WO2021095397A1 - Wavelength conversion element, fluorescent wheel, light source device, vehicle headlight, and projection device - Google Patents

Wavelength conversion element, fluorescent wheel, light source device, vehicle headlight, and projection device Download PDF

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Publication number
WO2021095397A1
WO2021095397A1 PCT/JP2020/037833 JP2020037833W WO2021095397A1 WO 2021095397 A1 WO2021095397 A1 WO 2021095397A1 JP 2020037833 W JP2020037833 W JP 2020037833W WO 2021095397 A1 WO2021095397 A1 WO 2021095397A1
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Prior art keywords
wavelength conversion
light source
conversion element
fluorescent
substrate
Prior art date
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PCT/JP2020/037833
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French (fr)
Japanese (ja)
Inventor
裕一 一ノ瀬
豪 鎌田
英臣 由井
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シャープ株式会社
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Publication of WO2021095397A1 publication Critical patent/WO2021095397A1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
    • F21S2/00—Systems of lighting devices, not provided for in main groups F21S4/00 - F21S10/00 or F21S19/00, e.g. of modular construction
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
    • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
    • F21S41/10—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source
    • F21S41/14—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source characterised by the type of light source
    • F21S41/16—Laser light sources
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
    • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
    • F21S41/10—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source
    • F21S41/14—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by the light source characterised by the type of light source
    • F21S41/176—Light sources where the light is generated by photoluminescent material spaced from a primary light generating element
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
    • F21S41/00—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps
    • F21S41/30—Illuminating devices specially adapted for vehicle exteriors, e.g. headlamps characterised by reflectors
    • F21S41/32—Optical layout thereof
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
    • F21V7/00—Reflectors for light sources
    • F21V7/22—Reflectors for light sources characterised by materials, surface treatments or coatings, e.g. dichroic reflectors
    • F21V7/28—Reflectors for light sources characterised by materials, surface treatments or coatings, e.g. dichroic reflectors characterised by coatings
    • F21V7/30—Reflectors for light sources characterised by materials, surface treatments or coatings, e.g. dichroic reflectors characterised by coatings the coatings comprising photoluminescent substances
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
    • F21V9/00—Elements for modifying spectral properties, polarisation or intensity of the light emitted, e.g. filters
    • F21V9/30—Elements containing photoluminescent material distinct from or spaced from the light source
    • F21V9/32—Elements containing photoluminescent material distinct from or spaced from the light source characterised by the arrangement of the photoluminescent material
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
    • F21V9/00—Elements for modifying spectral properties, polarisation or intensity of the light emitted, e.g. filters
    • F21V9/40—Elements for modifying spectral properties, polarisation or intensity of the light emitted, e.g. filters with provision for controlling spectral properties, e.g. colour, or intensity
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21W—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO USES OR APPLICATIONS OF LIGHTING DEVICES OR SYSTEMS
    • F21W2102/00—Exterior vehicle lighting devices for illuminating purposes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
    • F21Y2115/00—Light-generating elements of semiconductor light sources
    • F21Y2115/30—Semiconductor lasers

Definitions

  • the present disclosure relates to wavelength conversion elements, fluorescent wheels, light source devices, vehicle headlights, and projection devices. This disclosure claims priority based on Japanese Patent Application No. 2019-204697 filed in Japan on November 12, 2019, the contents of which are incorporated herein by reference.
  • a wavelength conversion element that irradiates a phosphor with excitation light such as a blue laser to emit light
  • excitation light such as a blue laser to emit light
  • a fluorescent guide is provided by lowering the pore density of the phosphor layer near the laser spot and increasing the pore density around the laser spot. A wavelength conversion element that suppresses is described.
  • Patent Document 2 describes a light source device that improves the reflectance and enhances the utilization efficiency of reflected light by providing a reflective portion containing titanium oxide in the lower layer of the fluorescent light emitting portion.
  • Patent Document 3 describes a light source device that attempts to utilize the fluorescence emitted from the side surface of the phosphor layer by providing a recess in the substrate and providing a reflecting member and a phosphor layer in the recess.
  • Patent Document 4 in order to improve the fluorescence efficiency and the thermal conductivity, an adhesive layer containing particles having a higher thermal conductivity than the base material and a higher light reflectance than the light reflecting layer is provided. , A fluorescent wheel in which a phosphor layer and a light reflecting layer are bonded is described.
  • JP-A-2017-111170 (published on June 22, 2017) Japanese Unexamined Patent Publication No. 2013-228598 (published on November 7, 2013) Japanese Unexamined Patent Publication No. 2015-1315455 (published on July 27, 2015)
  • FIG. 2 is a cross-sectional view schematically showing a wavelength conversion element of a related technology in which a fluorescent layer is laminated on a substrate.
  • the fluorescence generated by irradiating the fluorescent layer with the excitation light diffuses in various directions in the layer.
  • a part of the diffused fluorescence goes to the extraction side of the fluorescent layer, and is extracted from the extraction side and used.
  • the extraction side is the surface of the fluorescent layer facing the contact surface between the fluorescent layer and the substrate, and when the wavelength conversion element is a reflection type, the surface on which the excitation light is incident is intended and the wavelength conversion is performed.
  • the element is a transmissive type, it is intended to be a surface facing the surface on which the excitation light is incident.
  • the wavelength conversion element described in Patent Document 1 attempts to improve the fluorescence extraction efficiency by suppressing the light guide of fluorescence by a phosphor layer having a high pore density, but in regions having different pore densities. It is difficult to make them properly. Further, since the fluorescence guides the gaps between the pores, the effect of sufficiently improving the extraction efficiency cannot be obtained.
  • the light source device described in Patent Document 2 improves the reflectance of light toward the substrate side among the fluorescence not directed to the extraction side to improve the extraction efficiency of the fluorescence, but is on the side surface of the fluorescence layer. The heading light is still unavailable.
  • the present disclosure has been made in view of the above problems, and an object of the present disclosure is to provide a wavelength conversion element which has improved fluorescence extraction efficiency and is easy to manufacture.
  • the wavelength conversion element is arranged on a substrate having a first surface forming a planar shape and on the first surface side of the substrate, and has a plurality of fluorescences.
  • a fluorescent layer containing body particles and emitting fluorescence by excitation light, and a part of fluorescence arranged on the first surface of the substrate and having an emission angle ⁇ 1 from the fluorescent layer satisfying at least the first condition are present.
  • Three-dimensional polar coordinates that include a scattering layer that changes direction to fluorescence emitted at an extraction angle ⁇ 2 that satisfies the condition of 2, and has a negative z-axis direction in a direction perpendicular to the inside of the substrate from the first surface of the substrate.
  • the exit angle ⁇ 1 formed in the z-axis positive direction is ⁇ / 2 ⁇ ⁇ 1 ⁇
  • the take-out angle ⁇ 2 formed in the z-axis positive direction is 0 ⁇ . It is characterized in that ⁇ 2 ⁇ / 2.
  • FIG. 5 is a cross-sectional view illustrating the distance d between the end of the fluorescent layer and the end of the scattering layer and the film thickness t of the fluorescent layer in the wavelength conversion element according to the second embodiment of the present disclosure. It is a graph which shows the relationship between the ratio X of fluorescence which a direction is changed by a scattering layer, and d / t. It is sectional drawing which shows typically the wavelength conversion element which concerns on Embodiment 3 of this disclosure.
  • FIG. 1 is a cross-sectional view schematically showing the wavelength conversion element 10 according to the first embodiment of the present disclosure.
  • the wavelength conversion element 10 includes a substrate 1 having a first surface forming a planar shape, a fluorescent layer 2 arranged on the first surface side of the substrate 1, and a first surface of the substrate 1. It is provided with a scattering layer 3 arranged on the surface of the above.
  • the fluorescent layer 2 is a layer that contains a plurality of phosphor particles and emits fluorescence by excitation light.
  • the fluorescent layer 2 does not have to be in direct contact with the substrate 1, and may be arranged on the first surface side of the substrate 1, that is, on the same side as the scattering layer 3. If the fluorescent layer 2 is arranged on the first surface side of the substrate 1, another member may be provided between the fluorescent layer 2 and the substrate 1 as in the second embodiment.
  • the scattering layer 3 is a layer in which a part of the fluorescence whose emission angle ⁇ 1 from the fluorescent layer 2 satisfies at least the first condition below is changed to the fluorescence emitted at the extraction angle ⁇ 2 which satisfies the second condition below. Is.
  • the emission angle ⁇ 1 is the three-dimensional polar coordinates in which the direction perpendicular to the inside of the substrate 1 from the first surface of the substrate 1 is the negative z-axis direction, and the fluorescence emitted from the fluorescent layer 2 is in the positive z-axis direction. It is a polar angle.
  • the extraction angle ⁇ 2 is a polar angle formed by the fluorescence whose direction is changed by the scattering layer in the above three-dimensional polar coordinates in the positive direction of the z-axis.
  • the fluorescence emitted from the side surface of the fluorescence layer 2 at the emission angle ⁇ 1 that satisfies the first condition is dispersed in a direction that cannot be used.
  • the scattering layer 3 by providing the scattering layer 3, at least a part of the traveling direction of the fluorescence can be changed to the fluorescence emitted at the extraction angle ⁇ 2 satisfying the second condition.
  • the fluorescence whose direction is changed in this way can be taken out and used in the same manner as the fluorescence emitted from the fluorescence layer 2 toward the taking-out side. As a result, the efficiency of extracting fluorescence can be improved.
  • Fluorescence extraction efficiency is intended as "fluorescence intensity emitted at an extraction angle ⁇ 2 satisfying the second condition” / "excitation light intensity”, and "efficiency in which emitted fluorescence is emitted in a direction in which it can be extracted”. Is included.
  • the scattering layer 3 may be arranged so as to be in direct contact with the substrate 1 on the first surface of the substrate 1 and to be able to change the direction as described above.
  • the scattering layer 3 is formed so as to form a side wall surrounding the fluorescent layer 2 in a plan view from the positive direction of the z-axis.
  • the substrate 1 and the fluorescent layer 2 are formed. It may be arranged between and.
  • the inclination angle of the side surface of the scattering layer 3, that is, the angle ⁇ x of the polar angle formed by the side surface of the scattering layer 3 facing the side surface of the fluorescent layer 2 and the positive direction of the z-axis is not particularly limited, and 0 ⁇ ⁇ x ⁇ /. It may be any angle of 2 or ⁇ / 2 ⁇ x ⁇ .
  • the substrate 1 is a reflective substrate that reflects light, and the excitation light is incident from the first surface side of the substrate 1.
  • the reflective substrate is not particularly limited, but a metal substrate, for example, an aluminum substrate, a highly reflective alumina substrate, a white perfect scattering substrate, or the like can be used.
  • a highly reflective film such as silver may be coated on the substrate.
  • the substrate 1 is a translucent substrate that transmits light, and the excitation light is incident from the second surface side facing the first surface of the substrate 1.
  • the translucent substrate is not particularly limited, but a glass substrate or the like can be used.
  • the fluorescent layer 2 contains a first binder and phosphor particles dispersed in the first binder.
  • the first binder may be a binder containing an inorganic compound or a binder containing an organic compound.
  • the inorganic compound include alumina, silica and the like.
  • the organic compound include silicone resin and the like.
  • phosphor particles conventionally known organic phosphor particles and inorganic phosphor particles that emit fluorescence in a predetermined wavelength range by excitation light can be used.
  • the ratio of the phosphor particles to the fluorescent layer 2 is preferably about 50% by volume or more and about 75% by volume or less with respect to the fluorescent layer 2 from the viewpoint of light utilization efficiency and film thickness.
  • the volume-based median diameter (D50) of the phosphor particles is preferably about 1 ⁇ m or more and about 50 ⁇ m or less from the viewpoint of luminous efficiency and film thickness.
  • the median diameter of the particles is a numerical value measured by a laser diffraction type particle size distribution measuring device.
  • the thickness of the fluorescent layer 2 is preferably about 20 ⁇ m or more and about 120 ⁇ m or less from the viewpoint of light utilization efficiency and heat conduction.
  • the scattering layer 3 contains a second binder and scattered particles dispersed in the second binder.
  • the binder exemplified in the first binder can be used as the second binder.
  • the first binder and the second binder may be different binders or the same binder.
  • scattered particles include metal particles such as silver and metal oxide particles such as titanium oxide (TiO2) and zinc oxide (ZnO).
  • the ratio of the scattered particles to the scattering layer 3 is preferably 10% by volume or more, more preferably 50% by volume or more, and preferably 75% by volume or less with respect to the scattering layer 3. It is more preferably 70% by volume or less.
  • the volume-based median diameter (D50) of the scattered particles is preferably about 100 nm or more and about 5 ⁇ m or less from the viewpoint of the scattering effect and the film thickness.
  • the thickness of the scattering layer 3 is preferably about 20 ⁇ m or more and about 120 ⁇ m or less from the viewpoint of scattering effect and heat conduction.
  • the wavelength conversion element 10 forms the scattering layer 3 by screen-printing a mixture of the second binder and the scattered particles on the first surface of the substrate 1, and then the first binder and the phosphor particles.
  • the mixture can be produced by screen printing on the first surface side, drying and baking.
  • a dispenser may be used.
  • the inclination angle ⁇ x of the side surface of the scattering layer 3 is somewhat in the range of 0 ⁇ X ⁇ / 2 with respect to the positive z-axis direction unless otherwise controlled. It is formed at an angle. Therefore, the scattering layer 3 can be formed at a preferable inclination angle ⁇ x by a simple manufacturing method.
  • the wavelength conversion element 20 of the present embodiment is arranged in that the scattering layer 3 is arranged on the first surface of the substrate 1 and the fluorescence layer 2 is arranged on the scattering layer 3. Different from the first embodiment. Further, the wavelength conversion element 20 is a reflection type, and the excitation light is incident from the first surface side of the substrate 1.
  • the substrate 1 may be a translucent substrate or a reflective substrate. Each other configuration is the same as the configuration described in the first embodiment.
  • the wavelength conversion element 20 is formed so that the area of the scattering layer 3 on the xy plane orthogonal to the z-axis is larger than the area of the fluorescence layer 2 on the xy plane.
  • FIG. 4 shows the distance d between the end of the fluorescent layer 2 and the end of the scattering layer 3 on the xy plane orthogonal to the z-axis and the film thickness t of the fluorescent layer 2 in the wavelength conversion element 20 of the second embodiment. It is sectional drawing explaining.
  • FIG. 5 is a graph showing the relationship between X and d / t. From the viewpoint of improving the extraction efficiency, the d / t is preferably 2 or more, and more preferably 7 or more.
  • the d / t is preferably 50 or less, and more preferably 20 or less.
  • the wavelength conversion element 20 forms the scattering layer 3 by screen-printing a mixture of the second binder and the scattered particles on the first surface of the substrate 1, and then the first binder and the phosphor particles.
  • the mixture can be produced by screen printing on the scattering layer 3, drying and firing.
  • a dispenser may be used.
  • the wavelength conversion element 30 of the present embodiment is at least one of the side surfaces of the side wall formed by the scattering layer 3 facing the side surface of the fluorescent layer 2 (hereinafter, also simply referred to as “opposing surface”). It differs from the first embodiment in that the portion is in contact with at least a part of the side surface of the fluorescent layer 2.
  • Each other configuration is the same as the configuration described in the first embodiment.
  • the second binder constituting the scattering layer 3 has a higher thermal conductivity than air. Therefore, since the wavelength conversion element 30 of the present embodiment can dissipate the heat generated in the fluorescent layer 2 to the scattering layer 3, it is possible to further suppress the decrease in brightness due to temperature quenching as compared with the first embodiment.
  • the second binder may be a binder containing an organic compound, but from the viewpoint of heat dissipation, a binder containing an inorganic compound is preferable.
  • the interface where the side surface of the fluorescent layer 2 and the facing surface of the side wall formed by the scattering layer 3 are in contact with each other may be inclined at an arbitrary angle with respect to the positive direction of the z-axis.
  • FIG. 6 shows a configuration in which the cross section of the side wall formed by the scattering layer 3 on the plane parallel to the z-axis has a divergent shape in the negative direction of the z-axis.
  • the cross section on the plane parallel to the z-axis may have a divergent shape in the negative direction of the z-axis.
  • the interface between the side surface of the fluorescent layer 2 and the facing surface of the scattering layer 3 does not have to be inclined with respect to the positive direction of the z-axis.
  • the scattering layer 3a is arranged on the first surface of the substrate 1, the fluorescent layer 2 is arranged on the scattering layer 3a, and further, scattering is performed.
  • the layer 3b differs from the first embodiment and the second embodiment in that the layer 3b is arranged so as to form a side wall surrounding the fluorescent layer 2.
  • the wavelength conversion element 40 is a reflection type, and the excitation light is incident from the first surface side of the substrate 1.
  • the substrate 1 may be a translucent substrate or a reflective substrate. Each other configuration is the same as the configuration described in the first and second embodiments.
  • the inner side surface of the side wall formed by the scattering layer 3b and the side surface of the fluorescent layer 2 are not in contact with each other, but as shown in FIG. 10, these surfaces are in contact with each other. There may be.
  • the vehicle headlights include the wavelength conversion elements 10, 20, 30, and 40 according to the first to fourth embodiments, the light source that irradiates the wavelength conversion elements 10, 20, 30, and 40 with excitation light, and the wavelength conversion element 10.
  • a reflector having a reflecting surface that reflects the fluorescence emitted from 20, 30, and 40 is provided, and the reflecting surface of the reflector has a shape that reflects the incident light so as to be emitted in parallel in a certain direction.
  • the light source is preferably a blue laser light source that emits excitation light having a wavelength that excites the fluorescence layer 2 of the wavelength conversion elements 10, 20, 30, and 40.
  • the reflector is preferably composed of a semi-parabolic mirror. It is preferable that the paraboloid is divided into two vertically in parallel with the xy plane to form a semi-paraboloid, and the inner surface thereof is a mirror.
  • the reflector has a through hole through which the excitation light passes.
  • the wavelength conversion elements 10, 20, 30, and 40 are excited by blue excitation light and fluoresce emit light in the long wavelength region (yellow wavelength) of visible light.
  • the excitation light also hits the wavelength conversion elements 10, 20, 30, and 40 and becomes diffusely reflected light.
  • the wavelength conversion elements 10, 20, 30, and 40 are arranged at the focal positions of the paraboloid.
  • the wavelength conversion elements 10, 20, 30, and 40 are at the focal positions of the parabolic mirror, the fluorescence emission and diffuse reflection light emitted from the wavelength conversion elements 10, 20, 30, and 40 hit the reflector. When reflected, it goes straight to the exit surface uniformly.
  • White light which is a mixture of fluorescent light and diffusely reflected light, is emitted from the exit surface as parallel light.
  • the substrate 1 of the wavelength conversion elements 10, 20, 30, and 40 of the first to fourth embodiments is a wheel.
  • at least one of the wavelength conversion elements 10, 20, 30, and 40 is arranged in at least a part in the circumferential direction of the surface of the wheel through which the excitation light emitted from the light source passes.
  • At least one of the wavelength conversion elements 10, 20, 30, and 40 may be arranged in at least a part in the circumferential direction of the surface of the wheel through which the excitation light emitted from the light source passes, and the wavelength conversion is performed.
  • the elements 10, 20, 30, and 40 are preferably arranged concentrically on the wheel.
  • FIGS. 11 to 14 show a plan view (xy plane) of the fluorescent wheel.
  • the fluorescent layer 148 is deposited around the surface of the wheel 141.
  • the fluorescent wheel is divided into a plurality of segments in the circumferential direction, and the phosphor is applied to each segment, so that the external quantum yield can be maintained at a high level. This makes it possible to create various colors while maintaining brightness.
  • FIG. 11 is a plan view showing a mode in which the fluorescent wheel is divided into a plurality of segments and a plurality of different fluorescent layers 148 are deposited for each segment in at least a part in the circumferential direction through which the excitation light passes.
  • the fluorescent layer 148a fluoresces at a wavelength corresponding to red
  • the fluorescent layer 148b fluoresces at a wavelength corresponding to green when irradiated with excitation light.
  • the fluorescent wheel usually preferably reflects the excitation light, but a part of the segment can be a transmitting portion 143 through which the excitation light is transmitted.
  • the transmissive portion 143 is preferably made of glass. With such a segment configuration, the excitation light can be converted into a plurality of wavelengths by one fluorescent wheel.
  • FIGS. 12-14 show another preferred embodiment.
  • FIG. 12 shows a configuration in which the segment designated as the transmission portion 143 in FIG. 11 is the reflection portion.
  • FIG. 13 shows a configuration in which the segment as the reflection portion of FIG. 12 is the transmission portion 143.
  • FIG. 14 shows a fluorescent wheel with yet another segment. It is preferable that the fluorescent layer 148c is deposited on yet another segment. It is preferable that the fluorescent layer 148c fluoresces at a wavelength corresponding to yellow by irradiation with excitation light.
  • the fluorescent layers 148, 148a, 148b, and 148c the fluorescent layers 2 of the wavelength conversion elements 10, 20, 30, and 40 of the first to fourth embodiments can be adopted.
  • the light source device includes the fluorescence wheel according to the sixth embodiment, a driving device for rotating the fluorescence wheel, and a light source for irradiating the wavelength conversion elements 10, 20, 30, and 40 with excitation light.
  • the light source device emits fluorescence when excitation light is incident on the fluorescence layers 2 of the wavelength conversion elements 10, 20, 30, and 40 arranged at least in the circumferential direction of the surface of the fluorescence wheel as the fluorescence wheel rotates. ..
  • the light source device is preferably used for a projector or the like.
  • the light source is preferably a blue laser light source that emits excitation light having a wavelength that excites the fluorescence layer 2 of the wavelength conversion elements 10, 20, 30, and 40.
  • FIG. 15 shows a side view showing the configuration of the light source device 101.
  • the fluorescent wheel is fixed to the rotating shaft 147 of the drive device 142 by a fixture 146.
  • the drive device 142 is preferably a motor, and a fluorescent wheel fixed to a rotating shaft 147, which is a rotating shaft of the motor, with a fixture 146 rotates with the rotation of the motor.
  • the fluorescent layer 148 deposited on the peripheral portion on the surface of the wheel 141 receives the excitation light and emits fluorescent light. Since the fluorescent layer 148 rotates with the rotation of the fluorescent wheel, the fluorescent layer 148 emits fluorescent light while rotating at any time. As the fluorescent wheel, the fluorescent wheel of the fifth embodiment can be adopted.
  • FIG. 16 shows a schematic view showing the configuration of the projection device 100 using the light source device 101 according to the seventh embodiment.
  • the projection device 100 includes a light source device 101, a rotation position sensor 103 that acquires the rotation position of the fluorescent wheel, a light source control unit 104 that controls the light source 13 based on output information from the rotation position sensor 103, and a display element 107.
  • the light source side optical system 106 that guides the light from the light source device to the display element 107, and the projection side optical system 108 that projects the projected light from the display element 107 onto the screen are provided.
  • the projection device 100 controls the output of the light source 13 based on the information on the rotation position of the fluorescent wheel acquired by the rotation position sensor 103.
  • the light source device includes a fluorescence wheel in which a wavelength conversion element is divided into a plurality of segments in the circumferential direction and arranged in at least a part of the circumferential direction through which the excitation light 14 emitted from the light source 13 passes. It may be an undivided fluorescent wheel.
  • the excitation light 14 of blue light emission passes through the fluorescent wheel via the transmitting portion 143.
  • the excitation light 14 that irradiates the fluorescent layer 148 can pass through the light source side optical system 106 and the mirrors 109a to 109c on the optical path.
  • the light source side optical system 106 is preferably a dichroic mirror.
  • a preferred dichroic mirror can reflect blue light incident at 45 degrees and transmit red and green light.
  • the blue light from the excitation light 14 incident on the dichroic mirror is reflected and directed to the fluorescent wheel.
  • blue light is transmitted through the fluorescent wheel through the transmission portion 143.
  • the excitation light 14 irradiated to the segment other than the transmission portion 143 due to the rotation timing of the fluorescent wheel emits fluorescence by irradiating the fluorescent layer 148.
  • the fluorescence layer 148a emits fluorescence in the red wavelength band
  • the fluorescence layer 148b emits fluorescence in the green wavelength band.
  • the fluorescently emitted red and green lights pass through the dichroic mirror and enter the display element 107.
  • the blue light transmitted through the transmission unit 143 is incident on the dichroic mirror again through the mirrors 109a to 109c, is reflected again by the dichroic mirror, and is incident on the display element 107.
  • the projector can include the light source device 101, a display element 107, a light source side optical system 106 (dichroic mirror), and a projection side optical system 108.
  • the light source side optical system 106 (dichroic mirror) guides the light from the light source device 101 to the display element 107, and the projection side optical system 108 projects the projected light from the display element 107 onto a screen or the like. it can.
  • the display element 107 is preferably a DMD (Digital Mirror Device).
  • the projection side optical system 108 preferably consists of a combination of projection lens.
  • the wavelength conversion elements (10, 20, 30, 40) according to the first aspect of the present disclosure are on a substrate (1) having a first surface forming a planar shape and on the first surface side of the substrate (1).
  • a fluorescent layer (2, 148, 148a, 148b, 148c) that is arranged and contains a plurality of phosphor particles and emits fluorescence by excitation light (14) and is arranged on the first surface of the substrate (1).
  • a part of the fluorescence whose emission angle ⁇ 1 from the fluorescent layer (2, 148, 148a, 148b, 148c) satisfies at least the first condition is changed to the fluorescence emitted at the extraction angle ⁇ 2 which satisfies the second condition.
  • the first The condition is that the emission angle ⁇ 1 formed in the positive direction of the z-axis is ⁇ / 2 ⁇ ⁇ 1 ⁇ , and the second condition is that the extraction angle ⁇ 2 formed in the positive direction of the z-axis is 0 ⁇ ⁇ 2 ⁇ / 2.
  • the scattering layer (3, 3a) is arranged on the first surface of the substrate (1), and the fluorescent layer. (2, 148, 148a, 148b, 148c) is arranged on the scattering layer (3, 3a), and the area of the scattering layer (3, 3a) in the xy plane orthogonal to the z axis is the area of the scattering layer (3, 3a) in the xy plane.
  • the configuration may be larger than the area of the fluorescent layer (2, 148, 148a, 148b, 148c).
  • the wavelength conversion element (10, 30, 40) is the scattering layer (3, 3b) arranged on the first surface of the substrate (1) in the above aspect 1 or 2. Is a configuration that constitutes a side wall surrounding the fluorescent layer (2, 148, 148a, 148b, 148c) arranged on the first surface side of the substrate (1) in a plan view from the z-axis positive direction. May be good.
  • the wavelength conversion element (30, 40) has at least a part of the inner side surface of the side wall formed by the scattering layer (3, 3b). It may be configured to be in contact with at least a part of the side surface of the fluorescent layer (2, 148, 148a, 148b, 148c).
  • the fluorescent wheel according to the fifth aspect of the present disclosure is a fluorescent wheel in which the substrate (1) of the wavelength conversion element (10, 20, 30, 40) according to any one of the above aspects 1 to 4 is a wheel (141).
  • the wavelength conversion elements (10, 20, 30, 40) are arranged at least in the circumferential direction of the surface of the wheel through which the excitation light (14) emitted from the light source (13) passes. It is a configuration that has.
  • the light source device (101) includes the fluorescent wheel according to the fifth aspect, a driving device (142) for rotating the fluorescent wheel, and the wavelength conversion element (10, 20, 30, 40).
  • a light source (13) that irradiates excitation light (14)
  • the wavelength conversion elements (10, 20, 30) are arranged at least in the circumferential direction of the surface of the fluorescent wheel as the fluorescent wheel rotates. , 40), when the excitation light (14) is incident on the fluorescent layer (2, 148, 148a, 148b, 148c), the fluorescence is emitted.
  • the vehicle headlights according to the seventh aspect of the present disclosure include the wavelength conversion element (10, 20, 30, 40) according to any one of the above aspects 1 to 4, and the wavelength conversion element (10, 20, 30).
  • , 40) is provided with a light source for irradiating excitation light and a reflector having a reflecting surface for reflecting fluorescence emitted from the wavelength conversion elements (10, 20, 30, 40), and the reflecting surface of the reflector is incident. It has a shape that reflects the emitted light so as to be emitted in parallel in a certain direction.
  • the projection device (100) according to the eighth aspect of the present disclosure is the light source device (101), the display element (107), and the light from the light source device (101) according to the sixth aspect. ), And a projection side optical system (108) that projects the projected light from the display element (107) onto the screen.
  • the projection device (100) according to the ninth aspect of the present disclosure is described in any one of the above aspects 1 to 4 in at least a part of the circumferential direction through which the excitation light (14) emitted from the light source (13) passes.
  • the light source side optical system (106) that guides the light from the display element (107) to the display element (107), and the projection side optical system (108) that projects the projected light from the display element (107) onto the screen.
  • the output of the light source (13) is controlled by the information on the rotation position of the fluorescent wheel acquired by the rotation position sensor (103).

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Abstract

Provided is a wavelength conversion element with which fluorescent light extraction efficiency can be improved and which can be manufactured easily. The wavelength conversion element is characterized by comprising: a substrate that constitutes a planar shape; a fluorescent layer that is disposed on a first surface side of the substrate; and a scattering layer that is disposed on the first surface of the substrate, and that directionally changes a portion of fluorescent light which has an emission angle θ1 from the fluorescent layer of π/2≦θ1<π to fluorescent light which is emitted at an extraction angle θ2 satisfying 0≦θ2<π/2.

Description

波長変換素子、蛍光ホイール、光源装置、車両用前照灯具及び投影装置Wavelength converters, fluorescent wheels, light source devices, vehicle headlights and projection devices
　本開示は、波長変換素子、蛍光ホイール、光源装置、車両用前照灯具及び投影装置に関する。本開示は、２０１９年１１月１２日に、日本に出願された特願２０１９－２０４６９７号に基づく優先権を主張するものであり、その内容をここに援用する。 The present disclosure relates to wavelength conversion elements, fluorescent wheels, light source devices, vehicle headlights, and projection devices. This disclosure claims priority based on Japanese Patent Application No. 2019-204697 filed in Japan on November 12, 2019, the contents of which are incorporated herein by reference.
　青色レーザ等の励起光を蛍光体に照射し発光させる波長変換素子において、基板上に積層した蛍光層に励起光を照射し、発生した蛍光を取り出して利用することが従来技術として知られている。 In a wavelength conversion element that irradiates a phosphor with excitation light such as a blue laser to emit light, it is known as a prior art to irradiate the fluorescence layer laminated on a substrate with excitation light and extract and use the generated fluorescence. ..
　例えば、特許文献１には、蛍光材料および複数の気孔を有する蛍光体層において、レーザスポット付近の蛍光体層の気孔密度を低く、その周辺の気孔密度を高くすることにより、蛍光の導光を抑制する波長変換素子が記載されている。 For example, in Patent Document 1, in a fluorescent material and a phosphor layer having a plurality of pores, a fluorescent guide is provided by lowering the pore density of the phosphor layer near the laser spot and increasing the pore density around the laser spot. A wavelength conversion element that suppresses is described.
　特許文献２には、蛍光発光部の下層に、酸化チタンを含む反射部を設けることにより、反射率を向上させて反射光の利用効率を高める光源装置が記載されている。 Patent Document 2 describes a light source device that improves the reflectance and enhances the utilization efficiency of reflected light by providing a reflective portion containing titanium oxide in the lower layer of the fluorescent light emitting portion.
　特許文献３には、基板に凹部を設け、当該凹部に反射部材および蛍光体層を設けることにより、蛍光体層の側面から射出した蛍光の利用を試みる光源装置が記載されている。 Patent Document 3 describes a light source device that attempts to utilize the fluorescence emitted from the side surface of the phosphor layer by providing a recess in the substrate and providing a reflecting member and a phosphor layer in the recess.
　特許文献４には、蛍光効率および熱伝導率を向上させるために、基材よりも熱伝導率が高く、且つ、光反射層よりも光の反射率が高い粒子を含有する接着層を介して、蛍光体層と光反射層とを接着した蛍光ホイールが記載されている。 In Patent Document 4, in order to improve the fluorescence efficiency and the thermal conductivity, an adhesive layer containing particles having a higher thermal conductivity than the base material and a higher light reflectance than the light reflecting layer is provided. , A fluorescent wheel in which a phosphor layer and a light reflecting layer are bonded is described.
特開２０１７－１１１１７０号公報（２０１７年６月２２日公開）JP-A-2017-111170 (published on June 22, 2017) 特開２０１３－２２８５９８号公報（２０１３年１１月７日公開）Japanese Unexamined Patent Publication No. 2013-228598 (published on November 7, 2013) 特開２０１５－１３１５４５５号公報（２０１５年７月２７日公開）Japanese Unexamined Patent Publication No. 2015-1315455 (published on July 27, 2015)
　図２は、基板上に蛍光層を積層した関連技術の波長変換素子を模式的に示した断面図である。 FIG. 2 is a cross-sectional view schematically showing a wavelength conversion element of a related technology in which a fluorescent layer is laminated on a substrate.
　図２に示されるように、関連技術の波長変換素子において、励起光の蛍光層への照射により発生した蛍光は、層内で種々の方向に拡散する。拡散した蛍光の一部は、蛍光層の取り出し側に向かい、そこから取り出されて利用される。その一方で、層内で拡散した蛍光の一部は蛍光層の側面に向かい、そこから漏出する結果、取り出して利用することができないという問題がある。なお、取り出し側とは、蛍光層の、蛍光層と基板との接触面に対向する面であって、波長変換素子が反射型である場合は、励起光が入射した面を意図し、波長
変換素子が透過型である場合は、励起光が入射した面の対向面を意図する。 As shown in FIG. 2, in the wavelength conversion element of the related technology, the fluorescence generated by irradiating the fluorescent layer with the excitation light diffuses in various directions in the layer. A part of the diffused fluorescence goes to the extraction side of the fluorescent layer, and is extracted from the extraction side and used. On the other hand, there is a problem that a part of the fluorescence diffused in the layer goes to the side surface of the fluorescent layer and leaks from the side surface, and as a result, cannot be taken out and used. The extraction side is the surface of the fluorescent layer facing the contact surface between the fluorescent layer and the substrate, and when the wavelength conversion element is a reflection type, the surface on which the excitation light is incident is intended and the wavelength conversion is performed. When the element is a transmissive type, it is intended to be a surface facing the surface on which the excitation light is incident.
　これに対し、特許文献１に記載される波長変換素子は、気孔密度の高い蛍光体層により蛍光の導光を抑制し、蛍光の取り出し効率の向上を試みるものであるが、気孔密度の異なる領域の作り分けが困難である。また、気孔の隙間を蛍光が導光するため、取出し効率の十分な向上効果が得られない。 On the other hand, the wavelength conversion element described in Patent Document 1 attempts to improve the fluorescence extraction efficiency by suppressing the light guide of fluorescence by a phosphor layer having a high pore density, but in regions having different pore densities. It is difficult to make them properly. Further, since the fluorescence guides the gaps between the pores, the effect of sufficiently improving the extraction efficiency cannot be obtained.
　特許文献２に記載される光源装置は、取り出し側に向かわない蛍光のうち、基板側へ向かう光の反射率を向上させて、蛍光の取り出し効率を向上させるものであるが、蛍光層の側面に向かう光は、依然として利用することができない。 The light source device described in Patent Document 2 improves the reflectance of light toward the substrate side among the fluorescence not directed to the extraction side to improve the extraction efficiency of the fluorescence, but is on the side surface of the fluorescence layer. The heading light is still unavailable.
　特許文献３に記載される光源装置は、基板に凹部を設ける加工が困難である。 In the light source device described in Patent Document 3, it is difficult to process a recess in the substrate.
　本開示は、上記の問題に鑑みて為されたものであり、その目的は、蛍光の取り出し効率が向上され、且つ、製造が容易である波長変換素子を提供することにある。 The present disclosure has been made in view of the above problems, and an object of the present disclosure is to provide a wavelength conversion element which has improved fluorescence extraction efficiency and is easy to manufacture.
　上記の課題を解決するために、本開示の一態様に係る波長変換素子は、平面形状を構成する第１の面を有する基板と、前記基板の第１の面側に配置され、複数の蛍光体粒子を含み、励起光により蛍光を発する蛍光層と、前記基板の第１の面上に配置され、前記蛍光層からの出射角度θ１が少なくとも第１の条件を満たす蛍光の一部を、第２の条件を満たす取出角度θ２にて出射する蛍光に方向転換させる散乱層と、を備え、前記基板の第１の面から垂直に当該基板内部に向かう方向をｚ軸負方向とする３次元極座標において、前記第１の条件は、ｚ軸正方向となす出射角度θ１が、π／２≦θ１＜πであり、前記第２の条件は、ｚ軸正方向となす取出角度θ２が、０≦θ２＜π／２であることを特徴とする。 In order to solve the above problems, the wavelength conversion element according to one aspect of the present disclosure is arranged on a substrate having a first surface forming a planar shape and on the first surface side of the substrate, and has a plurality of fluorescences. A fluorescent layer containing body particles and emitting fluorescence by excitation light, and a part of fluorescence arranged on the first surface of the substrate and having an emission angle θ1 from the fluorescent layer satisfying at least the first condition are present. Three-dimensional polar coordinates that include a scattering layer that changes direction to fluorescence emitted at an extraction angle θ2 that satisfies the condition of 2, and has a negative z-axis direction in a direction perpendicular to the inside of the substrate from the first surface of the substrate. In the first condition, the exit angle θ1 formed in the z-axis positive direction is π / 2 ≦ θ1 <π, and in the second condition, the take-out angle θ2 formed in the z-axis positive direction is 0 ≦. It is characterized in that θ2 <π / 2.
　本開示の一態様によれば、蛍光の取り出し効率が向上され、且つ、製造が容易である波長変換素子を提供することができる。 According to one aspect of the present disclosure, it is possible to provide a wavelength conversion element in which fluorescence extraction efficiency is improved and manufacturing is easy.
本開示の実施形態１に係る波長変換素子を模式的に示した断面図である。It is sectional drawing which shows typically the wavelength conversion element which concerns on Embodiment 1 of this disclosure. 関連技術の波長変換素子を模式的に示した断面図である。It is sectional drawing which shows typically the wavelength conversion element of the related technology. 本開示の実施形態２に係る波長変換素子を模式的に示した断面図である。It is sectional drawing which shows typically the wavelength conversion element which concerns on Embodiment 2 of this disclosure. 本開示の実施形態２に係る波長変換素子において、蛍光層の端部と散乱層の端部との距離ｄ、および、蛍光層の膜厚ｔを説明する断面図である。FIG. 5 is a cross-sectional view illustrating the distance d between the end of the fluorescent layer and the end of the scattering layer and the film thickness t of the fluorescent layer in the wavelength conversion element according to the second embodiment of the present disclosure. 散乱層により方向転換される蛍光の割合Ｘとｄ／ｔとの関係を示すグラフである。It is a graph which shows the relationship between the ratio X of fluorescence which a direction is changed by a scattering layer, and d / t. 本開示の実施形態３に係る波長変換素子を模式的に示した断面図である。It is sectional drawing which shows typically the wavelength conversion element which concerns on Embodiment 3 of this disclosure. 本開示の実施形態３に係る波長変換素子の変形例を模式的に示した断面図である。It is sectional drawing which shows typically the modification of the wavelength conversion element which concerns on Embodiment 3 of this disclosure. 本開示の実施形態３に係る波長変換素子の変形例を模式的に示した断面図である。It is sectional drawing which shows typically the modification of the wavelength conversion element which concerns on Embodiment 3 of this disclosure. 本開示の実施形態４に係る波長変換素子を模式的に示した断面図である。It is sectional drawing which shows typically the wavelength conversion element which concerns on Embodiment 4 of this disclosure. 本開示の実施形態４に係る波長変換素子の変形例を模式的に示した断面図である。It is sectional drawing which shows typically the modification of the wavelength conversion element which concerns on Embodiment 4 of this disclosure. 本開示の実施形態６に係る蛍光ホイールの構成を示す平面図である。It is a top view which shows the structure of the fluorescent wheel which concerns on Embodiment 6 of this disclosure. 本開示の実施形態６に係る蛍光ホイールの変形例の構成を示す平面図である。It is a top view which shows the structure of the modification of the fluorescent wheel which concerns on Embodiment 6 of this disclosure. 本開示の実施形態６に係る蛍光ホイールの変形例の構成を示す平面図である。It is a top view which shows the structure of the modification of the fluorescent wheel which concerns on Embodiment 6 of this disclosure. 本開示の実施形態６に係る蛍光ホイールの変形例の構成を示す平面図である。It is a top view which shows the structure of the modification of the fluorescent wheel which concerns on Embodiment 6 of this disclosure. 本開示の実施形態７に係る光源装置の構成を示す側面図である。It is a side view which shows the structure of the light source apparatus which concerns on Embodiment 7 of this disclosure. 本開示の実施形態８に係る投影装置の構成を示す概略図である。It is the schematic which shows the structure of the projection apparatus which concerns on Embodiment 8 of this disclosure.
　〔実施形態１〕
　以下、本開示の一実施形態について、詳細に説明する。 [Embodiment 1]
Hereinafter, one embodiment of the present disclosure will be described in detail.
　図１は、本開示の実施形態１に係る波長変換素子１０を模式的に示した断面図である。図１に示すように、波長変換素子１０は、平面形状を構成する第１の面を有する基板１と、基板１の第１の面側に配置される蛍光層２と、基板１の第１の面上に配置される散乱層３とを備える。 FIG. 1 is a cross-sectional view schematically showing the wavelength conversion element 10 according to the first embodiment of the present disclosure. As shown in FIG. 1, the wavelength conversion element 10 includes a substrate 1 having a first surface forming a planar shape, a fluorescent layer 2 arranged on the first surface side of the substrate 1, and a first surface of the substrate 1. It is provided with a scattering layer 3 arranged on the surface of the above.
　蛍光層２は、複数の蛍光体粒子を含み、励起光により蛍光を発する層である。蛍光層２は、直接基板１に接していなくてもよく、基板１の第１の面側、すなわち、散乱層３と同じ側に配置されていればよい。蛍光層２が、基板１の第１の面側に配置されていれば、実施形態２のように、蛍光層２と基板１との間に他の部材を備えていてもよい。 The fluorescent layer 2 is a layer that contains a plurality of phosphor particles and emits fluorescence by excitation light. The fluorescent layer 2 does not have to be in direct contact with the substrate 1, and may be arranged on the first surface side of the substrate 1, that is, on the same side as the scattering layer 3. If the fluorescent layer 2 is arranged on the first surface side of the substrate 1, another member may be provided between the fluorescent layer 2 and the substrate 1 as in the second embodiment.
　散乱層３は、蛍光層２からの出射角度θ１が少なくとも以下の第１の条件を満たす蛍光の一部を、以下の第２の条件を満たす取出角度θ２にて出射する蛍光に方向転換させる層である。 The scattering layer 3 is a layer in which a part of the fluorescence whose emission angle θ1 from the fluorescent layer 2 satisfies at least the first condition below is changed to the fluorescence emitted at the extraction angle θ2 which satisfies the second condition below. Is.
　第１の条件：π／２≦θ１＜π
　第２の条件：０≦θ２＜π／２
　ここで、出射角度θ１は、基板１の第１の面から垂直に当該基板１内部に向かう方向をｚ軸負方向とする３次元極座標において、蛍光層２から出射する蛍光が、ｚ軸正方向となす極角である。また、取出角度θ２は、上記３次元極座標において、散乱層により方向転換された蛍光が、ｚ軸正方向となす極角である。 First condition: π / 2 ≤ θ1 <π
Second condition: 0 ≤ θ2 <π / 2
Here, the emission angle θ1 is the three-dimensional polar coordinates in which the direction perpendicular to the inside of the substrate 1 from the first surface of the substrate 1 is the negative z-axis direction, and the fluorescence emitted from the fluorescent layer 2 is in the positive z-axis direction. It is a polar angle. Further, the extraction angle θ2 is a polar angle formed by the fluorescence whose direction is changed by the scattering layer in the above three-dimensional polar coordinates in the positive direction of the z-axis.
　散乱層３を有しない関連技術の波長変換素子においては、蛍光層２の側面から第１の条件を満たす出射角度θ１で出射する蛍光は、利用することができない方向へと離散してしまう。 In the wavelength conversion element of the related technology that does not have the scattering layer 3, the fluorescence emitted from the side surface of the fluorescence layer 2 at the emission angle θ1 that satisfies the first condition is dispersed in a direction that cannot be used.
　これに対し、散乱層３を設けることにより、当該蛍光の少なくとも一部の進行方向を、第２の条件を満たす取出角度θ２にて出射する蛍光に方向転換させることができる。このように方向転換された蛍光は、蛍光層２から取り出し側に向かって出射する蛍光と同様に、取り出して利用することができる。その結果、蛍光の取り出し効率を高めることができる。 On the other hand, by providing the scattering layer 3, at least a part of the traveling direction of the fluorescence can be changed to the fluorescence emitted at the extraction angle θ2 satisfying the second condition. The fluorescence whose direction is changed in this way can be taken out and used in the same manner as the fluorescence emitted from the fluorescence layer 2 toward the taking-out side. As a result, the efficiency of extracting fluorescence can be improved.
　「蛍光の取り出し効率」とは、「第２の条件を満たす取出角度θ２にて出射する蛍光強度」／「励起光強度」を意図し、「発光した蛍光が、取り出し可能な方向に出射する効率」が含まれる。 "Fluorescence extraction efficiency" is intended as "fluorescence intensity emitted at an extraction angle θ2 satisfying the second condition" / "excitation light intensity", and "efficiency in which emitted fluorescence is emitted in a direction in which it can be extracted". Is included.
　散乱層３は、基板１の第１の面上に直接基板１と接するように、且つ、上述の方向転換が可能なように配置されていればよい。本実施形態において、散乱層３は、上記ｚ軸正方向からの平面視において、蛍光層２を囲う側壁を構成するように形成されるが、実施形態２のように、基板１と蛍光層２との間に配置されていてもよい。 The scattering layer 3 may be arranged so as to be in direct contact with the substrate 1 on the first surface of the substrate 1 and to be able to change the direction as described above. In the present embodiment, the scattering layer 3 is formed so as to form a side wall surrounding the fluorescent layer 2 in a plan view from the positive direction of the z-axis. However, as in the second embodiment, the substrate 1 and the fluorescent layer 2 are formed. It may be arranged between and.
　散乱層３の側面の傾斜角度、すなわち、蛍光層２の側面と対向する散乱層３の側面とｚ軸正方向とがなす極角の角度θｘは、特に限定されず、０≦θｘ＜π／２またはπ／２＜θｘ＜πの任意の角度であってよい。 The inclination angle of the side surface of the scattering layer 3, that is, the angle θx of the polar angle formed by the side surface of the scattering layer 3 facing the side surface of the fluorescent layer 2 and the positive direction of the z-axis is not particularly limited, and 0 ≦ θx <π /. It may be any angle of 2 or π / 2 <θx <π.
　（基板１）
　波長変換素子１０が反射型である場合、基板１は、光を反射する反射性基板であり、励起光は、基板１の第１の面側から入射する。反射性基板としては、特に限定されないが、金属基板、例えば、アルミ基板、高反射のアルミナ基板、白色完全散乱基板等を用いることができる。基板上に銀等の高反射膜がコーティングされていてもよい。 (Board 1)
When the wavelength conversion element 10 is a reflective type, the substrate 1 is a reflective substrate that reflects light, and the excitation light is incident from the first surface side of the substrate 1. The reflective substrate is not particularly limited, but a metal substrate, for example, an aluminum substrate, a highly reflective alumina substrate, a white perfect scattering substrate, or the like can be used. A highly reflective film such as silver may be coated on the substrate.
　波長変換素子１０が透過型である場合、基板１は、光を透過する透光性基板であり、励起光は、基板１の第１の面に対向する第２の面側から入射する。透光性基板としては、特に限定されないが、ガラス基板等を用いることができる。 When the wavelength conversion element 10 is a transmissive type, the substrate 1 is a translucent substrate that transmits light, and the excitation light is incident from the second surface side facing the first surface of the substrate 1. The translucent substrate is not particularly limited, but a glass substrate or the like can be used.
　（蛍光層２）
　蛍光層２は、第１のバインダと、第１のバインダ内に分散した蛍光体粒子とを含んでいる。 (Fluorescent layer 2)
The fluorescent layer 2 contains a first binder and phosphor particles dispersed in the first binder.
　第１のバインダは、無機化合物を含むバインダであってもよく、有機化合物を含むバインダであってもよい。無機化合物としては、例えば、アルミナ、シリカ等が挙げられる。有機化合物としては、例えば、シリコーン樹脂等が挙げられる。 The first binder may be a binder containing an inorganic compound or a binder containing an organic compound. Examples of the inorganic compound include alumina, silica and the like. Examples of the organic compound include silicone resin and the like.
　蛍光体粒子は、励起光により所定の波長域の蛍光を発する従来公知の有機蛍光体粒子および無機蛍光体粒子を用いることができる。 As the phosphor particles, conventionally known organic phosphor particles and inorganic phosphor particles that emit fluorescence in a predetermined wavelength range by excitation light can be used.
　蛍光層２に占める蛍光体粒子の割合は、光利用効率および膜厚の観点から、蛍光層２に対して５０体積％以上、且つ、７５体積％以下程度であるのが好ましい。 The ratio of the phosphor particles to the fluorescent layer 2 is preferably about 50% by volume or more and about 75% by volume or less with respect to the fluorescent layer 2 from the viewpoint of light utilization efficiency and film thickness.
　蛍光体粒子の体積基準のメジアン径（Ｄ５０）は、発光効率および膜厚の観点から、１μｍ以上、且つ、５０μｍ以下程度であるのが好ましい。なお、本願明細書において、粒子のメジアン径は、レーザー回折式粒度分布測定装置によって測定される数値である。 The volume-based median diameter (D50) of the phosphor particles is preferably about 1 μm or more and about 50 μm or less from the viewpoint of luminous efficiency and film thickness. In the specification of the present application, the median diameter of the particles is a numerical value measured by a laser diffraction type particle size distribution measuring device.
　蛍光層２の厚さは、光利用効率および熱伝導の観点から、２０μｍ以上、且つ、１２０μｍ以下程度であるのが好ましい。 The thickness of the fluorescent layer 2 is preferably about 20 μm or more and about 120 μm or less from the viewpoint of light utilization efficiency and heat conduction.
　（散乱層３）
　散乱層３は、第２のバインダと、第２のバインダ内に分散した散乱粒子と、を含んでいる。 (Scattering layer 3)
The scattering layer 3 contains a second binder and scattered particles dispersed in the second binder.
　第２のバインダは、第１のバインダで例示したバインダを用いることができる。第１のバインダと第２のバインダとは、異なるバインダであっても、同一のバインダであってもよい。 As the second binder, the binder exemplified in the first binder can be used. The first binder and the second binder may be different binders or the same binder.
　散乱粒子は、銀等の金属粒子、および、酸化チタン（ＴｉＯ２）、酸化亜鉛（ＺｎＯ）等の金属酸化物粒子等が挙げられる。 Examples of the scattered particles include metal particles such as silver and metal oxide particles such as titanium oxide (TiO2) and zinc oxide (ZnO).
　散乱層３に占める散乱粒子の割合は、散乱層３に対して１０体積％以上であることが好ましく、５０体積％以上であることがより好ましく、また、７５体積％以下であることが好ましく、７０体積％以下であるのがより好ましい。当該構成であることにより、基板１への密着性を有しつつ、上述した効果を奏することができる。 The ratio of the scattered particles to the scattering layer 3 is preferably 10% by volume or more, more preferably 50% by volume or more, and preferably 75% by volume or less with respect to the scattering layer 3. It is more preferably 70% by volume or less. With this configuration, the above-mentioned effects can be obtained while maintaining adhesion to the substrate 1.
　散乱粒子の体積基準のメジアン径（Ｄ５０）は、散乱効果および膜厚の観点から、１００ｎｍ以上、且つ、５μｍ以下程度であるのが好ましい。 The volume-based median diameter (D50) of the scattered particles is preferably about 100 nm or more and about 5 μm or less from the viewpoint of the scattering effect and the film thickness.
　散乱層３の厚さは、散乱効果および熱伝導の観点から、２０μｍ以上、且つ、１２０μｍ以下程度であるのが好ましい。 The thickness of the scattering layer 3 is preferably about 20 μm or more and about 120 μm or less from the viewpoint of scattering effect and heat conduction.
　（製造方法）
　波長変換素子１０は、第２のバインダと散乱粒子との混合物を、基板１の第１の面上にスクリーン印刷することにより散乱層３を形成し、次いで、第１のバインダと蛍光体粒子との混合物を、第１の面側にスクリーン印刷し、乾燥および焼成することにより、製造することができる。あるいは、第１のバインダおよび第２のバインダが有機化合物を含むバインダである場合は、ディスペンサを用いてもよい。 (Production method)
The wavelength conversion element 10 forms the scattering layer 3 by screen-printing a mixture of the second binder and the scattered particles on the first surface of the substrate 1, and then the first binder and the phosphor particles. The mixture can be produced by screen printing on the first surface side, drying and baking. Alternatively, if the first binder and the second binder are binders containing an organic compound, a dispenser may be used.
　スクリーン印刷またはディスペンサを用いて散乱層３を形成すると、散乱層３の側面の傾斜角度θｘは、特に制御を行わない限り、０＜θＸ＜π／２の範囲でｚ軸正方向に対していくらか傾斜して形成される。したがって、簡便な製造方法により、好ましい傾斜角度θｘで、散乱層３を形成することができる。 When the scattering layer 3 is formed by screen printing or a dispenser, the inclination angle θx of the side surface of the scattering layer 3 is somewhat in the range of 0 <θX <π / 2 with respect to the positive z-axis direction unless otherwise controlled. It is formed at an angle. Therefore, the scattering layer 3 can be formed at a preferable inclination angle θx by a simple manufacturing method.
　〔実施形態２〕
　本開示の他の実施形態について、以下に説明する。なお、説明の便宜上、上記実施形態にて説明した部材と同じ機能を有する部材については、同じ符号を付記し、その説明を繰り返さない。 [Embodiment 2]
Other embodiments of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be added to the members having the same functions as the members described in the above embodiment, and the description will not be repeated.
　（波長変換素子２０の構成）
　図３に示されるように、本実施形態の波長変換素子２０は、散乱層３が基板１の第１の面上に配置され、蛍光層２が散乱層３上に配置されている点において、実施形態１と異なる。また、波長変換素子２０は反射型であり、励起光は、基板１の第１の面側から入射する。基板１は、透光性基板であっても、反射性基板であってもよい。その他の各構成は、実施形態１において説明した構成と同じである。 (Structure of wavelength conversion element 20)
As shown in FIG. 3, the wavelength conversion element 20 of the present embodiment is arranged in that the scattering layer 3 is arranged on the first surface of the substrate 1 and the fluorescence layer 2 is arranged on the scattering layer 3. Different from the first embodiment. Further, the wavelength conversion element 20 is a reflection type, and the excitation light is incident from the first surface side of the substrate 1. The substrate 1 may be a translucent substrate or a reflective substrate. Each other configuration is the same as the configuration described in the first embodiment.
　波長変換素子２０は、ｚ軸と直交するｘｙ平面における散乱層３の面積が、ｘｙ平面における蛍光層２の面積よりも大きくなるように形成される。散乱層３をこのように形成することにより、反射性基板では反射によって利用することができない方向へと射出していた蛍光、すなわち、蛍光層２の側面から上記第１の条件を満たす出射角度θ１にて出射する蛍光の一部を、第２の条件を満たす取出角度θ２にて出射する蛍光に方向転換させることができる。 The wavelength conversion element 20 is formed so that the area of the scattering layer 3 on the xy plane orthogonal to the z-axis is larger than the area of the fluorescence layer 2 on the xy plane. By forming the scattering layer 3 in this way, the fluorescence emitted in a direction that cannot be used by reflection on the reflective substrate, that is, the emission angle θ1 satisfying the first condition from the side surface of the fluorescence layer 2. It is possible to change the direction of a part of the fluorescence emitted in the above to the fluorescence emitted at the extraction angle θ2 satisfying the second condition.
　図４は、本実施形態２の波長変換素子２０において、ｚ軸と直交するｘｙ平面における蛍光層２の端部と散乱層３の端部との距離ｄ、および、蛍光層２の膜厚ｔを説明する断面図である。 FIG. 4 shows the distance d between the end of the fluorescent layer 2 and the end of the scattering layer 3 on the xy plane orthogonal to the z-axis and the film thickness t of the fluorescent layer 2 in the wavelength conversion element 20 of the second embodiment. It is sectional drawing explaining.
　蛍光層２の側面から第１の条件を満たす出射角度θ１にて出射する蛍光のうち、散乱層３により方向転換される蛍光の割合Ｘは、上記ｄとｔとの比ｄ／ｔに相関し、下記式（１）により近似される。
Ｘ〔％〕＝｛ａｔａｎ（ｄ／ｔ）／９０｝×１００　　（１）
　図５は、Ｘとｄ／ｔとの関係を示すグラフである。取り出し効率の向上の観点から、上記ｄ／ｔは２以上であることが好ましく、７以上であることがより好ましい。また、蛍光層２の発光量を確保する観点から、ｄ／ｔは５０以下であることが好ましく、２０以下であることがより好ましい。なお、ｄ／ｔ＝２であるとき、Ｘは７０．５％程度となり、ｄ／ｔ＝７であるとき、Ｘは９１％程度となる。また、ｄ／ｔ＝２０であるとき、Ｘは９６．８％程度となり、ｄ／ｔ＝５０であるとき、Ｘは９８．７％程度となる。 Of the fluorescence emitted from the side surface of the fluorescent layer 2 at the emission angle θ1 satisfying the first condition, the ratio X of the fluorescence whose direction is changed by the scattering layer 3 correlates with the ratio d / t of the above d and t. , It is approximated by the following equation (1).
X [%] = {atan (d / t) / 90} × 100 (1)
FIG. 5 is a graph showing the relationship between X and d / t. From the viewpoint of improving the extraction efficiency, the d / t is preferably 2 or more, and more preferably 7 or more. Further, from the viewpoint of ensuring the amount of light emitted from the fluorescent layer 2, the d / t is preferably 50 or less, and more preferably 20 or less. When d / t = 2, X is about 70.5%, and when d / t = 7, X is about 91%. Further, when d / t = 20, X is about 96.8%, and when d / t = 50, X is about 98.7%.
　波長変換素子２０は、第２のバインダと散乱粒子との混合物を、基板１の第１の面上にスクリーン印刷することにより散乱層３を形成し、次いで、第１のバインダと蛍光体粒子との混合物を、散乱層３上にスクリーン印刷し、乾燥および焼成することにより、製造することができる。あるいは、第１のバインダおよび第２のバインダが有機化合物を含むバインダである場合は、ディスペンサを用いてもよい。 The wavelength conversion element 20 forms the scattering layer 3 by screen-printing a mixture of the second binder and the scattered particles on the first surface of the substrate 1, and then the first binder and the phosphor particles. The mixture can be produced by screen printing on the scattering layer 3, drying and firing. Alternatively, if the first binder and the second binder are binders containing an organic compound, a dispenser may be used.
　〔実施形態３〕
　本開示の他の実施形態について、以下に説明する。なお、説明の便宜上、上記実施形態にて説明した部材と同じ機能を有する部材については、同じ符号を付記し、その説明を繰り返さない。 [Embodiment 3]
Other embodiments of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be added to the members having the same functions as the members described in the above embodiment, and the description will not be repeated.
　（波長変換素子３０の構成）
　図６に示されるように、本実施形態の波長変換素子３０は、散乱層３が構成する側壁の、蛍光層２の側面と対向する面（以下、単に「対向面」ともいう）の少なくとも一部が、蛍光層２の側面の少なくとも一部と接している点において、実施形態１と異なる。その他の各構成は、実施形態１において説明した構成と同じである。 (Structure of wavelength conversion element 30)
As shown in FIG. 6, the wavelength conversion element 30 of the present embodiment is at least one of the side surfaces of the side wall formed by the scattering layer 3 facing the side surface of the fluorescent layer 2 (hereinafter, also simply referred to as “opposing surface”). It differs from the first embodiment in that the portion is in contact with at least a part of the side surface of the fluorescent layer 2. Each other configuration is the same as the configuration described in the first embodiment.
　励起光が蛍光体へ入射する際に、蛍光体が局所的に高温になることにより温度消光が生じることが知られている。つまり、青色レーザ等により蛍光体を発光させた場合、高出力照射時に所望の蛍光発光強度を得ることができないという問題がある。 It is known that when the excitation light is incident on the phosphor, the phosphor becomes locally hot, causing temperature quenching. That is, when a phosphor is made to emit light by a blue laser or the like, there is a problem that a desired fluorescence emission intensity cannot be obtained at the time of high-power irradiation.
　この問題に対し、散乱層３を構成する第２のバインダは、空気よりも熱伝導率が高い。したがって、本実施形態の波長変換素子３０は、蛍光層２で発生した熱を散乱層３に放熱し得るため、実施形態１よりも、温度消光による輝度低下をより抑制することができる。 For this problem, the second binder constituting the scattering layer 3 has a higher thermal conductivity than air. Therefore, since the wavelength conversion element 30 of the present embodiment can dissipate the heat generated in the fluorescent layer 2 to the scattering layer 3, it is possible to further suppress the decrease in brightness due to temperature quenching as compared with the first embodiment.
　本実施形態において、第２のバインダは、有機化合物を含むバインダであってもよいが、放熱性の観点からは、無機化合物を含むバインダであることが好ましい。 In the present embodiment, the second binder may be a binder containing an organic compound, but from the viewpoint of heat dissipation, a binder containing an inorganic compound is preferable.
　蛍光層２の側面と散乱層３が構成する側壁の上記対向面とが接している界面は、ｚ軸正方向に対して、任意の角度で傾斜していてよい。図６では、散乱層３が構成する側壁のｚ軸と平行な面における断面が、ｚ軸負方向に向かって末広がり形状となる構成を示したが、図７に示されるように、蛍光層２のｚ軸と平行な面における断面が、ｚ軸負方向に向かって末広がり形状となる構成であってもよい。また、図８に示されるように、蛍光層２の側面と散乱層３の上記対向面との界面が、ｚ軸正方向に対して傾斜していなくてもよい。 The interface where the side surface of the fluorescent layer 2 and the facing surface of the side wall formed by the scattering layer 3 are in contact with each other may be inclined at an arbitrary angle with respect to the positive direction of the z-axis. FIG. 6 shows a configuration in which the cross section of the side wall formed by the scattering layer 3 on the plane parallel to the z-axis has a divergent shape in the negative direction of the z-axis. The cross section on the plane parallel to the z-axis may have a divergent shape in the negative direction of the z-axis. Further, as shown in FIG. 8, the interface between the side surface of the fluorescent layer 2 and the facing surface of the scattering layer 3 does not have to be inclined with respect to the positive direction of the z-axis.
　〔実施形態４〕
　本開示の他の実施形態について、以下に説明する。なお、説明の便宜上、上記実施形態にて説明した部材と同じ機能を有する部材については、同じ符号を付記し、その説明を繰り返さない。 [Embodiment 4]
Other embodiments of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be added to the members having the same functions as the members described in the above embodiment, and the description will not be repeated.
　（波長変換素子４０の構成）
　図９に示されるように、本実施形態の波長変換素子４０は、散乱層３ａが、基板１の第１の面上に配置され、蛍光層２が散乱層３ａ上に配置され、さらに、散乱層３ｂが、蛍光層２を囲う側壁を構成するように配置されている点において、実施形態１および実施形態２と異なる。また、波長変換素子４０は反射型であり、励起光は、基板１の第１の面側から入射する。基板１は、透光性基板であっても、反射性基板であってもよい。その他の各構成は、実施形態１および実施形態２において説明した構成と同じである。 (Structure of wavelength conversion element 40)
As shown in FIG. 9, in the wavelength conversion element 40 of the present embodiment, the scattering layer 3a is arranged on the first surface of the substrate 1, the fluorescent layer 2 is arranged on the scattering layer 3a, and further, scattering is performed. The layer 3b differs from the first embodiment and the second embodiment in that the layer 3b is arranged so as to form a side wall surrounding the fluorescent layer 2. Further, the wavelength conversion element 40 is a reflection type, and the excitation light is incident from the first surface side of the substrate 1. The substrate 1 may be a translucent substrate or a reflective substrate. Each other configuration is the same as the configuration described in the first and second embodiments.
　散乱層３ａおよび散乱層３ｂを設けることにより、何れか一方の散乱層のみを設ける場合よりも、蛍光の取り出し効率を一層高めることができる。 By providing the scattering layer 3a and the scattering layer 3b, it is possible to further improve the fluorescence extraction efficiency as compared with the case where only one of the scattering layers is provided.
　図９では、散乱層３ｂが構成する側壁の内側面と、蛍光層２の側面とは接していない構成を示したが、図１０に示されるように、これらの面が互いに接している構成であってもよい。 In FIG. 9, the inner side surface of the side wall formed by the scattering layer 3b and the side surface of the fluorescent layer 2 are not in contact with each other, but as shown in FIG. 10, these surfaces are in contact with each other. There may be.
　〔実施形態５〕
　本開示の他の実施形態について、以下に説明する。なお、説明の便宜上、上記実施形態にて説明した部材と同じ機能を有する部材については、同じ符号を付記し、その説明を繰り返さない。 [Embodiment 5]
Other embodiments of the present disclosure will be described below. For convenience of explanation, the same reference numerals will be added to the members having the same functions as the members described in the above embodiment, and the description will not be repeated.
　（車両用前照灯具の構成）
　車両用前照灯具は、実施形態１～４に係る波長変換素子１０、２０、３０、４０と、波長変換素子１０、２０、３０、４０に励起光を照射する光源と、波長変換素子１０、２０、３０、４０から出射した蛍光を反射させる反射面を有するリフレクタと、を備えており、リフレクタの反射面は、入射した光を一定方向に平行に出射するように反射させる形状を有する。 (Composition of headlights for vehicles)
The vehicle headlights include the wavelength conversion elements 10, 20, 30, and 40 according to the first to fourth embodiments, the light source that irradiates the wavelength conversion elements 10, 20, 30, and 40 with excitation light, and the wavelength conversion element 10. A reflector having a reflecting surface that reflects the fluorescence emitted from 20, 30, and 40 is provided, and the reflecting surface of the reflector has a shape that reflects the incident light so as to be emitted in parallel in a certain direction.
　光源は、波長変換素子１０、２０、３０、４０の蛍光層２を励起する波長の励起光を出射する青色レーザ光源であるのが好ましい。 The light source is preferably a blue laser light source that emits excitation light having a wavelength that excites the fluorescence layer 2 of the wavelength conversion elements 10, 20, 30, and 40.
　リフレクタは、半放物面ミラーから構成されるのが好ましい。放物面をｘｙ平面に平行に上下に２分割して半放物面とし、その内面はミラーになっているのが好ましい。リフレクタには励起光が通過する透孔がある。波長変換素子１０、２０、３０、４０は、青色の励起光によって励起され、可視光の長波長域（黄色波長）の光を蛍光発光する。また、励起光は、波長変換素子１０、２０、３０、４０に当たって拡散反射光ともなる。波長変換素子１０、２０、３０、４０は、放物面の焦点の位置に配置される。波長変換素子１０、２０、３０、４０が、放物面ミラーの焦点の位置にあるので、波長変換素子１０、２０、３０、４０から出射された蛍光発光、拡散反射光は、リフレクタへ当たって反射すると、一様に出射面に直進する。蛍光発光と拡散反射光とが混ざり合った白色光が平行光として出射面から出射する。 The reflector is preferably composed of a semi-parabolic mirror. It is preferable that the paraboloid is divided into two vertically in parallel with the xy plane to form a semi-paraboloid, and the inner surface thereof is a mirror. The reflector has a through hole through which the excitation light passes. The wavelength conversion elements 10, 20, 30, and 40 are excited by blue excitation light and fluoresce emit light in the long wavelength region (yellow wavelength) of visible light. The excitation light also hits the wavelength conversion elements 10, 20, 30, and 40 and becomes diffusely reflected light. The wavelength conversion elements 10, 20, 30, and 40 are arranged at the focal positions of the paraboloid. Since the wavelength conversion elements 10, 20, 30, and 40 are at the focal positions of the parabolic mirror, the fluorescence emission and diffuse reflection light emitted from the wavelength conversion elements 10, 20, 30, and 40 hit the reflector. When reflected, it goes straight to the exit surface uniformly. White light, which is a mixture of fluorescent light and diffusely reflected light, is emitted from the exit surface as parallel light.
　〔実施形態６〕
　本発明の他の実施形態について、以下に説明する。なお、説明の便宜上、上記実施形態にて説明した部材と同じ機能を有する部材については、同じ符号を付記し、その説明を繰り返さない。 [Embodiment 6]
Other embodiments of the present invention will be described below. For convenience of explanation, the same reference numerals will be added to the members having the same functions as the members described in the above embodiment, and the description will not be repeated.
　（蛍光ホイールの構成）
　本実施形態の蛍光ホイールは、実施形態１～４の波長変換素子１０、２０、３０、４０の基板１が、ホイールである。蛍光ホイールは、光源から出射された励起光が通過するホイールの表面の周方向の少なくとも一部に、少なくとも何れかの波長変換素子１０、２０、３０、４０が配置されている。 (Configuration of fluorescent wheel)
In the fluorescent wheel of the present embodiment, the substrate 1 of the wavelength conversion elements 10, 20, 30, and 40 of the first to fourth embodiments is a wheel. In the fluorescent wheel, at least one of the wavelength conversion elements 10, 20, 30, and 40 is arranged in at least a part in the circumferential direction of the surface of the wheel through which the excitation light emitted from the light source passes.
　蛍光ホイールは、光源から出射された励起光が通過するホイールの表面の周方向の少なくとも一部に、少なくとも何れかの波長変換素子１０、２０、３０、４０が配置されていればよく、波長変換素子１０、２０、３０、４０は、同心円状にホイール上に配置されていることが好ましい。 In the fluorescent wheel, at least one of the wavelength conversion elements 10, 20, 30, and 40 may be arranged in at least a part in the circumferential direction of the surface of the wheel through which the excitation light emitted from the light source passes, and the wavelength conversion is performed. The elements 10, 20, 30, and 40 are preferably arranged concentrically on the wheel.
　図１１～１４に、蛍光ホイールの平面図（ｘｙ平面）を示す。好ましい実施形態では、ホイール１４１の表面上の周辺部に蛍光層１４８が堆積される。 FIGS. 11 to 14 show a plan view (xy plane) of the fluorescent wheel. In a preferred embodiment, the fluorescent layer 148 is deposited around the surface of the wheel 141.
　蛍光体の外部量子収率が低い状態で励起すると、励起光に対して蛍光発光が弱くなり色味のバランスが悪くなるという課題がある。これを避けるために励起光をフィルターで減衰させたり、時分割で出力を低下させるといった調整があるが、明るさの低減となり好ましくない。係る問題を解消すべく、蛍光ホイールを周方向に複数のセグメントに分割し、蛍光体をセグメント毎に塗り分けることにより、外部量子収率を高い水準に維持することが可能となる。これにより、明るさを維持しつつ様々な色を作り出すことができる。 When excited with a low external quantum yield of the phosphor, there is a problem that the fluorescence emission becomes weak with respect to the excitation light and the color balance becomes poor. In order to avoid this, there are adjustments such as attenuating the excitation light with a filter or reducing the output by time division, but this is not preferable because it reduces the brightness. In order to solve this problem, the fluorescent wheel is divided into a plurality of segments in the circumferential direction, and the phosphor is applied to each segment, so that the external quantum yield can be maintained at a high level. This makes it possible to create various colors while maintaining brightness.
　図１１は、蛍光ホイールを複数のセグメントに分割し、励起光が通過する周方向の少なくとも一部に複数の異なる蛍光層１４８をセグメント毎に堆積した態様を示す平面図である。好ましい実施形態では、励起光の照射により蛍光層１４８ａは、赤色に相当する波長を蛍光発光し、蛍光層１４８ｂは、緑色に相当する波長を蛍光発光するのが好ましい。蛍光ホイールは通常は励起光を反射するのが好ましいが、セグメントの一部を励起光が透過する透過部１４３とすることができる。好ましい実施形態では、透過部１４３はガラスからなることが好ましい。係るセグメント構成とすることにより、励起光を１つの蛍光ホイールで複数の波長に変換させることが可能となる。 FIG. 11 is a plan view showing a mode in which the fluorescent wheel is divided into a plurality of segments and a plurality of different fluorescent layers 148 are deposited for each segment in at least a part in the circumferential direction through which the excitation light passes. In a preferred embodiment, it is preferable that the fluorescent layer 148a fluoresces at a wavelength corresponding to red and the fluorescent layer 148b fluoresces at a wavelength corresponding to green when irradiated with excitation light. The fluorescent wheel usually preferably reflects the excitation light, but a part of the segment can be a transmitting portion 143 through which the excitation light is transmitted. In a preferred embodiment, the transmissive portion 143 is preferably made of glass. With such a segment configuration, the excitation light can be converted into a plurality of wavelengths by one fluorescent wheel.
　図１２～１４に別の好ましい実施形態を示す。図１２は、図１１にて透過部１４３としたセグメントを反射部とする構成を示す。図１３は、図１２の反射部としたセグメントを透過部１４３とする構成を示す。図１４は、更に別のセグメントを設けた蛍光ホイールを示す。更に別のセグメントには蛍光層１４８ｃが堆積されるのが好ましい。励起光の照射により蛍光層１４８ｃは、黄色に相当する波長を蛍光発光するのが好ましい。 FIGS. 12-14 show another preferred embodiment. FIG. 12 shows a configuration in which the segment designated as the transmission portion 143 in FIG. 11 is the reflection portion. FIG. 13 shows a configuration in which the segment as the reflection portion of FIG. 12 is the transmission portion 143. FIG. 14 shows a fluorescent wheel with yet another segment. It is preferable that the fluorescent layer 148c is deposited on yet another segment. It is preferable that the fluorescent layer 148c fluoresces at a wavelength corresponding to yellow by irradiation with excitation light.
　蛍光層１４８、１４８ａ、１４８ｂ、１４８ｃは、実施形態１～４の波長変換素子１０、２０、３０、４０の蛍光層２を採用することができる。 As the fluorescent layers 148, 148a, 148b, and 148c, the fluorescent layers 2 of the wavelength conversion elements 10, 20, 30, and 40 of the first to fourth embodiments can be adopted.
　〔実施形態７〕
　本発明の他の実施形態について、以下に説明する。なお、説明の便宜上、上記実施形態にて説明した部材と同じ機能を有する部材については、同じ符号を付記し、その説明を繰り返さない。 [Embodiment 7]
Other embodiments of the present invention will be described below. For convenience of explanation, the same reference numerals will be added to the members having the same functions as the members described in the above embodiment, and the description will not be repeated.
　（光源装置の構成）
　光源装置は、実施形態６に係る蛍光ホイールと、蛍光ホイールを回転させる駆動装置と、波長変換素子１０、２０、３０、４０に励起光を照射する光源とを備えている。 (Configuration of light source device)
The light source device includes the fluorescence wheel according to the sixth embodiment, a driving device for rotating the fluorescence wheel, and a light source for irradiating the wavelength conversion elements 10, 20, 30, and 40 with excitation light.
　光源装置は、蛍光ホイールの回転に伴い、少なくとも蛍光ホイールの表面の周方向に配置された波長変換素子１０、２０、３０、４０の蛍光層２に励起光が入射した際に、蛍光を出射する。 The light source device emits fluorescence when excitation light is incident on the fluorescence layers 2 of the wavelength conversion elements 10, 20, 30, and 40 arranged at least in the circumferential direction of the surface of the fluorescence wheel as the fluorescence wheel rotates. ..
　光源装置は、好ましくはプロジェクタ等に用いられる。光源装置では、光源は、波長変換素子１０、２０、３０、４０の蛍光層２を励起する波長の励起光を出射する青色レーザ光源であるのが好ましい。 The light source device is preferably used for a projector or the like. In the light source device, the light source is preferably a blue laser light source that emits excitation light having a wavelength that excites the fluorescence layer 2 of the wavelength conversion elements 10, 20, 30, and 40.
　図１５に、光源装置１０１の構成を示す側面図を示す。好ましい実施形態では、蛍光ホイールは固定具１４６で、駆動装置１４２の回転軸１４７に固定される。駆動装置１４２は好ましくはモータであり、モータの回転シャフトである回転軸１４７に固定具１４６で固定された蛍光ホイールがモータの回転に伴い回転する。 FIG. 15 shows a side view showing the configuration of the light source device 101. In a preferred embodiment, the fluorescent wheel is fixed to the rotating shaft 147 of the drive device 142 by a fixture 146. The drive device 142 is preferably a motor, and a fluorescent wheel fixed to a rotating shaft 147, which is a rotating shaft of the motor, with a fixture 146 rotates with the rotation of the motor.
　ホイール１４１の表面上の周辺部に堆積された蛍光層１４８が、励起光を受けて蛍光発光を出射する。蛍光層１４８は、蛍光ホイールの回転に伴い回転するため随時回転しながら、蛍光発光を出射する。蛍光ホイールとしては、実施形態５の蛍光ホイールを採用することができる。 The fluorescent layer 148 deposited on the peripheral portion on the surface of the wheel 141 receives the excitation light and emits fluorescent light. Since the fluorescent layer 148 rotates with the rotation of the fluorescent wheel, the fluorescent layer 148 emits fluorescent light while rotating at any time. As the fluorescent wheel, the fluorescent wheel of the fifth embodiment can be adopted.
　〔実施形態８〕
　本発明の他の実施形態について、以下に説明する。なお、説明の便宜上、上記実施形態にて説明した部材と同じ機能を有する部材については、同じ符号を付記し、その説明を繰り返さない。 [Embodiment 8]
Other embodiments of the present invention will be described below. For convenience of explanation, the same reference numerals will be added to the members having the same functions as the members described in the above embodiment, and the description will not be repeated.
　（投影装置の構成）
　図１６に、実施形態７に係る光源装置１０１を利用した投影装置１００の構成を示す概略図を示す。 (Configuration of projection device)
FIG. 16 shows a schematic view showing the configuration of the projection device 100 using the light source device 101 according to the seventh embodiment.
　投影装置１００は、光源装置１０１と、蛍光ホイールの回転位置を取得する回転位置センサ１０３と、回転位置センサ１０３からの出力情報に基づいて光源１３を制御する光源制御部１０４と、表示素子１０７と、光源装置からの光を表示素子１０７まで導光する光源側光学系１０６と、表示素子１０７からの投影光をスクリーンに投影する投影側光学系１０８とを備えている。 The projection device 100 includes a light source device 101, a rotation position sensor 103 that acquires the rotation position of the fluorescent wheel, a light source control unit 104 that controls the light source 13 based on output information from the rotation position sensor 103, and a display element 107. The light source side optical system 106 that guides the light from the light source device to the display element 107, and the projection side optical system 108 that projects the projected light from the display element 107 onto the screen are provided.
　投影装置１００は、回転位置センサ１０３により取得された蛍光ホイールの回転位置の情報により光源１３の出力を制御する。光源装置は、光源１３から出射された励起光１４が通過する周方向の少なくとも一部に、波長変換素子が周方向に複数セグメントに分割されて配置された蛍光ホイールを備えているが、セグメントに分割されていない蛍光ホイールであってもよい。 The projection device 100 controls the output of the light source 13 based on the information on the rotation position of the fluorescent wheel acquired by the rotation position sensor 103. The light source device includes a fluorescence wheel in which a wavelength conversion element is divided into a plurality of segments in the circumferential direction and arranged in at least a part of the circumferential direction through which the excitation light 14 emitted from the light source 13 passes. It may be an undivided fluorescent wheel.
　蛍光ホイールのセグメントの一部に透過部１４３を設けた場合（図１３参照）、青色発光の励起光１４は透過部１４３を介して蛍光ホイールを透過する。蛍光層１４８を照射する励起光１４は、光路上にて光源側光学系１０６、ミラー１０９ａ～１０９ｃを通ることができる。光源側光学系１０６はダイクロイックミラーであるのが好ましい。好ましいダイクロイックミラーは、４５度で入射した青色の光は反射させ、赤色および緑色の光は透過させることができる。 When the transmitting portion 143 is provided in a part of the segment of the fluorescent wheel (see FIG. 13), the excitation light 14 of blue light emission passes through the fluorescent wheel via the transmitting portion 143. The excitation light 14 that irradiates the fluorescent layer 148 can pass through the light source side optical system 106 and the mirrors 109a to 109c on the optical path. The light source side optical system 106 is preferably a dichroic mirror. A preferred dichroic mirror can reflect blue light incident at 45 degrees and transmit red and green light.
　より詳細に検討すると、上記光学特性を備えたダイクロイックミラーを光源側光学系１０６に採用することにより、ダイクロイックミラーに入射する励起光１４による青色の光は反射されて蛍光ホイールに向けられる。蛍光ホイールの回転のタイミングにより、青色の光は透過部１４３を介して蛍光ホイールを透過する。蛍光ホイールの回転のタイミングにより、透過部１４３以外のセグメントに照射された励起光１４は、蛍光層１４８を照射することにより蛍光発光する。セグメント毎に蛍光層１４８ａでは赤色波長帯域の蛍光が発光され、蛍光層１４８ｂでは緑色波長帯域の蛍光が発光される。蛍光発光された赤色および緑色の光は、ダイクロイックミラーを透過して表示素子１０７に入射する。透過部１４３を透過した青色の光は、ミラー１０９ａ～１０９ｃを介して再度ダイクロイックミラーに入射し、ダイクロイックミラーで再度反射されて表示素子１０７に入射する。 Examining in more detail, by adopting a dichroic mirror having the above optical characteristics for the light source side optical system 106, the blue light from the excitation light 14 incident on the dichroic mirror is reflected and directed to the fluorescent wheel. Depending on the timing of rotation of the fluorescent wheel, blue light is transmitted through the fluorescent wheel through the transmission portion 143. The excitation light 14 irradiated to the segment other than the transmission portion 143 due to the rotation timing of the fluorescent wheel emits fluorescence by irradiating the fluorescent layer 148. For each segment, the fluorescence layer 148a emits fluorescence in the red wavelength band, and the fluorescence layer 148b emits fluorescence in the green wavelength band. The fluorescently emitted red and green lights pass through the dichroic mirror and enter the display element 107. The blue light transmitted through the transmission unit 143 is incident on the dichroic mirror again through the mirrors 109a to 109c, is reflected again by the dichroic mirror, and is incident on the display element 107.
　好ましい実施形態では、プロジェクタ（投影装置１００）は、上記光源装置１０１と、表示素子１０７と、光源側光学系１０６（ダイクロイックミラー）と、投影側光学系１０８と、を備えることができる。光源側光学系１０６（ダイクロイックミラー）は、光源装置１０１からの光を上記表示素子１０７まで導光し、投影側光学系１０８は、上記表示素子１０７からの投影光をスクリーン等に投影することができる。好ましい実施形態では、表示素子１０７はＤＭＤ（デジタルミラーデバイス）であるのが好ましい。投影側光学系１０８は投影部レンズの組み合わせからなるのが好ましい。 In a preferred embodiment, the projector (projection device 100) can include the light source device 101, a display element 107, a light source side optical system 106 (dichroic mirror), and a projection side optical system 108. The light source side optical system 106 (dichroic mirror) guides the light from the light source device 101 to the display element 107, and the projection side optical system 108 projects the projected light from the display element 107 onto a screen or the like. it can. In a preferred embodiment, the display element 107 is preferably a DMD (Digital Mirror Device). The projection side optical system 108 preferably consists of a combination of projection lens.
　〔まとめ〕
　本開示の態様１に係る波長変換素子（１０、２０、３０、４０）は、平面形状を構成する第１の面を有する基板（１）と、前記基板（１）の第１の面側に配置され、複数の蛍光体粒子を含み、励起光（１４）により蛍光を発する蛍光層（２、１４８、１４８ａ、１４８ｂ、１４８ｃ）と、前記基板（１）の第１の面上に配置され、前記蛍光層（２、１４８、１４８ａ、１４８ｂ、１４８ｃ）からの出射角度θ１が少なくとも第１の条件を満たす蛍光の一部を、第２の条件を満たす取出角度θ２にて出射する蛍光に方向転換させる散乱層（３、３ａ、３ｂ）と、を備え、前記基板（１）の第１の面から垂直に当該基板内部に向かう方向をｚ軸負方向とする３次元極座標において、前記第１の条件は、ｚ軸正方向となす出射角度θ１が、π／２≦θ１＜πであり、前記第２の条件は、ｚ軸正方向となす取出角度θ２が、０≦θ２＜π／２である構成である。 [Summary]
The wavelength conversion elements (10, 20, 30, 40) according to the first aspect of the present disclosure are on a substrate (1) having a first surface forming a planar shape and on the first surface side of the substrate (1). A fluorescent layer (2, 148, 148a, 148b, 148c) that is arranged and contains a plurality of phosphor particles and emits fluorescence by excitation light (14) and is arranged on the first surface of the substrate (1). A part of the fluorescence whose emission angle θ1 from the fluorescent layer (2, 148, 148a, 148b, 148c) satisfies at least the first condition is changed to the fluorescence emitted at the extraction angle θ2 which satisfies the second condition. In three-dimensional polar coordinates in which a scattering layer (3, 3a, 3b) is provided, and the direction perpendicular to the inside of the substrate from the first surface of the substrate (1) is the negative z-axis direction, the first The condition is that the emission angle θ1 formed in the positive direction of the z-axis is π / 2 ≦ θ1 <π, and the second condition is that the extraction angle θ2 formed in the positive direction of the z-axis is 0 ≦ θ2 <π / 2. There is a certain configuration.
　本開示の態様２に係る波長変換素子（２０、４０）は、上記の態様１において、前記散乱層（３、３ａ）が前記基板（１）の第１の面上に配置され、前記蛍光層（２、１４８、１４８ａ、１４８ｂ、１４８ｃ）が前記散乱層（３、３ａ）上に配置され、前記ｚ軸と直交するｘｙ平面における前記散乱層（３、３ａ）の面積が、前記ｘｙ平面における前記蛍光層（２、１４８、１４８ａ、１４８ｂ、１４８ｃ）の面積よりも大きい構成としてもよい。 In the wavelength conversion element (20, 40) according to the second aspect of the present disclosure, in the above aspect 1, the scattering layer (3, 3a) is arranged on the first surface of the substrate (1), and the fluorescent layer. (2, 148, 148a, 148b, 148c) is arranged on the scattering layer (3, 3a), and the area of the scattering layer (3, 3a) in the xy plane orthogonal to the z axis is the area of the scattering layer (3, 3a) in the xy plane. The configuration may be larger than the area of the fluorescent layer (2, 148, 148a, 148b, 148c).
　本開示の態様３に係る波長変換素子（１０、３０、４０）は、上記の態様１または２において、前記基板（１）の第１の面上に配置された前記散乱層（３、３ｂ）が、前記ｚ軸正方向からの平面視において、前記基板（１）の第１の面側に配置された前記蛍光層（２、１４８、１４８ａ、１４８ｂ、１４８ｃ）を囲う側壁を構成する構成としてもよい。 The wavelength conversion element (10, 30, 40) according to the third aspect of the present disclosure is the scattering layer (3, 3b) arranged on the first surface of the substrate (1) in the above aspect 1 or 2. Is a configuration that constitutes a side wall surrounding the fluorescent layer (2, 148, 148a, 148b, 148c) arranged on the first surface side of the substrate (1) in a plan view from the z-axis positive direction. May be good.
　本開示の態様４に係る波長変換素子（３０、４０）は、上記の態様１～３の何れかにおいて、前記散乱層（３、３ｂ）が構成する前記側壁の内側面の少なくとも一部が、前記蛍光層（２、１４８、１４８ａ、１４８ｂ、１４８ｃ）の側面の少なくとも一部と接している構成としてもよい。 In any of the above aspects 1 to 3, the wavelength conversion element (30, 40) according to the fourth aspect of the present disclosure has at least a part of the inner side surface of the side wall formed by the scattering layer (3, 3b). It may be configured to be in contact with at least a part of the side surface of the fluorescent layer (2, 148, 148a, 148b, 148c).
　本開示の態様５に係る蛍光ホイールは、上記の態様１～４の何れかに記載の波長変換素子（１０、２０、３０、４０）の前記基板（１）がホイール（１４１）である蛍光ホイールであって、光源（１３）から出射された励起光（１４）が通過する前記ホイールの表面の周方向の少なくとも一部に、前記波長変換素子（１０、２０、３０、４０）が配置されている構成である。 The fluorescent wheel according to the fifth aspect of the present disclosure is a fluorescent wheel in which the substrate (1) of the wavelength conversion element (10, 20, 30, 40) according to any one of the above aspects 1 to 4 is a wheel (141). The wavelength conversion elements (10, 20, 30, 40) are arranged at least in the circumferential direction of the surface of the wheel through which the excitation light (14) emitted from the light source (13) passes. It is a configuration that has.
　本開示の態様６に係る光源装置（１０１）は、上記の態様５に記載の蛍光ホイールと、前記蛍光ホイールを回転させる駆動装置（１４２）と、前記波長変換素子（１０、２０、３０、４０）に励起光（１４）を照射する光源（１３）と、を備え、前記蛍光ホイールの回転に伴い、少なくとも前記蛍光ホイールの表面の周方向に配置された前記波長変換素子（１０、２０、３０、４０）の前記蛍光層（２、１４８、１４８ａ、１４８ｂ、１４８ｃ）に励起光（１４）が入射した際に、蛍光を出射する構成である。 The light source device (101) according to the sixth aspect of the present disclosure includes the fluorescent wheel according to the fifth aspect, a driving device (142) for rotating the fluorescent wheel, and the wavelength conversion element (10, 20, 30, 40). ) Is provided with a light source (13) that irradiates excitation light (14), and the wavelength conversion elements (10, 20, 30) are arranged at least in the circumferential direction of the surface of the fluorescent wheel as the fluorescent wheel rotates. , 40), when the excitation light (14) is incident on the fluorescent layer (2, 148, 148a, 148b, 148c), the fluorescence is emitted.
　本開示の態様７に係る車両用前照灯具は、上記の態様１～４の何れかに記載の波長変換素子（１０、２０、３０、４０）と、前記波長変換素子（１０、２０、３０、４０）に励起光を照射する光源と、前記波長変換素子（１０、２０、３０、４０）から出射した蛍光を反射させる反射面を有するリフレクタと、を備え、前記リフレクタの反射面が、入射した光を一定方向に平行に出射するように反射させる形状を有する構成である。 The vehicle headlights according to the seventh aspect of the present disclosure include the wavelength conversion element (10, 20, 30, 40) according to any one of the above aspects 1 to 4, and the wavelength conversion element (10, 20, 30). , 40) is provided with a light source for irradiating excitation light and a reflector having a reflecting surface for reflecting fluorescence emitted from the wavelength conversion elements (10, 20, 30, 40), and the reflecting surface of the reflector is incident. It has a shape that reflects the emitted light so as to be emitted in parallel in a certain direction.
　本開示の態様８に係る投影装置（１００）は、上記の態様６に記載の光源装置（１０１）と、表示素子（１０７）と、前記光源装置（１０１）からの光を前記表示素子（１０７）まで導光する光源側光学系（１０６）と、前記表示素子（１０７）からの投影光をスクリーンに投影する投影側光学系（１０８）と、を備える構成である。 The projection device (100) according to the eighth aspect of the present disclosure is the light source device (101), the display element (107), and the light from the light source device (101) according to the sixth aspect. ), And a projection side optical system (108) that projects the projected light from the display element (107) onto the screen.
　本開示の態様９に係る投影装置（１００）は、光源（１３）から出射された励起光（１４）が通過する周方向の少なくとも一部に、上記の態様１～４の何れかに記載の波長変換素子（１０、２０、３０、４０）が周方向に複数セグメントに分割されて配置された蛍光ホイールを備えた態様６に記載の光源装置（１０１）と、前記蛍光ホイールの回転位置を取得する回転位置センサ（１０３）と、前記回転位置センサ（１０３）からの出力情報に基づいて光源（１３）を制御する光源制御部（１０４）と、表示素子（１０７）と、前記光源装置（１０１）からの光を前記表示素子（１０７）まで導光する光源側光学系（１０６）と、前記表示素子（１０７）からの投影光をスクリーンに投影する投影側光学系（１０８）と、を備え、前記回転位置センサ（１０３）により取得された前記蛍光ホイールの回転位置の情報により光源（１３）の出力を制御する構成である。 The projection device (100) according to the ninth aspect of the present disclosure is described in any one of the above aspects 1 to 4 in at least a part of the circumferential direction through which the excitation light (14) emitted from the light source (13) passes. Acquires the light source device (101) according to aspect 6 and the rotational position of the fluorescent wheel, which includes a fluorescent wheel in which the wavelength conversion elements (10, 20, 30, 40) are divided into a plurality of segments in the circumferential direction. The rotating position sensor (103), the light source control unit (104) that controls the light source (13) based on the output information from the rotating position sensor (103), the display element (107), and the light source device (101). The light source side optical system (106) that guides the light from the display element (107) to the display element (107), and the projection side optical system (108) that projects the projected light from the display element (107) onto the screen. The output of the light source (13) is controlled by the information on the rotation position of the fluorescent wheel acquired by the rotation position sensor (103).
　本開示は上述した各実施形態に限定されるものではなく、請求項に示した範囲で種々の変更が可能であり、異なる実施形態にそれぞれ開示された技術的手段を適宜組み合わせて得られる実施形態についても本開示の技術的範囲に含まれる。さらに、各実施形態にそれぞれ開示された技術的手段を組み合わせることにより、新しい技術的特徴を形成することができる。
 

  The present disclosure is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the embodiments obtained by appropriately combining the technical means disclosed in the different embodiments. Is also included in the technical scope of the present disclosure. Furthermore, new technical features can be formed by combining the technical means disclosed in each embodiment.

Claims (9)

  1. 　平面形状を構成する第１の面を有する基板と、
    　前記基板の第１の面側に配置され、複数の蛍光体粒子を含み、励起光により蛍光を発する蛍光層と、
    　前記基板の第１の面上に配置され、前記蛍光層からの出射角度θ１が少なくとも第１の条件を満たす蛍光の一部を、第２の条件を満たす取出角度θ２にて出射する蛍光に方向転換させる散乱層と、
    を備え、
    　前記基板の第１の面から垂直に当該基板内部に向かう方向をｚ軸負方向とする３次元極座標において、
    　前記第1の条件は、ｚ軸正方向となす出射角度θ１が、π／２≦θ１＜πであり、
    　前記第２の条件は、ｚ軸正方向となす取出角度θ２が、０≦θ２＜π／２である
    ことを特徴とする波長変換素子。     A substrate having a first surface forming a planar shape,
    A fluorescent layer arranged on the first surface side of the substrate, containing a plurality of phosphor particles, and emitting fluorescence by excitation light.
    A part of the fluorescence that is arranged on the first surface of the substrate and whose emission angle θ1 from the fluorescent layer satisfies at least the first condition is directed toward the fluorescence that is emitted at the extraction angle θ2 that satisfies the second condition. The scattering layer to be converted and
    With
    In three-dimensional polar coordinates with the z-axis negative direction as the direction perpendicular to the inside of the substrate from the first surface of the substrate.
    The first condition is that the emission angle θ1 formed in the positive direction of the z-axis is π / 2 ≦ θ1 <π.
    The second condition is a wavelength conversion element characterized in that the extraction angle θ2 formed in the positive direction of the z-axis is 0 ≦ θ2 <π / 2.
  2. 　前記散乱層が前記基板の第１の面上に配置され、前記蛍光層が前記散乱層上に配置され、
    　前記ｚ軸と直交するｘｙ平面における前記散乱層の面積が、前記ｘｙ平面における前記蛍光層の面積よりも大きいことを特徴とする請求項１に記載の波長変換素子。     The scattering layer is arranged on the first surface of the substrate, and the fluorescent layer is arranged on the scattering layer.
    The wavelength conversion element according to claim 1, wherein the area of the scattering layer in the xy plane orthogonal to the z-axis is larger than the area of the fluorescent layer in the xy plane.
  3. 　前記基板の第１の面上に配置された前記散乱層が、前記ｚ軸正方向からの平面視において、前記基板の第１の面側に配置された前記蛍光層を囲う側壁を構成することを特徴とする請求項１または２に記載の波長変換素子。 The scattering layer arranged on the first surface of the substrate constitutes a side wall surrounding the fluorescent layer arranged on the first surface side of the substrate in a plan view from the positive direction of the z-axis. The wavelength conversion element according to claim 1 or 2.
  4. 　前記散乱層が構成する前記側壁の内側面の少なくとも一部が、前記蛍光層の側面の少なくとも一部と接していることを特徴とする請求項３に記載の波長変換素子。 The wavelength conversion element according to claim 3, wherein at least a part of the inner side surface of the side wall formed by the scattering layer is in contact with at least a part of the side surface of the fluorescent layer.
  5. 　請求項１～４の何れか一項に記載の波長変換素子の前記基板がホイールである蛍光ホイールであって、
    　光源から出射された励起光が通過する前記ホイールの表面の周方向の少なくとも一部に、前記波長変換素子が配置されていることを特徴とする蛍光ホイール。     A fluorescent wheel in which the substrate of the wavelength conversion element according to any one of claims 1 to 4 is a wheel.
    A fluorescent wheel characterized in that the wavelength conversion element is arranged in at least a part of the surface of the wheel in the circumferential direction through which the excitation light emitted from the light source passes.
  6. 　請求項５に記載の蛍光ホイールと、
    　前記蛍光ホイールを回転させる駆動装置と、
    　前記波長変換素子に励起光を照射する光源と、
    を備え、
    　前記蛍光ホイールの回転に伴い、少なくとも前記蛍光ホイールの表面の周方向に配置された前記波長変換素子の前記蛍光層に励起光が入射した際に、蛍光を出射することを特徴とする光源装置。     The fluorescent wheel according to claim 5 and
    The drive device that rotates the fluorescent wheel and
    A light source that irradiates the wavelength conversion element with excitation light,
    With
    A light source device that emits fluorescence when excitation light is incident on the fluorescent layer of the wavelength conversion element arranged at least in the circumferential direction of the surface of the fluorescent wheel as the fluorescent wheel rotates.
  7. 　請求項１～４の何れか一項に記載の波長変換素子と、
    　前記波長変換素子に励起光を照射する光源と、
    　前記波長変換素子から出射した蛍光を反射させる反射面を有するリフレクタと、
    を備えたことを特徴とする車両用前照灯具であって、
    　前記リフレクタの反射面が、入射した光を一定方向に平行に出射するように反射させる形状を有することを特徴とする車両用前照灯具。     The wavelength conversion element according to any one of claims 1 to 4,
    A light source that irradiates the wavelength conversion element with excitation light,
    A reflector having a reflecting surface that reflects the fluorescence emitted from the wavelength conversion element, and
    It is a vehicle headlight that is characterized by being equipped with
    A vehicle headlighting device, wherein the reflecting surface of the reflector has a shape that reflects incident light so as to be emitted in parallel in a certain direction.
  8. 　請求項６に記載の光源装置と、
    　表示素子と、
    　前記光源装置からの光を前記表示素子まで導光する光源側光学系と、
    　前記表示素子からの投影光をスクリーンに投影する投影側光学系と、
    を備えることを特徴とする投影装置。     The light source device according to claim 6 and
    Display element and
    A light source side optical system that guides light from the light source device to the display element, and
    A projection side optical system that projects the projected light from the display element onto the screen,
    A projection device characterized by comprising.
  9. 　光源から出射された励起光が通過する周方向の少なくとも一部に、請求項１～４の何れか一項に記載の波長変換素子が周方向に複数セグメントに分割されて配置された蛍光ホイールを備えた請求項６に記載の光源装置と、
    　前記蛍光ホイールの回転位置を取得する回転位置センサと、
    　前記回転位置センサからの出力情報に基づいて光源を制御する光源制御部と、
    　表示素子と、
    　前記光源装置からの光を前記表示素子まで導光する光源側光学系と、
    　前記表示素子からの投影光をスクリーンに投影する投影側光学系と、
    を備え、
    　前記回転位置センサにより取得された前記蛍光ホイールの回転位置の情報により光源の出力を制御することを特徴とする投影装置。

          A fluorescent wheel in which the wavelength conversion element according to any one of claims 1 to 4 is arranged in a plurality of segments in the circumferential direction in at least a part of the circumferential direction through which the excitation light emitted from the light source passes. The light source device according to claim 6 provided.
    A rotation position sensor that acquires the rotation position of the fluorescent wheel, and
    A light source control unit that controls the light source based on the output information from the rotation position sensor,
    Display element and
    A light source side optical system that guides light from the light source device to the display element, and
    A projection side optical system that projects the projected light from the display element onto the screen,
    With
    A projection device characterized in that the output of a light source is controlled by information on the rotational position of the fluorescent wheel acquired by the rotational position sensor.
PCT/JP2020/037833 2019-11-12 2020-10-06 Wavelength conversion element, fluorescent wheel, light source device, vehicle headlight, and projection device WO2021095397A1 (en)

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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013016268A (en) * 2011-06-30 2013-01-24 Sharp Corp Light-emitting device
JP2013228598A (en) * 2012-04-26 2013-11-07 Panasonic Corp Light source device and projection type display apparatus employing light source device
JP2015135455A (en) * 2014-01-20 2015-07-27 セイコーエプソン株式会社 Light source device and projector
JP2016012116A (en) * 2014-06-02 2016-01-21 カシオ計算機株式会社 Light source device and projection device
JP2016058624A (en) * 2014-09-11 2016-04-21 パナソニックＩｐマネジメント株式会社 Light-emitting device
JP2019066680A (en) * 2017-10-02 2019-04-25 株式会社小糸製作所 Wavelength conversion member and light source module
JP2019525389A (en) * 2016-06-22 2019-09-05 ルミレッズ ホールディング ベーフェー Light conversion package

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013016268A (en) * 2011-06-30 2013-01-24 Sharp Corp Light-emitting device
JP2013228598A (en) * 2012-04-26 2013-11-07 Panasonic Corp Light source device and projection type display apparatus employing light source device
JP2015135455A (en) * 2014-01-20 2015-07-27 セイコーエプソン株式会社 Light source device and projector
JP2016012116A (en) * 2014-06-02 2016-01-21 カシオ計算機株式会社 Light source device and projection device
JP2016058624A (en) * 2014-09-11 2016-04-21 パナソニックＩｐマネジメント株式会社 Light-emitting device
JP2019525389A (en) * 2016-06-22 2019-09-05 ルミレッズ ホールディング ベーフェー Light conversion package
JP2019066680A (en) * 2017-10-02 2019-04-25 株式会社小糸製作所 Wavelength conversion member and light source module

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