor, and preferably contains phosphor particles dispersed therein. As the resin contained in the resin layer 6, for example, a curable resin such as an ultraviolet curable resin or a thermosetting resin is used. Specifically, for example, an epoxy curable resin, an acrylic ultraviolet curable resin, a silicone curable resin, or the like can be used. The curable resin is preferably a translucent resin.

  For example, quantum dots can be used as the phosphor. Examples of the quantum dot include II-VI group compounds and III-V group compounds. Examples of the II-VI group compound include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe and the like. Examples of the III-V group compound include InP, GaN, GaAs, GaP, AlN, AlP, AlSb, InN, InAs, and InSb. At least one selected from these compounds, or a composite of two or more of these can be used as quantum dots. Examples of the composite include those having a core-shell structure, such as those having a core-shell structure in which the surface of CdSe particles is coated with ZnS.

  The phosphor is not limited to quantum dots. For example, oxide phosphor, nitride phosphor, oxynitride phosphor, chloride phosphor, acid chloride phosphor, sulfide phosphor, oxysulfide Inorganic phosphor particles such as a product phosphor, a halide phosphor, a chalcogenide phosphor, an aluminate phosphor, a halophosphate phosphor, or a garnet compound phosphor may be used.

  The container 2 is comprised from the bottom part 3 and the side wall 4 as mentioned above. More specifically, the side wall 4 is provided on the bottom 3.

The bottom 3 can be made of a transparent material. As a material constituting the bottom portion 3, for example, glass can be used. Examples of the glass include SiO ₂ —B ₂ O ₃ —RO (R is Mg, Ca, Sr, or Ba) -based glass, SiO ₂ —B ₂ O ₃ —R ′ ₂ O (R ′ is Li, Na, or Ka). ) Glass, SiO ₂ —B ₂ O ₃ —RO—R ′ ₂ O glass, SnO—P ₂ O ₅ glass, TeO ₂ glass, Bi ₂ O ₃ glass, or the like can be used.

  The side wall 4 is preferably made of ceramics having a high reflectance. In this case, since excitation light and fluorescence can be reflected, the light utilization efficiency can be further enhanced. As a ceramic with high reflectance, for example, low temperature co-sintered ceramic (LTCC) can be mentioned. As the LTCC, for example, alumina-glass ceramics can be used.

  The bottom 3 and the side wall 4 can be joined by an inorganic joining material such as glass frit, welding, metal solder or the like. Moreover, the bottom part 3 and the side wall 4 may be integrally formed. In this case, the side wall 4 may be formed of glass.

The cover member 5 can be made of a transparent material. As a material constituting the cover member 5, for example, glass can be used. Examples of the glass include SiO ₂ —B ₂ O ₃ —RO (R is Mg, Ca, Sr, or Ba) -based glass, SiO ₂ —B ₂ O ₃ —R ′ ₂ O (R ′ is Li, Na, or Ka). ) Glass, SiO ₂ —B ₂ O ₃ —RO—R ′ ₂ O glass, SnO—P ₂ O ₅ glass, TeO ₂ glass, Bi ₂ O ₃ glass, or the like can be used.

  When the bottom 3 and the cover member 5 are made of glass, it is possible to further suppress the transmission of moisture and oxygen. In this case, since the phosphor contained in the resin layer 6 is difficult to deteriorate, a highly reliable wavelength conversion member can be obtained.

  FIG.2 and FIG.3 is typical sectional drawing which shows the process of manufacturing the wavelength conversion member of the 1st Embodiment of this invention. As shown in FIG. 2, the resin layer 7 before curing is filled in the container 2. The resin layer 7 before curing is made of a resin before the resin layer 6 is cured. Accordingly, the resin layer 7 contains a phosphor. When filling the container 2 with the resin layer 7, the resin layer 7 is filled so that the upper surface 7 a of the resin layer 7 is positioned above the upper portion 4 a of the side wall 4. Thus, when the resin layer 7 is cured to form the resin layer 6, the volume of the resin layer 6 is prevented from becoming smaller than the volume of the container 2. Since the volume of the resin layer 6 does not become smaller than the volume of the container 2, the cover member 5 can be kept flat without curving to the container 2 side. When applied to the light guide plate, it is possible to eliminate a gap between the cover member 5 and the light guide plate, and to suppress light loss.

  Next, as shown in FIG. 3, the cover member 5 is placed in contact with the upper surface 7 a of the resin layer 7 and above the container 2. In this state, the upper surface 7 a of the resin layer 7 is located above the upper portion 4 a of the side wall 4. Accordingly, the bottom surface of the cover member 5 is also located above the upper portion 4 a of the side wall 4.

  Next, the resin layer 7 is cured. When the resin of the resin layer 7 is a thermosetting resin, the resin layer 7 is cured by heating. At this time, the resin layer 7 is softened by heating and enters between the cover member 5 and the upper portion 4 a of the side wall 4. The resin layer 7 is cured while entering between the cover member 5 and the upper portion 4 a of the side wall 4, whereby the cover member 5 and the side wall 4 are sealed by the cured resin layer 6.

  When the resin of the resin layer 7 is an ultraviolet curable resin, it is preferable to press the cover member 5 downward to force the resin layer 7 to enter between the cover member 5 and the upper portion 4 a of the side wall 4. . In this state, the cover member 5 and the side wall 4 can be sealed by the cured resin layer 6 by irradiating the resin layer 7 with ultraviolet rays. Even when the resin of the resin layer 7 is a thermosetting resin, the cover member 5 may be pressed downward to force the resin layer 7 to enter between the cover member 5 and the upper portion 4a of the side wall 4. Good.

  As described above, the wavelength conversion member 1 of the present embodiment can be manufactured.

  FIG. 4 is a schematic cross-sectional view showing a light emitting device using the wavelength conversion member of the first embodiment. As shown in FIG. 4, the light emitting device 10 includes a light source 11 on the bottom 3 side of the wavelength conversion member 1 of the first embodiment. As the light source 11, an LED light source, a laser light source, or the like can be used.

  Excitation light emitted from the light source 11 passes through the bottom 3 of the container 2 and enters the resin layer 6. The phosphor contained in the resin layer 6 is excited by excitation light, and fluorescence is emitted from the phosphor. The fluorescence from the resin layer 6 is emitted to the outside through the cover member 5. For example, when blue light is used as the excitation light, the wavelength conversion member 1 converts the blue light into yellow light, combines the yellow light as fluorescence and the blue light that is excitation light, and emits white light. be able to.

  FIG. 7 is a schematic cross-sectional view showing a wavelength conversion member of a comparative example. In the wavelength conversion member 31 of the comparative example, a resin layer 36 containing a phosphor is disposed in a container 32 composed of a bottom 33 and a side wall 34, and the cover member 35 is sealed with a sealing material 38 made of glass frit or the like. It is constituted by. As shown in FIG. 7, in the wavelength conversion member 31 of the comparative example, a gap 39 is formed between the resin layer 36 and the cover member 35. The void 39 is formed by the shrinkage of the resin when the uncured resin filled in the container 32 is cured. When such a gap 39 is present, the difference in refractive index between the resin layer 36 and the gap 39 increases, so that a part of the light is reflected at this interface, and the light extraction efficiency decreases.

  In contrast, in the wavelength conversion member 1 of the present embodiment shown in FIG. 1, the cover member 5 is in close contact with the resin layer 6 and no gap is formed. For this reason, the light extraction efficiency can be improved. Further, in the wavelength conversion member 1 of the present embodiment, the cover member 5 is sealed to the container 2 by a resin layer 6 provided between the side wall 4 and the cover member 5. As described above, sealing of the cover member 5 can be performed in the step of forming the resin layer 6 by curing the resin layer 7. Therefore, according to this embodiment, a wavelength conversion member with high light extraction efficiency can be manufactured in a simple process.

(Second Embodiment)
FIG. 5 is a schematic cross-sectional view showing a wavelength conversion member according to the second embodiment of the present invention. As shown in FIG. 5, in this embodiment, the resin layer 6 shown in FIG. 1 is composed of a first resin layer 6a and a second resin layer 6b provided on the first resin layer 6a. ing. The cover member 5 is in close contact with the second resin layer 6 b, and the cover member 5 is sealed to the container 2 by the second resin layer 6 b provided between the side wall 4 and the cover member 5. The first resin layer 6a contains a phosphor. The second resin layer 6b may or may not contain a phosphor. In the present embodiment, the second resin layer 6b contains no phosphor. Therefore, in this embodiment, the 2nd resin layer 6b is comprised only from resin. When the second resin layer 6b contains a phosphor, the phosphor contained in the second resin layer 6b may be different from the phosphor contained in the first resin layer 6a.

  When the second resin layer 6b is provided on the first resin layer 6a, the second resin layer 6b prevents the first resin layer 6a containing the phosphor from coming into contact with water or oxygen. Therefore, it is possible to suppress deterioration of the phosphor.

  In this embodiment, since the cover member 5 is sealed by the second resin layer 6b, a resin excellent in sealing properties can be selected as the resin of the second resin layer 6b. For this reason, according to this embodiment, sealing property can be improved.

  Further, the refractive index of the resin of the second resin layer 6 b is preferably close to the refractive index of the resin of the first resin layer 6 a and the cover member 5. Thereby, it can reduce that light is refracted or reflected in the interface of the 1st resin layer 6a and the 2nd resin layer 6b, and the interface of the cover member 5 and the 2nd resin layer 6b, The light extraction efficiency can be increased. The difference between the refractive index of the resin of the second resin layer 6b and the refractive index of the resin of the first resin layer 6a is preferably 0.10 or less, more preferably 0.08 or less, and still more preferably Is 0.05 or less, particularly preferably 0.03 or less, and most preferably 0.01 or less. Further, the difference between the refractive index of the cover member 5 and the refractive index of the resin of the second resin layer 6b is preferably 0.20 or less, more preferably 0.12 or less, and still more preferably 0.00. Or less, particularly preferably 0.04 or less, and most preferably 0.01 or less.

  In the method for manufacturing a wavelength conversion member according to the present embodiment, the first resin layer before curing is filled in the container 2, the first resin layer is cured, and then the second resin layer before curing is changed to the first resin layer. It is preferable to fill the first resin layer 6a and then cure the second resin layer to form the second resin layer 6b. However, the present invention is not limited to this. The second resin layer before curing is filled on the first resin layer before curing, and then the first resin layer and the second resin layer are simultaneously cured. The first resin layer 6a and the second resin layer 6b may be used.

  Also in this embodiment, a wavelength conversion member with high light extraction efficiency can be manufactured by a simple process.

(Third embodiment)
FIG. 6 is a schematic cross-sectional view showing a wavelength conversion member according to a third embodiment of the present invention. As shown in FIG. 6, in this embodiment, a light source 11 is provided inside the container 2. Therefore, the wavelength conversion member of the present embodiment is configured as the light emitting device 20. About another structure, it is the same as that of 1st Embodiment.

  Also in this embodiment, a wavelength conversion member with high light extraction efficiency can be manufactured by a simple process.

DESCRIPTION OF SYMBOLS 1 ... Wavelength conversion member 2 ... Container 3 ... Bottom part 4 ... Side wall 4a ... Upper part 5 ... Cover member 6 ... Resin layer 6a ... 1st resin layer 6b ... 2nd resin layer 7 ... Resin layer 7a before hardening ... Before hardening The upper surface 10 of the resin layer 10 ... the light emitting device 11 ... the light source 20 ... the light emitting device

Claims (6)

A wavelength conversion member for converting the wavelength of excitation light emitted from a light source,
A container having a frame-shaped side wall;
A resin layer disposed in the container and containing a phosphor;
A cover member disposed above the container and sealing the inside of the container;
The wavelength conversion member, wherein the cover member is in close contact with the resin layer, and the cover member is sealed to the container by the resin layer provided between the side wall and the cover member. The resin layer is
A first resin layer containing the phosphor;
A second resin layer provided on the first resin layer;
Have
The wavelength conversion according to claim 1, wherein the cover member is in close contact with the second resin layer and is sealed by the second resin layer provided between the side wall and the cover member. Element.   The wavelength conversion member according to claim 2, wherein the second resin layer does not contain the phosphor. A light source that emits the excitation light;
The wavelength conversion member according to any one of claims 1 to 3,
A light emitting device comprising: A method for producing the wavelength conversion member according to any one of claims 1 to 3,
Filling the container with the resin layer before curing so that the upper surface of the resin layer is located above the upper part of the side wall;
Placing the cover member in close contact with the upper surface of the resin layer and disposing the cover member above the container;
Sealing with the resin layer provided between the side wall and the cover member in a state where the cover member is in close contact with the cured resin layer by curing and shrinking the resin layer; A method for manufacturing a wavelength conversion member. The step of filling the container with the resin layer before curing,
The first resin layer before curing is filled in the container, the first resin layer is cured, and then the second resin layer before curing is filled on the first resin layer. The manufacturing method of the wavelength conversion member of Claim 5 including a process.

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