JP5611690B2 - Light source device, color adjustment method, lighting device - Google Patents

Description

  The present invention relates to a light source device, a color adjustment method, and a lighting device.

  A light source device in which a solid light source (photo semiconductor) such as an LED and a phosphor layer are combined is widely known as described in Patent Document 1, for example.

  FIG. 1 shows a light source device described in Patent Document 1. In this light source device, the phosphor layer 92 is generated in the phosphor layer 92 by directly bonding the phosphor layer 92 to an optical semiconductor (solid light source) 95 as shown in FIG. It is intended to dissipate the heat to the optical semiconductor (solid light source) 95 side.

JP 2006-005367 A

  However, in the light source device in which the optical semiconductor (solid light source) 95 and the phosphor layer 92 as shown in FIG. 1 are directly joined, the phosphor layer 92 excited by the excitation light from the optical semiconductor (solid light source) 95 is used. Of the light emitted from the light semiconductor (solid light source) 95 side and the light emitted from the light semiconductor (solid light source) 95 through the phosphor layer 92 without being absorbed by the phosphor layer 92. Excitation light is used. That is, the light source device of FIG. 1 is of a transmissive type that uses light transmitted through the phosphor layer 92.

  Here, when light emitted from the phosphor layer 92 is considered, there is also light reflected from the interface with the phosphor layer 92 together with the transmitted light and returning to the optical semiconductor (solid light source) 95 side, that is, reflected light. This light (reflected light) is re-absorbed by the optical semiconductor (solid light source) 95, so that there is a problem that the light cannot be used as illumination light.

  1 is intended to dissipate the heat of the phosphor layer 92 to the optical semiconductor (solid light source) 95 side, but the excitation light intensity of the optical semiconductor (solid light source) 95 is increased. Since heat is generated not only in the phosphor layer 92 but also in the optical semiconductor (solid light source) 95, the heat generated in the phosphor layer 92 is dissipated from the side of the optical semiconductor (solid light source) 95 that is also generating heat. There was a problem that the efficiency of was not good.

  As described above, the light source device shown in FIG. 1 has a limitation on high luminance because it is of a transmissive type and the efficiency of heat dissipation with respect to the heat generation of the phosphor layer 92 is not good.

  Such a light source device combining a solid-state light source (photo semiconductor) and a phosphor layer increases its application range to general lighting and automobile headlamps by increasing the brightness, and further spreads in various uses. It is thought to go forward.

  In order to increase the luminance of the light source device, the applicant of the present invention has a space between the solid light source 5 and the phosphor layer 2 as described in the prior application (Japanese Patent Application No. 2009-286397) of the present application (as shown in FIG. 2). The light source device 10 is proposed in which the excitation light from the solid-state light source 5 is incident on the phosphor layer 2 and the fluorescence and excitation light from the phosphor layer 2 are extracted in a reflective manner. Here, the reflection method is a method in which fluorescence and excitation light are extracted using reflection by a reflection surface provided on the opposite side of the surface of the phosphor layer 2 from the surface on which excitation light is incident. By adopting the reflection method, the reflected light of the fluorescence and the reflected light of the excitation light can be used with little optical loss, so that high brightness can be achieved. In FIG. 1, reference numeral 6 denotes a heat dissipation substrate, and reference numeral 7 denotes a joint portion between the phosphor layer 2 and the heat dissipation substrate 6.

  However, in the reflection-type light source device 10 in which the solid light source 5 and the phosphor layer 2 are spatially separated from each other, two components having different angular dependencies of emission intensity are reflected in the reflected light of the excitation light reflected by the phosphor layer 2. Therefore, there is a problem that not all reflection components can be used effectively. Referring to FIG. 3, when the solid light source 5 that emits excitation light with strong directivity such as a semiconductor laser is used and the excitation light from the solid light source 5 is irradiated onto the phosphor layer 2, the angle is A diffuse reflection component having no dependency and a regular reflection component having strong directivity in the direction of the reflection angle are generated. Among them, the diffuse reflection component of the excitation light having no angle dependency is emitted in the light extraction direction (direction perpendicular to the surface of the phosphor layer 2) together with the fluorescence emitted by the phosphor layer having no angle dependency ( Hereinafter, in the present application, for convenience of explanation, light that is emitted around and used in the light extraction direction is referred to as illumination light), and can be used as illumination light, but is a regular reflection component that has a strong angle dependency. Is emitted in a direction significantly different from the light extraction direction (note that the specular reflection component having a strong angle dependency is emitted in a direction different from the light extraction direction, particularly in the reflection method, from the solid light source 5. By making light incident on the phosphor layer 2 obliquely), it could not be used as illumination light. For this reason, there is a limit to further increasing the brightness.

  It is an object of the present invention to provide a light source device, a color adjustment method, and a lighting device that can further increase the brightness.

In order to achieve the above object, the invention according to claim 1 is a solid light source that emits light having a predetermined wavelength in a wavelength region from ultraviolet light to visible light as excitation light, and excitation light from the solid light source. And a phosphor layer containing at least one kind of phosphor that emits fluorescence having a wavelength longer than the emission wavelength of the solid light source, and the solid light source and the phosphor layer are arranged spatially separated from each other A light source device that extracts at least fluorescence from a predetermined surface of the phosphor layer, and includes a reflection member that directly reflects the specular component of excitation light reflected by the phosphor layer toward the phosphor layer. It is characterized by that.

The invention described in claim 2 is a solid-state 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-state light source when excited by excitation light from the solid-state light source. A solid-state light source, the phosphor layer being spatially spaced apart, and a light source device that extracts at least fluorescence from a predetermined surface of the phosphor layer. A light diffusing layer disposed adjacent to the phosphor layer, and a reflective member that directly reflects a specular reflection component of excitation light reflected by the phosphor layer toward the light diffusing layer and / or the phosphor layer; And a reflection angle adjusting means for adjusting the reflection angle of the reflecting member.

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 light source device that includes at least a fluorescent light from a predetermined surface of the phosphor layer, the solid light source and the phosphor layer being spatially spaced apart from each other, The color adjusting method according to claim 1, wherein a light diffusing layer is arranged adjacent to the phosphor layer, and a regular reflection component of excitation light reflected by the phosphor layer is reflected by the reflecting member on the light diffusing layer and / or the phosphor. The color of the illumination light is adjusted by directly reflecting the light toward the layer and adjusting the reflection angle of the reflecting member to change the ratio of the irradiation area of the regular reflection component of the excitation light to the phosphor layer and the diffusion layer. It is characterized by that.

  According to a fourth aspect of the present invention, there is provided a lighting device using the light source device according to any one of the first to second aspects.

  According to the first and fourth aspects of the present invention, a solid-state light source that emits light having a predetermined wavelength in a wavelength region from ultraviolet light to visible light as excitation light, and excitation by the excitation light from the solid-state light source And a phosphor layer containing at least one phosphor that emits fluorescence having a longer wavelength than the emission wavelength of the solid light source, and the solid light source and the phosphor layer are spatially separated from each other. A light source device that extracts at least fluorescence from a predetermined surface of the phosphor layer, and includes a reflecting member that reflects a regular reflection component of excitation light reflected by the phosphor layer toward the phosphor layer. Therefore, the utilization efficiency of the regular reflection component of the excitation light can be increased, and the brightness can be further increased.

  According to the invention of claim 2, claim 3, and claim 4, the solid light source that emits visible light as excitation light, and the emission wavelength of the solid light source that is excited by the excitation light from the solid light source. A phosphor layer containing at least one type of phosphor that emits long-wavelength fluorescence, wherein the solid-state light source and the phosphor layer are spatially separated from each other, and a predetermined surface of the phosphor layer A light source device for extracting at least fluorescence from the phosphor layer, wherein a light diffusion layer is disposed adjacent to the phosphor layer, and the regular reflection component of the excitation light reflected by the phosphor layer is used as the light diffusion layer and / or the phosphor. Since the reflection member that reflects toward the layer and the reflection angle adjustment means that adjusts the reflection angle of the reflection member are provided, the utilization efficiency of the regular reflection component of the excitation light is improved, and the brightness is further increased. It becomes possible and adjusts the color of the illumination light , It is possible to suppress the color unevenness of the illumination light.

It is a figure which shows the conventional light source device. It is a figure which shows the light source device as described in the prior application of this application. In the reflection-type light source device in which the solid light source and the phosphor layer are spatially separated, the reflected light of the excitation light reflected by the phosphor layer has two components having different angle dependencies of emission intensity. FIG. It is a figure which shows the example of 1 structure of the light source device of the 1st Embodiment of this invention. It is a figure which shows the structural example on which the several fluorescent substance layer which consists of a mutually different fluorescent substance was laminated | stacked. It is a figure which shows the example comprised as a reflection type fluorescence rotary body which rotates a fluorescent substance layer around a rotating shaft. It is a figure which shows the structural example about the fluorescent substance layer of a reflection type fluorescent rotating body. It is a figure which shows the other structural example about the fluorescent substance layer of a reflection type fluorescent rotator. It is a figure which shows the other structural example about the fluorescent substance layer of a reflection type fluorescent rotator. It is a figure which shows the example of 1 structure of the light source device of the 2nd Embodiment of this invention. It is a figure which shows a mode that the regular reflection component of excitation light is reflected with a reflection member, and is irradiated to the direction of a light-diffusion layer. It is a figure which shows a mode that the regular reflection component of excitation light is reflected with a reflecting member, and is irradiated to the direction of a fluorescent substance layer and a light-diffusion layer. It is a figure which shows a mode that the regular reflection component of excitation light is reflected by a reflection member, and is irradiated to the direction of a fluorescent substance layer. It is a figure which shows the structural example on which the several fluorescent substance layer which consists of a mutually different fluorescent substance was laminated | stacked. It is a figure which shows the other structural example of the light source device of the 2nd Embodiment of this invention. It is a figure which shows the example comprised as a reflection type fluorescence rotary body which rotates a fluorescent substance layer and a light-diffusion layer around the rotating shaft. It is a figure which shows the other structural example about the fluorescent substance layer of a reflection type fluorescent rotator. It is a figure which shows the other structural example about the fluorescent substance layer of a reflection type fluorescent rotator. It is a figure which shows the other structural example about the fluorescent substance layer of a reflection type fluorescent rotator. It is a figure which shows the illuminating device which provided the predetermined lens system in the light extraction direction of the light source device of 1st Embodiment. It is a figure which shows the illuminating device which provided the predetermined lens system in the light extraction direction of the light source device of 2nd Embodiment.

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

(First embodiment)
FIGS. 4A and 4B are diagrams showing a configuration example of the light source device according to the first embodiment of the present invention. 4A is a front view of the whole, FIG. 4B is a plan view of a portion where the phosphor layer is provided, and FIGS. 4A and 4B are the same as FIG. The same code | symbol is attached | subjected to the location. Referring to FIGS. 4A and 4B, the light source device 20 includes a solid-state light source 5 that emits light of a predetermined wavelength in a wavelength region from ultraviolet light to visible light, A phosphor layer 2 including at least one kind of phosphor that is excited by excitation light and emits fluorescence having a wavelength longer than that of the solid light source 5, and the solid light source 5 and the phosphor layer 2 are spatially separated. Are located apart.

  Here, the phosphor layer 2 is substantially free of a resin component.

  In addition, a heat dissipation substrate 6 is provided on the surface of the phosphor layer 2 opposite to the surface on which the excitation light is incident, and the phosphor layer 2 is bonded to the heat dissipation substrate 6 by the joint portion 7. Yes. Here, as described later, a material having a high thermal conductivity is preferably used for the joint portion 7.

  Further, in the light source device 20, similarly to the light source device 10 shown in FIG. 2, the reflection provided on the opposite side of the surface of the phosphor layer 2 from the surface on which the excitation light from the solid light source 5 is incident. A method of taking out light such as fluorescence by using reflection by a surface (hereinafter referred to as a reflection method) is employed.

  As described above, the light source device 20 basically has the solid light source 5 and the phosphor layer 2 arranged spatially separated in the same manner as the light source device 10 shown in FIG. It is characterized by use.

  That is, as in the conventional light source device shown in FIG. 1, when the phosphor layer 92 is in contact with the solid light source 95, both the phosphor layer 92 and the solid light source 95 are used even if the luminance is increased. Since both of them are heated, the efficiency of heat dissipation from the phosphor layer 92 is poor. However, in the light source device 20 of FIGS. 4A and 4B, the fluorescence is the same as the light source device 10 shown in FIG. By disposing the body layer 2 away from the solid-state light source 5, it is possible to dissipate heat from the phosphor layer 2 to the low-temperature heat dissipation substrate 6 through the joint 7 even when the luminance is increased. Thus, the efficiency of heat dissipation from the phosphor layer 2 can be remarkably increased as compared with the conventional light source device shown in FIG.

  Further, in the conventional light source device shown in FIG. 1, among the excitation light from the solid light source 95 and the fluorescence from the phosphor layer 92, the fluorescence emitted to the side opposite to the solid light source 95 and the phosphor layer 92 Excitation light from a solid light source 95 that is transmitted without being absorbed is used. In other words, the transmission method is used. Here, in the transmission method, when the emitted light from the phosphor layer 92 is considered, the excitation light is reflected at the interface with the phosphor layer 92 together with the transmitted light and returns to the solid light source 95 side, that is, reflected. There is also light, and this reflected light is reabsorbed by the solid light source 95 and becomes light that cannot be used as illumination light. Further, since the fluorescence from the phosphor layer 92 is emitted from both sides of the phosphor layer 92, the light emitted to the solid light source 95 side cannot be used. Thus, in the transmission method, the light use efficiency is reduced. In addition, in the transmission method, in order to obtain illumination light with a desired chromaticity, it is necessary to increase the thickness of the phosphor layer 92, and the distance from the phosphor layer 92 to the solid light source 95 becomes long. It was disadvantageous in dissipating the heat from 92 to the solid light source 95.

  On the other hand, in the light source device 20 shown in FIGS. 4A and 4B, the light (excitation light, fluorescence) emitted to the side opposite to the solid light source 5 is reflected on the reflective surface (for example, the reflective surface of the substrate). Since the reflection method that reflects to the side 5 is adopted, the light emission (fluorescence) from the phosphor layer 2 excited by the excitation light from the solid light source 5 (ie, fluorescence) (ie, the light source device 10 shown in FIG. 2) Fluorescence emitted to the solid light source 5 side), excitation light from the solid light source 5 that was not absorbed by the phosphor layer 2 (that is, reflected light of light from the solid light source 5 that was not absorbed by the phosphor layer 2), and Can be used as illumination light with little light loss, so that high brightness can be achieved. In contrast to the transmission type, in the reflection type, even if the thickness of the phosphor layer 2 is less than half, the optical path lengths in the phosphor layer 2 are equal, and light of the same chromaticity can be obtained. In addition, the distance from the phosphor layer 2 to the substrate 6 is shortened, which is advantageous in terms of heat dissipation.

  As described above, in the light source device 20 shown in FIGS. 4A and 4B, basically, the solid light source 5 and the phosphor layer 2 are spatially separated as in the light source device 10 shown in FIG. And using the light emission in a reflective manner, it is possible to achieve higher brightness than in the past.

  Further, in the light source device 20 shown in FIGS. 4A and 4B, since the phosphor layer 2 that does not substantially contain a resin component is used, there is no discoloration due to heat and light absorption is small. For this reason, it is possible to further increase the luminance.

  Here, the phosphor layer 2 substantially not containing a resin component means that the resin component normally used for forming the phosphor layer is 5 wt% or less of the phosphor layer. As a material for realizing such a phosphor layer, 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, or a phosphor polycrystal (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 layer mentioned here does not substantially contain a resin component and is composed only of an inorganic substance, discoloration due to heat does not occur. 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 layer 2 to the substrate 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 layer 2.

  The phosphor layer 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 ultraviolet light, the phosphor layer 2 includes at least one kind of phosphor among phosphors such as blue, green, and red. When the solid light source 5 emits ultraviolet light, the phosphor layer 2 contains, for example, blue, green, and red phosphors (the blue, green, and red phosphors are, for example, uniformly When the phosphor layer 2 is irradiated with ultraviolet light from the solid light source 5, white illumination light can be obtained as reflected light. Moreover, when the solid light source 5 emits blue light as visible light, the phosphor layer 2 includes at least one kind of phosphor among phosphors such as green, red, and yellow. When the solid-state light source 5 emits blue light as visible light, when the phosphor layer 2 contains, for example, green and red phosphors (the green and red phosphors are dispersed uniformly, for example) When the phosphor layer 2 is irradiated with blue light from the solid light source 5, illumination light such as white can be obtained as reflected light. Further, when the solid light source 5 emits blue light as visible light, for example, when the phosphor layer 2 contains only a yellow phosphor, the blue light from the solid light source 5 is emitted from the phosphor layer 2. When illuminating, illumination light such as white can be obtained as reflected light.

  Further, in the light source device 20 of FIGS. 4A and 4B, the heat dissipation substrate 6 includes light (luminescence (fluorescence) from the phosphor layer 2 excited by excitation light from the solid light source 5), and the phosphor layer. The role of the reflecting surface for the light from the solid light source 5 that has not been absorbed in 2), the role of dissipating the heat dissipated from the phosphor layer 2 to the outside, and the role of the support substrate of the phosphor layer 2 is there. For this reason, high light reflection characteristics, heat transfer characteristics, and workability are required. The heat dissipation substrate 6 can be a metal substrate, oxide ceramics such as alumina, non-oxide ceramics such as aluminum nitride, etc., but a metal substrate having particularly high light reflection characteristics, heat transfer characteristics, and workability is used. It is desirable to be done.

  In addition, an organic adhesive, an inorganic adhesive, low-melting glass, metal (metal brazing), or the like can be used for the joint 7 between the phosphor layer 2 and the heat dissipation substrate 6. The junction 7 also has a reflection surface for light (light emission (fluorescence) from the phosphor layer 2 excited by excitation light from the solid light source 5 and light from the solid light source 5 not absorbed by the phosphor layer 2). Since it plays a role and a role to dissipate heat from the phosphor layer, it is desirable to use a metal (metal brazing) having both high light reflection characteristics and heat transfer characteristics. Alternatively, a conductive adhesive containing a metal component can be used for the joint 7 between the phosphor layer 2 and the heat dissipation substrate 6.

  By the way, as described above, when the phosphor layer 2 is irradiated with excitation light from the solid light source 5, a diffuse reflection component having no angle dependency and a regular reflection component having strong directivity in the direction of the reflection angle are generated. The specular reflection component with strong directivity (strong angle dependency) is emitted in a direction significantly different from the light extraction direction (illumination light extraction direction). The light is emitted in a direction different from the light extraction direction (illumination light extraction direction), particularly in the reflection method, by exciting light from the solid light source 5 incident on the phosphor layer 2 obliquely) It could not be used, and there was a limit to further increasing the brightness.

  In the light source device 20 of FIGS. 4A and 4B, the reflection that reflects the regular reflection component of the excitation light reflected by the phosphor layer 2 toward the phosphor layer 2 in order to further increase the luminance. A member 3 is provided.

  Here, it is desirable to use a reflective member 3 having a reflectance of 95% or more, particularly 99% or more, with respect to excitation light. This is because when the reflectance is low, the reflection member 3 may be heated and burnt when the excitation light intensity is high. Further, it is desirable that the reflection member 3 has a small diffuse reflection component. This is to efficiently irradiate the phosphor layer 2 with the regular reflection component of the excitation light.

  As described above, the light source device 20 in FIGS. 4A and 4B is further provided with the reflecting member 3 that reflects the regular reflection component of the excitation light reflected by the phosphor layer 2 toward the phosphor layer 2. As a result, the utilization efficiency of the excitation light (the regular reflection component of the excitation light) can be further increased, and the brightness can be further increased.

  4A and 4B, only one phosphor layer 2 is provided. For example, as shown in FIG. 5, a plurality of phosphor layers ( In the example of FIG. 5, a configuration in which two phosphor layers 2j and 2k) are laminated may be employed. In this case, for example, when the solid light source 5 emits blue light as visible light, the phosphor layer 2j is made of a green phosphor, and the phosphor layer 2k is a red phosphor. If it is used, illumination light such as white can be obtained as reflected light.

  Further, in the light source device 20 of FIGS. 4A and 4B, the phosphor layer 2 may be fixed, but the phosphor layer 2 may be configured to be movable. For example, as shown in FIG. 6, it can also be configured as a reflection type fluorescent rotating body 1 in which the fluorescent layer 2 is rotated around a rotation axis X (rotated by a motor 4 or the like). That is, the reflection type fluorescent rotator 1 can be realized by connecting the phosphor layer 2 and the heat dissipation substrate 6 joined to the motor 4 or the like. In the reflection type fluorescent rotating body 1, the heat dissipation substrate 6 and the joint 7 function as a reflection surface for excitation light and fluorescence. In addition, the shape of the heat dissipation substrate 6 may be a disk shape or a quadrangle. In addition, in order to ensure the stability of rotation, it is possible to cut out a part of the disk or to have a shape with a weight on the contrary.

  In the example of FIG. 6, only one type of phosphor layer is used as the phosphor layer 2 of the reflective phosphor rotator 1. Specifically, in the example of FIG. 6, only the phosphor layer made of, for example, a yellow phosphor is used as the phosphor layer 2 of the reflective phosphor rotator 1, and in this case, the solid light source 5 emits blue light. If it is used, illumination lights, such as white, can be obtained as reflected light. Alternatively, in the example of FIG. 6, as the phosphor layer 2 of the reflective phosphor rotator 1, for example, a phosphor layer in which, for example, blue, green, and red phosphors are uniformly dispersed and mixed, for example. In this case, if a solid-state light source that emits ultraviolet light is used, illumination light such as white can be obtained as reflected light. However, the present invention is not limited to this, and various modifications are possible. That is, the phosphor layer 2 of the reflection type fluorescent rotator 1 can be configured such that at least one phosphor layer of blue, green, yellow, red, or the like is disposed. 7A, 7B, 8A, and 8B show configuration examples of the phosphor layer 2 of the reflection type fluorescent rotator 1. FIG. 7 (a) and 8 (a) are plan views, respectively, and FIGS. 7 (b) and 8 (b) are respectively along the line AA in FIGS. 7 (a) and 8 (a). It is sectional drawing. The example of FIGS. 7A and 7B is a case where only one type of phosphor layer (for example, a phosphor layer made of a yellow phosphor) is used as the phosphor layer 2, and the example of FIG. It corresponds. 8 (a) and 8 (b) show three types of phosphor layers 2a, 2b, and 2c (for example, a red phosphor composed of a red phosphor) as the phosphor layer 2 of the reflection type fluorescent rotator 1. The green phosphor layer 2b composed of the layer 2a, the green phosphor, and the blue phosphor layer 2c) composed of the blue phosphor are provided as phosphor regions divided into three equal parts. In this case, the solid light source 5 If a material that emits ultraviolet light is used, illumination light such as white can be obtained as reflected light when the reflective fluorescent rotating body 1 is rotated. In addition, various modifications are possible.

  For example, in the above-described example of the reflective fluorescent rotator 1, when a plurality of phosphor layers are used, the phosphor layers are arranged in the horizontal direction as shown in FIGS. 8 (a) and 8 (b). 9 (a) and 9 (b), a plurality of phosphor layers (in the example of FIGS. 9 (a) and 9 (b), two phosphor layers 2j and 2k) are stacked in the vertical direction ( It may be arranged). 9A is a plan view, and FIG. 9B is a cross-sectional view taken along the line AA in FIG. 9A. In this case, for example, when the solid light source 5 emits blue light as visible light, the phosphor layer 2j is made of a green phosphor, and the phosphor layer 2k is made of a red phosphor. If a thing is used, illumination lights, such as white, can be obtained as reflected light.

  In this way, by configuring the phosphor layer 2 as the reflection-type phosphor rotator 1 that rotates around the rotation axis X (rotates by the motor 4 or the like), that is, the phosphor layer 2 is formed with respect to the solid light source 5. By rotating, it is possible to disperse the places where the excitation light from the solid light source 5 hits, and to suppress the heat generation in the light irradiating part (using the fluorescent rotating body 1 can suppress the heat generation of the fluorescent substance in the first place). This makes it possible to further increase the brightness.

  In the examples of FIGS. 5, 6, 7 (a), 7 (b), 8 (a), 8 (b), 9 (a) and 9 (b) described above, the phosphor layer 2; 2 j, 2k; By providing the reflecting member 3 that reflects the specular reflection component of the excitation light reflected by 2a, 2b, and 2c toward the phosphor layer 2, the utilization efficiency of the excitation light (the specular reflection component of the excitation light) is further increased. It is possible to increase the brightness further.

(Second Embodiment)
FIGS. 10A and 10B are diagrams showing a configuration example of the light source device according to the second embodiment of the present invention. 10 (a) is a front view of the whole, FIG. 10 (b) is a plan view of a portion where a phosphor layer is provided, and FIGS. 10 (a) and 10 (b) are the same as FIG. , (B) are denoted by the same reference numerals. Referring to FIGS. 10A and 10B, the light source device 30 includes a solid light source 5 that emits visible light (for example, blue light) as excitation light, and the solid light source that is excited by the excitation light from the solid light source 5. A phosphor layer 2 containing at least one kind of phosphor that emits fluorescence having a wavelength longer than the emission wavelength of the light source 5, and the solid light source 5 and the phosphor layer 2 are arranged spatially apart from each other. A light source device that extracts at least fluorescence from a predetermined surface of the phosphor layer 2, a light diffusion layer 9 is disposed adjacent to the phosphor layer 2, and a regular reflection component of excitation light reflected by the phosphor layer 2 is emitted as light. A reflection member 3 that reflects toward the diffusion layer 9 and / or the phosphor layer 2 and a reflection angle adjusting means 22 that adjusts the reflection angle of the reflection member 3 are provided.

  Here, when the regular reflection component of the excitation light reflected by the phosphor layer 2 is incident on the light diffusion layer 9 due to reflection by the reflection member 3, the light diffusion layer 9 has a regular reflection component (strong angle). Specular reflection component with dependency) is converted into diffuse reflection light without angle dependency, and this diffuse reflection light is also used as part of the excitation light component of illumination light (fluorescence, excitation light) Is provided.

  More specifically, in the second embodiment, the utilization efficiency of the excitation light (the regular reflection component of the excitation light) is further increased, and the ratio of the fluorescence component and the excitation light component contained in the illumination light (fluorescence, excitation light) is further increased. It is intended to adjust the intensity ratio of the fluorescent component and the excitation light component to suppress the color variation of the illumination light. Here, the color variation is generated when the intensity ratio of the excitation light component and the fluorescence component included in the illumination light is deviated from an ideal value due to initial variation described later, variation during driving, or the like.

  Specifically, in a light source device using a solid light source and a phosphor layer, there is a variation in illumination light color due to a variation in the emission wavelength of the solid light source and the film thickness of the phosphor layer, which is a typical example of a solid light source. Even if diodes and laser diodes are produced from the same wafer due to the non-uniform composition of the light emitting layer, the emission wavelength varies by about 5 nm (hereinafter referred to as initial variation). In addition to this, it is known that when the ambient temperature changes, the emission wavelength also changes by about 5 nm (hereinafter referred to as variation during driving). Although the thickness of the phosphor ceramics can be precisely controlled by polishing, the initial variation in the emission wavelength of the solid light source can be suppressed by selecting the phosphor ceramics with the optimum thickness. Could not be suppressed. Further, the selection of the phosphor ceramics for suppressing the initial variation is not desirable because it requires a large amount of phosphor ceramics in stock and the number of man-hours for the selection, which increases the cost. Therefore, a method for suppressing both the initial variation of illumination light and the variation during driving is desired.

  The inventor of the present application has repeatedly studied to suppress the color variation as described above in the reflective illumination device in which the solid light source 5 and the phosphor layer 2 are spatially separated, and as a solution therefor, We focused on the specular reflection component of the excitation light, which had a strong angular dependence that could not be used. That is, the regular reflection component of the excitation light (the regular reflection component of the excitation light reflected by the phosphor layer) is reflected by the reflection member 3 toward the light diffusion layer 9 and / or the phosphor layer 2, and By adjusting the reflection angle in the direction indicated by the arrow Y in FIG. 10A by the reflection angle adjusting means 22 and changing the irradiation area ratio of the regular reflection component of the excitation light to the phosphor layer 2 and the diffusion layer 9, It has been found that the color of the illumination light can be adjusted to suppress the color variation of the illumination light.

  As a specific example, for example, when the excitation light component is insufficient, the excitation light component may be supplemented, and the regular reflection component of the excitation light that has not been used so far is used as the supplemented excitation light component. That is, the regular reflection component of the excitation light is reflected by the reflecting member 3 as shown in FIGS. 11A and 11B and irradiated in the direction of the light diffusion layer 9 disposed adjacent to the phosphor layer 2. Thus, the specular reflection component having a strong angle dependency can be made a diffuse reflection light having no angle dependency, and the diffuse reflection light from the light diffusion layer 9 is converted into the fluorescence component from the phosphor layer 2 and the phosphor layer 2. It can be used as illumination light together with the diffuse reflection component of the excitation light generated in the above, and it is possible to supplement the excitation light component in the illumination light and suppress the color variation of the illumination light. 11A is a front view of the whole, and FIG. 11B is a plan view of a portion where the phosphor layer 2 and the light diffusion layer 9 are provided.

  Further, by changing the angle of the reflecting member 3 in the direction indicated by the arrow Y by the reflection angle adjusting means 22, FIGS. 11 (a), 11 (b), 12 (a), 12 (b), 13 (a), As shown in (b), the irradiation area ratio of the phosphor layer 2 and the light diffusion layer 9 of the regular reflection component of the excitation light can be changed. 12 (a) and 13 (a) are front views of the whole, and FIGS. 12 (b) and 13 (b) are plan views of portions where the phosphor layer 2 and the light diffusion layer 9 are provided. FIG. For example, when it is desired to increase the amount of excitation light in the illumination light, the irradiation area to the light diffusion layer is increased as shown in FIGS. 11A and 11B, and for example, the amount of fluorescence in the illumination light is increased. If desired, as shown in FIGS. 12 (a), 12 (b), 13 (a) and 13 (b), the irradiation area ratio of the regular reflection component of the excitation light to the phosphor layer 2 with respect to the light diffusion layer 9 is set. By increasing the amount, the amount of fluorescent light in the illumination light can be increased. As described above, in the light source device 30 in FIGS. 10A and 10B, the excitation light component included in the illumination light is changed by changing the angle of the reflecting member 3 in the direction indicated by the arrow Y by the reflection angle adjusting unit 22. Since the ratio to the fluorescent component can be continuously adjusted, it is possible to suppress color variation during driving.

  In other words, in the second embodiment of the present invention, the solid light source 5 that emits visible light (for example, blue light) as excitation light, and the emission wavelength of the solid light source 5 that is excited by the excitation light from the solid light source 5. A phosphor layer 2 including at least one kind of phosphor that emits fluorescence having a longer wavelength, and the solid-state light source 5 and the phosphor layer 2 are spatially separated from each other, and the phosphor A color adjustment method in a light source device that extracts at least fluorescence as illumination light from a predetermined surface of the layer 2, wherein a light diffusion layer 9 is arranged adjacent to the phosphor layer 2 and reflected by the phosphor layer 2. A regular reflection component of light is reflected by the reflection member 3 toward the light diffusion layer 9 and / or the phosphor layer 2, and a reflection layer of the excitation light is adjusted by adjusting a reflection angle of the reflection layer 3. 2 and change the irradiation area ratio to the diffusion layer 9 And in, by adjusting the color of the illumination light, the color variations of illuminating light, the color variation at the time of driving can be suppressed.

  In the second embodiment, as in the first embodiment, the phosphor layer 2 that does not substantially contain a resin component is used.

  In addition, a heat dissipation substrate 6 is provided on the surface of the phosphor layer 2 opposite to the surface on which the excitation light is incident, and the phosphor layer 2 is bonded to the heat dissipation substrate 6 by the joint portion 7. Yes. Here, as described later, a material having a high thermal conductivity is preferably used for the joint portion 7. A light diffusion layer 9 is also provided on the heat dissipation substrate 6.

  Further, in the light source device 30, as in the light source device 20 in FIGS. 4A and 4B, the surface of the phosphor layer 2 opposite to the surface on which the excitation light from the solid light source 5 is incident. A method of taking out light such as fluorescent light using reflection by a reflecting surface provided in (hereinafter referred to as a reflection method) is employed.

  Thus, this light source device 30 basically arranges the solid light source 5 and the phosphor layer 2 apart from each other in the same manner as the light source device 20 of FIGS. 4 (a) and 4 (b). It is characterized by using light emission in a reflective manner.

  That is, as in the conventional light source device shown in FIG. 1, when the phosphor layer 92 is in contact with the solid light source 95, both the phosphor layer 92 and the solid light source 95 are used even if the luminance is increased. Since both of them are heated, the efficiency of heat dissipation from the phosphor layer 92 is poor. However, in the light source device 30 in FIGS. 10A and 10B, the light source device 20 in FIGS. 4A and 4B. Similarly to the above, when the phosphor layer 2 is arranged away from the solid light source 5 to increase the brightness, the heat from the phosphor layer 2 is transferred to the low-temperature heat dissipation substrate 6 via the joint 7. It becomes possible to dissipate, and the efficiency of heat dissipation from the phosphor layer 2 can be significantly increased as compared with the conventional light source device shown in FIG.

  Further, in the conventional light source device shown in FIG. 1, among the excitation light from the solid light source 95 and the fluorescence from the phosphor layer 92, the fluorescence emitted to the side opposite to the solid light source 95 and the phosphor layer 92 Excitation light from a solid light source 95 that is transmitted without being absorbed is used. In other words, the transmission method is used. Here, in the transmission method, when the emitted light from the phosphor layer 92 is considered, the excitation light is reflected at the interface with the phosphor layer 92 together with the transmitted light and returns to the solid light source 95 side, that is, reflected. There is also light, and this reflected light is reabsorbed by the solid light source 95 and becomes light that cannot be used as illumination light. Further, since the fluorescence from the phosphor layer 92 is emitted from both sides of the phosphor layer 92, the light emitted to the solid light source 95 side cannot be used. Thus, in the transmission method, the light use efficiency is reduced. In addition, in the transmission method, in order to obtain illumination light with a desired chromaticity, it is necessary to increase the thickness of the phosphor layer 92, and the distance from the phosphor layer 92 to the solid light source 95 becomes long. It was disadvantageous in dissipating the heat from 92 to the solid light source 95.

  On the other hand, in the light source device 30 of FIGS. 10A and 10B, the light (excitation light, fluorescence) emitted to the side opposite to the solid light source 5 is reflected on the reflective surface (for example, the reflective surface of the substrate). Since the reflection method reflecting to the 5 side is adopted, the light emission from the phosphor layer 2 excited by the excitation light from the solid light source 5 (similar to the light source device 20 of FIGS. 4A and 4B) Fluorescence) (that is, fluorescence emitted to the solid light source 5 side) and excitation light from the solid light source 5 that is not absorbed by the phosphor layer 2 (that is, light from the solid light source 5 that is not absorbed by the phosphor layer 2). Can be used as illumination light with little light loss, so that high brightness can be achieved. In contrast to the transmission type, in the reflection type, even if the thickness of the phosphor layer 2 is less than half, the optical path lengths in the phosphor layer 2 are equal, and light of the same chromaticity can be obtained. In addition, the distance from the phosphor layer 2 to the substrate 6 is shortened, which is advantageous in terms of heat dissipation.

  As described above, in the light source device 30 in FIGS. 10A and 10B, basically, as in the light source device 20 in FIGS. 4A and 4B, the solid light source 5, the phosphor layer 2, and the like. Are spaced apart from each other and the light emission is used in a reflective manner, so that higher brightness can be achieved compared to the conventional case.

  Further, in the light source device 30 shown in FIGS. 10A and 10B, since the phosphor layer 2 that does not substantially contain a resin component is used, there is no discoloration due to heat, and light absorption is small. For this reason, it is possible to further increase the luminance.

  Here, the phosphor layer 2 substantially not containing a resin component means that the resin component normally used for forming the phosphor layer is 5 wt% or less of the phosphor layer. As a material for realizing such a phosphor layer, 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, or a phosphor polycrystal (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 layer mentioned here does not substantially contain a resin component and is composed only of an inorganic substance, discoloration due to heat does not occur. 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 layer 2 to the substrate 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 layer 2.

  The phosphor layer 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 light source 5 emits blue light as visible light, the phosphor layer 2 includes at least one kind of phosphor among phosphors such as green, red, and yellow, for example. It is out. When the solid-state light source 5 emits blue light as visible light, when the phosphor layer 2 contains, for example, green and red phosphors (the green and red phosphors are dispersed uniformly, for example) When the phosphor layer 2 is irradiated with blue light from the solid light source 5, illumination light such as white can be obtained as reflected light. Further, when the solid light source 5 emits blue light as visible light, for example, when the phosphor layer 2 contains only a yellow phosphor, the blue light from the solid light source 5 is emitted from the phosphor layer 2. When illuminating, illumination light such as white can be obtained as reflected light.

  Further, in the light source device 30 of FIGS. 10A and 10B, the heat dissipation substrate 6 includes light (luminescence (fluorescence) from the phosphor layer 2 excited by excitation light from the solid light source 5), and the phosphor layer. 2, the role of the reflecting surface for the light from the solid light source 5 that has not been absorbed by 2), the role of dissipating the heat dissipated from the phosphor layer 2 and the light diffusion layer 9, and the phosphor layer 2 and the light diffusion layer 9 also serves as a support substrate. For this reason, high light reflection characteristics, heat transfer characteristics, and workability are required. The heat dissipation substrate 6 can be a metal substrate, oxide ceramics such as alumina, non-oxide ceramics such as aluminum nitride, etc., but a metal substrate having particularly high light reflection characteristics, heat transfer characteristics, and workability is used. It is desirable to be done.

  In addition, an organic adhesive, an inorganic adhesive, low-melting glass, metal (metal brazing), or the like can be used for the joint 7 between the phosphor layer 2 and the heat dissipation substrate 6. The junction 7 also has a reflection surface for light (light emission (fluorescence) from the phosphor layer 2 excited by excitation light from the solid light source 5 and light from the solid light source 5 not absorbed by the phosphor layer 2). Since it plays a role and a role to dissipate heat from the phosphor layer, it is desirable to use a metal (metal brazing) having both high light reflection characteristics and heat transfer characteristics. Alternatively, a conductive adhesive containing a metal component can be used for the joint 7 between the phosphor layer 2 and the heat dissipation substrate 6.

  Further, it is desirable to use a reflective member 3 having a reflectance of 95% or more, particularly 99% or more, with respect to excitation light. This is because when the reflectance is low, the reflection member 3 may be heated and burnt when the excitation light intensity is high. Further, it is desirable that the reflection member 3 has a small diffuse reflection component. This is because the regular reflection component of the excitation light is efficiently irradiated toward the phosphor layer 2 and / or the light diffusion layer 9.

  The reflection angle adjusting means 22 may be of a general mechanism, and is not particularly limited. For example, a rotating shaft is provided at the center of the reflecting member 3, and the rotating shaft is provided. For example, the angle can be controlled by interlocking with the stepping motor.

  Further, it is desirable to use a light diffusion layer 9 having a large diffuse reflection component in the reflection at the light diffusion layer 9. Examples of such members include ceramic layers such as alumina and resin layers in which ceramic powder is dispersed.

  The light diffusion layer 9 is formed adjacent to the phosphor layer 2. This is necessary for adjusting the illumination light by changing the ratio of the irradiation area of the phosphor layer 2 and the light diffusion layer 9 of the regular reflection component of the excitation light. The light diffusion layer 9 may be disposed adjacent to the phosphor layer 2 and may be disposed so as to surround the periphery of the phosphor layer 2.

  10A and 10B, only one phosphor layer 2 is provided. For example, as shown in FIG. 14, a plurality of phosphor layers ( In the example of FIG. 14, a configuration in which two phosphor layers 2j and 2k) are laminated may be employed. In this case, for example, when the solid light source 5 emits blue light as visible light, the phosphor layer 2j is made of a green phosphor, and the phosphor layer 2k is a red phosphor. If it is used, illumination light such as white can be obtained as reflected light.

  Further, as shown in FIGS. 15A and 15B (FIG. 15A is a plan view, FIG. 15B is a cross-sectional view taken along line AA in FIG. 15A), and light diffusion. The layer 9 can also be formed over the entire outer periphery of the phosphor layer 2. In this case, it is possible to adjust the intensity of the diffuse reflected light by irradiating the light reflected by the reflecting member 3 to an appropriate position of the light diffusing layer 9, and it is also applicable to the case where a plurality of solid light sources 5 are arranged. It will be a thing.

  Further, in the light source device 30 of FIGS. 10A and 10B, the phosphor layer 2 and the light diffusion layer 9 may be fixed, but the phosphor layer 2 and the light diffusion layer 9 are configured to be movable. You can also For example, as shown in FIGS. 16A and 16B or FIGS. 17A and 17B, FIGS. 16A and 17A are plan views, FIG. 16B and FIG. FIG. 17B is a cross-sectional view taken along line AA in FIG. 16A and FIG. 17A, respectively, and the phosphor layer 2 and the light diffusion layer 9 are rotated about the rotation axis X. It can also be configured as a reflection type fluorescent rotating body 1 (rotated by a motor 4 or the like). That is, the reflection type fluorescent rotating body 1 can be realized by connecting the phosphor layer 2 and the light diffusion layer 9 and the heat dissipation substrate 6 to the motor 4 or the like. In the reflection type fluorescent rotating body 1, the heat dissipation substrate 6 and the joint 7 function as a reflection surface for excitation light and fluorescence. In addition, the shape of the heat dissipation substrate 6 may be a disk shape or a quadrangle. In addition, in order to ensure the stability of rotation, it is possible to cut out a part of the disk or to have a shape with a weight on the contrary.

  16A, 16B, 17A, and 17B, only one type of phosphor layer is used as the phosphor layer 2 of the reflective phosphor rotator 1. Yes. Specifically, in the examples of FIGS. 16A, 16B, 17A, and 17B, only the phosphor layer made of, for example, a yellow phosphor is used as the phosphor layer 2 of the reflective phosphor rotator 1. In this case, if a solid light source that emits blue light is used, illumination light such as white can be obtained as reflected light. Alternatively, in the examples of FIGS. 16A, 16B, 17A, and 17B, for example, each of green and red phosphors is uniform as the phosphor layer 2 of the reflective phosphor rotator 1, for example. Only the phosphor layer dispersed and mixed is used. In this case, if a solid light source that emits blue light is used, illumination light such as white can be obtained as reflected light. . However, the present invention is not limited to this, and various modifications are possible. That is, the phosphor layer 2 of the reflection type fluorescent rotator 1 can be configured such that at least one phosphor layer of green, red, yellow or the like is disposed. 18A and 18B show a configuration example of the phosphor layer 2 of the reflection type fluorescence rotator 1. FIG. 18A is a plan view, and FIG. 18B is a cross-sectional view taken along the line AA in FIG. 18A. 18 (a) and 18 (b) shows three types of phosphor layers 2a, 2b, and 2c (for example, a red phosphor layer 2a made of a red phosphor) as the phosphor layer 2 of the reflective phosphor rotator 1. And a green phosphor layer 2b made of a green phosphor and a yellow phosphor layer 2c made of a yellow phosphor are provided as phosphor regions divided into three equal parts. In this case, the solid light source 5 is blue. If a light emitting material is used, illumination light such as white can be obtained as reflected light when the reflective fluorescent rotator 1 is rotated. In addition, various modifications are possible.

  For example, in the above-described example of the reflection type fluorescent rotator 1, when using a plurality of phosphor layers, the phosphor layers are arranged side by side in the horizontal direction, as shown in FIGS. 19 (a) and 19 (b). In this way, a plurality of phosphor layers (in the example of FIGS. 19A and 19B, two phosphor layers 2j and 2k) may be stacked in a vertical direction (stacked). 19A is a plan view, and FIG. 19B is a cross-sectional view taken along line AA in FIG. 19A. In this case, for example, when the solid light source 5 emits blue light as visible light, the phosphor layer 2j is made of a green phosphor, and the phosphor layer 2k is made of a red phosphor. If a thing is used, illumination lights, such as white, can be obtained as reflected light.

  In this way, by configuring the phosphor layer 2 and the light diffusion layer 9 as the reflection-type fluorescence rotator 1 that rotates around the rotation axis X (rotates by the motor 4 or the like), that is, with respect to the solid light source 5 By rotating the phosphor layer 2 and the light diffusing layer 9, it is possible to disperse the places where the excitation light from the solid light source 5 hits, and to suppress the heat generation in the light irradiation section (by using this fluorescent rotator 1 In the first place, it is possible to suppress the heat generation of the phosphor), and thereby it is possible to further increase the brightness.

  FIG. 14, FIG. 15 (a), (b), FIG. 16 (a), (b), FIG. 17 (a), (b), FIG. 18 (a), (b), FIG. 19 (a) mentioned above. , (B), the specular reflection component of the excitation light reflected by the phosphor layer 2; 2j, 2k; 2a, 2b, 2c is reflected toward the phosphor layer 2 and / or the light diffusion layer 9. By providing the reflecting member 3 and the reflecting angle adjusting means 22 for adjusting the reflecting angle of the reflecting member 3, it is possible to further increase the use efficiency of the excitation light and further increase the brightness, and to provide illumination. The color of light can be adjusted to suppress color variation of illumination light and color variation during driving.

  Next, the light source device 20 of the first embodiment and the light source device 30 of the second embodiment will be described in more detail.

  In the light source device 20 of the first embodiment and the light source device 30 of the second embodiment, the solid-state light source 5 can be a light emitting diode or a semiconductor laser having a light emission wavelength from the ultraviolet light to the visible light region.

More specifically, in the light source device 20 of the first embodiment, the solid-state light source 5 is, for example, a light emitting diode or semiconductor laser that emits near ultraviolet light having an emission wavelength of about 380 nm using an InGaN-based material. Can be used. In this case, the phosphor of the phosphor layer 2 is excited by ultraviolet light having a wavelength of about 380 nm to about 400 nm. For example, the red phosphor has CaAlSiN ₃ : Eu ²⁺ , Ca ₂ Si ₅ N _8. : Eu ²⁺ , La ₂ O ₂ S: Eu ³⁺ , KSiF ₆ : Mn ⁴⁺ , KTiF ₆ : Mn ⁴⁺ can be used, and (Si, Al) ₆ (O, N) ₈ : Eu ²⁺ , BaMgAl ₁₀ O ₁₇ : Eu ²⁺ , Mn ²⁺ , (Ba, Sr) ₂ SiO ₄ : Eu ^2+, etc. can be used, and (Sr, Ca, Ba, Mg) ₁₀ (PO ^{_{4) 6 C l2: Eu 2+}} , BaMgAl 10 O 17: Eu 2+, LaAl (Si, Al) 6 (N, O) 10: Ce 3+ and the like can be used.

Further, in the light source device 20 of the first embodiment and the light source device 30 of the second embodiment, the solid-state light source 5 emits blue light having a light emission wavelength of about 460 nm using, for example, a GaN-based material. A diode, a semiconductor laser, or the like can be used. In this case, the phosphor of the phosphor layer 2 is excited by blue light having a wavelength of about 440 nm to about 470 nm. For example, the red phosphor has 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, Al) 1 ^{_{(O, N) 16: Eu}} 2+ or the like can be used.

As the phosphor layer 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 it uses as a fluorescent substance layer, it can take out from a fluorescent substance layer, and can utilize it, without losing excitation light and fluorescence by diffusion, Furthermore, the heat | fever which generate | occur | produced in the fluorescent substance layer can be dissipated efficiently. 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.

  Here, phosphor ceramics have a high refractive index with respect to air, and there are few things that cause scattering such as pores inside, and light is guided inside the ceramics. The light emission component emitted from the side surface increases, and the light emission component emitted in the front direction decreases. In order to solve this problem, the light emission component emitted in the front direction can be increased by providing an uneven light extraction structure by etching on the ceramic surface, mounting a lens, or providing a reflective layer on the side surface. Is also possible.

  Moreover, although a metal substrate, oxide ceramics, non-oxide ceramics, etc. can be used for the heat dissipation substrate 6, it is desirable to use a metal substrate having particularly high light reflection characteristics, 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 heat dissipation substrate 6 may be coated for the purpose of preventing reflection and corrosion. Further, the heat dissipation substrate 6 may be provided with a structure such as a fin in order to improve heat dissipation.

  In addition, an organic adhesive, an inorganic adhesive, low-melting glass, metal brazing, or the like can be used for the joint 7 between the phosphor layer 2 and the heat dissipation substrate 6. Among these, it is desirable to use metal brazing that can achieve both high reflectance and heat transfer characteristics. The ceramic (phosphor layer 2) and the metal substrate (heat dissipation substrate 6) can be joined by first forming a metal film on the ceramic side and brazing the metal film to 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. Further, as the metal 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 metal brazing material is placed 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.

  Further, it is desirable to use a reflective member 3 made of a metal member such as aluminum or stainless steel having a plate or block shape and a smooth surface. These surfaces may be coated with silver in order to improve the reflectance. The reflecting member 3 does not need to be composed only of these materials exhibiting high reflectivity, and the reflecting member is integrally formed by disposing a high reflectivity member on the surface of the low reflectivity member. May be.

  Further, as described above, a resin layer in which ceramics such as alumina or ceramic powder is dispersed can be used for the light diffusion layer 9. In the case of using alumina ceramics for the light diffusing layer 9, it is possible to bond the alumina ceramics adjacent to the phosphor layer 2 on the heat dissipation substrate 6 with an adhesive after processing the alumina ceramics to an arbitrary size. When using a resin layer in which ceramic powder is dispersed in the light diffusing layer 9, a resin sheet in which ceramic powder is dispersed is formed first, and is then attached to the phosphor layer sink. It is possible. As a method for forming the light diffusing layer 9, it is of course possible to employ methods other than those listed here.

  As described above, in the present invention, the solid-state light source 5 and the phosphor layer 2 are installed on the same side with respect to the heat radiating substrate 6 to provide a reflective light source device. Of course, if necessary, an optical element such as a lens can be inserted between the solid-state light source 5 and the phosphor layer 2.

  In addition, as described above, in the present invention, it is preferable in terms of efficiency to configure the light source device as a reflective type, but the present invention can also be applied to a transmissive type.

  Further, by combining the above-described various light source devices of the present invention with optical components such as a predetermined lens system, it is possible to provide an illumination device capable of increasing the brightness.

  FIG. 20 shows an illumination device 40 provided with a predetermined lens system 25 in the light extraction direction of the light source device 20 of the first embodiment. Further, FIG. 21 shows an illuminating device 50 provided with a predetermined lens system 26 in the light extraction direction of the light source device 30 of the second embodiment. 20 and 21, the illumination light from the light source devices 20 and 30 can be collected by the lens systems 25 and 26 and used for illumination.

The present invention can be used for general lighting, automobile headlamps, and the like.

DESCRIPTION OF SYMBOLS 1 Fluorescence rotating body 2 Fluorescent substance layer 3 Reflective member 4 Motor 5 Solid light source 6 Heat radiation board 7 Junction part 9 Light diffusion layer 22 Reflection angle adjustment means 25, 26 Lens system 20, 30 Light source device 40, 50 Illumination device

Claims (4)

A solid-state light source that emits light having a predetermined wavelength in a wavelength region from ultraviolet light to visible light 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. A phosphor layer containing at least one type of phosphor that emits light, wherein the solid-state light source and the phosphor layer are spatially separated, and at least fluorescence is extracted from a predetermined surface of the phosphor layer. It is a light source device, Comprising: The light source device characterized by having the reflection member which reflects the regular reflection component of the excitation light reflected in the said fluorescent substance layer toward the said fluorescent substance layer directly . A solid-state light source that emits visible light as excitation light, and a phosphor layer that includes at least one phosphor that is excited by excitation light from the solid-state light source and emits fluorescence having a wavelength longer than the emission wavelength of the solid-state light source. The solid-state light source and the phosphor layer are spatially separated from each other, and a light source device that extracts at least fluorescence from a predetermined surface of the phosphor layer, the light source being adjacent to the phosphor layer A diffusion layer is disposed, and a reflection member that directly reflects the specular reflection component of the excitation light reflected by the phosphor layer toward the light diffusion layer and / or the phosphor layer, and a reflection angle of the reflection member is adjusted. A light source device comprising a reflection angle adjusting means. A solid-state light source that emits visible light as excitation light, and a phosphor layer that includes at least one phosphor that is excited by excitation light from the solid-state light source and emits fluorescence having a wavelength longer than the emission wavelength of the solid-state light source. A solid-state light source and the phosphor layer are spatially separated from each other, and a color adjustment method in a light source device that extracts at least fluorescence as illumination light from a predetermined surface of the phosphor layer, A light diffusing layer is disposed adjacent to the body layer, and the regular reflection component of the excitation light reflected by the phosphor layer is directly reflected by the reflecting member toward the light diffusing layer and / or the phosphor layer. A color adjustment method, wherein the color of the illumination light is adjusted by adjusting a reflection angle of a member to change a ratio of an irradiation area of a regular reflection component of excitation light to a phosphor layer and a diffusion layer. An illuminating device using the light source device according to claim 1.

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