KR20140135638A - Luminescent device - Google Patents

Abstract

Provided is a light emitting device capable of obtaining high brightness and a high output by improving heat resistance. A plurality of light emitting elements (12) composed of LEDs is mounted on a substrate (11). A wavelength conversion member (16) is arranged on the light emitting element (12) with a space (15) with the light emitting element (12). The wavelength conversion member (16) includes a grain-shaped phosphor and a binder. The binder is obtained by thermally processing a binder material including at least one from a group of an oxide precursor which becomes oxide by hydrolysis or oxidation, silicic acid compounds, silica, and amorphous silica at 500 degrees centigrade or less or through the reaction of the binder material at room temperature.

Description

[0001] LUMINESCENT DEVICE [0002]

The present invention relates to a light emitting device using a phosphor material.

As a light emitting device using a phosphor, for example, a phosphor is disposed in an epoxy resin or a silicone resin so as to be in contact with an LED (Light Emitting Diode) or an LD (Laser Diode) (see, for example, Patent Document 1 3). However, in this light emitting device, there has been a problem that it is difficult to increase the output by deteriorating or deforming the epoxy resin or the silicone resin due to high output of the LED or LD or heat generation of the LED or LD.

As a solution, a light emitting device in which a glass fluorescent substance is sealed instead of an epoxy resin or a silicone resin has been developed (see, for example, Patent Document 4, Patent Document 6). According to this light emitting device, structural heat resistance can be improved by using an inorganic material as a dispersion medium. However, a general low-melting glass is difficult to soften to such an extent that the phosphor can be dispersed unless heated to substantially 500 DEG C or higher (see Patent Document 5 Examples). For example, it is possible to lower the melting point by adding a heavy metal such as lead, but the application to which the element is allowed is extremely small at present from the viewpoint of the influence on the environment and the human body. Therefore, there is a problem that depending on the phosphor, the performance may deteriorate due to the influence of heat.

In addition, when a resin is used as the dispersion medium, even if the resin is disposed so as to be in contact with the LED or the LD, the inorganic material is hard and has a good adhesion to other materials, The stress is liable to accumulate due to the difference in thermal expansion, and the adhesion is hardly obtained. Therefore, there is a problem that it is very difficult to disperse the phosphor in an inorganic material and apply it directly to an LED element, an LD element or a substrate and fix it. Further, in the case of using an inorganic material, it is not practical to manufacture an LED element or an LD element and an inorganic material (in particular, glass) in a manufacturing process since heat treatment at a high temperature is required in the manufacturing process.

There is disclosed a light emitting device in which a phosphor is dispersed in a resin, an LED or an LD emitting heat as well as light, and a phosphor that receives light from the LED or LD and performs wavelength conversion are disposed at a distance Patent Document 7). In this method, the distance between the LED element or the LD element and the phosphor is set large, so that the influence of the heat can be reduced, and the restriction on the thermal design is reduced.

Japanese Patent No. 3364229 Japanese Patent No. 3824917 Japanese Unexamined Patent Application Publication No. 2011-204718 Japanese Patent Application Laid-Open No. 2009-91546 Japanese Patent Application Laid-Open No. 2008-143978 Japanese Patent Application Laid-Open No. 2008-115223 Japanese Patent No. 4562828

However, if the distance between the LED element or the LD element and the phosphor is large, a sufficient space is required. As a result, there is a problem that the LED module or the LD module is enlarged and its use is limited. In order to miniaturize the LED module or the LD module, it is necessary to bring the phosphor close to the LED element or the LD element as much as possible. However, if the LED is positioned closer to the LED element or the LD element, energy density per unit volume and unit area becomes high. In other words, it has been difficult to reduce the influence of heat and to miniaturize the LED module or the LD module.

An object of the present invention is to provide a light emitting device capable of improving heat resistance and downsizing.

The light emitting device of the present invention comprises a light emitting element and a wavelength converting member disposed with a space therebetween, wherein the wavelength converting member includes a particulate phosphor material and a binder, An oxide precursor which becomes an oxide by hydrolysis or oxidation, a binder raw material containing at least one kind selected from the group consisting of a silicate compound, silica and amorphous silica is reacted at room temperature or heat-treated at a temperature of 500 DEG C or lower.

According to the light emitting device of the present invention, since a space is provided between the light emitting element and the wavelength converting member and the inorganic material is mainly used for the binder of the wavelength conversion member, the heat resistance against heat generated from the light emitting element is improved So that high output and high brightness can be achieved, and the size can be reduced. Further, since the binder of the wavelength conversion member is obtained by a reaction at room temperature or a heat treatment at a temperature of 500 DEG C or less, deterioration of the characteristics of the phosphor material which can be formed even at a low temperature and deteriorates at high temperature can be suppressed.

Further, the wavelength conversion member can be easily formed by applying the raw material mixture containing the phosphor material and the binder raw material to one surface of the forming base material, reacting the raw material of the binder at room temperature, or heat- As shown in Fig.

1 is a view showing a configuration of a light emitting device according to a first embodiment of the present invention.
Fig. 2 is a characteristic diagram showing changes in luminance over time in an exposure test under a high temperature and high humidity environment of 85 캜 and 85% RH. Fig.
Fig. 3 is a characteristic diagram showing the relationship between the exposure temperature in the exposure test under a dry high-temperature environment and the luminescence brightness after 24 hours.
Fig. 4 is a characteristic diagram showing a change with time in luminance in an exposure test under a dry high-temperature environment of 150 캜. Fig.
Fig. 5 is a characteristic diagram showing changes in luminance over time in an exposure test under a drying high-temperature environment of 200 캜. Fig.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Fig. 1 shows a configuration of a light emitting device 10 according to a first embodiment of the present invention. In this light emitting device 10, a plurality of light emitting elements (light emitting elements) 12 made of LEDs are mounted on a substrate (substrate) 11, for example. As the excitation light, for example, ultraviolet light, blue light or green light is emitted to the light emitting element 12, and it is preferable to emit blue light among them. White light can be easily obtained, and ultraviolet light has an influence such as deterioration of surrounding members and the like, while blue light has such a small influence. The light emitting element 12 is electrically connected to a wiring (not shown) formed on the substrate 11 by a wire 13, for example. A reflector frame 14 is formed around the light emitting element 12 so as to surround the entire body.

A wavelength conversion member (wavelength conversion member) 16 is disposed on the light emitting element 12 with a space 15 between the light emitting element 12 and the light emitting element 12, for example. The wavelength converting member 16 is formed on one surface of a forming substrate 17 and the wavelength converting member 16 is formed on one surface of the forming substrate 17, (12) side of the light emitting element (12). The distance between the light emitting element 12 and the wavelength converting member 16 is preferably, for example, 1 mm or more, more preferably 2 mm or more. This is because the influence of heat generated from the light emitting element 12 can be effectively reduced. Further, the distance between the light emitting element 12 and the wavelength conversion member 16 is preferably less than 50 mm, for example. The influence of heat generated from the light emitting element 12 becomes sufficiently small, but the apparatus becomes large in size.

The wavelength converting member 16 includes, for example, a phosphor material in the form of a particle and a binder for bonding the phosphor material, and may include a filler if necessary.

The phosphor material includes, for example, phosphor particles, and a coating layer may be formed on the surface of the phosphor particles. Is, in the fluorescent substance particles, for example _{BaMgAl 10 O 17: Eu, ZnS} : Ag, Cl, BaAl 2 S 4: Eu or CaMgSi ₂ O _6: blue-based fluorescent material, Zn ₂ SiO, such as Eu _4: Mn, (Y, _{Gd) BO 3: Tb, ZnS} : Cu, Al, (M1) 2 SiO 4: Eu, (M1) (M2) 2 S: Eu, (M3) 3 Al 5 O 12: Ce, SiAlON: Eu, CaSiAlON: _{Eu, (M1) Si 2 O} 2 N: Eu or _{(Ba, Sr, Mg) 2} SiO 4: yellow or green phosphor, such as _{Eu, Mn, (M1) 3} SiO 5: Eu, (M1) S: Eu or _{(M1) (M2) 2 S} : Eu, (Y, Gd) BO 3: Eu, Y 2 O 2 S: Eu, (M1) 2 Si 5 N 8: Eu, (M1) AlSiN 3: Eu or YPVO ₄ : Eu, and other yellow, orange or red phosphors. In the above formula, M 1 includes at least one of Ba, Ca, Sr and Mg, M 2 contains at least one of Ga and Al, M 3 is at least one selected from the group consisting of Y, Gd, Lu and Te At least one of them.

In particular, the phosphor _{particles, (M3) 3 Al 5 O} 12: Ce, SiAlON: Eu, CaSiAlON: Eu, (M1) Si 2 O 2 N: Eu, (M1) 2 Si 5 N 8: Eu, (M1) _{AlSiN 3: Eu, (M1)} 2 SiO 4: Eu, (M1) 3 SiO 5: Eu, (M1) S: Eu or _{(M1) (M2) 2 S} : preferably constituted by Eu. M1, M2 and M3 are as described above. The phosphor particles are selected depending on the type of the light emitting element 12 or the like. One or two or more kinds of phosphor particles are used for the phosphor material. When a plurality of phosphor materials are used, they may be mixed and used. Alternatively, the phosphor materials may be laminated into a plurality of layers, or the respective phosphors may be arranged in a row. The particle diameter of the phosphor particles preferably has an average particle diameter of about 5 to 20 mu m since scattering toward the front is increased. If the average particle diameter is smaller than 5 탆, scattering is likely to occur in all directions. If the average particle diameter exceeds 20 탆, it is difficult to form the wavelength conversion member 16 by coating as described later.

The coating layer of the phosphor particles may be formed of a composite oxide of yttrium and aluminum such as rare earth oxide, zirconium oxide, titanium oxide, zinc oxide, aluminum oxide, yttrium aluminum garnet and the like, magnesium oxide and aluminum such as MgAl ₂ O ₄ Magnesium and at least one metal oxide selected from the group consisting of complex oxides of magnesium as a main component. Water resistance and ultraviolet ray characteristics can be improved. Of these, rare earth oxides are preferable, and rare earth oxides containing at least one element selected from the group consisting of yttrium, gadolinium, cerium and lanthanum are more preferable, and Y ₂ O ₃ is particularly preferable. A higher effect can be obtained and the cost can be suppressed.

The binder may be prepared by reacting a binder raw material containing at least one kind selected from the group consisting of an oxide precursor which becomes an oxide by hydrolysis or oxidation, a silicate compound, silica and amorphous silica at room temperature, Lt; / RTI > Examples of the oxide precursor include perhydropolysilazane, ethyl silicate, methyl silicate, aluminum phosphate, aluminum acetylacetonate, yttrium acetylacetonate, It is preferable that the main component is yttrium acetylacetonate, aluminum alcoholate and yttrium citrate. This is because these oxide precursors can readily become oxides by hydrolysis or oxidation at room temperature or heat treatment, and can function as a binder. As the binder, the oxide precursor does not need to react completely to become an oxide, and may include an unreacted portion or an incompletely reacted portion.

Among them, as the binder, a binder raw material containing at least one kind selected from the group consisting of a silicon oxide precursor, a silicate compound, silica and amorphous silica which becomes silicon oxide by hydrolysis or oxidation is reacted at room temperature, It is preferable to be obtained by heat treatment at a temperature. This is because the light transmittance from the light emitting element 12 can be increased. As the silicon oxide precursor, for example, perhydro polysilazane, ethyl silicate, and methyl silicate are preferably used as the main components.

As the silicate compound, for example, sodium silicate is preferable. The silicic acid compound may be a dehydrated one or a hydrate thereof. As the silica or amorphous silica, ultrafine particle powders of nano size, for example, are preferably used, and ultrafine particle powders having an average particle diameter of from 5 nm to 100 nm, for example, as diameters of primary particles are preferably used. Nm or less is more preferably used. These silicic acid compounds, silica or amorphous silica can be solidified by dissolving or dispersing in a solvent, followed by heat treatment and drying, to function as a binder.

The heat treatment temperature of the binder raw material is preferably set to 500 DEG C or less in order to reduce the thermal influence on the forming base material 17 and the phosphor material. When it is necessary to further reduce the thermal influence, the temperature is preferably 300 DEG C or less And more preferably 200 占 폚 or lower. Further, it is more preferable to react the binder raw material at room temperature because there is no thermal influence. It is preferable to select the type of the binder raw material from the forming base material 17 to be used and the heat resistance characteristics of the phosphor material to control the reaction of the binder raw material at room temperature or the number of times of heat treatment. The atmosphere during the heat treatment is preferably a non-oxidizing atmosphere such as a nitrogen atmosphere when the phosphor material is easily oxidized and deteriorated by heat. As described above, in the present embodiment, the phosphor can be heat-treated at a low temperature even for a phosphor material whose properties are deteriorated at a high temperature, and after the heat treatment, the phosphor material is covered with the oxide, Can be suppressed from being deteriorated.

The filler is preferably made of an inorganic material having a light-transmitting property, and examples thereof include silicon oxide particles, aluminum oxide particles, and zirconium oxide particles. More preferably, silicon oxide particles are preferable, and the shape thereof may be a crystal or a glass. It is more preferable that the filler is made of a material which is homogeneous with the binder. This is because the refractive index of the binder becomes the same and scattering can be reduced. The average particle diameter of the filler is preferably from about 10 탆 to about 20 탆, which is about the same as the average particle diameter of the phosphor particles. Since scattering in the forward direction is large, it is easy to control the distance between the phosphor particles.

The thickness of the wavelength conversion member 16 is preferably 30 μm or more and 1 mm or less, more preferably 50 μm or more and 500 μm or less, and more preferably 50 μm or more and 200 μm or less. When the thickness is thinner than 30 占 퐉, the amount of the fluorescent material decreases and the luminescence brightness decreases. If the thickness is larger than 1 mm, scattering and absorption of light increases, and it becomes difficult to extract light from the outside.

The forming base material 17 is made of, for example, glass or the like having light transmittance. As a characteristic of the glass, for example, it is preferable that the light transmittance is 90% or more in a wavelength range of 400 nm to 800 nm. The forming base material 17 may be in any form, and may be in the form of a circular plate or a rectangular plate. 1, a planar shape is shown, but it may be a concave shape, a convex shape, or a spherical shape.

The wavelength converting member 16 is formed by coating a raw material mixture containing a phosphor material and a binder raw material on one surface of a forming base material 17 and reacting the raw material of the binder at a room temperature or by performing heat treatment at a temperature of 500 DEG C or less . Concretely, first, for example, one or more kinds of phosphor materials, a binder raw material, a diluting solvent if necessary, and a filler if necessary are mixed to form a paste-like raw material mixture, For example, a printing method such as screen printing, a dispenser method, or a spray method. In particular, the printing method is preferable because the range of the viscosity of the slurry that can be handled is wide. The application may be repeatedly carried out until the required film thickness is obtained. Then, for example, the coated raw material mixture is dried to remove the diluting solvent. At that time, it may be heated to 500 deg. C or less, more preferably 300 deg. C or less, more preferably 200 deg. C or less as necessary. Accordingly, the raw material of the binder reacts at room temperature or heat treatment, or solidifies by heat treatment.

As described above, according to the present embodiment, since the space 15 is disposed between the light emitting element 12 and the wavelength converting member 16 and the inorganic material is mainly used for the binder of the wavelength converting member 16, Heat resistance against heat generated from the light emitting element can be improved, high output and high brightness can be achieved, and miniaturization can be achieved. Further, since the binder of the wavelength converting member 16 is obtained by a reaction at room temperature or a heat treatment at a temperature of 500 DEG C or lower, deterioration of the characteristics of the phosphor material that can be formed even at a low temperature and deteriorates at high temperatures can be suppressed .

Further, the wavelength converting member 16 is formed by applying the raw material mixture containing the phosphor material and the binder raw material to one surface of the forming substrate 17, reacting the raw material of the binder at room temperature, or heat- Can be easily formed at low temperature by bonding to the forming substrate.

(Example)

(Fabrication of Light-Emitting Device of Examples 1 to 4)

First, a phosphor mixture, a binder raw material, a filler and a diluting solvent were mixed to prepare a raw material mixture. As the phosphor material, phosphor particles made of Y ₃ Al ₅ O ₁₂ : Ce and phosphor particles made of CaSrS: Eu having an average particle diameter of about 15 μm were used. As the binder raw material, ethyl silicate in Example 1, perhydro polysilazane in Example 2, hydrate of sodium silicate in Example 3, or ultrafine particle powder of silica or amorphous silica in Example 4 was suspended in a solvent Respectively. As the filler, silicon dioxide particles having an average particle size of about 15 mu m were used. As the diluting solvent, terpineol was used. Subsequently, the prepared raw material mixture was printed on one surface of the formed base material 17 made of a transparent glass plate so as to have a required thickness. The diluted solvent was then removed by drying at 150 < 0 > C. Each of the wavelength converting members 16 thus obtained was used to fabricate the light emitting device 10 as shown in Fig. As the light emitting element 12, a blue LED was used.

(Fabrication of Light-emitting Device of Comparative Example 1)

As a comparative example 1, a silicone resin was used in place of the silicon oxide precursor, and a phosphor material and a silicone resin were mixed and coated on one side of the formed substrate by printing and then dried to form a wavelength converting member. 1 to 4 were fabricated.

(Evaluation Method 1)

The wavelength conversion member 16 produced in Examples 1 to 4 and Comparative Example 1 was subjected to an exposure test under a high temperature and high humidity environment of 85 DEG C and 85% RH to change the luminance (luminance) Respectively. The results of Example 1 and Comparative Example 1 are shown in Fig. In Fig. 2, the vertical axis is a relative luminance value when each initial luminance is 100. The definition of the luminance is set to the value of the peak height of the optical spectrum after being excited by the blue LED and wavelength-converted by the wavelength conversion member 16. The results of Example 1 are shown in FIG. 2, but the same results are obtained for Examples 2 to 4 as well.

(Evaluation result 1)

In Examples 1 to 4, the luminance was maintained at 95% or more even after 2000 hours. In Comparative Example 1, however, the luminance retention rate gradually decreased from 20 hours after the start of the test, and the luminance retention rate decreased to 83% Respectively.

(Evaluation Method 2)

The wavelength converting member 16 of each of Examples 1 to 4 and Comparative Example 1 was heated by an air oven and subjected to a dry high temperature environmental exposure test from 100 占 폚 to 500 占 폚 to examine changes with time in luminance. In addition, since there is a possibility that the wavelength converting member 16 is broken in a high temperature region exceeding 200 캜, visual confirmation is also made with the naked eye. Exposure time of each temperature was 24 hours, and long-term exposure was performed up to 2000 hours at only 150 DEG C and 200 DEG C near the upper limit of the practical temperature range. The results of Example 1 and Comparative Example 1 are shown in Fig. 3 to Fig. 5. Fig. 3 shows the relationship between the exposure temperature and the luminescence brightness after 24 hours exposure, Fig. 4 shows the result of exposure test at 150 deg. C in a dry high temperature environment, Fig. It is the result of the test. 3 to 5, the vertical axis is a relative luminance value when the initial luminance is 100. 3 to 5 representatively represent the results of Example 1, but the same results were obtained for Examples 2 to 4 as well.

(Evaluation result 2)

As shown in Fig. 3, in the 24-hour exposure test at each temperature, in the comparative example 1, the luminance retention rate decreased as the temperature increased, and when the temperature was 300 ° C or higher, . On the other hand, in Examples 1 to 4, there was no change in appearance, and no decrease in luminance retention was observed.

As shown in Figs. 4 and 5, in the long-term exposure test up to 1000 hours at 150 占 폚 and 200 占 폚, no change was observed in both of 150 占 폚 and 200 占 폚 in Examples 1 to 4, , The luminance retention rate was gradually decreased after 50 hours at 150 DEG C, the luminance retention rate was decreased to 87% after 2000 hours, and the luminance retention rate tended to decrease after 10 hours at 200 DEG C, When the appearance was confirmed at a point of time after 1200 hours, the wavelength converting member was finely peeled off according to the chemical change caused by the heat.

(Examples 5 to 40 and Comparative Examples 2 to 7)

First, a raw material mixture was prepared by mixing the phosphor material, the binder raw material, the diluting solvent and, if necessary, the filler. The material of the phosphor particles of the phosphor material in each of the examples and comparative examples, the average particle diameter (particle size) of the phosphor particles, the additive amount, the material of the coat layer, the material of the filler, the average particle diameter The materials and the addition amounts are shown in Tables 1 to 4. As the phosphor material, both of the phosphor material A and the phosphor material B or either one of them was used. The phosphor material A does not form a coating layer on the phosphor particles, and the phosphor material B forms a coating layer on the phosphor particles as the case may be. Α-terpineol was used as a diluting solvent.

Subsequently, the prepared raw material mixture was applied to one surface of the formed base material 17 made of a glass plate, and the raw materials of the binder were reacted at a heat treatment or room temperature to obtain a wavelength conversion member 16 having a predetermined thickness. Tables 2 and 4 show the application method of the raw material mixture, the heat treatment temperature and the thickness of the wavelength converting member 16 in each of the examples and comparative examples. The thickness of the wavelength converting member 16 is the thickness after the heat treatment or the reaction at room temperature.

[Table 1]

[Table 2]

[Table 3]

[Table 4]

For each wavelength converting member 16 thus obtained, the initial light emission luminance was examined as an initial characteristic. Further, as a high temperature and high humidity test, an exposure test was conducted under a high temperature and high humidity environment of 85 DEG C and 85% RH, and the rate of decrease in luminescence brightness after 2000 hours was examined. Further, as a dry high-temperature test, an exposure test was conducted under a dry high-temperature environment of 150 ° C or 200 ° C, and the rate of decrease in luminescence brightness after 2000 hours was examined. The light emission luminances of the respective wavelength converting members 16 are obtained by forming each wavelength converting member 16 in the light emitting device 10 as shown in Fig. 1, irradiating excitation light from a 300 W blue LED element, Was measured with a power meter. The distance between the wavelength conversion member 16 and the light emitting element 12 was set at 10 mm.

The obtained results are shown in Tables 5 and 6. In Tables 5 and 6, the luminescence brightness of the initial characteristics is the relative luminescence brightness when the luminescence brightness of Example 14 is taken as 100. The rate of decrease of the luminescence brightness in the high-temperature high-humidity test and the dry high-temperature test is a rate of decrease from the luminescence brightness of the initial characteristics in the respective Examples and Comparative Examples.

[Table 5]

[Table 6]

As shown in Tables 5 and 6, according to this embodiment, the relative luminescence brightness as the initial characteristic was 80% or more, but was as low as 70% or less in Comparative Examples 3 to 7 which were heat-treated at 550 占 폚 or more. In Comparative Example 2 using a silicone resin, the rate of decrease in luminescence brightness in the high temperature and high humidity test was 15%, the rate of decrease in luminescence brightness in the high temperature drying test at 150 占 폚 was 12% The wavelength converting member was peeled off, and the rate of decrease in the light emission luminance after 1000 hours was 33%. On the other hand, according to this example, in both the high temperature and high humidity test, the high temperature drying test at 150 占 폚 and the dry high temperature test at 200 占 폚, the light emission luminance lowering rate could be remarkably improved to 3% or less.

The wavelength conversion member 16 of Example 5 and Comparative Example 2 was changed again to a distance of 1 mm, 2 mm, 5 mm or 10 mm between the wavelength conversion member 16 and the light emitting element 12, Emitting device 10 as shown in FIG. 5A was fabricated. After the light-emitting device 10 was continuously lighted for 5000 hours, the rate of decrease of the relative light emission luminance from the light emission luminance of the initial characteristic was examined. The obtained results are shown in Table 7.

[Table 7]

As shown in Table 7, according to Example 5, even when the distance between the wavelength converting member 16 and the light emitting element 12 was 1 mm, the relative luminance drop rate was 2%, whereas in Comparative Example 2, The relative light emission luminance lowering rate could not be lower than 2%.

(theorem)

From the above results, it was found that heat resistance can be greatly improved by the present embodiment.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments and can be modified in various ways. For example, although the structure of the light emitting device 10 has been described in detail in the above embodiment, other structures may be provided. In the above embodiment, the case where the wavelength conversion member 16 is formed on one surface of the base material 17 is described. However, the wavelength conversion member 16 may be formed by other methods. For example, the wavelength conversion member 16 may be formed by putting the raw material mixture into a frame of a desired shape and oxidizing it, and the wavelength conversion member 16 may be taken out from the frame.

And can be used for a light emitting device such as an LED or an LD.

10: Light emitting device
11: substrate
12: Light emitting element
13: Wire
14: Reflector frame
15: Space
16: wavelength conversion member
17: forming substrate

Claims (14)

There is provided a light-emitting device comprising a light-emitting element and a wavelength conversion member (wavelength conversion member) disposed with a space therebetween,
Wherein the wavelength converting member comprises a phosphor material in the form of a particle and a binder,
The binder may be prepared by reacting a binder raw material containing at least one kind selected from the group consisting of an oxide precursor which becomes an oxide by hydrolysis or oxidation, a silicate compound, silica and amorphous silica at room temperature, Lt; RTI ID = 0.0 >%< / RTI >
The method according to claim 1,
Wherein the wavelength converting member is formed by applying a raw material mixture containing the phosphor material and the binder raw material to one surface of a forming base material and reacting the raw material of the binder at a room temperature, In the light emitting device.
The method according to claim 1,
The binder is obtained by reacting a binder raw material containing at least one of the group consisting of a silicon oxide precursor, a silicate compound, silica and amorphous silica which becomes silicon oxide by hydrolysis or oxidation at room temperature, In the light emitting device.
The method according to claim 1,
Wherein the phosphor material comprises phosphor particles, and the average particle diameter of the phosphor particles is 5 占 퐉 to 20 占 퐉.
The method according to claim 1,
Wherein a thickness of the wavelength converting member is 30 占 퐉 or more and 1 mm or less.
The method according to claim 1,
Wherein the wavelength conversion member has a thickness of 50 占 퐉 or more and 200 占 퐉 or less.
The method according to claim 1,
Wherein the wavelength converting member is formed by applying a raw material mixture containing the phosphor material and the binder raw material to one surface of a forming base by a printing method and reacting the raw material of the binder at a room temperature or by heat- Emitting device.
The method according to claim 1,
Wherein a distance between the light emitting element and the wavelength converting member is 1 mm or more.
The method according to claim 1,
Wherein a distance between the light emitting element and the wavelength converting member is 2 mm or more and 50 mm or less.
The method according to claim 1,
Wherein the phosphor material comprises phosphor particles, and a coating layer is formed on the surface of the phosphor particles.
11. The method of claim 10,
Wherein the coating layer comprises yttrium oxide.
The method according to claim 1,
Wherein the wavelength conversion member further comprises a filler.
13. The method of claim 12,
Wherein the filler is a material which is homogeneous with the binder.
13. The method of claim 12,
And the average particle diameter of the filler is 10 占 퐉 to 20 占 퐉.

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