JP2012199061A - Light source device and lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source device in which color unevenness is not sensed due to a specular reflection component of excitation light to the sight of a human, eve in the case a phosphor plate is used as a reflection type.SOLUTION: The light source device 20 includes a solid light source 5 to emit visible light as excitation light and a phosphor plate 12 of reflection type including at least one kind of phosphors which is excited by excitation light from the solid light source 5 and emits fluorescence of longer wavelength than the emission wavelength of the solid light source 5. A rotation control means 3 is installed which exists in parallel to the plane of the reflection type phosphor plate 12 inside or on the plane of the phosphor plate 12 and rotates the phosphor plate 12 of reflection type at a prescribed rotation speed centered on a rotation shaft 4 orthogonal to the optical axis of the solid light source 5.

Description

  The present invention relates to a light source device and an illumination device.

  For example, Patent Document 1 proposes a light source device that realizes white light by combining a solid light source and a phosphor. FIG. 1 is a diagram showing a light source device of Patent Document 1. In FIG. Referring to FIG. 1, the light source device includes a dispersion 105 in which a light emitting element 101 that emits excitation light 110 that excites the phosphor 104 and a phosphor 104 that emits fluorescence 120 having a wavelength different from that of the excitation light 110 are dispersed. And a lead frame 106 that holds the light emitting element 101 and the dispersion 105, and at least part of the fluorescence emitted from the phosphor 104 in the dispersion 105 is from the incident side 105 a of the excitation light 110 in the dispersion 105. It comes to be taken out outside.

  Such a light source device has good luminous efficiency and color rendering, and is also useful as a light source for a vehicle headlamp or the like.

  In particular, a semiconductor light emitting element that emits blue excitation light as a solid light source and combined with a yellow phosphor plate has attracted attention as a light source for a next-generation vehicle headlamp or the like.

JP 2006-210887 A

  However, when the phosphor plate is used as a reflection type as in the light source device described above (the reflecting surface provided on the opposite side of the surface of the phosphor plate from which the excitation light from the solid light source is incident) The reflection light (specifically, fluorescence and excitation light) is extracted by using the reflection of light (in the case of using a reflection method), and, as will be described later, the excitation light from the solid light source is reflected by the reflective phosphor plate. The reflected light component (regular reflection component) in the reflection direction is partially intense on the projection surface, resulting in color unevenness. This phenomenon becomes more prominent when a reflecting member is provided on the back surface of the phosphor plate (the surface on the side opposite to the surface on which the excitation light from the solid light source is incident).

  An object of the present invention is to provide a light source device and an illuminating device that do not cause color unevenness due to a regular reflection component of excitation light to human vision even when a phosphor plate is used as a reflection type.

  In order to achieve the above object, the invention described in claim 1 includes a solid-state light source that emits visible light as excitation light, and fluorescence that is excited by excitation light from the solid-state light source and has a longer wavelength than the emission wavelength of the solid-state light source. A reflective phosphor plate including at least one type of phosphor that emits light, wherein the reflective phosphor plate is parallel to a plane of the reflective phosphor plate and Rotation control means for rotating at a predetermined rotation speed around a rotation axis that exists in or on a reflection type phosphor plate and is orthogonal to the optical axis of the solid-state light source is provided. Yes.

  According to a second aspect of the present invention, in the light source device according to the first aspect, the reflection-type phosphor plate is arranged on both sides of the reflection member with the reflection member interposed therebetween. It is characterized by that.

  The invention described in claim 3 is a solid light source that emits visible light as excitation light, and at least one type that emits fluorescence having a wavelength longer than the emission wavelength of the solid light source when excited by excitation light from the solid light source. A reflection-type phosphor plate including the phosphor, and the reflection-type phosphor plate is used so that excitation light from the solid-state light source is incident only on the phosphor plate. Reciprocating rotation at a predetermined speed around a rotation axis that exists in or on the reflection type phosphor plate parallel to the plane of the reflection type phosphor plate and is orthogonal to the optical axis of the solid state light source The rotary reciprocating motion control means is provided.

  According to a fourth aspect of the present invention, there is provided an illuminating device in which the light source device according to any one of the first to third aspects is used.

  According to the first, second, and fourth aspects of the present invention, a solid-state light source that emits visible light as excitation light, and a wavelength longer than the emission wavelength of the solid-state light source that is excited by excitation light from the solid-state light source. And a reflection type phosphor plate including at least one kind of phosphor that emits the fluorescence of the reflection type phosphor plate, the reflection type phosphor plate being parallel to a plane of the reflection type phosphor plate Therefore, there is provided a rotation control means for rotating at a predetermined rotation speed around a rotation axis that is present in the reflection type phosphor plate or on a plane and orthogonal to the optical axis of the solid state light source. Even when the phosphor plate is used as a reflection type, it is possible to prevent the human eye from feeling color unevenness due to the regular reflection component of the excitation light.

  According to the third and fourth aspects of the invention, the solid-state light source that emits visible light as excitation light, and the fluorescence that is excited by the excitation light from the solid-state light source and has a longer wavelength than the emission wavelength of the solid-state light source. A reflection type phosphor plate containing at least one type of phosphor that emits light, wherein the reflection type of the excitation light from the solid light source is incident only on the phosphor plate. The phosphor plate is parallel to the plane of the reflection type phosphor plate and exists in or on the reflection type phosphor plate and is centered on a rotation axis perpendicular to the optical axis of the solid light source. Rotation and reciprocation control means for rotating and reciprocating at a speed of 5 mm is provided, so that even when the phosphor plate is used as a reflection type, human eyes do not feel uneven color due to the regular reflection component of excitation light. It can be, and can be prevented to reduce the extraction efficiency of the reflected light (efficiency) of the phosphor plate.

It is a figure which shows the light source device of patent document 1. FIG. It is a figure which shows the example of 1 structure of the light source device of this invention. It is a figure which shows the position range of a reflection type fluorescent substance plate. It is a figure which shows the position range of a reflection type fluorescent substance plate. It is a figure for demonstrating the color nonuniformity by the regular reflection component of the excitation light which arises when a reflection type fluorescent substance plate is fixed. It is a figure which shows the light distribution at the time of fixing a reflection type fluorescent substance plate as shown in FIG. It is a figure which shows the example of the appearance position of the blue regular reflection component which changes by rotating a reflection type phosphor plate centering around a rotating shaft. It is a figure which shows the other structural example of the light source device of this invention. It is a figure for demonstrating operation | movement of the light source device of FIG. It is a figure which shows the other structural example of the light source device of this invention. It is a figure for demonstrating operation | movement of the light source device of FIG. It is a figure which shows an example of the illuminating device using the light source device of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIGS. 2A and 2B are diagrams showing a configuration example of the light source device of the present invention. 2A is a front view, and FIG. 2B is a plan view.

  Referring to FIGS. 2A and 2B, the light source device 20 includes a solid light source 5 that emits visible light as excitation light, and an emission wavelength of the solid light source 5 that is excited by the excitation light from the solid light source 5. And a reflective phosphor plate 12 including at least one kind of phosphor that emits fluorescence having a longer wavelength.

  Here, the reflection type phosphor plate 12 is reflected using reflection by a reflection surface provided on the opposite side of the surface of the phosphor plate 2 from the surface on which the excitation light from the solid light source 5 is incident. 2 is a phosphor plate configured to extract light (specifically, fluorescence and excitation light). In the examples of FIGS. 2A and 2B, as shown in FIG. A reflective member 6 is provided on the back surface (surface that functions as a reflective surface) of the plate 2 to form a reflective phosphor plate 12. In other words, in the example of FIGS. 2A and 2B, the reflective phosphor plate 12 has the reflective member 6 provided on the back surface (surface that functions as a reflective surface) of the phosphor plate 2. It has become.

  Moreover, it is preferable to use the phosphor plate 2 that does not substantially contain a resin component. That is, when a phosphor plate 2 that does not substantially contain a resin component is used, there is no discoloration due to heat and light absorption is small, so that it is possible to further increase the brightness.

  The phosphor plate 2 substantially free of a resin component means that the resin component normally used for forming the phosphor plate is 5 wt% or less of the phosphor plate. As a material for realizing such a phosphor plate, a phosphor powder dispersed in glass, a glass phosphor in which a luminescent center ion is added to a glass matrix, a phosphor single crystal, and a phosphor polycrystalline (hereinafter referred to as a phosphor) And phosphor ceramics). The phosphor ceramic is a lump of phosphor that is formed by firing a material into an arbitrary shape before firing in the phosphor manufacturing process. Phosphor ceramics may use an organic substance as a binder in the molding process during the manufacturing process. However, an organic resin component is included in the fired phosphor ceramic because a degreasing process is provided after molding to burn off the organic components. Remains only 5 wt% or less. Therefore, since the phosphor plate mentioned here does not substantially contain a resin component and is composed only of an inorganic substance, it does not cause discoloration due to heat. In addition, glass or ceramics made of only an inorganic substance generally has a higher thermal conductivity than a resin, and is therefore advantageous in heat dissipation from the phosphor plate 2 to the reflecting member 6. In particular, phosphor ceramics generally have higher thermal conductivity than glass and are less expensive to manufacture than single crystals. Therefore, it is preferable to use them for the phosphor plate 2.

  The phosphor plate 2 includes at least one kind of phosphor that is excited by excitation light from the solid light source 5 and emits fluorescence having a longer wavelength than the emission wavelength of the solid light source 5. Specifically, when the solid-state light source 5 emits blue light as visible light, the phosphor plate 2 includes at least one kind of phosphor among phosphors such as green, red, and yellow. It is out. When the solid light source 5 emits blue light as visible light, when the phosphor plate 2 includes, for example, green and red phosphors (each of the green and red phosphors is uniformly dispersed, for example) In the case of being mixed), when the phosphor plate 2 is irradiated with blue light from the solid light source 5, illumination light such as white can be obtained as reflected light. When the solid light source 5 emits blue light as visible light, for example, when the phosphor plate 2 includes only a yellow phosphor, the blue light from the solid light source 5 is emitted from the phosphor plate 2. When illuminating, illumination light such as white can be obtained as reflected light.

  Incidentally, as described above, when the phosphor plate 2 is used as a reflection type (the reflecting surface provided on the opposite side of the surface of the phosphor plate 2 from the surface on which the excitation light from the solid light source 5 is incident). The reflection light (specifically, in the case of using a method (reflection method) for extracting reflected light and excitation light) using reflection by the light source), as will be described in detail later, excitation light from the solid light source 5 by the phosphor plate 2 The reflected light component (regular reflection component) in the regular reflection direction partially appears strongly on the projection surface, resulting in color unevenness (for example, strong color unevenness in blue). This phenomenon becomes more prominent when the reflecting member 6 is provided on the back surface of the phosphor plate 2 (the surface opposite to the surface on which the excitation light from the solid light source 5 is incident).

  In the light source device 20 of FIGS. 2A and 2B, even when the phosphor plate 2 is used as a reflection type, in order to prevent the human eye from feeling color unevenness due to the regular reflection component of the excitation light, The reflection type phosphor plate 12 is present on the rotation axis 4 (in parallel to the plane of the reflection type phosphor plate 12 or in or on the plane of the reflection type phosphor plate 12 (on the plane of the reflection type phosphor plate 12)). In addition, a rotation control means 3 is provided that rotates at a predetermined rotation speed (for example, rotates in the direction of arrow R) around the rotation axis 4 orthogonal to the optical axis of the solid light source 5. 2A and 2B, a motor is used for the rotation control means 3, the rotation shaft 4 is connected to the rotation control means (motor) 3, and the reflective phosphor plate 12 is The rotation control means (motor) 3 rotates around the rotation shaft 4 (note that the rotation control means (motor) 3 is not shown in FIG. 2B).

  The reflecting member 6 and the rotating shaft 4 are made of, for example, metal. When the reflecting member 6 and the rotating shaft 4 are made of metal, the rotating plate 4 is formed integrally with the reflecting member 6 so that the phosphor plate is formed. 2 can efficiently conduct and dissipate heat generated when the excitation light from the solid light source 5 is irradiated to the light 2 (heat generated when the phosphor plate 2 is excited).

  Further, in the light source device 20 of FIGS. 2A and 2B, the timing of taking out and using the reflected light (specifically, fluorescence and excitation light) from the phosphor plate 2 is the same as that for the solid light source 5. For example, the phosphor plate 2 is limited to a position range of 90 ° (first quadrant) as shown in FIG. 3A, that is, a position range of P1 to P2. Even when the excitation light is irradiated, the phosphor plate 2 with respect to the solid light source 5 has a 90 ° position range (second quadrant) as shown in FIG. When in the position range of P3, the reflected light (specifically, fluorescence and excitation light) from the phosphor plate 2 is not taken out and used.

  Further, the predetermined rotational speed of the reflection type phosphor plate 12 does not need to be constant, and the phosphor plate 2 is positioned with respect to the solid light source 5 in a 90 ° position range (for example, as shown in FIG. In the first quadrant), the predetermined rotational speed is preferably a speed at which the time resolution of the human eye cannot follow, for example, a speed of 30 Hz or more per rotation. Even when the excitation light is irradiated, when the phosphor plate 2 is in a 90 ° position range (second quadrant) as shown in FIG. Alternatively, when the excitation light from the solid light source 5 is applied to the back surface of the reflective phosphor plate 12 (the surface of the reflective member 6) or the side surface of the reflective phosphor plate 12 as shown in FIG. , Not related to phosphor excitation Therefore, excitation at the phosphor plate 2 is made efficient by making the rotation speed at that time faster than when the phosphor plate 2 is in the 90 ° position range (first quadrant) as shown in FIG. Can be done well. 2A and 2B, the back surface (surface of the reflection member 6) of the reflective phosphor plate 12 is reflected light (blue) on the back surface (surface of the reflection member 6). In order to prevent the occurrence of color unevenness due to the above, it is desirable to perform a process so as not to reflect the light from the solid light source 5.

  The light source device 20 shown in FIGS. 2A and 2B will be described in more detail.

  In the light source device 20 shown in FIGS. 2A and 2B, a light emitting diode or a semiconductor laser having a light emission wavelength in the visible light region can be used as the solid light source 5.

More specifically, in the light source device 20 of FIGS. 2A and 2B, the solid-state light source 5 includes, for example, a light emitting diode or semiconductor that emits blue light having a light emission wavelength of about 460 nm using a GaN-based material. A laser or the like can be used. In this case, the phosphor of the phosphor plate 2 is excited by blue light having a wavelength of about 440 nm to about 470 nm. For example, the red phosphor includes CaAlSiN ₃ : Eu ²⁺ , Ca ₂ Si ₅ N _8. : Eu ²⁺ , KSiF ₆ : Mn ⁴⁺ , KTiF ₆ : Mn ⁴⁺ can be used, and Y ₃ (Ga, Al) ₅ O ₁₂ : Ce ³⁺ , Ca ₃ Sc ₂ Si ₃ O ₁₂ can be used as a green phosphor. : Ce ³⁺ , CaSc ₂ O ₄ : Eu ²⁺ , (Ba, Sr) ₂ SiO ₄ : Eu ²⁺ , Ba ₃ Si ₆ O ₁₂ N ₂ : Eu ²⁺ , (Si, Al) ₆ (O, N) ₈ : Eu or the like can be used ^2+, the yellow ^{_{phosphor, Y 3 Al 5 O 12:}} Ce 3+ (YAG), (Sr, Ba) 2 SiO 4: Eu 2+, Ca x (Si, a _{) 12 (O, N) 16} : Eu 2+ or the like can be used.

As the phosphor plate 2, a phosphor in which these phosphor powders are dispersed in glass, a glass phosphor in which a luminescent center ion is added to a glass matrix, a phosphor ceramic not including a binding member such as a resin, or the like is used. Can do. As a specific example of the phosphor powder dispersed in glass, the phosphor powder having the composition listed above is contained in a glass containing components such as P ₂ O ₃ , SiO ₂ , B ₂ O ₃ , and Al ₂ O _3. Are dispersed. Examples of glass phosphors in which a luminescent center ion is added to a glass matrix include Ca—Si—Al—O—N and Y—Si—Al—O—N systems in which Ce ³⁺ or Eu ²⁺ is added as an activator. Examples thereof include oxynitride glass phosphors. Examples of the phosphor ceramic include a sintered body having a phosphor composition having the composition listed above and substantially not including a resin component. Among these, it is desirable to use a phosphor ceramic having translucency. This is a phosphor ceramic that has translucency because there are almost no pores or impurities at grain boundaries that cause light scattering in the sintered body. Since pores and impurities can also prevent thermal diffusion, translucent ceramics exhibit high thermal conductivity. For this reason, when used as the phosphor plate 2, the excitation light and fluorescence can be taken out from the phosphor plate 2 without being lost by diffusion, and the heat generated in the phosphor plate 2 can be efficiently dissipated. Even a sintered body that does not show translucency is desirable to have as few pores and impurities as possible. As an index for evaluating the remaining amount of pores, the value of specific gravity of the phosphor ceramic can be used, and it is desirable that the value is 95% or more with respect to the theoretical value by which the value is calculated.

Here, a method of manufacturing a phosphor ceramic having translucency will be described by taking as an example a Y ₃ Al ₅ O ₁₂ : Ce ³⁺ phosphor which is a blue-excited yellow light-emitting phosphor. The phosphor ceramic is manufactured through a starting material mixing step, a forming step, a firing step, and a processing step. As starting materials, yttrium oxide, cerium oxide, alumina, and the like, oxides of constituent elements of Y ₃ Al ₅ O ₁₂ : Ce ³⁺ phosphor, carbonates, nitrates, sulfates and the like that become oxides after firing are used. The particle size of the starting material is preferably a submicron size. These raw materials are weighed so as to have a stoichiometric ratio. At this time, for the purpose of improving the transmittance of the ceramic after firing, it is also possible to add a compound such as calcium or silicon. The weighed raw materials are sufficiently dispersed and mixed by a wet ball mill using water or an organic solvent. Next, the mixture is formed into a predetermined shape. As the molding method, a uniaxial pressing method, a cold isostatic pressing method, a slip casting method, an injection molding method, or the like can be used. The obtained molded body is fired at 1600 to 1800 ° C. Thus, translucent ^{_{Y 3 Al 5 O 12: Ce}} 3+ phosphor ceramic can be obtained.

  The phosphor ceramic produced as described above is polished to a thickness of several tens to several hundreds of μm using an automatic polishing apparatus and the like, and is further rounded by dicing or scribing using a diamond cutter or laser. Cut out to a board of any shape such as a square, fan or ring.

  Further, as the reflecting member 6, a metal substrate, oxide ceramics, non-oxidized ceramics, or the like can be used, but it is desirable to use a metal substrate having particularly high heat transfer characteristics and workability. As the metal, simple substances such as Al, Cu, Ti, Si, Ag, Au, Ni, Mo, W, Fe, Pd, and alloys containing them can be used. Further, the surface of the reflecting member 6 may be coated for the purpose of increasing reflection and preventing corrosion. Further, a structure in which a metal film is directly attached to the back surface of the phosphor plate 2 may be used, but a metal substrate having a certain thickness is more suitable in consideration of the problem of heat sinking.

  Moreover, an organic adhesive, an inorganic adhesive, low melting glass, brazing, etc. can be used for joining the phosphor plate 2 and the reflecting member 6. Among these, it is desirable to use brazing that can achieve both high reflectance and heat transfer characteristics. The ceramic (phosphor plate 2) and the metal substrate (reflecting member 6) can be joined by first forming a metal film on the ceramic side and brazing the metal film and the metal substrate. The metal film can be formed on the ceramic by a vacuum deposition method, a sputtering method, a refractory metal method, or the like. The refractory metal method is a method in which an organic binder containing metal fine particles is applied to the surface of a ceramic and heated to 1000 to 1700 ° C. in a reducing atmosphere containing water vapor and hydrogen. For the metal film formed at this time, a simple substance or an alloy containing Si, Nb, Ti, Zr, Mo, Ni, Mn, W, Fe, Pt, Al, Au, Pd, Ta, Cu, or the like is used. As the brazing material, a brazing material containing Ag, Cu, Zn, Ni, Sn, Ti, Mn, In, Bi, or the like can be used. If necessary, the oxide film on the joining surface of the metal film and the metal can be removed with a flux, a brazing material is disposed on the joining surface, heated to 200 to 800 ° C., and cooled to be joined. Further, in order to prevent destruction of the joint surface due to the difference in expansion coefficient between the ceramic and the metal after joining, the joining may be performed with a substance having an intermediate expansion coefficient between the ceramic and the metal interposed.

  Here, in the light source device 20 shown in FIGS. 2A and 2B, the principle of preventing the human vision from causing color unevenness due to the regular reflection component of the excitation light will be described. In the following, as an example, the solid light source 5 is a semiconductor laser that emits blue light as excitation light, and the phosphor plate 2 is a phosphor that is excited by blue light and emits yellow fluorescence. explain.

  When the reflective phosphor plate 12 is used as in the light source device 20 of FIGS. 2A and 2B, when the reflective phosphor plate 12 is fixed, as schematically shown in FIG. The direction in which the incident angle and the emission angle of the excitation light from the solid light source 5 to the phosphor plate 2 are equal around the normal direction z of the phosphor plate 2 (that is, the regular reflection direction of the excitation light from the solid light source 5) ) Emitted from the solid-state light source 5 (excitation light (blue)). This is because light from the solid light source 5 (excitation light (blue)) causes regular reflection on the surface of the phosphor plate 2 or light from the solid light source 5 that does not excite the phosphor (excitation light (blue)) is fluorescent. This is because regular reflection is caused by the reflecting member 6 disposed on the back surface of the body plate 2. On the other hand, the fluorescence from the phosphor excited by the light (excitation light) from the solid light source 5 becomes a Lambertian light distribution centering on the normal direction z of the phosphor plate 2 and seen from various directions. The brightness is almost equal. Therefore, when an attempt is made to obtain white by additive color mixing of these two lights (excitation light reflected by the phosphor plate 2 (blue) and phosphor fluorescence (yellow)), depending on the direction, blue light and yellow light The balance changes and color unevenness occurs. In particular, in the specular reflection direction of the incident light (excitation light) from the solid light source 5 on the phosphor plate 2, the blue of the excitation light from the solid light source 5 is strongly emitted, resulting in severe color unevenness.

  FIG. 6 shows the light distribution when the reflective phosphor plate 12 is fixed as shown in FIG. As shown in FIG. 6, when the projection surface 70 is irradiated with the reflected light from the phosphor plate 2, the regular reflection component of the excitation light (blue light) is collectively irradiated to a certain band-like portion 71, and this portion 71. As a result, color unevenness (color unevenness with strong blue color) due to the regular reflection component of excitation light (blue light) occurs. It should be noted that portions other than the band-shaped portion 71 of the projection surface 70 are normal (color unevenness) due to color mixing of excitation light (blue light) and fluorescence (yellow light) from the phosphor plate (yellow phosphor plate) 2. No) It is white.

  In the present invention, the appearance position of color unevenness due to the reflected light component (that is, the blue regular reflection component) in the regular reflection direction of the incident light (excitation light) from the solid-state light source 5 on the phosphor plate 2 is represented by the reflection type fluorescence. By rotating the body plate 12 around the rotation axis 4, the body plate 12 is changed (changed) with time. 7A, 7 </ b> B, and 7 </ b> C show examples of the appearance position of the color irregularity 71 of the blue regular reflection component that changes by rotating the reflective phosphor plate 12 around the rotation axis 4. It is shown. In this way, by rotating the reflective phosphor plate 12 around the rotation axis 4, the appearance position of the color irregularity 71 of the blue regular reflection component is temporally changed (differentiated), and the blue regular reflection is obtained. By causing the appearance positions of the component color unevenness 71 to be scattered (that is, to disperse the color unevenness 71 due to the blue regular reflection component), the color unevenness 71 due to the regular reflection component of the excitation light in human vision. It can be made not to feel. When the reflection-type phosphor plate 12 rotates slowly, a temporal change in blue light (that is, color irregularity 71 of the blue regular reflection component) is visually recognized. When the rotation speed around the rotation axis 4 increases and the rotation speed cannot be followed by the time resolution of the human eye (specifically, when the rotation speed is 30 Hz or more per rotation), the color unevenness 71 can no longer be seen. The object of the present invention can be achieved.

  FIGS. 8A and 8B are diagrams showing another configuration example of the light source device of the present invention. In FIGS. 8 (a) and 8 (b), the same parts as those in FIGS. 2 (a) and 2 (b) are denoted by the same reference numerals. In the light source device 20 of FIGS. 2A and 2B, the phosphor plate 2 is provided on one surface of the reflecting member 6 to form the reflective phosphor plate 12, but FIG. , (B), the phosphor plates 2a and 2b are respectively provided on both surfaces of the reflecting member 6 to form a reflecting phosphor plate 22 (the composition of the phosphor plates 2a and 2b). Etc., the joining of the phosphor plates 2a, 2b and the reflecting member 6 are the composition of the phosphor plate 2 in FIGS. 2 (a) and 2 (b), the joining of the phosphor plate 2 and the reflecting member 6, etc. Is the same). In the case of the light source device 30 shown in FIGS. 8A and 8B, the rotation control means 3 causes the reflection type phosphor plate 22 to be parallel to the rotation axis 4 (the plane of the reflection type phosphor plate 22). And a predetermined rotation centering on the rotation axis 4 which exists in the reflection type phosphor plate 22 or on the plane (on the plane of the reflection type phosphor plate 22) and which is orthogonal to the optical axis of the solid light source 5. It is designed to rotate at speed. More specifically, in the case of the light source device 30 in FIGS. 8A and 8B, the phosphor plate 2 a is in a 90 ° position range as shown in FIG. (First quadrant), that is, when the phosphor plate 2b is in the position range of P1 to P2, for example, the 90 ° position range (first quadrant) as shown in FIG. 9B, that is, the position of P1 to P2. When it is within the range, the predetermined rotational speed is a speed that the time resolution of the human eye cannot follow, for example, a speed of 30 Hz or more per rotation, and in other cases, by making the rotational speed faster, Excitation with the phosphor plates 2a and 2b can be performed efficiently. Further, in the light source device 30 of FIGS. 8A and 8B, the phosphor plates 2a and 2b are provided on both surfaces of the reflecting member 6, respectively, so that the light source device 20 of FIGS. As compared with the above, the usage frequency of the phosphor plate can be doubled, and the extraction efficiency of the reflected light from the phosphor plate by the irradiation light from the solid light source 5 can be doubled. Further, the reflecting member 6 is made of a metal plate, and the rotating shaft 4 is provided integrally with the metal plate, whereby the heat generated when the phosphor plate is excited can be efficiently conducted and dissipated.

  FIGS. 10A and 10B are diagrams showing another configuration example of the light source device of the present invention. In FIGS. 10A and 10B, the same parts as those in FIGS. 2A and 2B are denoted by the same reference numerals. In the light source device 20 of FIGS. 2 (a) and 2 (b), the rotation control means 3 rotates the reflective phosphor plate 12 in the direction of arrow R (in one direction), for example. In the light source device 40 of (a) and (b), instead of the rotation control means 3, the reflective phosphor plate 12 is rotated so that the excitation light from the solid light source 5 is incident only on the phosphor plate 2. An axis 4 (parallel to the plane of the reflective phosphor plate 12 and present in or on the reflective phosphor plate 12 (on the plane of the reflective phosphor plate 12) and the optical axis of the solid light source 5 Is provided with a rotational reciprocating motion control means 7 that rotates and reciprocates at a predetermined speed around the rotational axis 4 orthogonal to the rotational axis 4 (not shown in FIG. 10B). Have been). Here, a motor or the like is used as the rotational reciprocating motion control means 7, and the rotational reciprocating motion speed by the rotational reciprocating motion control means 7 is a speed at which the time resolution of the human eye cannot follow, for example, 30 Hz or more per reciprocating rotational speed. Is preferred. In the light source device 40 of FIGS. 10A and 10B, the phosphor plate 2 is positioned relative to the solid light source 5 at a 90 ° position range (first quadrant) as shown in FIG. By rotating and reciprocating within the position range of P2, the extraction efficiency (utilization efficiency) of the reflected light from the phosphor plate 2 can be significantly increased as compared with the cases of FIGS. 2 (a) and 2 (b). In other words, in the light source device 40 shown in FIGS. 10A and 10B, even when the phosphor plate 2 is used as a reflection type, human eyes do not feel color unevenness due to the regular reflection component of the excitation light. In addition, the extraction efficiency (utilization efficiency) of reflected light from the phosphor plate 2 can be prevented from being lowered.

  In each configuration example described above, the phosphor plate 2 is in a 90 ° position range (first quadrant) as shown in FIG. 3A with respect to the solid-state light source 5, that is, a position range of P1 to P2. The reflected light (specifically, fluorescence and excitation light) from the phosphor plate 2 is sometimes taken out and used. However, the phosphor plate 2 has a 90 ° position range (the first position shown in FIG. 3A). (1 quadrant), that is, in the position range of P1 to P2, the reflected light (specifically, fluorescence and excitation light) from the phosphor plate 2 is not taken out and used, and the solid light source 5 is fluorescent. When the body plate 2 is in the 90 ° position range (second quadrant) as shown in FIG. 3B, that is, in the position range of P2 to P3, the reflected light from the phosphor plate 2 (specifically, (Fluorescence and excitation light) It is also possible. In this case, in the light source device 40 of FIGS. 10A and 10B, the phosphor plate 2 is positioned relative to the solid light source 5 at a 90 ° position range (second quadrant) as shown in FIG. 3B, for example. That is, it is also possible to perform reciprocating rotation mainly within the position range of P2 to P3.

  In addition, the above-described light source devices 20, 30, and 40 of the present invention can be combined with a lens system or a reflecting plate to realize a lighting device.

  FIG. 12 shows an example of a lighting device using the light source device of the present invention. Referring to FIG. 12, the illumination device 50 includes a case 51, a light source device (for example, 20, 30, or 40) housed in the case 51, and a light source device (for example, 20, 30, or 40), and the like, and a lens system 52 that irradiates forward with a predetermined light distribution characteristic.

  In the illumination device 50 of FIG. 12, a light source device (for example, 20, 30, or 40) is used, so that it is possible to obtain illumination light that does not cause color unevenness due to the regular reflection component of excitation light to human vision. it can.

  The present invention can be used for vehicle lighting such as headlamps, projectors, and general lighting.

2, 2a, 2b Phosphor plate 3 Rotation control means 4 Rotating shaft 5 Solid light source 6 Reflective member 7 Rotational reciprocation control means 12, 22 Reflective phosphor plate 20, 30, 40 Light source device 50 Illumination device 51 Case 52 Lens system

Claims (4)

A reflective phosphor including a solid-state light source that emits visible light as excitation light, and at least one phosphor that is excited by excitation light from the solid-state light source and emits fluorescence having a longer wavelength than the emission wavelength of the solid-state light source A light source device comprising: a plate, wherein the reflective phosphor plate is present in or on the reflective phosphor plate parallel to a plane of the reflective phosphor plate; and A light source device comprising a rotation control means for rotating at a predetermined rotation speed about a rotation axis orthogonal to the optical axis of the solid light source. The light source device according to claim 1, wherein the reflection type phosphor plate has phosphor plates arranged on both sides of the reflection member with a reflection member interposed therebetween. A reflective phosphor including a solid-state light source that emits visible light as excitation light, and at least one phosphor that is excited by excitation light from the solid-state light source and emits fluorescence having a longer wavelength than the emission wavelength of the solid-state light source A light source device including a plate, wherein the reflective phosphor plate is parallel to a plane of the reflective phosphor plate so that excitation light from the solid light source is incident only on the phosphor plate. And a reciprocating motion control means for reciprocating at a predetermined speed around a rotational axis that is present in or on a plane of the reflective phosphor plate and is orthogonal to the optical axis of the solid state light source. A light source device characterized by comprising: An illumination device, wherein the light source device according to any one of claims 1 to 3 is used.

Images