JP2013161561A - Light source device and lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent such irradiation unevennesses (color shading) as yellow rings, in a light source device equipped with a solid light source emitting as excitation light of a given wavelength out of a wavelength band of visible light, and a phosphor layer including at least one kind of phosphor excited by the excitation light from the light source and emitting fluorescence of a wavelength longer than an emission wavelength of the solid light source.SOLUTION: The phosphor layer 2 is formed as a two-dimensional array structure of micro convex bodes 7, with a size of each micro convex 7 of the phosphor layer 2 smaller than a size of a beam spot (a beam spot radius) of the excitation light from the solid light source 5 on the phosphor layer 2.

Description

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

  Conventionally, for example, in Patent Document 1, as shown in FIG. 1, an LED module 103 that emits blue light as excitation light, and a phosphor layer 104 that is excited by excitation light from the LED module 103 and emits yellow light fluorescence, In the light source device intended to generate white light by mixing blue light and yellow light, the blue light from the LED module 103 is transmitted between the LED module 103 and the phosphor layer 104 and fluorescent. There has been proposed a method of improving the light utilization efficiency by disposing a wavelength selective filter 106 that reflects yellow light emitted from the body layer 104. In FIG. 1, reference numeral 108 denotes a phosphor fixing transparent body, and reference numeral 107 denotes light (excitation light (blue light), fluorescence (yellow light)) extracted from the light extraction surface 104a of the phosphor layer 104. .

JP 2009-266437 A

  In the configuration of FIG. 1, the blue light from the LED module 103 passes through the phosphor fixing transparent body 108 and the wavelength selection filter 106 and then enters the phosphor layer 104. Part of the excitation light (blue light) incident on the phosphor layer 104 is transmitted through the phosphor layer 104 and emitted from the light extraction surface 104a of the phosphor layer 104, while the other part is phosphor layer 4. Or used for excitation of fluorescence (yellow light), or reflected by the light extraction surface 104 a toward the wavelength selection filter 106 and transmitted through the wavelength selection filter 106. Therefore, the blue light from the LED module 103 is mainly emitted from the portion (excitation light irradiation spot) irradiated with the excitation light (blue light) of the phosphor layer 104.

  On the other hand, the emission of yellow light from the phosphor layer 104 is isotropic, part of the yellow light is emitted from the light extraction surface 104a of the phosphor layer 104, while the other part is light extraction. The light is reflected by the surface 104 a and travels toward the wavelength selection filter 106 and is selectively reflected by the wavelength selection filter 106. Then, a part of the reflected light of the yellow light selectively reflected by the wavelength selection filter 106 is emitted from the light extraction surface 104a, and another part of the light is reflected by the extraction surface 104a to select the wavelength. It becomes so-called multiple reflected light that is directed toward the filter 106 and selectively reflected by the wavelength selection filter 106. Therefore, yellow light is emitted from the entire phosphor layer 104, and the emission of yellow light from the peripheral portion becomes stronger by the wavelength selection filter 106.

  In order to facilitate assembly, the phosphor layer 104 is preferably larger than the excitation light irradiation spot. However, in this case, the yellow light emission region having the entire phosphor layer 104 as the emission region is larger than the blue light emission region having almost the same size as the excitation light irradiation spot. FIG. 2 is a diagram showing the light emission state of the phosphor layer 104. In FIG. 2, in the region 110 having a size almost the same as the excitation light irradiation spot, white light is generated due to the color mixture of blue light and yellow light. In the region 111 outside the region 110 having the same size as the light irradiation spot, yellow light is generated.

  Therefore, in the illumination device as shown in FIG. 3 that enlarges and projects the light source device of FIG. 1 onto a predetermined projection surface using a lens system or the like, the projection surface reflects the color variation of the light source, and the central portion is There was a problem that uneven irradiation (color unevenness) in which the peripheral portion was yellow and yellow occurred (this irradiation unevenness (color unevenness) was called a yellow ring). In FIG. 3, reference numeral 102 denotes a lens system, and reference numeral 105 denotes a projection plane.

  The present invention includes a solid-state light source that emits light having a predetermined wavelength in the visible light wavelength region as excitation light, and fluorescence that is excited by excitation light from the solid-state light source and has a wavelength longer than the emission wavelength of the solid-state light source. Provided are a light source device and an illuminating device capable of preventing the occurrence of irradiation unevenness (color unevenness) such as a yellow ring in a light source device including a phosphor layer including at least one type of phosphor that emits light. The purpose is that.

In order to achieve the above object, the invention described in claim 1 is a solid-state light source that emits light having a predetermined wavelength in a visible light wavelength region as excitation light, and is excited by excitation light from the solid-state light source. A light source device including a phosphor layer including at least one kind of phosphor that emits fluorescence having a wavelength longer than the emission wavelength of a solid-state light source,
The phosphor layer is formed as a two-dimensional array structure of minute convex bodies, and the size of each minute convex body in the phosphor layer is determined by the excitation light from the solid light source on the phosphor layer. It is characterized by being smaller than the size of the beam spot.

  According to a second aspect of the present invention, in the light source device according to the first aspect, the light source device is a transmissive type, the phosphor layer is provided on a transparent substrate, and the phosphor layer and the transparent Between the substrate, there is provided a wavelength selection means having a characteristic of transmitting excitation light from the solid-state light source and reflecting fluorescence from the phosphor layer.

  The invention described in claim 3 is an illumination device characterized in that the light source device described in claim 1 or claim 2 is used.

  According to the first to third aspects of the invention, the solid-state light source that emits light having a predetermined wavelength in the visible light wavelength region as the excitation light, and the solid-state light source that is excited by the excitation light from the solid-state light source. And a phosphor layer containing at least one type of phosphor that emits fluorescence having a longer wavelength than the emission wavelength of the light source, wherein the phosphor layer is formed as a two-dimensional array structure of minute convex bodies The size of each minute convex body in the phosphor layer is smaller than the beam spot size (beam spot diameter) of excitation light from the solid light source on the phosphor layer. Irradiation unevenness (color unevenness) such as a ring can be prevented.

  In particular, according to the invention of claim 2, in the light source device of claim 1, the light source device is of a transmissive type, and the phosphor layer is provided on a transparent substrate, and the phosphor layer and Between the transparent substrate, there is provided wavelength selection means having characteristics of transmitting excitation light from the solid light source and reflecting fluorescence from the phosphor layer. Can be further increased (the light intensity of the emitted light (illumination light) can be further increased). Further, between the phosphor layer and the transparent substrate, there is provided wavelength selection means having a characteristic of transmitting excitation light from the solid light source and reflecting fluorescence from the phosphor layer. The fluorescence can be prevented from propagating through the transparent substrate.

It is a figure which shows the conventional light source device. It is a figure which shows the light emission state of a fluorescent substance layer. It is a figure which shows the illuminating device which expands and projects the light source device of FIG. 1 on a predetermined projection surface using a lens system etc. 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 example of 1 structure of the light source device of this invention. It is a figure which shows the example of a manufacturing process of the fluorescent substance layer used for the light source device of FIG. 4, FIG. In the light source device of FIG. 4, FIG. 5, it is a figure which shows the optical path of the fluorescence from the fluorescent substance layer by the excitation light which injected into the fluorescent substance layer. It is a figure which shows the other structural example of the light source device of this invention. It is a figure which shows the other structural example of the light source device of this invention. It is a figure which shows the metal mold | die for producing the fluorescent substance layer of the light source device of FIG. 8, FIG. It is a figure which shows the example of preparation of the fluorescent substance layer of the light source device of FIG. 8, FIG. FIG. 10 is a diagram illustrating an optical path of fluorescence from the phosphor layer by excitation light incident on the phosphor layer in the light source device of FIGS. 8 and 9. It is a figure which shows the modification of the light source device of FIG. 4, FIG. It is a figure which shows an example of the illuminating device of this invention. It is a figure which shows the other structural example of the light source device of this invention.

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

  4, FIG. 5 (a), (b) is a figure which shows the example of 1 structure of the light source device of this invention. 4 is a schematic perspective view, FIG. 5 (a) is a schematic front view seen from the Y direction in FIG. 4, and FIG. 5 (b) is a schematic front view seen from the X direction in FIG. Referring to FIGS. 4, 5 (a), and (b), the light source device 10 includes a solid light source 5 that emits light having a predetermined wavelength in the visible light wavelength region as excitation light, and the solid light source 5. A phosphor layer 2 including at least one kind of phosphor that is excited by excitation light from the light source and emits fluorescence having a longer wavelength than the emission wavelength of the solid light source 5, and the solid light source 5 and the phosphor layer 2, Are spaced apart. In addition, illustration of the solid light source 5 is abbreviate | omitted in FIG. 5 (a), (b).

  Here, 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. However, when a light emitting diode is used, it is necessary to combine a lens system for condensing it as spot light on the phosphor layer 2.

Specifically, for example, a light emitting diode or a semiconductor laser that emits blue light having a light emission wavelength of about 460 nm using a GaN-based material can be used as the solid light source 5. In this case, as the phosphor of the phosphor layer 2, as the wavelength is excited by the blue light of about 440nm to about 470 nm, for example, the red ^{_{phosphor, CaAlSiN 3: Eu 2+, (}} Ca, Sr) AlSiN ₃ : Eu ²⁺ , Ca ₂ Si ₅ N ₈ : Eu ²⁺ , (Ca, Sr) ₂ Si ₅ N ₈ : Eu ²⁺ , KSiF ₆ : Mn ⁴⁺ , KTiF ₆ : Mn ^{4+ and the} like are used as the yellow phosphor. Y ₃ Al ₅ O ₁₂ : Ce ³⁺ , (Sr, Ba) ₂ SiO ₄ : Eu ²⁺ , Ca _x (Si, Al) ₁₂ (O, N) ₁₆ : Eu ^2+, etc. ^{_{, Lu 3 Al 5 O 12:}} Ce 3+, (Lu, Y) 3 Al 5 O 12: Ce 3+, Y 3 (Ga, Al) 5 O 12: Ce 3+, Ca 3 Sc 2 Si 3 O 12: _{^{e 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 2+ Etc. can be used.

Examples of the phosphor layer 2 include those obtained by dispersing these phosphor powders in glass or resin, glass phosphors obtained by adding a luminescent center ion to a glass matrix, phosphor ceramics that do not include a binding member such as a resin, and the like. Can be used. 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.

  The light source device 10 employs a method of extracting light such as fluorescence from the side opposite to the surface on which the excitation light of the phosphor layer 2 is incident (hereinafter referred to as a transmission method or a transmission type). In addition, by disposing the solid light source 5 and the phosphor layer 2 spatially apart from each other, it is possible to achieve a sufficiently high brightness as compared with the conventional case. More precisely, the transmission type or transmission type light source device is a phosphor when the phosphor layer 2 is irradiated with excitation light from the solid light source 5 as shown in FIGS. 5 (a) and 5 (b). Among the fluorescent components emitted from the layer 2, it is a light source device that uses a component that emerges on the opposite side of the solid light source 5. At this time, the transmitted component of the excitation light is also used, and the fluorescent component and the excitation light are used. The mixed light with the transmitted component can be taken out as outgoing light (illumination light).

  Further, as can be seen from FIGS. 5A and 5B, the size Dx and Dy of the entire phosphor layer 2 is generally the size of the beam spot of the excitation light from the solid light source 5 (beam spot diameter). It is larger than BM (Dx> BM, Dy> BM). In this case, as described above, the fluorescence is guided through the phosphor layer 2 toward the periphery of the phosphor layer 2, and irradiation unevenness such as a yellow ring is emitted to the emitted light (illumination light) from the phosphor layer 2. (Color unevenness) may occur.

  In order to prevent irradiation unevenness (color unevenness) such as yellow ring from occurring in the emitted light (illumination light) from the phosphor layer 2, in the present invention, the phosphor layer 2 is composed of a two-dimensional array structure of minute convex bodies 7. It is formed as.

  That is, in the present invention, since the phosphor layer 2 is formed as a two-dimensional array structure of the minute convex bodies 7, a space indicated by reference numeral 8 exists between the adjacent minute convex bodies 7. The presence of the space 8 prevents light from one minute convex body 7 from being guided to the adjacent minute convex body 7 (within the phosphor layer 2 around the phosphor layer 2). The light is prevented from being guided toward the light (the light guide path of the light guided through the phosphor layer 2 is blocked, and the light from one minute convex body 7 is forced to the outside of the phosphor layer 2. It is possible to prevent uneven emission (color unevenness) such as a yellow ring in the emitted light (illumination light) from the phosphor layer 2 in the entire phosphor layer 2.

  In addition, in the example of FIG. 4, FIG. 5 (a), (b), the shape of each micro convex body 7 of the fluorescent substance layer 2 is hemispherical shape. 4, 5 </ b> A, and 5 </ b> B, reference numeral 9 denotes a transparent substrate that supports the phosphor layer 2, and the phosphor layer 2 is provided on the transparent substrate 9.

  In addition, the sizes Ex and Ey of each minute convex body 7 of the phosphor layer 2 (Ex = Ey when each minute convex body 7 is hemispherical) are solid on the phosphor layer 2. The beam spot size (beam spot diameter) BM of the excitation light from the light source 5 is smaller (Ex ≦ BM, Ey ≦ BM).

  Specifically, the sizes Ex and Ey of each minute convex body 7 of the phosphor layer 2 (Ex = Ey when the shape of each minute convex body 7 is hemispherical) are 0.01-0. It is about 5 mm.

  The sizes Ex and Ey of the minute convex bodies 7 of the phosphor layer 2 are the beam spot size (beam spot diameter) BM (specifically, the excitation light from the solid light source 5 on the phosphor layer 2). (Ex.about.BM, Ey.ltoreq.BM), for example, so that the light guide path of the light guided through the individual micro-projections 7 does not extend over a wide range. In each of the minute convex bodies 7, it is possible to prevent irradiation unevenness (color unevenness) such as a yellow ring from occurring in the emitted light (illumination light) from each of the minute convex bodies 7.

  A method for producing the phosphor layer 2 formed as a two-dimensional array structure of the minute convex bodies 7 as shown in FIGS. 4, 5A, and 5B is, for example, FIGS. 6A to 6E. This is done as shown in

That is, as shown in FIG. 6 (a), a mold 11 having a micro-concave continuous gap 12 corresponding to the two-dimensional array structure (continuous structure) of the micro-projections 7 is prepared in advance. As shown in (b), Y ₃ Al ₅ O ₁₂ : Ce ³⁺ phosphor particles (yellow phosphor particles) dispersed in a silicone resin are filled in the voids 12 of the mold 11 and heated and cured to obtain fluorescence. The body block 13 is produced. Next, as shown in FIG. 6 (c), the phosphor block 13 is taken out from the mold 11, and as shown in FIG. 6 (d), the planar side of the phosphor block 13 taken out from the mold 11 is polished, The thickness t of the phosphor of the base portion 2a on which the minute convex body 7 is placed is set to 0.05 mm, for example. Finally, as shown in FIG. 6 (e), the polished phosphor layer 2 is attached to a transparent substrate 9 having a thickness of 1 mm, thereby forming a fluorescence formed as a two-dimensional array structure of minute convex bodies 7. The body layer (yellow phosphor layer) 2 can be produced.

  In the phosphor layer 2 actually manufactured by the above method, the diameter of the hemispherical bottom surface (Ex = Ey) of the hemispherical minute convex body 7 is 0.4 mm, and the hemispherical minuteness from the base portion 2a is 0.4 mm. The height Ez (= Ex / 2 = Ey / 2) of the convex body was 0.2 mm.

  The irradiation spot size BM of the excitation light from the solid light source (blue light emitting laser diode) 5 used at this time on the transparent substrate 9 is 1 mm in diameter, and on the transparent substrate 9 of each minute convex body 7. Is smaller than the irradiation spot area on the transparent substrate 9 of the excitation light from the solid-state light source 5 on the transparent substrate 9.

  A light source device that emits white light by actually combining the phosphor layer (yellow phosphor layer) 2 and the solid light source (blue light emitting laser diode) 5 produced as described above in the arrangement shown in FIG. 4 is produced. As a result, the occurrence of yellow ring could be suppressed. As shown in FIG. 7, this is because the excitation light (blue light) from the solid light source 5 incident on the phosphor layer 2 (the minute convex body 7) and the fluorescence from the phosphor layer 2 (yellow light). However, refraction occurs at the time of emission from the minute convex body 7 due to the space 8 between the adjacent minute convex bodies 7, and the propagation direction can be changed, so that the light does not enter the adjacent minute convex body (that is, This is considered to be because the light was emitted to the outside from a region having the same size as the irradiation spot of the excitation light from the solid light source 5 without propagating through the phosphor layer 2.

  Thus, in the present invention, the phosphor layer 2 is formed as a two-dimensional array structure of the minute convex bodies 7, and the size of each minute convex body 7 in the phosphor layer 2 is the same as that on the phosphor layer 2. It is possible to prevent the occurrence of uneven irradiation (color unevenness) such as a yellow ring by being smaller than the beam spot size (beam spot diameter) of the excitation light from the solid light source 5 in FIG.

  In the examples of FIGS. 4, 5A, and 5B, the shape of each minute convex body 7 of the phosphor layer 2 is a hemispherical shape. The shape of the body 7 can also be a shape such as a truncated pyramid, an elliptical hemisphere, a truncated truncated cone, a truncated triangular truncated cone, and a truncated hexagonal truncated cone.

  FIG. 8, FIG. 9A and FIG. 9B are diagrams showing another configuration example of the light source device of the present invention (the shape of each minute convex body 7 of the phosphor layer 2 is a truncated pyramid. FIG. 8 is a schematic perspective view, FIG. 9 (a) is a schematic front view seen from the Y direction of FIG. 8, FIG. 9 (b) is a schematic front view seen from the X direction of FIG. The portions corresponding to those in FIGS. 5A and 5B are denoted by the same reference numerals.

  The light source device 20 shown in FIGS. 8, 9A and 9B is similar to FIGS. 4 and 5 except that the shape of each minute convex body 7 of the phosphor layer 2 is a truncated pyramid. It is the same as the light source device 10 of a) and (b). That is, the solid light source 5 and the material of the phosphor layer 2 to be used are the same as those of the light source device 10 in FIGS. 4, 5A, and 5B.

  More specifically, even when the shape of each minute convex body 7 of the phosphor layer 2 is a truncated pyramid, the sizes Ex and Ey of each minute convex body 7 of the phosphor layer 2 are different from each other. The beam spot size (beam spot diameter) BM of the excitation light from the solid light source 5 on the body layer 2 is smaller (Ex ≦ BM, Ey ≦ BM).

  Specifically, even when the shape of each minute convex body 7 of the phosphor layer 2 is a truncated pyramid, the sizes Ex and Ey of each minute convex body 7 of the phosphor layer 2 are 0. .About 0.01 to 0.5 mm.

  The sizes Ex and Ey of the minute convex bodies 7 of the phosphor layer 2 are the beam spot size (beam spot diameter) BM (specifically, the excitation light from the solid light source 5 on the phosphor layer 2). (Ex.about.BM, Ey.ltoreq.BM), for example, so that the light guide path of the light guided through the individual micro-projections 7 does not extend over a wide range. In each of the minute convex bodies 7, it is possible to prevent irradiation unevenness (color unevenness) such as a yellow ring from occurring in the emitted light (illumination light) from each of the minute convex bodies 7.

  In the light source device 20 shown in FIGS. 8, 9A, and 9B, the method for producing the phosphor layer 2 is such that the shape of the gap 12 of the mold 11 corresponds to the truncated pyramid as shown in FIG. It can be manufactured in the same manner as shown in FIGS. FIG. 11 shows a phosphor layer (yellow phosphor layer) 2 produced by the mold 11 shown in FIG.

  In the actually produced phosphor layer (yellow phosphor layer) 2 of FIG. 11, the length (Ex = Ey) of one side of the bottom surface (square) of the minute convex body 7 which is a truncated pyramid is 0.2 mm. In addition, the height Ez of the minute convex body of the truncated pyramid from the base portion 2a of the phosphor layer 2 was 0.2 mm. Further, the thickness t of the base portion 2a of the phosphor layer 2 was 0.05 mm. In addition, the slope of the truncated pyramid has an angle of 10 degrees from the vertical plane.

  The irradiation spot size BM of the excitation light from the solid light source (blue light emitting laser diode) 5 used at this time on the transparent substrate 9 is 1 mm in diameter, and on the transparent substrate 9 of each minute convex body 7. Is smaller than the irradiation spot area on the transparent substrate 9 of the excitation light from the solid light source 5 on the transparent substrate 7.

  A light source device that emits white light by actually combining the phosphor layer (yellow phosphor layer) 2 and the solid light source (blue light emitting laser diode) 5 produced as described above in the arrangement shown in FIG. 8 is produced. As a result, the occurrence of yellow ring could be suppressed. This is because, as shown in FIG. 12, the excitation light (blue light) from the solid light source 5 that has entered the phosphor layer 2 (the minute convex body 7) and the fluorescence from the phosphor layer 2 (yellow light). However, refraction occurs at the time of emission from the minute convex body 7 due to the space 8 between the adjacent minute convex bodies 7, and the propagation direction can be changed, so that the incident light does not enter the adjacent minute convex body 7 (that is, This is considered to be because it can be taken out outside (without propagating through the phosphor layer 2). In addition, as shown by the left arrow in FIG. 12, the light emitted in the space 8 between the adjacent minute convex bodies 7 may go toward the adjacent minute convex body 7. Although the light enters the adjacent minute convex body 7 and propagates in the phosphor layer 2, the remaining light is reflected by the surface when it enters the adjacent minute convex body 7 and can be extracted outside. As a whole, it is considered that the light propagating in the phosphor layer 2 can be reduced and the occurrence of yellow ring can be suppressed.

  As described above, also in the light source device 20 of FIGS. 8, 9A, and 9B, the phosphor layer 2 is formed as a two-dimensional array structure of the minute convex bodies 7, and each of the phosphor layers 2 in the phosphor layer 2 is formed. The size of the minute convex body 7 is smaller than the beam spot size (beam spot diameter) of the excitation light from the solid-state light source 5 on the phosphor layer 2, thereby causing irradiation unevenness (color unevenness) such as yellow ring. ) Can be prevented.

  Further, in the light source device 10 shown in FIGS. 4, 5A and 5B (or the light source device 20 shown in FIGS. 8, 9A and 9B), as shown in FIG. 13 is a diagram corresponding to the light source device of FIGS. 4 and 5) (more precisely, between the phosphor layer 2 and the transparent substrate 9) between the phosphor layer 2 and the solid light source 5. In the meantime, wavelength selection means (wavelength selection filter (for example, dichroic mirror)) having characteristics of transmitting excitation light (for example, blue light) from the solid light source 5 and reflecting fluorescence (for example, yellow light) from the phosphor layer. 16 may be provided. Between the phosphor layer 2 and the solid light source 5, a wavelength selection unit having a characteristic of transmitting excitation light (eg, blue light) from the solid light source 5 and reflecting fluorescence (eg, yellow light) from the phosphor layer. When the wavelength selection filter (for example, dichroic mirror) 16 is provided, the fluorescence (for example, yellow light) from the phosphor layer is reflected to the side opposite to the solid light source 5, so that the light utilization efficiency is further improved. The light intensity of the emitted light (illumination light) can be further increased. That is, in the conventional configuration shown in FIG. 1, the use efficiency of light can be increased by using the wavelength selection means (wavelength selection filter), but irradiation unevenness (color unevenness) such as yellow ring occurs. End up. On the other hand, in the light source device of FIG. 13, the phosphor layer 2 is formed as a two-dimensional array structure of minute convex bodies 7, so that the wavelength selection means (wavelength selection filter) 16 is provided. Even when it is used, the light utilization efficiency can be further enhanced without causing uneven irradiation (color unevenness) such as yellow ring.

  Further, a wavelength having a characteristic of transmitting excitation light (for example, blue light) from the solid light source 5 and reflecting fluorescence (for example, yellow light) from the phosphor layer 2 between the phosphor layer 2 and the transparent substrate 9. When the selection means (wavelength selection filter (for example, dichroic mirror)) 16 is provided, it is possible to prevent fluorescence from propagating through the transparent substrate 9. That is, since the thickness of the base portion 2a of the phosphor layer 2 is as thin as about 0.05 mm, for example, it is considered that the amount of fluorescence propagating through the base portion 2a is very small. Therefore, there is fluorescence that propagates through the transparent substrate 9. For this fluorescence, as shown in FIG. 13, wavelength selection means (wavelength selection filter (for example, dichroic mirror)) that transmits blue light from the solid light source 5 and reflects yellow light that is fluorescence on the transparent substrate 9. By providing 16, it is possible to prevent fluorescence from entering the transparent substrate 9 and to prevent the fluorescence from propagating through the transparent substrate 9.

  The light source device 10 (or 20) can be configured as a lighting device by combining with a predetermined lens system, a mirror, a reflector, or the like. FIG. 14 is a view showing an illumination device in which the light source device 10 (or 20) and a lens system are combined. 14 includes a light source device 10 (or 20) and a lens system 52 that irradiates light from the light source device 10 (or 20) forward with a predetermined light distribution characteristic. And are stored. In this illuminating device, by using the light source device 10 (or 20), it is possible to obtain illumination light that does not cause color unevenness such as yellow ring even when the lens system 52 is used.

  In addition, the light source device 10 (or 20) of the above-described example is opposite to the surface of the phosphor layer 2 on which the excitation light is incident when the excitation light from the solid light source 5 is incident on the phosphor layer 2. However, the present invention is not limited to this, and the light source device is of a reflective type (reflective type) ( That is, the case of a reflection method (reflection type) in which light such as fluorescence is extracted from the same side as the surface on which the excitation light of the phosphor layer 2 is incident is also included in the scope of the present invention.

  FIG. 15 is a diagram showing an example of a light source device that is of a reflection type (reflection type). FIG. 15 is a diagram in the case where the configuration of the phosphor layer 2 is the same as that in FIGS. 4 and 5. In FIG. 15, the same parts as those in FIGS. doing. In the light source device of FIG. 15, light (fluorescence, excitation light) is reflected (light (fluorescence, excitation light) on the side opposite to the surface on which the excitation light (excitation light from the solid light source 5) of the phosphor layer 2 is incident. , Excitation light) is provided on the solid light source 5 side as outgoing light, and a substrate 45 having a reflective surface is provided. Here, as the substrate 45, the substrate 45 itself may be made of metal or, for example, a substrate in which a metal film is arranged on a transparent substrate can be used.

  Even when the light source device is configured as a reflection type (reflection type) as in the light source device of FIG. 15, the phosphor layer 2 is formed as a two-dimensional array structure of minute convex bodies 7, The size of each minute convex body 7 in the phosphor layer 2 is smaller than the beam spot size (beam spot diameter) of the excitation light from the solid light source 5 on the phosphor layer 2, so that a yellow ring or the like is obtained. Can be prevented from occurring.

  In addition, the illumination device as shown in FIG. 14 can be configured using a light source device of a reflection type (reflection type) as shown in FIG.

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

2 phosphor layer 5 solid light source 7 minute convex body 9 transparent substrate 10, 20 light source device 16 wavelength selection means (wavelength selection filter)
45 Substrate with Reflecting Surface 51 Case 52 Lens System

Claims (3)

A solid-state light source that emits light having a predetermined wavelength in the visible light wavelength region as excitation light, and at least one that emits fluorescence having a wavelength longer than the emission wavelength of the solid-state light source when excited by excitation light from the solid-state light source. A light source device comprising a phosphor layer containing a kind of phosphor,
The phosphor layer is formed as a two-dimensional array structure of minute convex bodies, and the size of each minute convex body in the phosphor layer is determined by the excitation light from the solid light source on the phosphor layer. A light source device characterized by being smaller than the size of a beam spot. 2. The light source device according to claim 1, wherein the light source device is of a transmissive type, the phosphor layer is provided on a transparent substrate, and the solid-state light source is disposed between the phosphor layer and the transparent substrate. A light source device comprising wavelength selection means having a characteristic of transmitting excitation light from and reflecting fluorescence from the phosphor layer. An illumination device using the light source device according to claim 1.

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