Fluorescent wheel, wheel device, and light-emitting device

Abstract

To provide a fluorescent wheel, wheel device and light-emitting device, which allow for suppressing evenness in color of emitted fluorescence and reducing the size and weight of the light-emitting device while ensuring good cooling performance of the light-emitting device.SOLUTION: A fluorescent wheel 100 is provided, comprising a phosphor unit 10 annularly formed about the center 12 of a rotation shaft and configured to rotate about the rotation shaft to convert light of a wavelength in a specific range into light of another wavelength, and a blower unit 20 consisting of a plurality of blades 22 rotating about the rotation shaft.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fluorescent wheel, a wheel device, and a light emitting apparatus. [Background technology]

[0002] 2. Description of the Related Art Light emitting devices using wavelength conversion members that convert light emitted from a light source such as an LED or LD as a light emitting element into light of a different wavelength and emit the converted light by a layer containing phosphor particles are known.

[0003] An optical device such as a projector as a light-emitting device projects light, which is a combination of a laser light source that emits blue light, and light from the light source and fluorescent light whose wavelength has been converted by a wavelength conversion member, onto a screen or the like as an image.

[0004] A wavelength conversion member incorporated in such a light emitting device has a disk-shaped substrate and a disk-shaped or annular phosphor layer formed on one surface of the substrate.The substrate is rotated by a driving device such as a motor to continuously change the irradiation position of the light source light, thereby converting the wavelength while suppressing a local temperature rise in the phosphor layer (Patent Document 1).

[0005] Such optical devices generally have a blower or fan or other ventilation unit to cool the heat source placed inside the housing. Air is taken in through intake ports formed on the side walls or bottom of the housing, and the hot air inside the housing is expelled from the exhaust port by the exhaust unit, thereby preventing breakdowns caused by heat generated by the optical device (Patent Document 2).

[0006] Patent Document 3 discloses a technology for a semiconductor light-emitting device having a light emission surface for emitting a composite light in a predetermined direction, the technology being composed of a wiring board, a semiconductor light-emitting element arranged on the mounting surface of the wiring board, a feather-shaped wavelength conversion member containing a phosphor that absorbs at least a part of the incident light from the semiconductor light-emitting element and emits an emission light of a wavelength different from the incident light, and a support member that supports the wavelength conversion member, a blower that generates a convection current toward the semiconductor light-emitting element, a driving body that transmits a driving force to the blower and rotates the wavelength conversion member, and a housing that has an opening on the light emission surface side, surrounds the semiconductor light-emitting element and the blower, and reflects the emission light toward the light emission surface. That is, the technology described in Patent Document 3 suppresses the temperature rise of the semiconductor light-emitting element (LED chip) and the wavelength conversion member by using the rotating blade itself as a wavelength conversion member. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2004-341105 A [Patent Document 2] JP 2012-073524 A [Patent Document 3] JP 2013-211456 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, since the wavelength conversion member in Patent Document 3 has a feather-like shape tilted with respect to the rotation axis, the distance at which the light emitted from the semiconductor light emitting element is irradiated onto the rotating wavelength conversion member changes depending on the position of the wavelength conversion member, which may cause color unevenness in the emitted fluorescence.

[0009] The present invention has been made in consideration of the above circumstances, and aims to provide a fluorescent wheel, a wheel device, and a light-emitting device that can suppress unevenness in the color of the emitted fluorescent light, ensure the cooling performance of the light-emitting device, and contribute to making the light-emitting device smaller and lighter. [Means for solving the problem]

[0010] (1) In order to achieve the above object, the fluorescent wheel of the present invention employs the following means: That is, the fluorescent wheel of the application example of the present invention is a fluorescent wheel characterized by comprising: a phosphor section formed in an annular shape centered on a rotation axis, rotating about the rotation axis, and converting light of a specific range of wavelengths into light of another wavelength; and a blower section consisting of a plurality of blades rotating about the rotation axis.

[0011] This allows the fluorescent wheel and the blower fan to be integrated, and the space for the blower fan and the motor that turns it to be free, which contributes to making the light-emitting device smaller and lighter. Also, since the phosphor part is formed in a flat plate shape like the conventional one, it is possible to suppress color unevenness of the emitted fluorescent light. Also, depending on the shape of the blades, it is possible to selectively design where inside the light-emitting device the air is mainly blown, and for example, it is possible to concentrate the air on parts that generate a lot of heat, such as light-emitting elements.

[0012] (2) In addition, in the fluorescent wheel of the application example of (1) above, the phosphor section comprises a base material formed in a disk shape and a phosphor section formed in an annular shape on one main surface of the base material, the air blowing section includes an opening formed in the base material, and the multiple blades are provided in the opening of the base material at an angle with respect to the one main surface of the base material.

[0013] In this way, by providing both the phosphor section and the air blowing section on the base material, the number of parts can be reduced, leading to cost reduction.

[0014] (3) Furthermore, in the fluorescent wheel of the application example of (1) above, the plurality of blades are each formed radially outward from the center of the rotation axis, the phosphor portion is formed radially outward from the plurality of blades using a material different from the plurality of blades, and the phosphor portion and the plurality of blades rotate synchronously.

[0015] In this way, by constructing the blades and the phosphor part from different materials, freedom is gained in designing the shape of the blades. It is also possible to manufacture each part from different materials, which provides freedom in the configuration of the fluorescent wheel, such as a reflective type or a transmissive type.

[0016] (4) In the fluorescent wheel according to any one of the application examples of (1) to (3) above, the air blowing section includes two or more types of blades having different outer diameters from the center of the rotation shaft.

[0017] This makes it easier to adjust the directionality and power of the airflow from the fluorescent wheel. Also, depending on the combination of blade shapes, it is possible to generate highly linear or highly diffused airflow. In addition, because multiple types of blades rotate on one rotating shaft, this contributes to making the light-emitting device smaller and lighter than when multiple types of blades are used as multiple air-blowing fans.

[0018] (5) In addition, in the fluorescent wheel of any of the application examples of (1) to (4) above, the blowing section is characterized by having a cover that covers the front surface of the plurality of blades in the axial direction of the rotation shaft.

[0019] This makes it possible to prevent foreign objects from getting into the blades. Also, by making only a part of the cover an opening, it is possible to control the airflow direction.

[0020] (6) In the fluorescent wheel according to the application example of (5) above, the cover is characterized by having a plurality of ribs extending in a curved shape from the center of the rotation shaft toward the outside in the radial direction.

[0021] This makes it possible to create a constant flow of air within the housing of the light emitting device, making it easier to efficiently blow air even in areas away from the fluorescent wheel.

[0022] (7) Furthermore, a wheel device of an application example of the present invention is a wheel device used in a light emitting device, and is characterized in that it comprises a fluorescent wheel described in any one of (1) to (6) above and a motor that rotates the fluorescent wheel.

[0023] This makes it possible to configure a wheel device using a fluorescent wheel having a blowing section.

[0024] (8) Furthermore, a light emitting device according to an embodiment of the present invention includes a light source that emits light having a wavelength in the specific range, The present invention is characterized by comprising the wheel device described in (7) above, on which light of the specific range of wavelengths is irradiated from the light source, a display device for displaying an image, and a projection optical system for projecting the image displayed on the display device to the outside using the light emitted from the wheel device.

[0025] This makes it possible to configure a light-emitting device using a fluorescent wheel with an air blowing unit, thereby making it possible to reduce the weight of the entire light-emitting device while maintaining the cooling function of the light-emitting device. Such a light-emitting device can be applied to projectors and the like that use a rotating fluorescent wheel. Effect of the Invention

[0026] According to the present invention, it is possible to configure a fluorescent wheel, a wheel device, and a light emitting device that can suppress unevenness in the color of the emitted fluorescent light, ensure the cooling performance of the light emitting device, and contribute to making the light emitting device smaller and lighter. [Brief description of the drawings]

[0027] [Figure 1] 1A and 1B are a plan view and a cross-sectional view, respectively, that diagrammatically show an example of a fluorescent wheel according to a first embodiment. [Diagram 2]1A and 1B are a plan view and a cross-sectional view, respectively, that diagrammatically show a modified example of the fluorescent wheel according to the first embodiment. [Diagram 3] 1A and 1B are a plan view and a cross-sectional view, respectively, that diagrammatically show a modified example of the fluorescent wheel according to the first embodiment. [Figure 4] 2 is an enlarged schematic diagram of a cross section of a phosphor portion of a fluorescent wheel. FIG. [Diagram 5] 11A and 11B are a plan view and a cross-sectional view, respectively, that diagrammatically show an example of a fluorescent wheel according to a second embodiment. [Figure 6] 13A and 13B are a plan view and a cross-sectional view, respectively, that diagrammatically show a modified example of the fluorescent wheel according to the second embodiment. [Figure 7] 13A and 13B are a plan view and a cross-sectional view, respectively, that diagrammatically show a modified example of the fluorescent wheel according to the second embodiment. [Figure 8] FIG. 11 is a plan view illustrating a schematic diagram of a modified example of the fluorescent wheel according to the second embodiment. [Figure 9] 13A and 13B are plan views each showing a schematic diagram of a modified example of the cover of the fluorescent wheel. [Figure 10] FIG. 1 is a schematic diagram illustrating an example of a wheel device of the present invention. [Figure 11] FIG. 2 is a conceptual diagram illustrating an example of a portion of a light emitting device of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Next, an embodiment of the present invention will be described with reference to the drawings. In order to facilitate understanding of the description, the same reference numerals are used for the same components in each drawing, and duplicated descriptions will be omitted. In the configuration diagrams, the size of each component is conceptually shown, and does not necessarily represent the actual dimensional ratio.

[0029] [Fluorescent wheel configuration] (First embodiment) 1(a) and 1(b) are respectively a plan view and a cross-sectional view that show a schematic example of a fluorescent wheel 100 according to the first embodiment. FIG. 1(b) shows a cross section taken along line AA in FIG. 1(a), but does not show the blades 22 in cross section. The cross-sectional views of the fluorescent wheel 100 in FIG. 2 and subsequent figures are similar. The fluorescent wheel 100 according to this embodiment includes a phosphor section 10 that is formed in an annular shape centered on a center 12 of a rotation axis, rotates about the rotation axis, and converts light of a specific range of wavelengths into light of another wavelength, and a blower section 20 that is made up of a plurality of blades 22 that rotate about the rotation axis.

[0030] This allows the fluorescent wheel 100 and the blower unit 20, which serves as a blower fan, to be constructed as an integrated unit, and creates space for the blower fan and the motor that drives it, which contributes to making the light-emitting device smaller and lighter. Also, since the phosphor unit 10 is formed in a flat plate shape similar to the conventional one, color unevenness in the emitted fluorescent light can be suppressed. Also, depending on the shape of the blades 22, etc., it is possible to selectively design where in the light-emitting device the air is mainly blown, and for example, it is possible to concentrate the air on parts that generate a lot of heat, such as light-emitting elements.

[0031] The fluorescent wheel 100 absorbs and excites excitation light (light source light) emitted from a light source to generate converted light of a different wavelength, and emits radiated light. For example, it can absorb blue excitation light and emit converted light different from the blue excitation light converted by the phosphor section 10, and can also reflect the blue excitation light, and convert the converted light and the excitation light together, or use only the converted light, into light of various colors.

[0032] In the fluorescent wheel 100 according to this embodiment, the phosphor section 10 is preferably composed of a base material 30 formed in a disk shape and a phosphor layer 14 formed in an annular shape on one main surface 32 of the base material 30. The air blowing section 20 preferably includes an opening 34 formed in the base material 30, and the blades 22 are preferably provided in the opening 34 of the base material 30 at an angle with respect to one main surface 32 of the base material 30. By providing both the phosphor section 10 and the air blowing section 20 on the base material 30 in this manner, the number of components constituting the light emitting device can be reduced, leading to cost reduction. The diameter of the fluorescent wheel 100 varies depending on the design of the light emitting device, but can be, for example, φ30 mm to φ150 mm.

[0033] The phosphor layer 14 is formed in a ring shape having a certain width at a predetermined distance from the center 12 of the rotation shaft. By forming the phosphor layer 14 in a ring shape, the phosphor layer 14 is formed only in the portion irradiated with the excitation light and in its vicinity, which makes it possible to reduce the weight and cost of the phosphor wheel 100. The width of the ring-shaped phosphor section 10 varies depending on the design of the light emitting device, but can be, for example, 3 mm to 10 mm.

[0034] The base material 30 is formed in a disk shape, except for the blades 22 and the openings 34. The material of the base material 30 can be metals such as aluminum, iron, copper, and alloys containing these, glass, ceramics, and the like. When making the reflective fluorescent wheel 100, the entire base material 30 can be made of a material that reflects light, but a material that does not take light reflection into consideration may be plated with a material that reflects light such as silver. In addition, since the temperature increases when high-energy light is irradiated, it is preferable that the base material 30 has high thermal conductivity. In addition, when forming the blades 22, it is preferable that the base material 30 has excellent workability. Therefore, the base material 30 is preferably made of aluminum.

[0035] The material of the blade 22 may be any material, such as metals such as aluminum, iron, copper, and alloys containing these, glass, ceramics, and plastic (resin). The blade 22 may be formed by bending a part of the base material 30 by pressing or the like when forming the opening 34 in the base material 30. The base material 30, the opening 34, and the blade 22 may also be formed by a casting method in which molten metal is poured into a mold. In this way, the base material 30 and the blade 22 are integrally formed from the same material, thereby further reducing costs. The blade 22 may be provided by joining the periphery of the opening 34 of the base material 30 by welding, adhesive, or the like. FIGS. 1(a) and (b) show an example in which the blade 22 is formed by bending a part of the base material 30.

[0036] The openings 34 are different from the holes that connect the rotating shaft. By providing the openings 34 near the blades 22, air can be taken in through the openings 34 and pushed out by the rotating blades 22, thereby ensuring a blowing function. There is no particular limit to the number of blades 22. For example, the number of blades 22 may be about 3 to 10. The blades 22 are disposed at equal angles relative to the center 12 of the rotating shaft.

[0037] 2(a) and 2(b) are respectively a plan view and a cross-sectional view that typically show a modified example of the fluorescent wheel 100 according to the first embodiment. Fig. 2(b) shows a cross section taken along line BB in Fig. 2(a). As shown in Fig. 1 or 2, the phosphor section 10 and the blower section 20 may be provided on either the inner diameter side or the outer diameter side of the base material 30.

[0038] 3(a) and (b) are respectively a plan view and a cross-sectional view that typically show a modified example of the fluorescent wheel 100 according to the first embodiment. Fig. 3(b) shows a cross section taken along line CC in Fig. 3(a). As shown in Figs. 3(a) and (b), it is preferable that the blower 20 includes two or more types of blades 22 that have different outer diameters from the center 12 of the rotation axis.

[0039] This makes it easier to adjust the directionality and wind power of the air blown from the fluorescent wheel 100. In addition, it is possible to generate a highly straight-line wind or a highly diffuse wind depending on the combination of the shapes of the blades 22. In addition, since multiple types of blades 22 are rotated on one rotation shaft, it can contribute to a smaller size and lighter weight of the light emitting device compared to a case in which multiple types of blades 22 are used as multiple blower fans. In this embodiment, two or more types of blades 22 having different outer diameters from the center 12 of the rotation shaft are all provided on one base material 30. In the example of FIG. 3, the number and the evenly spaced angle of the two types of blades 22 having different outer diameters are described as being the same, but the number of blades 22 may be different for each diameter, and the evenly spaced angle does not need to be the same.

[0040] 4 is a schematic diagram showing an enlarged cross section of the phosphor section 10 of the phosphor wheel 100. The phosphor layer 14 may be formed of phosphor particles 16 and a binder 18 having light-transmitting properties. The binder 18 bonds the phosphor particles 16 together. The phosphor layer 14 may be formed of a ceramic sintered body consisting of only phosphor particles 16, which are crystalline particles, or a mixture of phosphor particles 16, which are crystalline particles, and ceramic particles that form a transparent phase. The ceramic particles that form a transparent phase are, for example, aluminum oxide. The phosphor layer 14 may include voids.

[0041] An anti-reflection layer may be provided on the main surface of the phosphor layer 14 on the side where the excitation light is incident. Furthermore, when the fluorescent wheel 100 is of a reflective type, a reflective layer made of Al, Ag, or the like may be provided on the main surface of the phosphor layer 14 opposite the side where the excitation light is incident. The anti-reflection layer or the reflective layer may be provided by sputtering, plating, or the like. The phosphor layer 14 may be bonded to the base material 30 by a binder 18. Furthermore, the phosphor layer 14 may be bonded to the base material 30 by an adhesive such as an epoxy resin or a silicone resin.

[0042] The thickness of the phosphor layer 14 is preferably 10 μm or more and 1000 μm or less. This is because, as the phosphor layer 14 becomes thicker, the phosphor conversion occurs in a relatively wide area within the film, resulting in high luminescence intensity. If the phosphor layer 14 is too thick, problems due to heat storage increase, but this is solved by the high heat dissipation properties of the rotating wheel structure. Also, if the phosphor layer 14 is too thick, the risk of phosphor particles 16 falling off and the phosphor layer 14 peeling off increases, but if the phosphor layer 14 is 1000 μm or less, there is no problem.

[0043] The phosphor constituting the phosphor particles 16 may be, for example, an yttrium aluminum garnet phosphor (YAG phosphor) or a lutetium aluminum garnet phosphor (LAG phosphor). In addition, the phosphor may be selected from the following materials depending on the design of the color to be emitted. For example, BaMgAl 10 O 17 :Eu, ZnS:Ag,Cl,BaAl 2 S 4 :Eu or CaMgSi 2 O 6 : Blue phosphors such as Eu, Zn 2 SiO 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 Yellow, orange or red phosphors such as (M1)S:Eu or (M1)S:Eu, (Y,Gd)BO 3 :Eu,Y 2 O 2 S: Eu, (M1) 2 S 5 N 8:Eu, (M1)AlSiN 3 :Eu or YPVO 4 Examples of the red phosphor include Ba, Ca, Sr, and Mg. In the above chemical formula, M1 includes at least one of the group consisting of Ba, Ca, Sr, and Mg, M2 includes at least one of Ga and Al, and M3 includes at least one of the group consisting of Y, Gd, Lu, and Te. The above phosphors are merely examples, and the phosphors used in the phosphor wheel 100 are not necessarily limited to those mentioned above.

[0044] The average particle size of the phosphor particles 16 is preferably 10 μm or more and 60 μm or less, and more preferably 15 μm or more and 30 μm or less. By making it 10 μm or more, the luminous intensity of the converted light increases, and therefore the luminous intensity of the phosphor wheel 100 increases. In addition, since it is 60 μm or less, shedding of the phosphor particles 16 when the phosphor wheel 100 is rotated can be suppressed. In addition, the temperature of each phosphor particle 16 can be maintained low, and thermal quenching can be suppressed.

[0045] In this specification, the average particle size is the median diameter (D50) or the average particle size of particles obtained by analyzing an SEM image. The average particle size, which is the median diameter (D50), can be measured by dry measurement or wet measurement using a laser diffraction / scattering type particle size distribution measurement device. The average particle size obtained by analyzing an SEM image can be measured by the following method. An SEM image is obtained, for example, at 1000 times magnification, for a cross section perpendicular to the planar direction of the phosphor layer 14. Then, image analysis such as binarization is performed on the obtained SEM image, and the cross-sectional areas of 100 or more particles recognized as phosphor particles 16 from the image are calculated, and the average particle size can be obtained from the cumulative distribution. When calculating the cross-sectional areas of 100 or more particles recognized as phosphor particles from the image, cross-sectional images of multiple locations in the phosphor layer 14 (for example, three or more) are obtained so that the overall average particle size of the phosphor particles 16 contained in the phosphor layer 14 is obtained.

[0046] The binder 18 is made of a material having translucency. This allows the excitation light and the converted light to pass through. The binder 18 is made of, for example, alumina (Al 2 O 3 ), silica (SiO 2 ), aluminum phosphate (AlPO 4 ), glass, silicone resin, etc. The binder 18 is preferably made of an inorganic material. This is because when the binder 18 is made of an inorganic material, it does not deteriorate even when irradiated with high-energy light from a laser diode, etc.

[0047] A translucent material is one that has the property that when light in the visible light wavelength range (λ = 380 to 780 nm) is irradiated perpendicularly to a 0.5 mm target material, the radiant flux of the light that exits from the opposite side exceeds 80% of the incident light.

[0048] The phosphor layer 14 may be formed by, for example, the following manufacturing method, and is applicable to both the first embodiment described above and the second embodiment described below. One is a method of forming it as a film on the substrate 30. First, a printing paste is prepared by mixing phosphor particles 16 having a predetermined particle size with an inorganic binder, a solvent, etc., and the printing paste is applied to the substrate 30 to a predetermined thickness by a known application method such as a screen printing method or a spray method, and a film containing the phosphor particles 16 can be formed by drying and firing. The other is a method of forming it by bonding a ceramic sintered body on the substrate 30. First, phosphor particles 16 having a predetermined particle size, ceramic particles that become a light-transmitting phase, a binder, a solvent, etc. are mixed to prepare a raw material slurry, and the obtained raw material slurry is dried and granulated to prepare a granulated powder. The prepared granulated powder is press-molded and CIP-molded to prepare a molded body, and the molded body is degreased and fired to prepare a ceramic sintered body. The ceramic sintered body is bonded to the substrate 30 using an adhesive or the like. The method for producing the phosphor layer 14 is not limited to the above method.

[0049] Second embodiment A fluorescent wheel 100 according to a second embodiment of the present invention will be described with reference to FIG. 5 to FIG. 9. FIG. 5(a) and FIG. 5(b) are a plan view and a cross-sectional view, respectively, that are schematic representations of an example of the fluorescent wheel 100 according to the second embodiment. FIG. 5(b) shows a cross-section taken along line DD in FIG. 5(a). FIG. 6(a), (b), and FIG. 7(a), (b) are a plan view and a cross-sectional view, respectively, that are schematic representations of modified examples of the fluorescent wheel 100 according to the second embodiment. FIG. 6(b) shows a cross-section taken along line EE in FIG. 6(a). FIG. 7(b) shows a cross-section taken along line FF in FIG. 7(a). FIG. 8 is a plan view that is schematic representations of modified examples of the fluorescent wheel 100 according to the second embodiment. FIG. 9(a) and FIG. 9(b) are plan views that are schematic representations of modified examples of the cover 50 of the fluorescent wheel 100.

[0050] The fluorescent wheel 100 according to this embodiment includes a phosphor section 10 that is formed in an annular shape centered on the center 12 of a rotation axis, rotates about the rotation axis, and converts light of a specific range of wavelengths into light of another wavelength, and a blower section 20 that is composed of a plurality of blades 22 that rotate about the rotation axis. That is, the fluorescent wheel 100 according to this embodiment has a basic configuration similar to that of the fluorescent wheel 100 according to the first embodiment. Therefore, only the differences will be described below.

[0051] In the fluorescent wheel 100 of this embodiment, the multiple vanes 22 are each formed radially outward from the center 12 of the rotation axis, and the phosphor section 10 is formed radially outward from the multiple vanes 22 using a material different from the multiple vanes 22, and it is preferable that the phosphor section 10 and the multiple vanes 22 rotate synchronously.

[0052] In this way, by constructing the blades 22 and the phosphor section 10 from different materials, freedom is provided in the design of the shape of the blades 22. In addition, since it is possible to make each of them from different materials, freedom is also provided in the configuration of the fluorescent wheel, such as a reflective type or a transmissive type. That is, for example, it is possible to make the blades 22 from plastic that can be made into a complex shape, and to make the phosphor section 10 by forming the phosphor layer 14 on a circular ring-shaped sapphire, and the transmissive type fluorescent wheel 100 can be easily constructed. Note that constructing the blades 22 and the phosphor section 10 from different materials means that the blades 22 and the phosphor section 10 are made individually, and the materials may be the same or different.

[0053] When the phosphor section 10 is formed of the base material 30 and the phosphor layer 14, the base material 30 is formed in a circular ring shape. When the fluorescent wheel 100 is a reflective type, the base material 30 can be made of aluminum, iron, copper, or an alloy containing these. The entire base material 30 can be made of a light-reflecting material, but a light-reflecting material such as silver can be plated on one side of a material that does not take light reflection into consideration. When the fluorescent wheel 100 is a transmissive type, the base material 30 can be made of sapphire, glass, or the like. Since the temperature rises when high-energy light is irradiated, it is preferable that the thermal conductivity is high. Therefore, the base material 30 is preferably made of aluminum or sapphire.

[0054] The material of the blades 22 may be any material, such as plastic (resin), metal, or ceramics. Plastic is particularly preferable from the viewpoints of ease of molding and weight reduction. The material of the central hub that joins the multiple blades 22 may be any material, such as plastic (resin), metal, or ceramics. The material of the hub is preferably the same as the material of the multiple blades 22. The multiple blades 22 and the hub may be integrally formed by injection molding or the like, or may be formed by joining each member by welding, adhesive, or the like.

[0055] The number of the blades 22 is not particularly limited. For example, it is configured with about 3 to 10 blades. By using a small number of blades 22, the area of ​​each blade 22 can be made larger, and therefore the amount of airflow is increased. Also, the number of blades 22 is smaller, which tends to reduce wind noise, and is expected to be effective in terms of the quietness of the device. Furthermore, the number of blades 22 is smaller, which makes it possible to ensure the necessary amount of airflow even if the motor rotation speed is reduced. On the other hand, when ensuring the amount of airflow with large blades 22, it is necessary to ensure a certain amount of distance in the direction of the rotation axis of the blades 22, so it is preferable to use about 3 to 5 blades. The blades 22 are arranged at equal angles with respect to the center 12 of the rotation axis.

[0056] As shown in Fig. 5, the blades 22 and the phosphor section 10 may be directly bonded. In this case, the phosphor section 10 can be bonded to a part of the outer periphery of the blades 22 by welding or adhering with an adhesive such as epoxy resin or silicone resin. In this way, when the blades 22 and the phosphor section 10 are directly bonded to each other, it is preferable to select a metal or ceramic having excellent heat dissipation properties as the material for the blades 22. In this case, it is preferable that the thermal conductivity of the blades 22 is higher than that of the phosphor layer 14 and that the material has a thermal conductivity equal to or higher than that of the substrate 30.

[0057] 6, the blades 22 and the phosphor section 10 may not be directly joined, but a connecting member 40 may be attached to the rotating shaft to connect the connecting member 40 and the phosphor section 10. The connecting member 40 may also be made from the same material as the materials constituting the blades 22 and the base material 30. In either case of FIG. 5 or FIG. 6, the phosphor section 10 and the multiple blades 22 can rotate synchronously.

[0058] As shown in Fig. 7(a) and (b), it is preferable that the blower 20 includes two or more types of blades 22 with different outer diameters from the center 12 of the rotation axis. This makes it easier to adjust the directionality and wind power of the air blown from the fluorescent wheel 100. In addition, it is possible to generate a highly linear wind or a highly diffusive wind, etc., depending on the combination of the shapes of the blades 22. In addition, since multiple types of blades 22 are rotated on one rotation axis, this can contribute to making the light-emitting device smaller and lighter than when multiple types of blades 22 are used as multiple blower fans.

[0059] In this embodiment, two or more types of blades 22 having different outer diameters from the center 12 of the rotating shaft can be provided at different positions in the rotating shaft direction. In this case, it is preferable that the blade 22 attached to the motor side has a larger outer diameter. This makes it easy to create air flows with different properties. For example, when the outer diameter of the blade 22 having a larger outer diameter is set to 1, it is preferable to design the outer diameter of the other blade 22 to be about 0.3 to 0.6. In addition, it is preferable that each of the two or more types of blades 22 having different outer diameters from the center 12 of the rotating shaft is composed of about 3 to 5 blades.

[0060] 8, blower 20 preferably includes cover 50 that covers the front surface in the axial direction of the rotation shaft of multiple blades 22. This can prevent foreign matter from entering blades 22. Also, by making only a part of cover 50 an opening, the wind direction can be controlled.

[0061] As shown in Fig. 9(a), the cover 50 preferably includes a plurality of ribs 52 that extend in a curved shape from the center 12 of the rotation axis toward the outside in the radial direction. This makes it possible to create a constant flow of air inside the housing of the light emitting device, and makes it easier to efficiently send air even in areas away from the fluorescent wheel 100. This can provide a so-called circulator-like effect. The ribs 52 are formed of a long, thin plate-like member, and may be inclined with respect to the direction of the rotation axis.

[0062] In Fig. 8 and Fig. 9(a), the cover 50 has a plurality of ribs 52 extending linearly or curvedly from the center 12 of the rotating shaft toward the outside in the radial direction, and has an opening near the center 12 of the rotating shaft. As shown in Fig. 9(b), the cover 50 may be configured by providing an exhaust port 54 in a plate-like member. This makes it possible to control the wind direction and efficiently suppress the temperature rise inside the housing.

[0063] 5 to 8 show an example in which the phosphor section 10 is composed of a circular annular base material 30 and a phosphor layer 14 provided on one main surface 32 of the base material 30, but the phosphor section 10 of this embodiment may be composed of only the phosphor layer 14. In this case, the thickness of the phosphor layer 14 is preferably 100 μm or more and 1000 μm or less. In addition, when the fluorescent wheel 100 is a reflective type and the phosphor section 10 is composed of only the phosphor layer 14, it is preferable to provide a reflective layer made of Al, Ag, or the like on the main surface of the phosphor layer 14 opposite to the excitation light incident side. The reflective layer can be provided by sputtering, plating, or the like.

[0064] [Wheel device configuration] Fig. 10 is a schematic diagram showing an example of a wheel device 200. The wheel device 200 includes the fluorescent wheel 100 and a motor 210. The fluorescent wheel 100 is the fluorescent wheel 100 described above. The wheel device 200 in Fig. 10 shows an example in which the fluorescent wheel 100 in Fig. 1 is used.

[0065] The motor 210 rotates the phosphor section 10 and the blades 22 in synchronization with each other, and changes the position of the phosphor layer 14 of the phosphor section 10 where the excitation light is irradiated. This prevents a portion of the phosphor layer 14 from being continuously irradiated with the excitation light, thereby suppressing heat generation in the phosphor layer 14. Furthermore, by rotating the blades 22 in synchronization with the phosphor section 10, air can be blown simultaneously with one motor 210.

[0066] [Configuration of the light-emitting device] 11 is a conceptual diagram illustrating an example of a portion of a light emitting device 300. The light emitting device 300 includes a light source 310, a wheel device 200, a display device 320, and a projection optical system 330.

[0067] The light source 310 emits excitation light that excites a phosphor used in the wheel device 200. The excitation light emitted by the light source 310 is preferably blue light, violet light, or ultraviolet light. The light source 310 is preferably a laser diode.

[0068] The wheel device 200 is the above-mentioned wheel device 200. The wheel device 200 receives excitation light from the light source 310, absorbs and excites the excitation light to generate converted light with a different wavelength, and emits emitted light consisting of only the converted light or the converted light and the excitation light.

[0069] The display device 320 displays the image projected by the light emitting device 300. The display device 320 may be a liquid crystal panel, a digital mirror device (DMD), or the like.

[0070] The projection optical system 330 projects to the outside the image displayed on the display device 320 using the light emitted from the wheel device 200. The projection optical system 330 is made up of a plurality of lenses 331, and adjusts the zoom and focus.

[0071] In addition to the above configuration, the light-emitting device 300 is configured with a lens 331, a dichroic mirror 332, and the like. Also, mirrors, dichroic mirrors, lenses, prisms, and the like not shown in the figure can be used depending on the design of the light-emitting device 300. The light-emitting device 300 can omit the blower fan and the dedicated motor therefor, and can be made into a compact device by miniaturizing the light-emitting device 300. The light-emitting device 300 can be applied to projectors and the like.

[0072] As described above, the fluorescent wheel, wheel device, and light emitting device of the present invention can suppress color unevenness in the emitted fluorescent light, ensure the cooling performance of the light emitting device, and contribute to making the light emitting device smaller and lighter. [Explanation of symbols]

[0073] 10 Phosphor section 12 Center of rotation axis 14 Phosphor layer 16 Phosphor particles 18 Binding material 20 Blower section 22 Feather 30 Base material 32 Main surface 34 Opening 40 Connection member 50 Cover 52 Ribs 54 Exhaust port 100 Fluorescent Wheel 200 Wheel Device 210 Motor 300 Light emitting device 310 light source 320 Display Device 330 Projection optical system

Claims

1. 1. A fluorescent wheel, comprising: a phosphor portion that is formed in an annular shape centered on a rotation axis and rotates around the rotation axis to convert light having a wavelength in a specific range into light having another wavelength; a blower section including a plurality of blades that rotate around the rotation axis.

2. the phosphor section includes a base material formed in a disk shape and a phosphor layer formed in an annular shape on one main surface of the base material, The air blower includes an opening formed in the base material, 2. The fluorescent wheel according to claim 1, wherein the plurality of blades are provided in the opening of the base material so as to be inclined with respect to one main surface of the base material.

3. The plurality of blades are each formed radially outward from the center of the rotation shaft, The phosphor portion is formed on a radially outer side of the plurality of blades and is made of a material different from the plurality of blades, 2. The fluorescent wheel according to claim 1, wherein the phosphor portion and the plurality of blades rotate synchronously.

4. 2. The fluorescent wheel according to claim 1, wherein the blowing section includes two or more types of the blades having different outer diameters from the center of the rotation shaft.

5. 4. The fluorescent wheel according to claim 3, wherein the blowing section includes a cover that covers a front surface of the plurality of blades in an axial direction of the rotation shaft.

6. 6. The fluorescent wheel according to claim 5, wherein the cover includes a plurality of ribs extending in a curved shape from the center of the rotation shaft toward the outside in the radial direction.

7. A wheel device for use in a light emitting device, comprising: A fluorescent wheel according to any one of claims 1 to 6; A wheel device comprising: a motor for rotating the fluorescent wheel.

8. A light source that emits light in the specific range of wavelengths; The wheel device according to claim 7 , wherein the light source emits light having a wavelength in the specific range; A display device for displaying an image; a projection optical system that projects an image displayed on the display device to the outside using light emitted from the wheel device.

Images