JP2004343070A - Light emitting device and lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture a light emitting device with high luminance by adjusting percentage of fluorescent substances of three primary colors and a transparent resin, and thickness of a fluorescent layer formed by mixing the fluorescent substances of three primary colors into the transparent resin. <P>SOLUTION: The light emitting device comprises: a light emitting element 5 whose emission wavelength is 300-400 nm, and the transparent resin, formed by mixing particles of Y<SB>2</SB>O<SB>2</SB>S: Eu, particles of ZnS: Cu, Al, and particles of BaMgAl<SB>10</SB>O<SB>12</SB>: Eu, provided so as to cover the light emitting element 5. When total amount of each particle is made 100 pts.wt., the transparent resin is 80-150 pts.wt. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a light emitting device and a lighting device that convert light emitted from a light emitting element such as a light emitting diode into a wavelength by using a phosphor and radiate the light to the outside.

  FIG. 7 shows a conventional light emitting device for housing a light emitting element 105 such as a light emitting diode (LED). As shown in FIG. 7, the light emitting device has a light emitting element 105 mounted in the center of the upper surface, and leads for electrically conducting connection between the light emitting element 105 and the inside and outside of a light emitting element housing package (hereinafter also simply referred to as a package). A base 101 made of an insulator on which a wiring conductor (not shown) made up of a terminal, a metallized wiring layer, and the like is formed, and a through-hole for adhering and fixing to the upper surface of the base 101 and for accommodating the light emitting element 105 in the center portion is provided. It is mainly composed of the formed frame 102 made of metal, resin, ceramics or the like.

  The substrate 101 is made of a ceramic such as an aluminum oxide sintered body (alumina ceramic), an aluminum nitride sintered body, a mullite sintered body, a glass ceramic, or a resin such as an epoxy resin. When the base 101 is made of ceramics, a metallized wiring layer is formed on the upper surface by firing a metal paste made of tungsten (W), molybdenum (Mo) -manganese (Mn) or the like at a high temperature. When the base 101 is made of a resin, a lead terminal made of copper (Cu) or an iron (Fe) -nickel (Ni) alloy or the like has one end projecting into the base 101 when the base 101 is molded. To be fixed.

  The frame body 102 is made of a metal such as an aluminum (Al) or Fe-Ni-cobalt (Co) alloy, a ceramic such as an alumina sintered body, or a resin such as an epoxy resin, and is formed by cutting, molding or extrusion. It is formed by a molding technique such as molding. Further, a through hole is formed in the center of the frame body 102 and extends outward as it goes upward. When the reflectivity of light on the inner peripheral surface of the through hole is to be improved, the inner peripheral surface is made of Al or the like. Is deposited by vapor deposition or plating. Then, the frame body 102 is joined to the upper surface of the base body 101 by a solder, a brazing material such as silver brazing, or a resin adhesive.

  Then, a wiring conductor (not shown) formed on the surface of the base 101 and an electrode of the light emitting element 105 are electrically connected via a bonding wire (not shown). After forming the layer 103, the inside of the frame 102 is filled with the transparent resin 106 and thermally cured, so that the light from the light emitting element 105 is converted in wavelength by the phosphor layer 104 and light having a desired wavelength spectrum can be extracted. Can be made with equipment. Then, a light-transmitting lid 103 is joined to the upper surface of the frame 102 with solder, a resin adhesive, or the like, to form a light emitting device. Also, a light emitting element 105 having an emission wavelength including an ultraviolet region of 300 to 400 nm is selected, and the color tone is adjusted by adjusting the mixture ratio of the three primary color phosphors of red, blue, and green contained in the phosphor layer 104. Can be designed freely.

Various materials are used as such a phosphor. For example, red is Y ₂ O ₂ S: Eu (Eu-doped Y ₂ O ₂ S) particles, green is ZnS: Cu, Al particles, and blue is BaMgAl ₁₀ O ₁₂ : Eu particles are used.

In general, the phosphor is a powder, and since it is difficult to form the phosphor layer 103 using the phosphor alone, the phosphor is mixed into a transparent material such as resin or glass and applied to the surface of the light emitting element 105 to form the phosphor. Generally, the body layer 104 is used.
JP 2003-37298 A

  However, there is a strong relationship between the kneading ratio of the phosphor and the transparent material and the luminance of the light emitting device, and the thickness of the phosphor layer 104 and the luminance of the light emitting device, and the kneading ratio and the thickness of the phosphor layer 104 change. There is a problem that the luminance varies greatly between the light emitting devices.

  That is, as shown in FIG. 3, when the ratio of the transparent material to the phosphor particles 10 is small, the phosphor particles 10 aggregate, and as a result, the fluorescence 11 excited by the light 12 from the light emitting element is generated. There is a problem that the brightness is reduced because the phosphor 10a that does not emit light is not radiated to the outside because it is blocked.

  Further, as shown in FIG. 4, when the ratio of the transparent material to the phosphor particles 13 is large, the transparent material enters between the phosphor particles 13 and the light 14 from the light emitting element hits the phosphor particles 13. However, there is a problem in that the light 14a is transmitted through the transparent material, and as a result, the brightness of the light emitting device is reduced.

  Further, as shown in FIG. 5, when the thickness of the phosphor layer is small, the light 16 of the light emitting element that also leaks from the gap between the phosphor particles 15 increases, and as a result, the light that is not wavelength-converted by the phosphor particles 15 There was a problem that 16a was generated and the luminance of the light emitting device was reduced.

  Further, as shown in FIG. 6, when the thickness of the phosphor layer is large, the phosphor particles 17 spatially overlap, and the phosphor particles 17a in which the fluorescence 19 excited by the light 18 from the light emitting element overlaps. And the brightness of the light emitting device is reduced.

  Accordingly, the present invention has been completed in view of the above-mentioned conventional problems, and its object is to mix the three primary color phosphors with the transparent resin and the ratio of the three primary color phosphors to the transparent resin. By adjusting the thickness of the phosphor layer, a light-emitting device with high luminance can be manufactured, and a variation in luminance between the light-emitting devices is reduced.

The light emitting device of the present invention, a light emitting element emission wavelength is 300 to 400 nm, provided so as to cover the light-emitting _element, Y ₂ O ₂ S: Eu particles, ZnS: Cu, Al particles and BaMgAl ₁₀ O ₁₂ : a transparent resin obtained by mixing particles of Eu, wherein the transparent resin is 80 to 150 parts by mass when the total amount of the respective particles is 100 parts by mass. .

  In the light emitting device according to the present invention, preferably, the transparent resin has a thickness of 0.1 to 0.3 mm.

  The lighting device according to the present invention is characterized in that the light emitting device according to the present invention is installed in a predetermined arrangement.

The light emitting device of the present invention, a light emitting element emission wavelength is 300 to 400 nm, provided so as to cover the light emitting _element, Y ₂ O ₂ S: Eu particles, ZnS: Cu, Al particles and BaMgAl ₁₀ O ₁₂ : a transparent resin mixed with Eu particles, and when the total amount of each particle is 100 parts by mass, the transparent resin is 80 to 150 parts by mass. Thus, the fluorescence generated by the excitation of the phosphor particles is prevented from being blocked by other particles, and the fluorescence can be efficiently extracted to the outside. As a result, the luminance of the light-emitting devices can be increased, and variation in luminance between the light-emitting devices can be suppressed.

  In the light emitting device of the present invention, preferably, since the transparent resin has a thickness of 0.1 to 0.3 mm, the fluorescent particles generated by the excitation of the phosphor particles by light from the light emitting element are blocked by other particles. In addition, it is possible to effectively prevent the light of the light emitting element from passing through the phosphor particles without exciting the particles. As a result, it is possible to further increase the luminance of the light emitting devices and to further suppress the luminance variation between the light emitting devices.

  Since the lighting device of the present invention uses the light-emitting device of the present invention so as to be arranged in a predetermined arrangement, it utilizes light emission by recombination of electrons of a light-emitting element made of a semiconductor. It is possible to provide a compact lighting device that can have lower power consumption and longer life than the lighting device that has been used. As a result, it is possible to suppress the fluctuation of the center wavelength of the light generated from the light emitting element, to irradiate the light with the stable radiated light intensity and the radiated light angle (light distribution) over a long period, and to irradiate the light. In this case, it is possible to provide an illumination device in which uneven color and uneven illuminance distribution are suppressed.

  In addition, the light emitting device of the present invention is installed in a predetermined arrangement as a light source, and by installing a reflection jig, an optical lens, a light diffusing plate, and the like optically designed in an arbitrary shape around these light emitting devices, Lighting device that emits light having a light distribution of

  The light emitting device of the present invention will be described in detail below. FIG. 1 is a cross-sectional view showing an embodiment of a light emitting device according to the present invention, wherein 1 is a base, 2 is a frame, 3 is a lid, 4 is a phosphor layer, 5 is a light emitting element, and 6 is a resin. And a transparent member such as glass. The light emitting device is mainly composed of these.

The light emitting device of the present invention, a light emitting element emission wavelength is 300 to 400 nm, provided so as to cover the light emitting _element, Y ₂ O ₂ S: Eu particles, ZnS: Cu, Al particles and BaMgAl ₁₀ O ₁₂ : a transparent resin containing particles of Eu mixed therein, and when the total amount of each particle is 100 parts by mass, the transparent resin is 80 to 150 parts by mass.

  This prevents the fluorescent particles generated by the excitation of the phosphor particles by the light from the light emitting element 5 from being blocked by other particles, so that the fluorescent light can be efficiently extracted to the outside. That is, as shown in the conceptual diagram of the operation of the present invention in FIG. 2, the phosphor particles 7 are arranged in a direction perpendicular to the optical axis direction of the light 8 of the light emitting element 5 in the transparent resin layer as the phosphor layer. In the direction of the phosphor layer (in the plane direction of the phosphor layer), it is relatively dense, and in the optical axis direction of the light 8, it is relatively thin and dispersed so as not to overlap. As a result, the light 8 can efficiently hit the individual particles 7 and efficiently excite the particles 7 to be converted into light 9 having a desired wavelength. As a result, a light-emitting device with high luminance and small variation can be obtained.

  The base 1 in the present invention is an insulator made of a ceramic such as an aluminum oxide sintered body (alumina ceramic), an aluminum nitride sintered body, a mullite sintered body, a glass ceramic, or a resin such as an epoxy resin. It is a supporting member for supporting the light emitting element 5 having an emission wavelength of 300 to 400 nm.

  A metallized wiring layer made of a metal powder of W, Mo, Mn or the like for electrically connecting the inside and outside of the light emitting device is formed on the surface or inside of the base 1, and the lower surface of the base 1 or the like is formed. A lead terminal made of a metal such as a Cu or Fe-Ni alloy is joined to the metallized wiring layer on the surface exposed to the outside of the device. A light emitting element 5 having an emission wavelength of 300 to 400 nm, such as an LED, is formed on the base 1 by soldering, a resin adhesive, or silver (Ag) -epoxy resin (Ag paste) obtained by mixing a metal powder such as silver into a resin. Are joined with the joining material. Then, the electrode of the light emitting element 5 is electrically connected to the metallized wiring layer of the base 1 via a bonding wire (not shown).

  Preferably, a metal having excellent corrosion resistance, such as Ni or gold (Au), having a thickness of about 1 to 20 μm is applied to the exposed surface of the metallized wiring layer to effectively prevent the metallized wiring layer from being oxidized and corroded. In addition to this, the connection between the metallized wiring layer and the light emitting element 5 and the connection between the metallized wiring layer and the bonding wire can be strengthened. Therefore, a Ni plating layer having a thickness of about 1 to 10 μm and an Au plating layer having a thickness of about 0.1 to 3 μm are sequentially deposited on the exposed surface of the metallized wiring layer by an electrolytic plating method or an electroless plating method. Is more preferred.

  In addition, the upper surface of the substrate 1 is not electrically short-circuited to the metallized wiring layer in order to effectively suppress transmission of light to the lower surface side of the substrate 1 and efficiently reflect light to the upper side of the substrate 1. Thus, it is preferable to form a metal such as Al, Ag, Au, Pt, and Cu as a reflective layer by a vapor deposition method or a plating method.

Next, in order to convert light of the light emitting element 5 having an emission wavelength of 300 to 400 nm into light of a desired wavelength (for example, visible light of 420 to 780 nm), phosphor particles are mixed into the surface of the light emitting element 5. The phosphor layer 4 made of the transparent resin thus formed is applied and formed. The phosphor particles include Y ₂ O ₂ S: Eu which emits red (about 580 to 780 nm) fluorescence, ZnS: Cu, Al which emits green (about 450 to 650 nm) fluorescence, and blue (420 to 550 nm). BaMgAl ₁₀ O ₁₂ : Eu which generates the fluorescence of (1).

  Since these phosphors are powders and it is difficult to form only the phosphor on the surface of the light emitting element 5, phosphor particles are mixed in a transparent resin and applied to the surface of the light emitting element 5 to form a phosphor layer. 4 is assumed. The transparent resin is made of an epoxy resin, a silicone resin, an acrylic resin, or the like.

  The light emitting element 5 having an emission wavelength of 300 to 400 nm generates light in a wavelength band mainly including an ultraviolet region, and the phosphor particles efficiently convert the light in this wavelength band into fluorescent light. be able to.

In the present invention, when the total amount of Y ₂ O ₂ S: Eu particles, ZnS: Cu, Al particles and BaMgAl ₁₀ O ₁₂ : Eu particles is 100 parts by mass, the transparent resin is 80 to 150 parts by mass. When the amount of the transparent resin is less than 80 parts by mass, the phosphor particles aggregate in the phosphor layer 4, and the phosphor generated by excitation of the phosphor by the light of the light emitting element 5 emits light. The light-emitting device is likely to be blocked by the non-existing phosphor, and the brightness of the light-emitting device is reduced. On the other hand, when the amount exceeds 150 parts by mass, the amount of the transparent resin in the phosphor layer 4 is too large, and a large amount of light of the light-emitting element 5 that passes through the transparent resin without hitting the phosphor particles is generated, As a result, the brightness of the light emitting device is reduced.

Further, the Y ₂ O ₂ S: Eu particles preferably account for 80 to 90% by mass. If the amount is less than 80% by mass, the intensity of red (about 580 to 780 nm) fluorescent light tends to decrease, and as a result, the luminance of the entire fluorescent light tends to decrease. If the amount exceeds 90% by mass, the intensity of the red (about 580 to 780 nm) fluorescent light becomes too strong, and as a result, the luminance of the entire fluorescent light tends to decrease.

  The ZnS: Cu, Al particles are preferably 3 to 5% by mass. If the amount is less than 3% by mass, the intensity of green (about 450 to 650 nm) fluorescent light is too strong, and the overall luminance of the fluorescent light is likely to decrease. If the amount exceeds 5% by mass, the intensity of green (about 450 to 650 nm) fluorescent light becomes too strong, and as a result, the overall luminance of the fluorescent light tends to decrease.

BaMgAl ₁₀ O _12: Eu particles is preferably from 5 to 17% parts by weight. If the amount is less than 5% by mass, the intensity of the blue (420 to 550 nm) fluorescent light is reduced, and as a result, the luminance of the entire fluorescent light is likely to be reduced. When the content exceeds 17% by mass, the intensity of blue (420 to 550 nm) fluorescent light becomes too strong, and as a result, the luminance of the entire fluorescent light tends to decrease.

  In the present invention, the transparent resin preferably has a thickness of 0.1 to 0.3 mm. When the thickness of the transparent resin is less than 0.1 mm, light leaks from between the particles of the phosphor, and the efficiency of converting the light of the light emitting element 5 into desired light decreases. Further, when the thickness of the transparent resin exceeds 0.3 mm, the phosphor particles easily overlap in the optical axis direction of the light of the light emitting element 5, and as a result, the phosphor is excited by the light of the light emitting element 5 and generated. Fluorescent light is easily blocked by a phosphor that does not emit light, and the luminance of the light emitting device is easily reduced.

  In the light emitting device of the present invention, the light emitting element 5 is mounted on the mounting portion of the base 1 on which the light emitting element 5 is mounted, and the light emitting element 5 is electrically connected to an external external electric circuit via a bonding wire and a metallized wiring layer. The frame 2 is joined to the periphery of the mounting portion of the light emitting element 5 on the upper surface of the frame 1 by a resin adhesive, solder, or the like, and the inside of the frame 2 is filled with a transparent member 6 such as glass or transparent resin. It is manufactured by joining a light-transmitting lid 3 to the upper surface of the substrate 2 with a resin adhesive, solder, or the like.

  The frame 2 is made of a ceramic such as an aluminum oxide sintered body (alumina ceramics), an aluminum nitride sintered body, a mullite sintered body, a glass ceramic, or an insulator made of a resin such as an epoxy resin. It is made of metal such as Cu, Ag, Fe-Ni-Co alloy, Fe-Ni alloy, stainless steel and brass.

  The lid 3 is made of a light-transmitting material such as glass, sapphire, quartz, or a resin (plastic) such as epoxy resin, silicone resin, or acrylic resin. The light-emitting element 5 and metallized wiring disposed inside the frame 2 are provided. In addition to protecting the layers, the bonding wires, and the transparent member 6, the inside of the light emitting element housing package is hermetically sealed. Further, by forming the lid 3 into a lens shape and adding the function of an optical lens, it is possible to condense or disperse the fluorescent light and take out the fluorescent light with a desired emission angle and intensity distribution.

  Further, the light emitting device of the present invention is obtained by installing one light emitting device in a predetermined arrangement, or by forming a plurality of light emitting devices, for example, in a lattice shape, a staggered shape, a radial shape, or a circular shape including a plurality of light emitting devices. By arranging a plurality of light emitting device groups in a predetermined arrangement, such as a group in which a plurality of light emitting device groups having a polygonal shape are formed concentrically, a lighting device can be obtained. Accordingly, since the light emission by the recombination of the electrons of the semiconductor light emitting element 5 is used, it is possible to achieve lower power consumption and longer life than the conventional lighting device using discharge, and to generate less heat. A small lighting device can be obtained. As a result, the fluctuation of the center wavelength of the light generated from the light emitting element 5 can be suppressed, and the light can be radiated at a stable radiated light intensity and a radiated light angle (light distribution) over a long period of time. It is possible to provide an illuminating device in which uneven color and uneven illuminance distribution on the surface are suppressed.

  Further, by installing a plurality of light emitting devices of the present invention in a predetermined arrangement as a light source, and by installing a reflection jig, an optical lens, a light diffusion plate and the like optically designed in an arbitrary shape around these light emitting devices. The lighting device can emit light having an arbitrary light distribution.

  For example, a plurality of light emitting devices 21 are arranged in a plurality of rows on a light emitting device driving circuit board 23 as shown in the plan view and the sectional view shown in FIGS. In the case of a lighting device in which the reflection jig 22 is provided, in a plurality of light emitting devices 21 arranged in one row adjacent to each other, an arrangement in which the interval between adjacent light emitting devices 21 is not shortest, that is, a so-called staggered shape. It is preferable that That is, when the light-emitting devices 21 are arranged in a grid, the light-emitting devices 21 serving as a light source are arranged in a straight line, thereby increasing the glare. Accordingly, discomfort and eye disorders are more likely to occur. On the other hand, the staggered arrangement suppresses glare and reduces human discomfort and eye disorders. Further, since the distance between the adjacent light-emitting devices 21 is increased, thermal interference between the adjacent light-emitting devices 21 is effectively suppressed, and heat transfer in the light-emitting device drive circuit board 23 on which the light-emitting devices 21 are mounted is performed. The stagnation is suppressed, and heat is efficiently radiated to the outside of the light emitting device 21. As a result, a long-life lighting device with stable optical characteristics for a long period of time with little obstacle to human eyes can be manufactured.

  In addition, the lighting device is configured such that a group of circular or polygonal light emitting devices 21 including a plurality of light emitting devices 21 is concentrically arranged on a light emitting device driving circuit board 23 as shown in the plan view and the sectional view shown in FIGS. In the case of a lighting device in which a plurality of light emitting devices 21 are formed, it is preferable that the number of light emitting devices 21 arranged in one circular or polygonal light emitting device group 21 be larger on the outer peripheral side than on the center side of the lighting device. Accordingly, more light emitting devices 21 can be arranged while maintaining a proper interval between the light emitting devices 21, and the illuminance of the lighting device can be further improved. In addition, the density of the light emitting device 21 in the central portion of the lighting device can be reduced to suppress the accumulation of heat in the central portion of the light emitting device driving circuit board 23. Therefore, the temperature distribution in the light emitting device drive circuit board 23 becomes uniform, heat is efficiently transmitted to the external electric circuit board and the heat sink on which the lighting device is installed, and the temperature rise of the light emitting device 21 can be suppressed. As a result, the light-emitting device 21 can operate stably over a long period of time, and a lighting device with a long life can be manufactured.

  Such lighting devices include, for example, general lighting fixtures, chandelier lighting fixtures, residential lighting fixtures, office lighting fixtures, store fixtures, exhibition lighting fixtures, street lighting fixtures used indoors and outdoors. Guidance light equipment and signal equipment, stage and studio lighting equipment, advertising lights, lighting poles, underwater lighting lights, strobe lights, spotlights, security lights embedded in telephone poles, etc., emergency lighting equipment, flashlights, Examples include an electric bulletin board, a dimmer, an automatic blinker, a backlight such as a display, a moving image device, a decorative article, an illuminated switch, an optical sensor, a medical light, a vehicle light, and the like.

  An embodiment of the light emitting device of the present invention will be described below.

(Example 1)
Using a gallium nitride semiconductor light emitting device having a main emission peak of 382 nm as the light emitting device 5, a light emitting device of the present invention was manufactured as follows.

A substrate 1 made of alumina ceramics, a frame 2 made of aluminum, a lid 3 made of epoxy resin, and a transparent member 6 made of silicone resin are used. Phosphor particles contained in the phosphor layer 4 are as follows. , Y ₂ O ₂ S: Eu particles, ZnS: Cu, Al particles, and BaMgAl ₁₀ O ₁₂ : Eu particles. A silicone resin was used as a transparent resin (binder) for mixing the phosphor particles.

Eu doped into Y ₂ O ₂ S: Eu particles and BaMgAl ₁₀ O ₁₂ : Eu particles has a property of absorbing ultraviolet light of 300 to 400 nm to emit fluorescence, and the wavelength of the fluorescence is mother crystals Eu is doped _{(Y 2 O 2 S, BaMgAl} 10 O 12) depending on _the case of Y 2 _{O 2} S fluoresced red (about 580～780Nm), in the case of _BaMgAl 10 _{O 12} It emits blue (420 to 550 nm) fluorescence. The doping amount of Eu is about 0.5 to 3% by mass with respect to the mother crystal.

Mixing of the phosphor particles was performed by adding ethanol to the phosphor particles, stirring the mixture for 24 hours with a mixer, and then drying the ethanol at 100 ° C. in an air atmosphere to remove the ethanol.

At this time, a sample of a transparent resin containing phosphor particles was prepared, which became the phosphor layer 4 in which the ratio of the phosphor particles to the silicone resin was five (see Table 1). Using these samples, a light emitting device having the configuration shown in FIG. 1 was manufactured, and the luminance was evaluated. Note that the thickness of the phosphor layer 4 was 0.2 mm in all light emitting devices. The luminance was measured using a spectral radiance meter (“CS-1000” manufactured by Minolta). Table 1 shows the results.

  From Table 1, it can be seen that the sample No. having 77 parts by mass of the phosphor particles and 100 parts by mass of the silicone resin. Sample No. 1 is 80 parts by mass of phosphor particles and 100 parts by mass of silicone resin. Compared with No. 2, the brightness was sharply reduced. This is probably because the amount of the silicone resin is too large with respect to the amount of the phosphor particles, so that light of the light-emitting element 5 that is transmitted without hitting the phosphor is generated, and as a result, the luminance is reduced. .

  In addition, the sample No. having 153 parts by mass of the phosphor particles and 100 parts by mass of the silicone resin. Sample No. 5 is 150 parts by mass of phosphor particles and 100 parts by mass of silicone resin. As compared with No. 4, the brightness was sharply reduced. This is because the amount of the phosphor particles with respect to the silicone resin is too large, so that the aggregation of the phosphor particles starts, and as a result, the fluorescence generated by the excitation of the phosphor particles by the light of the light emitting element 5 emits light. This is probably because the brightness was reduced by being blocked by the phosphor particles.

Sample No. 1 in which 80 parts by mass of phosphor particles and 100 parts by mass of silicone resin were used. Sample No. 2 and 150 parts by mass of phosphor particles and 100 parts by mass of silicone resin. For Sample No. 4, Sample No. 4 in which 115 parts by mass of phosphor particles and 100 parts by mass of silicone resin were used. Assuming that the luminance of No. 3 was 100%, a luminance of 95% or more was obtained. This is because the phosphor particles are relatively dense in the direction perpendicular to the optical axis direction of the light of the light emitting element 5 in the phosphor layer 4 (the surface direction of the phosphor layer 4), and relatively in the optical axis direction of the light. It is considered that the brightness was increased because the light of the light emitting element 5 efficiently hit the individual phosphor particles and efficiently excited the phosphor particles as a result of the thin and dispersed arrangement so as not to overlap.

(Example 2)
Next, in the light emitting device having the configuration shown in FIG. 1, five types of samples in which the thickness of the phosphor layer 4 was changed to five types (see Table 2) were produced. In addition, one of these is the sample No. in Table 1. 3, and the luminance was measured in the same manner as in Example 1 above. Table 2 shows the results.

  From Table 2, it can be seen that Sample No. 4 in which the thickness of the phosphor layer 4 was 0.08 mm was obtained. Sample No. 6 was a sample No. 6 in which the thickness of the phosphor layer 4 was 0.1 mm. 7, a sharp decrease in luminance was confirmed. This is presumably because light was leaked from between the phosphor particles because the thickness of the phosphor layer 4 was thin, and the efficiency of the light emitting element 5 to convert light into fluorescence was deteriorated.

  Sample No. 3 in which the thickness of the phosphor layer 4 was 0.33 mm. Sample No. 9 is Sample No. 9 in which the thickness of the phosphor layer 4 is 0.30 mm. Compared with No. 8, a sharp decrease in luminance was confirmed. This is because, since the thickness of the phosphor layer 4 is large, the phosphor particles overlap in the optical axis direction of the light emitting element 5, and the fluorescence emitted by the phosphor particles is blocked by the non-emitted phosphor particles, and the luminance is reduced. Seems to have decreased.

  Sample No. 1 in which the thickness of the phosphor layer 4 was 0.1 mm. Sample No. 7 and Sample No. 7 in which the thickness of the phosphor layer 4 was 0.3 mm. 8 is sample No. The luminance of 95% or more with respect to the luminance of 3 was obtained. This is because the phosphor particles are relatively dense in the direction perpendicular to the optical axis direction of the light of the light emitting element 5 in the phosphor layer 4 (plane direction of the phosphor layer 4), and relatively thin in the optical axis direction of the light. As a result, the light from the light emitting element 5 efficiently hit the individual phosphor particles and efficiently excited the phosphor particles. As a result, it was considered that the brightness was increased.

  It should be noted that the present invention is not limited to the above embodiments and examples, and that various changes may be made without departing from the spirit of the present invention.

  Further, the lighting device of the present invention is not limited to one in which a plurality of light emitting devices 21 are arranged in a predetermined arrangement, but may be one in which one light emitting device 21 is arranged in a predetermined arrangement.

FIG. 1 is a cross-sectional view illustrating an example of a light emitting device according to an embodiment of the present invention. FIG. 4 is a side view schematically illustrating a state of dispersion of phosphor particles in a transparent resin for explaining a fluorescence generating function of the light emitting device of the present invention. FIG. 9 is a side view schematically illustrating a state of dispersion of phosphor particles in a transparent resin for explaining a fluorescence generating function of a conventional light emitting device. FIG. 9 is a side view schematically illustrating a state of dispersion of phosphor particles in a transparent resin for explaining a fluorescence generating function of a conventional light emitting device. FIG. 9 is a side view schematically illustrating a state of dispersion of phosphor particles in a transparent resin for explaining a fluorescence generating function of a conventional light emitting device. FIG. 9 is a side view schematically illustrating a state of dispersion of phosphor particles in a transparent resin for explaining a fluorescence generating function of a conventional light emitting device. FIG. 11 is a cross-sectional view illustrating a conventional light emitting device. It is a top view showing an example of an embodiment of a lighting installation of the present invention. FIG. 9 is a cross-sectional view of the lighting device of FIG. 8. It is a top view showing other examples of an embodiment of a lighting installation of the present invention. It is sectional drawing of the lighting device of FIG.

Explanation of reference numerals

1: base 2: frame 3: lid 4: phosphor layer 5: light emitting element 6: transparent member
21: Light emitting device
22: Reflection jig
23: Light emitting device drive circuit board

Claims (3)

A light emitting element emission wavelength is 300 to 400 nm, provided so as to cover the light-emitting _element, Y ₂ O ₂ S: Eu particles, ZnS: Cu, Al particles and _BaMgAl 10 _O 12: Eu-particle A light-emitting device comprising: a transparent resin mixed with the transparent resin, wherein the transparent resin is 80 to 150 parts by mass when the total amount of the particles is 100 parts by mass. The light emitting device according to claim 1, wherein the transparent resin has a thickness of 0.1 to 0.3 mm. An illumination device, wherein the light emitting device according to claim 1 or 2 is installed in a predetermined arrangement.

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