TWI660157B - Light source device and ranging sensor provided with the same - Google Patents

Abstract

The light source device (10) includes a light source section (11) for radiating laser light, a condenser lens (12), and a translucent phosphor (13). The condenser lens (12) condenses the laser light emitted from the light source section (11). The translucent phosphor (13) is irradiated with laser light condensed by a condenser lens (12) to emit fluorescence.

Description

Light source device and ranging sensor provided with the same

The present invention relates to a light source device and a ranging sensor provided with the device.

In recent years, a light source device is used that combines a light source unit that emits blue laser light and a phosphor that is excited by blue laser light and emits fluorescence. For example, Patent Document 1 discloses a light source device which uses laser light emitted from a plurality of semiconductor lasers and focused by a condenser lens to excite the light source device in order to reduce the size and brightness of the light source device. A plurality of phosphors having the same fluorescent light are configured such that a light emitting point of each semiconductor laser and each phosphor are in a conjugate relationship with each other through a condenser lens. [Prior Art Literature] [Patent Literature] [Patent Literature 1] Japanese Patent Laid-Open No. 2013-120735 [Patent Literature 2] Japanese Patent No. 5649202 [Patent Literature 3] Japanese Patent Laid-Open No. 2007-148418

However, the prior light source device has problems as shown below. That is, in the light source device disclosed in the above publication, the phosphor is formed by being mixed with an adhesive such as a resin. Therefore, when the laser light emitted from the semiconductor laser is irradiated to the phosphor, the laser light is on the phosphor. Scattering occurs inside. Therefore, when the fluorescent light is led in a specific direction, the fluorescent light emitted from the phosphor cannot be efficiently derived, and it is difficult to obtain a light source with sufficiently high brightness. In addition, Patent Document 2 describes a light source device using a single-crystal phosphor without using a binder such as a resin. However, if only a single crystal phosphor is irradiated with laser light, it is difficult to obtain a light source with sufficiently high brightness. An object of the present invention is to provide a light source device that can obtain a light source with higher brightness than the conventional one, and a distance measuring sensor including the same. [Means for Solving the Problem] The light source device according to the first invention includes a light source unit that radiates laser light, a condenser lens, and a translucent phosphor. The condenser lens condenses the laser light emitted from the light source unit. The translucent phosphor is irradiated with laser light condensed by a condenser lens to emit fluorescence. Here, the light-transmitting phosphor is irradiated with laser light radiated from the light source portion and condensed by a condenser lens, and fluorescent light excited by the laser light in the light-transmitting phosphor is used as the light source. Here, as the light source unit, for example, a semiconductor laser (laser diode (LD)) that irradiates blue laser light can be used. The condensing lens is not limited as long as it has a function of collecting laser light to a translucent phosphor. In addition, the condenser lens is preferably arranged such that a light-condensing point is provided on the surface or inside of the translucent phosphor. The translucent phosphor is, for example, a polyhedron or a spherical phosphor, and includes a single crystal phosphor and a translucent ceramic phosphor. In addition, the term "light-transmitting" refers to a characteristic in which there is almost no light scattering inside the phosphor irradiated by the laser light (including a characteristic in which there is no scattering), and means that a light-condensing point is formed in the inside of the phosphor ( spot). Thereby, the portion of the translucent phosphor that is irradiated with the laser light condensed by the condenser lens forms a fluorescent light source portion that emits fluorescent light excited by the laser light along the propagation direction of the laser light, and borrows Due to the characteristics of the light-transmitting phosphor, the emitted fluorescent light can be derived with almost no scattering of the laser light. As a result, the fluorescent light emitted from the fluorescent light source portion formed in the translucent phosphor can be efficiently derived, so that a light source having a higher brightness than before can be obtained. The light source device according to the second aspect is the light source device according to the first aspect, wherein the translucent phosphor has a fluorescent light source portion, and the fluorescent light source portion is formed in a portion where the laser light is condensed by a condenser lens. . Here, for example, in a block-shaped translucent phosphor having a rectangular parallelepiped shape, a fluorescent light source portion that is excited by laser light and emits fluorescence is formed in a portion where laser light is collected. Here, the fluorescent light source portion is formed in a direction in which laser light propagates in the translucent phosphor, and emits light in a portion irradiated by the laser light. Thereby, the laser light is irradiated to the translucent phosphor with almost no scattering, so that the power of the fluorescent light generated per unit volume of the fluorescent light source portion can be increased. This makes it possible to obtain a light source with higher brightness than before. A light source device according to a third aspect is the light source device according to the second aspect, wherein the fluorescent light source portion has a long, substantially cylindrical shape in a propagation direction of laser light radiated from the light source portion. Here, the fluorescent light source part formed in the irradiation part of the laser light in the inside of a translucent phosphor is formed in the substantially cylindrical shape along the propagation direction of laser light. Thereby, fluorescent light can be emitted from a substantially cylindrical fluorescent light source portion formed inside the translucent phosphor. The light source device according to the fourth aspect is the light source device according to any one of the first aspect to the third aspect, in which the laser light is condensed onto the surface or the inside of the translucent phosphor by a condenser lens. Here, the laser light is focused on the surface or inside of the translucent phosphor. Thereby, in the translucent phosphor, a fluorescent light source portion that is excited to emit fluorescence is formed in a portion where the laser light is collected. In addition, since the laser light is irradiated with almost no scattering from the surface to the inside of the translucent phosphor, the emitted fluorescence can be efficiently derived from a desired direction. A light source device according to a fifth invention is the light source device according to any one of the first to fourth inventions, and further includes a lens for introduction, and the lens for introduction is configured to perform fluorescent light emitted from the translucent phosphor. Spotlight. Here, an introduction lens is provided, which guides the fluorescence emitted from a portion (fluorescent light source portion) irradiated with laser light in the inside of the translucent phosphor. Thereby, the fluorescent light emitted from the translucent phosphor is led out from the direction of the lens for introduction in the translucent phosphor to the outside. Thereby, a light source with higher brightness than before can be obtained. A light source device according to a sixth aspect is the light source device according to the fifth aspect, wherein the lens for introduction is arranged so that a central axis of the lens is aligned with a central axis of laser propagation of laser light passing through the transmissive phosphor. Here, the lens for introduction is arranged such that the center axis of the lens and the light-emitting portion (fluorescent light source portion) of the light-emitting portion (fluorescent light source portion) formed in the direction of laser light propagation in the interior of the translucent phosphor are transmitted. The central axis is consistent. Thereby, the central axis of the lens for introduction is aligned with the central axis of the fluorescent light emitting portion (fluorescent light source portion) formed inside the translucent phosphor, and therefore the transmissive fluorescent light can be efficiently derived. Fluorescent light emitted from a light body. Thereby, a light source with higher brightness than before can be obtained. In addition, since the central axis of the lens for introduction is aligned with the central axis of a fluorescent light emitting portion (fluorescent light source portion) formed inside the translucent phosphor, the downstream side of the light source portion can be arranged. The optical system (condensing lens, introduction lens) is arranged on a straight line. Accordingly, the optical axis can be easily adjusted, and the optical system can be miniaturized. A light source device according to a seventh invention is the light source device according to the fifth or sixth invention, further comprising an optical fiber, and the optical fiber is irradiated with the fluorescent light condensed in the lens for introduction at the first end face, One end face is a second end face on the opposite side and emits fluorescence. Here, on the downstream side of the lens for introduction of the fluorescent light emitted from the inside of the translucent phosphor, an opposite side (the first side from which the fluorescent light incident from the lens for introduction is directed from the incident side (the first end surface) is disposed. (2 end faces) outgoing fiber. This allows light within the depth of field of the fluorescent light source portion to be introduced into the optical fiber. Therefore, fluorescent light can be introduced from the first end face of the optical fiber, and high-intensity light can be emitted from the second end face. In addition, the depth of field generally refers to an allowable amount of blur in the image plane of the lens as a practically focused range before and after the focus position on the object side. In the present invention, when the core diameter in the end face of the optical fiber is the diameter of the permissible astigmatism in the image plane of the lens, the depth of field formed on the object plane by the lens for introduction. Here, the end face of the optical fiber refers to a cross section in an end portion of the optical fiber to which the light collected by the introduction lens is incident. The core diameter refers to the inner diameter of a cylindrical core portion that transmits light in an optical fiber. The light source device according to an eighth aspect is the light source device according to any one of the first aspect to the seventh aspect, wherein the translucent phosphor is on an incident surface on which the laser light is incident, and an exit surface on which the fluorescent light is emitted. At least one of them has a convex curved surface. Here, at least one of the incident side and the outgoing side of the laser light in the translucent phosphor is a convex curved surface. Accordingly, when a convex curved surface is provided on the incident side, for example, the size in the radial direction of a concave mirror or the like provided between the condenser lens and the translucent phosphor can be reduced. On the other hand, when a convex curved surface is provided on the emission side, it is possible to suppress light divergence due to refraction at the interface between the translucent phosphor and air, and for example, it can be used for introduction arranged on the downstream side. The diameter of the lens is miniaturized. Further, when the convex curved surface is provided on both the entrance side and the exit side, both the effects on the entrance side and the effects on the exit side can be obtained. A light source device according to a ninth aspect is the light source device according to any one of the first aspect to the eighth aspect, wherein the translucent phosphor is a single crystal phosphor. Here, a single crystal phosphor is used as the translucent phosphor. This allows the laser light condensed by the condensing lens to propagate with almost no scattering inside the phosphor compared to the conventional phosphor containing a binder such as resin, so that the fluorescent light can be emitted efficiently. Thereby, a light source with higher brightness than before can be obtained. A light source device according to a tenth invention is the light source device according to any one of the first to ninth inventions, and further includes a concave mirror which is disposed on the incident surface side of the translucent phosphor and irradiates the light source unit. The laser light is transmitted, and the fluorescent light emitted to the incident surface side among the fluorescent light emitted from the transparent phosphor is reflected toward the transparent phosphor side. Here, a concave mirror that transmits laser light and reflects the fluorescent light is arranged on the incident surface side of the transparent phosphor, that is, between the condenser lens and the transparent phosphor. Here, the concave mirror may be a dichroic mirror or a perforated mirror having an opening through which laser light passes. Thereby, the laser light condensed by the condenser lens can be transmitted and irradiated to the light-transmitting phosphor, and the concave light can be used to radiate the light emitted from the light-transmitting phosphor to the light-transmitting property. The fluorescent light on the incident surface side of the fluorescent body is reflected in the direction of the light emitting position of the fluorescent light. As a result, since the fluorescent light emitted from the light-transmitting phosphor can be efficiently extracted by the concave mirror, a light source with higher brightness can be obtained. The light source device according to the eleventh invention is the light source device according to any one of the first to ninth inventions, and further includes a concave mirror which is arranged on the light-emitting side of the light-transmitting phosphor and irradiates the light source unit. The laser light is reflected by the translucent phosphor, and the fluorescence emitted from the translucent phosphor to the emission surface is transmitted. Here, a concave mirror that reflects laser light and transmits fluorescent light is disposed on the exit surface side of the translucent phosphor. Here, the concave mirror may be a dichroic mirror, a perforated mirror having an opening through which fluorescent light passes, and the like. Thereby, the fluorescent light emitted from the light-transmitting phosphor can be transmitted, and the laser light which is collected by the condenser lens and transmitted through the light-transmitting phosphor can be reflected toward the light emitting position by the concave mirror. As a result, the concave light can reflect the laser light transmitted through the light-transmitting phosphor to the light-transmitting phosphor again, thereby efficiently deriving the fluorescent light, so that a further high-brightness light source can be obtained. . The light source device according to a twelfth aspect is the light source device according to the tenth aspect or the eleventh aspect, wherein the concave mirror has a curved surface having a spherical surface or an aspheric surface centered on a light-condensing point of the laser light collected by the condenser lens. Here, the concave curved surface of the concave mirror is formed so as to be a spherical surface or an aspherical surface centered on the light-condensing point of the laser light collected by the condenser lens. As a result, the concave curved surface can be arranged with the light emitting portion (fluorescent light source portion) of the fluorescent light excited by the laser light condensed to the translucent phosphor as a center, so that fluorescent light or lightning can be arranged. The emitted light is efficiently reflected toward the light emitting position side of the fluorescent light. A light source device according to a thirteenth aspect is the light source device according to any one of the tenth aspect to the twelfth aspect, wherein the concave mirror is a dichroic mirror. Thereby, in the concave mirror provided on the incident surface side of the laser light in the translucent phosphor, the laser light can be transmitted, and the transmissive phosphor can emit light and be radiated to the phosphor on the incident surface side. Light is reflected in the direction of the light emitting position in the translucent phosphor. Alternatively, the concave mirror provided on the exit surface side of the translucent phosphor can transmit the fluorescent light emitted from the translucent phosphor, and can direct the laser light transmitted through the translucent phosphor to the The light emitting position in the translucent phosphor is reflected in the direction. As a result, it is possible to obtain a light source that is further enhanced in brightness. A ranging sensor according to a fourteenth invention includes the light source device according to any one of the first to thirteenth inventions, a light receiving unit, and a measuring unit. The light receiving unit receives reflected light of light radiated from the light source device. The measuring unit measures the distance from the object based on the amount of light received by the light receiving unit. Here, a ranging sensor is configured using the light source device. This makes it possible to use a light source with higher brightness than before, so that effects such as improved measurement accuracy and improved response speed can be obtained. The range-finding sensor of the fifteenth invention is the range-sensing sensor according to the fourteenth invention, wherein the light source device emits fluorescent light including a plurality of wavelengths, and the distance-measuring sensor further has fluorescent light passing therethrough. Chromatic aberration focus lens. The light receiving unit receives the reflected light of the fluorescent light irradiated to the object through the chromatic aberration focus lens. The measuring unit measures the distance from the object based on the wavelength of the fluorescent light whose light reception amount is maximized in the light receiving unit. Here, a confocal distance-measuring sensor is constructed by measuring a chromatic aberration focus lens, separating fluorescence by wavelength (by color), and detecting peaks of light of each wavelength to measure The distance from the object. As a result, as described above, the light source device that emits fluorescent light having a higher brightness than before has been used to construct the distance measuring sensor. Therefore, a high-performance confocal distance measuring sensor can be obtained. [Effects of the Invention] According to the light source device of the present invention, a light source having higher brightness than before can be obtained.

(Embodiment 1) A light source device 10 according to an embodiment of the present invention and a confocal measurement device (ranging sensor) 50 including the light source device 10 will be described below with reference to Figs. 1 to 4. (Confocal Measurement Device 50) As shown in FIG. 1, the confocal measurement device 50 equipped with the light source device 10 of the present embodiment is a measurement device that measures the displacement of the measurement target T using a confocal optical system. For example, the measurement target T measured by the confocal measurement device 50 has a cell gap of a liquid crystal display panel or the like. As shown in FIG. 1, the confocal measurement device 50 includes a head 51 and an optical system having a confocal point; a controller unit 53 which is optically connected via an optical fiber 52; and a monitor 54 which displays the output from the controller unit 53 Signal. The head portion 51 includes a diffraction lens (chromatic aberration focus lens) 51a in a cylindrical frame portion, an objective lens 51b disposed on the measurement object T side than the diffraction lens 51a, and an optical fiber 52 and a diffraction lens. Condensing lens 51c between 51a. The diffractive lens 51 a causes chromatic aberration in the optical axis direction of light emitted from a light source (for example, a white light source) that emits light of a plurality of wavelengths to be described later. The diffractive lens 51 a is periodically formed on the surface of the lens with a fine undulating shape such as a Kinoform shape or a binary shape (step shape, step shape). The shape of the diffractive lens 51a is not limited to the above-mentioned configuration. The objective lens 51 b condenses the light having the chromatic aberration in the diffraction lens 51 a to the measurement target object T. The condenser lens 51c is disposed between the optical fiber 52 and the diffractive lens 51a so that the numerical aperture of the optical fiber 52 is consistent with the numerical aperture of the diffractive lens 51a. The reason is that the light emitted from the white light source is guided to the head 51 through the optical fiber 52. In order to effectively use the light emitted from the optical fiber 52 by the diffractive lens 51a, it is necessary to make the numerical aperture (NA: Aperture is consistent with the numerical aperture of the diffractive lens 51a. The optical fiber 52 is an optical path from the head portion 51 to the controller portion 53 and also functions as a pinhole. That is, of the light condensed by the objective lens 51b, the light focused at the measurement target T is focused at the opening of the optical fiber 52. Therefore, the optical fiber 52 functions as a pinhole that blocks light of a wavelength that is not focused at the measurement target T and passes the light focused at the measurement target T. The confocal measurement device 50 may have a configuration in which the optical fiber 52 is not used in the optical path from the head 51 to the controller section 53. However, by using the optical fiber 52 in the optical path, the head 51 can be opposed to the controller section 53. Flexible movement. In addition, the confocal measurement device 50 needs to have a pinhole when it is a structure which does not use the optical fiber 52 in the optical path from the head part 51 to the controller part 53, but when it is a structure which uses the optical fiber 52, confocal The measurement device 50 does not need to have a pinhole. The controller section 53 internally includes a light source device 10 as a white light source, a branch fiber 56, a beam splitter 57, an imaging element (light receiving section) 58, and a control circuit section (measurement section) 59. The detailed configuration of the light source device 10 will be described in detail in the following paragraphs. The branch optical fiber 56 has one optical fiber 55a on the connection side with the optical fiber 52 forming the optical path from the head 51 to the controller section 53, and two optical fibers 15 and optical fibers 55b on the opposite sides of the connection side. The optical fiber 15 constitutes a part of a light source device 10 described later. The optical fiber 55b is connected to the beam splitter 57 so that the light condensed by the beam splitter 57 is introduced from the end surface. Therefore, the branch optical fiber 56 guides the light emitted from the light source device 10 to the optical fiber 52, and irradiates the measurement target T from the head 51. Further, the branch optical fiber 56 guides the light reflected from the surface of the measurement target T to the spectroscope 57 via the optical fiber 52 and the head 51. The beam splitter 57 includes a concave reflecting mirror 57a for reflecting the reflected light returned through the head 51, a diffraction grating 57b for entering the light reflected by the concave reflecting mirror 57a, and a condenser lens 57c for the self-diffractive grating. The light emitted from 57b is condensed. In addition, as long as the beam splitter 57 can distinguish the reflected light returned through the head 51 according to the wavelength, it may have any structure such as a Czerny-Turner type and a Littrow type. . The imaging device 58 is a line complementary metal oxide semiconductor (CMOS) or a charge coupled device (CCD) that measures the intensity of light emitted from the beam splitter 57. Here, in the confocal measurement device 50, a spectrometer 57 and an imaging element 58 constitute a measurement unit, and the measurement unit measures the intensity of the reflected light returned through the head 51 according to the wavelength. In addition, the measurement unit only needs to measure the intensity of the light returned from the head 51 in accordance with the wavelength, and may be configured by a single imaging device 58 such as a CCD. The imaging device 58 may be a two-dimensional CMOS or a two-dimensional CCD. The control circuit unit 59 controls operations of the light source device 10, the imaging element 58, and the like. In addition, although not shown, the control circuit unit 59 includes an input interface and an output interface that input signals for adjusting the operation of the light source device 10 or the imaging element 58 and the like. The output interface outputs the imaging element. 58 signal. The monitor 54 displays a signal output from the imaging element 58. For example, the monitor 54 draws a spectral waveform of the light returned from the head 51 and displays the displacement of the measurement target. In the confocal measurement device 50 of the present embodiment, a light source with high brightness can be obtained by mounting the following light source device 10. Thereby, as a measuring device, effects such as extending the measurement distance and improving responsiveness can be obtained. The configuration of the light source device 10 will be described in detail below. (Light Source Device 10) The light source device 10 according to this embodiment is mounted as a light source of the confocal measurement device 50. As shown in FIG. 2, the light source device 10 includes a light source section 11, a condenser lens 12, a light-transmitting phosphor 13, and an introduction. Use lens 14, and optical fiber 15. The light source unit 11 is, for example, a semiconductor laser that emits laser light having a peak wavelength of about 450 nm, and irradiates the laser light in the direction of the condenser lens 12 as excitation light for emitting fluorescent light in the translucent phosphor 13 . The condensing lens 12 is a lens having a convex surface on both the entrance surface and the exit surface, and condenses the laser light radiated from the light source portion to the inside of the translucent phosphor 13. The translucent phosphor 13 is, for example, a single crystal phosphor of yttrium aluminum garnet (YAG) doped with Ce ions, and has an incident surface 13a arranged along a plane perpendicular to the laser propagation direction, respectively. And the exit surface 13b. The translucent phosphor 13 emits fluorescent light having a wavelength in a range of 480 nm to 750 nm in a portion irradiated with the laser light collected from the light source unit 11 and condensed by the condenser lens 12. As shown in FIG. 3, in the translucent phosphor 13, a long and substantially cylindrical fluorescent light source portion 20 is formed in a portion where the laser light is irradiated along the propagation direction of the laser light. The fluorescent light source portion 20 is formed at a portion where the laser light passes through the inside of the translucent phosphor 13 and has a long, substantially cylindrical shape in the laser propagation direction as shown in FIGS. 3 and 4. Furthermore, since the fluorescent light source unit 20 emits fluorescent light in all directions in each unit, it can be regarded as a light source formed inside the translucent phosphor 13. Specifically, as shown in FIG. 4, the fluorescent light source portion 20 has a reduced-diameter portion having a reduced radius of a cross-sectional circle in a central portion in a long side direction along the propagation direction of the laser light, and has a cross-section toward both ends. A substantially cylindrical shape having a large radius. That is, the fluorescent light source unit 20 is formed so that the light-condensing point of the laser light is located at the cross-section 20b of the reduced-diameter portion. In addition, the fluorescent light source section 20 is formed such that the cross-sectional areas of the incident-side section 20a and the outgoing-side section 20c are larger than the diameter-reducing section section 20b in accordance with the convergence and diffusion of laser light. For example, the end face (incident side section 20a) of the fluorescent light source section 20 on the incident side of the laser light, the diameter-reduced section (diameter-reduced section section 20b) of the substantially cylindrical central portion, and the end surface (the emission side) of the laser light exit In section 20c), fluorescent light is emitted in all directions. Thereby, of the fluorescent light emitted from the fluorescent light source unit 20, the fluorescent light emitted in the depth of field is introduced through the introduction lens 14 and is condensed onto the end surface (first surface) of the optical fiber 15. In addition, the depth of field generally refers to an allowable amount of blur in the image plane of the lens, which is regarded as a practically focused range before and after the in-focus position on the object side. In the present embodiment, when the core diameter in the end face of the optical fiber 15 is set to the diameter of the permissible astigmatism in the image plane of the lens, the depth of field formed on the object surface by the introduction lens 14. Here, the end face of the optical fiber 15 refers to a cross section in an end portion of the optical fiber 15 to which light collected by the introduction lens 14 is incident. The core diameter refers to the inner diameter of a cylindrical core portion that transmits light in the optical fiber 15. As with the condenser lens 12, the introduction lens 14 is a lens having a convex entrance surface and an exit surface, and is disposed on the downstream side of the laser light propagation direction in the translucent phosphor 13. The introduction lens 14 condenses the fluorescent light emitted from the inside of the translucent phosphor 13 (fluorescent light source section 20) onto the end face of the optical fiber 15. Moreover, as shown in FIG. 3, the introduction lens 14 is arrange | positioned so that the lens center axis A2, and the center axis A1 of the laser light propagation in the inside of the translucent phosphor 13 may become coaxial (on the same straight line). As such, by arranging the central axis A1 of the laser propagation and the central axis A2 of the lens 14 for the introduction lens coaxially, the fluorescent light emitted from the fluorescent light source unit 20 can be efficiently directed from the first surface 15a to the first surface 15a. The optical fiber 15 is incident inside. The optical fiber 15 is one optical fiber constituting the branch optical fiber 56 of the confocal measurement device 50, and an optical path of light radiated from the head 51 of the confocal measurement device 50 is formed inside. In addition, as shown in FIG. 3, the optical fiber 15 has an end surface (first surface 15 a) on which fluorescent light collected by the introduction lens 14 is incident, and an end surface (second surface 15 b) on the emission side opposite to the end surface. Thereby, the optical fiber 15 can let the light incident from the 1st surface 15a be emitted from the 2nd surface 15b. In the light source device 10 according to this embodiment, as described above, as shown in FIG. 2, the laser light for excitation irradiated from the light source section 11 is condensed by the condenser lens 12 to a light-transmitting fluorescent light. The inside of the light body 13. As shown in FIG. 3, the introduction lens 14 condenses the fluorescent light generated by the condensing part of the laser light in the inside of the translucent phosphor 13 onto the first surface 15 a of the optical fiber 15. Here, in the light source device 10 according to the present embodiment, as described above, the inside of a single-crystal phosphor (light-transmitting phosphor 13) is irradiated with laser light condensed by a condenser lens 12. At this time, if the laser light is incident on a single-crystal phosphor (light-transmitting phosphor 13), in the phosphor, the light is transmitted to the inside of the phosphor while exciting the fluorescence with almost no diffusion. That is, in the light source device 10 of this embodiment, a single crystal phosphor (light-transmitting phosphor) that hardly scatters laser light incident into the inside is used. Therefore, compared with the conventional phosphor reinforced with an adhesive such as a resin, the fluorescent light emitted by the laser light incident into the interior can be efficiently derived, and therefore, a light source with higher brightness than before can be obtained. Embodiment 2 A light source device according to Embodiment 2 of the present invention will be described below with reference to FIGS. 5 to 7. The light source device 110 of this embodiment is different from the first embodiment in that a concave mirror 116 is provided between the condenser lens 12 and the translucent phosphor 13 as shown in FIG. 5. The other configurations of the light source device 110 are the same as those of the light source device 10 according to the first embodiment, and therefore the same reference numerals are used herein, and detailed descriptions of the configurations are omitted. As shown in FIG. 5, the light source device 110 according to this embodiment includes a light source section 11, a condenser lens 12, a concave mirror 116, a translucent phosphor 13, an introduction lens 14, and an optical fiber 15. The concave mirror 116 is disposed between the condenser lens 12 and the translucent phosphor 13, and a surface on the side of the translucent phosphor 13 has a concave reflective surface. In addition, the concave mirror 116 has a characteristic of transmitting laser light collected by the condenser lens 12 and reflecting fluorescent light emitted from the inside of the translucent phosphor 13. Thereby, the laser light radiated from the light source section 11 and condensed by the condenser lens 12 can be irradiated to the translucent phosphor 13 without being blocked by the concave mirror 116. Further, as shown in FIG. 6, the concave mirror 116 can be used to radiate the fluorescent light emitted from the fluorescent light source unit 120 formed in the transparent phosphor 13 in all directions to the condenser lens 12. The reflected fluorescent light returns to the side of the translucent phosphor 13. As a result, the introduction lens 14 can introduce more fluorescent light than the fluorescent light introduced in the first embodiment and collect light on the first surface 15a of the optical fiber 15. Therefore, it is possible to obtain higher brightness than before. Light source. Furthermore, the concave mirror 116 is arranged so that the center of the concave curved surface appears on the central axis A1 of the fluorescent light source unit 120. Thereby, the reflected fluorescent light can be condensed to the position of the fluorescent-emitting part (fluorescent light source part 120). As a result, more fluorescent light can be introduced into the introduction lens 14 than the fluorescent light introduced in the first embodiment and focused on the first surface 15 a of the optical fiber 15. Therefore, high brightness can be obtained more efficiently. Light source. The concave mirror 116 is more preferably a spherical or aspherical surface centered on the light-condensing point of the laser light in the translucent phosphor 13. Thereby, the reflected fluorescent light can be condensed to the fluorescent-emitting part (fluorescent light source part 120). As a result, more fluorescent light can be introduced into the introduction lens 14 than the fluorescent light introduced in the first embodiment and focused on the first surface 15 a of the optical fiber 15. Therefore, high brightness can be obtained more efficiently. Light source. In addition, as the concave mirror 116, a dichroic mirror or a lens formed by vapor-reflecting a reflective film for reflecting fluorescence on the concave surface of a meniscus lens can be used. A perforated mirror or the like that reflects fluorescent light in a flat surface. For example, when a dichroic mirror is used as the concave mirror 116, as shown in FIG. 7, by transmitting light having a wavelength of approximately 480 nm or less and reflecting light having a wavelength of approximately 480 nm or more, Laser light is transmitted while reflecting fluorescent light. Embodiment 3 A light source device according to Embodiment 3 of the present invention will be described below with reference to FIGS. 8 and 9. The difference between the light source device 210 of this embodiment and the first embodiment using the plate-shaped translucent phosphor 13 is that, as shown in FIG. 8, the light-transmitting phosphor having a convex exit side 213 b side is used.光 体 213. Light body 213. The other configurations of the light source device 210 are the same as those of the light source device 10 according to the first embodiment, and therefore the same reference numerals are used herein, and detailed descriptions of the configurations are omitted. As shown in FIG. 8, the light source device 210 of the present embodiment includes a light source section 11, a condenser lens 12, a translucent phosphor 213, an introduction lens 14, and an optical fiber 15. As shown in FIG. 9, the translucent phosphor 213 includes an entrance surface 213 a and an exit surface 213 b. In the translucent phosphor 213, a fluorescent light source unit 220 that emits fluorescence is formed in a portion where the laser light collected by the condenser lens 12 passes. The fluorescent light source unit 220 has substantially the same shape and function as the fluorescent light source unit 20 of the first embodiment. The incident surface 213a is a surface on the side of the condenser lens 12 and is arranged along a plane perpendicular to the propagation direction of the laser light. The exit surface 213 b is a surface on the side of the introduction lens 14 and has a curved surface that is convex toward the introduction lens 14. As a result, the fluorescent light excited by the laser light irradiated to the light-transmitting phosphor 213 is emitted from the emitting surface 213b. The occurrence of divergence is suppressed, and it is introduced into the introduction lens 14. As a result, the size of the introduction lens 14 can be reduced, and the size of the light source device 210 can be reduced. Alternatively, even when the size of the introduction lens 14 is fixed, since the degree of diffusion of the emitted fluorescence is suppressed, the amount of introduced fluorescence can be increased. This makes it possible to obtain a light source which is more efficiently brightened. Embodiment 4 A light source device according to Embodiment 4 of the present invention will be described below with reference to FIGS. 10 and 11. The light source device 310 of this embodiment is different from the first embodiment in that a concave mirror 316 is provided between the condenser lens 12 and the translucent phosphor 313 as shown in FIG. 10, and an incident surface and The light-transmitting phosphors 313 each having an exit surface having a convex curved surface. In addition, since the other configurations of the light source device 310 are the same as those of the light source device 10 according to the first embodiment, the same reference numerals are used herein, and detailed descriptions of the configurations are omitted. As shown in FIG. 10, the light source device 310 according to this embodiment includes a light source section 11, a condenser lens 12, a concave mirror 316, a translucent phosphor 313, an introduction lens 14, and an optical fiber 15. The concave mirror 316 is disposed between the condenser lens 12 and the translucent phosphor 313, and a surface on the side of the translucent phosphor 313 has a concave reflective surface. Further, the concave mirror 316 has a characteristic of transmitting laser light collected by the condenser lens 12 and reflecting the fluorescent light emitted from the inside of the translucent phosphor 313 as shown in FIG. 11. Thereby, the laser light irradiated from the light source section 11 and condensed by the condenser lens 12 can be irradiated to the translucent phosphor 313 without being blocked by the concave mirror 316. Further, as shown in FIG. 11, the concave mirror 316 can be used to radiate the fluorescent light source 320 formed inside the translucent phosphor 313 in all directions to the condenser lens 12 side. The reflected fluorescent light is returned to the translucent phosphor 313 side. As a result, the introduction lens 14 can introduce more fluorescent light than the fluorescent light introduced in the first embodiment and collect light on the first surface 15a of the optical fiber 15. Therefore, it is possible to obtain higher brightness than before. Light source. Further, as shown in FIG. 11, the concave mirror 316 is arranged so that the center of the concave curved surface appears on the central axis A1 of the fluorescent light source section 320. Thereby, the reflected fluorescent light can be condensed to the position of the fluorescent-emitting part (fluorescent light source part 320). As a result, more fluorescent light can be introduced into the introduction lens 14 than the fluorescent light introduced in the first embodiment and focused on the first surface 15 a of the optical fiber 15. Therefore, high brightness can be obtained more efficiently. Light source. The concave mirror 316 preferably has a spherical or aspheric shape centered on the light-condensing point of the laser light in the translucent phosphor 313 by the condenser lens 12. Thereby, the reflected fluorescent light can be condensed to the fluorescent-emitting part (fluorescent light source part 320). As a result, more fluorescent light can be introduced into the introduction lens 14 than the fluorescent light introduced in the first embodiment and focused on the first surface 15 a of the optical fiber 15. Therefore, high brightness can be obtained more efficiently. Light source. In addition, as the concave mirror 316, similarly to the concave mirror 116 of the second embodiment, a dichroic mirror or a lens obtained by vapor-depositing a reflective film reflecting fluorescence on the concave surface of a meniscus lens can be used. A perforated mirror or the like having an opening in a portion through which laser light passes and reflecting fluorescent light in a concave surface. As shown in FIG. 11, the translucent phosphor 313 includes an incident surface 313 a and an emission surface 313 b. The incident surface 313 a is a surface on the side of the condenser lens 12 and has a curved surface that is convex toward the condenser lens 12. As a result, the fluorescent light excited by the laser light irradiated to the translucent phosphor 313 is incident on the incident surface 313a. Due to the refractive index difference at the interface between the translucent phosphor 313 (YAG refractive index ≒ 1.8) and air. The divergence occurring is suppressed, and is introduced into the concave mirror 316. As a result, the size of the light source device 310 can be reduced by reducing the size of the concave mirror 316. Alternatively, even when the size of the concave mirror 316 is fixed, since the degree of diffusion of the emitted fluorescent light is suppressed, the amount of reflected fluorescent light in the concave mirror 316 can be increased. Thereby, it is possible to more efficiently obtain a light source with higher brightness by reflecting the fluorescent light by the concave mirror 316. On the other hand, the exit surface 313 b is a surface on the side of the introduction lens 14 and has a curved surface that is convex toward the introduction lens 14. As a result, the fluorescent light excited by the laser light radiated to the light-transmitting phosphor 313 is emitted from the light-emitting surface 313b due to the refractive index difference at the interface between the light-transmitting phosphor 313 (YAG index ≒ 1.8) and air. The occurrence of the diffusion is suppressed, and it is introduced into the introduction lens 14. As a result, the size of the introduction lens 14 can be reduced, and the size of the light source device 310 can be reduced. Alternatively, even when the size of the introduction lens 14 is fixed, since the degree of diffusion of the emitted fluorescence is suppressed, the amount of introduced fluorescence can be increased. This makes it possible to obtain a light source which is more efficiently brightened. Embodiment 5 A light source device according to Embodiment 5 of the present invention will be described below with reference to FIGS. 12 and 13. The light source device 410 of this embodiment is different from the first embodiment in that a concave mirror 416 is provided between the condenser lens 12 and the translucent phosphor 413 as shown in FIG. The translucent phosphor 413 having a convex curved surface. The other configurations of the light source device 410 are the same as those of the light source device 10 according to the first embodiment, and therefore the same reference numerals are used herein, and detailed descriptions of the configurations are omitted. As shown in FIG. 12, the light source device 410 according to this embodiment includes a light source section 11, a condenser lens 12, a concave mirror 416, a translucent phosphor 413, an introduction lens 14, and an optical fiber 15. The concave mirror 416 is disposed between the condenser lens 12 and the translucent phosphor 413, and the surface on the side of the translucent phosphor 413 has a concave reflective surface. The concave mirror 416 has a characteristic of transmitting laser light collected by the condenser lens 12 and reflecting the fluorescent light emitted from the inside of the translucent phosphor 413 as shown in FIG. 13. Thereby, the laser light radiated from the light source section 11 and collected by the condenser lens 12 can be irradiated to the translucent phosphor 413 without being blocked by the concave mirror 416. Furthermore, as shown in FIG. 13, the concave mirror 416 can be used to radiate the fluorescent light source portion 420 formed inside the translucent phosphor 413 in all directions to the condenser lens 12 side. The reflected fluorescent light returns to the side of the translucent phosphor 413. As a result, the introduction lens 14 can introduce more fluorescent light than the fluorescent light introduced in the first embodiment and collect light on the first surface 15a of the optical fiber 15. Therefore, it is possible to obtain higher brightness than before. Light source. Further, as shown in FIG. 13, the concave mirror 416 is arranged so that the center of the concave curved surface appears on the central axis A1 of the fluorescent light source section 420. Thereby, the reflected fluorescent light can be condensed to the position of the fluorescent-emitting part (fluorescent light source part 420). As a result, more fluorescent light can be introduced into the introduction lens 14 than the fluorescent light introduced in the first embodiment and focused on the first surface 15 a of the optical fiber 15. Therefore, high brightness can be obtained more efficiently. Light source. In addition, the concave mirror 416 is more preferably a spherical or aspherical surface centered on the light-condensing point of the laser light in the translucent phosphor 413 by the condenser lens 12. Thereby, the reflected fluorescent light can be focused on the fluorescent light emitting portion (fluorescent light source portion 420). As a result, more fluorescent light can be introduced into the introduction lens 14 than the fluorescent light introduced in the first embodiment and focused on the first surface 15 a of the optical fiber 15. Therefore, high brightness can be obtained more efficiently. Light source. In addition, as the concave mirror 416, similarly to the concave mirror 116 of the second embodiment, a dichroic mirror or a lens obtained by vapor-depositing a reflective film reflecting fluorescence on the concave surface of a meniscus lens can be used. A perforated mirror or the like having an opening in a portion through which laser light passes and reflecting fluorescent light in a concave surface. As shown in FIG. 13, the translucent phosphor 413 includes an incident surface 413 a and an emitting surface 413 b. The incident surface 413 a is a surface on the side of the condenser lens 12 and has a curved surface that is convex toward the condenser lens 12. The emission surface 413b is a surface on the side of the introduction lens 14 and is arranged along a plane perpendicular to the propagation direction of the laser light. As a result, the fluorescent light excited by the laser light irradiated to the light-transmitting phosphor 413 and emitted in all directions is incident on the incident surface 413a. The interface between the light-transmitting phosphor 413 (YAG refractive index ≒ 1.8) and the air The divergence caused by the refractive index difference in the medium is suppressed, and is introduced into the concave mirror 416. As a result, the size of the light source device 410 can be reduced by reducing the size of the concave mirror 416. Alternatively, even when the size of the concave mirror 416 is fixed, since the degree of diffusion of the emitted fluorescent light is suppressed, the amount of reflected fluorescent light in the concave mirror 416 can be increased. Thereby, it is possible to more efficiently obtain a light source with higher brightness by reflecting the fluorescent light by the concave mirror 416. Embodiment 6 A light source device according to Embodiment 6 of the present invention will be described below with reference to FIGS. 14 to 16. The light source device 510 according to this embodiment is different from the first embodiment in that a concave mirror 516 is provided between the translucent phosphor 13 and the introduction lens 14 as shown in FIG. 14. In addition, since the other configurations of the light source device 510 are the same as those of the light source device 10 according to the first embodiment, the same reference numerals are used herein, and detailed descriptions of the configurations are omitted. As shown in FIG. 14, the light source device 510 according to this embodiment includes a light source section 11, a condenser lens 12, a translucent phosphor 13, a concave mirror 516, an introduction lens 14, and an optical fiber 15. The concave mirror 516 is disposed between the translucent phosphor 13 and the lens 14 for introduction, and an incident surface on the side of the translucent phosphor 13 has a concave reflective surface. In addition, the concave mirror 516 has a characteristic of transmitting fluorescent light excited in the light-transmitting phosphor 13 and reflecting laser light transmitted through the light-transmitting phosphor 13. Thereby, the fluorescent light emitted from the fluorescent light source unit 120 formed in the translucent phosphor 13 in all directions can be radiated to the introduction lens 14 side without being introduced into the introduction lens 14 without being introduced. Will be blocked by the concave mirror 516. Further, as shown in FIG. 15, the laser light transmitted through the translucent phosphor 13 without being absorbed can be reflected by the concave mirror 516 and returned to the translucent phosphor 13 side. As a result, it is possible to introduce more excitation light into the light-transmitting phosphor 13 than the laser light irradiated in the first embodiment to excite the fluorescent light, so that a light source with higher brightness than before can be obtained. Further, as shown in FIG. 15, the concave mirror 516 is arranged so that the center of the concave curved surface appears on the central axis A1 of the fluorescent light source section 520. Thereby, the reflected laser light can be condensed again to the position of the fluorescent-emitting part (fluorescent light source part 520). As a result, it is possible to introduce more excitation light into the light-transmitting phosphor 13 than the laser light irradiated in the first embodiment to excite the fluorescent light, so that a light source with higher brightness than before can be obtained. In addition, the concave mirror 516 preferably has a spherical or aspherical shape centered on the light-condensing point of the laser light in the translucent phosphor 13 by the condenser lens 12. Thereby, the reflected laser light can be condensed again to the fluorescent-emitting part (fluorescent light source part 520). As a result, more fluorescent light can be introduced into the introduction lens 14 than the fluorescent light introduced in the first embodiment and focused on the first surface 15 a of the optical fiber 15. Therefore, high brightness can be obtained more efficiently. Light source. In addition, as the concave mirror 516, a dichroic mirror, or a lens obtained by vapor-depositing a reflective film for reflecting laser light on the concave surface of a meniscus lens can be used. For example, when a dichroic mirror is used as the concave mirror 516, as shown in FIG. 16, by reflecting light having a wavelength of approximately 480 nm or less and transmitting light having a wavelength of approximately 480 nm or more, Fluorescence is transmitted while laser light is reflected. [Other Embodiments] An embodiment of the present invention has been described above, but the present invention is not limited to the above-mentioned embodiment, and various changes can be made without departing from the gist of the invention. (A) In the fourth embodiment and the like, a light source device has been described as an example. The light source device uses a light-transmitting property having a convex curved surface on at least one of the incident surface and the exit surface side. Phosphor. However, the present invention is not limited to this. For example, as shown in FIGS. 17 (a) and 17 (b), a translucent phosphor 613 may be used. The translucent phosphor 613 includes an entrance surface 613 a and an exit surface 613 b. The incident surface 613a has a convex curved surface portion 613aa only at a portion where the laser light passes, and the exit surface 613b has a convex curved surface portion 613ba only at a portion where the fluorescent light passes. (B) In the said embodiment, the example which arrange | positioned the condenser lens so that laser light may be condensed to the inside of a translucent phosphor was demonstrated. However, the present invention is not limited to this. For example, the condenser lens may be arranged so as to condense the laser light onto the surface of the translucent phosphor. In this case, a substantially cylindrical fluorescent light source portion is formed from the light-condensing point on the surface of the translucent phosphor to the inside, so that the same effect as that of the embodiment can be obtained. In addition, if it is considered that a fluorescent light source portion is formed at the front and back with the focusing point as the center in the propagation direction of the laser light, it is preferable to use a light-condensing lens to condense the laser light in a translucent phosphor Is located closer to the inside than the surface of the translucent phosphor. (C) In the above-mentioned embodiment, an example was described in which a single-crystal phosphor was used as the translucent phosphor mounted on the light source device 10. However, the present invention is not limited to this. For example, a translucent ceramic phosphor may be used instead of a single crystal phosphor. (D) In the said embodiment, the light source device 10 etc. which are equipped with the lens for introduction | transmission, and an optical fiber as a structure were demonstrated as an example. However, the present invention is not limited to this. For example, the structure which does not have an introduction lens or an optical fiber may be set as the light source device of this invention. (E) In the above-mentioned embodiment, the example in which the present invention was applied to the light source device 10 of the confocal measurement device (ranging sensor) 50 was described. However, the present invention is not limited to this. For example, the distance measuring sensor equipped with the light source device of the present invention is not limited to a distance measuring sensor such as a confocal measuring device, and other distance measuring sensors may be used. In addition, as a light source device, the present invention can also be applied as a light source device for a headlight or an endoscope. [Industrial availability]

The light source device of the present invention has the effect of obtaining a light source with higher brightness than before. Therefore, it can be widely used as various light source devices.

10‧‧‧Light source device

11‧‧‧Light source department

12‧‧‧ condenser lens

13‧‧‧ translucent phosphor

13a‧‧‧ incident surface

13b‧‧‧ exit surface

14‧‧‧ lens for introduction

15‧‧‧ Optical Fiber

15a‧‧‧side 1

15b‧‧‧side 2

20‧‧‧Fluorescent light source section

20a‧‧‧incident side profile

20b‧‧‧diameter reduction section

20c‧‧‧ exit side profile

50‧‧‧ confocal measuring device (ranging sensor)

51‧‧‧Head

51a‧‧‧ Diffraction lens (chromatic aberration focus lens)

51b‧‧‧ Objective

51c‧‧‧ condenser lens

52‧‧‧optical fiber

53‧‧‧Controller Department

54‧‧‧Monitor

55a, 55b‧‧‧ Fiber

56‧‧‧ branch fiber

57‧‧‧ Beamsplitter

57a‧‧‧ concave mirror

57b‧‧‧diffraction grating

57c‧‧‧ condenser lens

58‧‧‧Image sensor (light receiving section)

59‧‧‧Control circuit section (measurement section)

110‧‧‧light source device

116‧‧‧Concave mirror

120‧‧‧Fluorescent light source section

210‧‧‧light source device

213‧‧‧Translucent phosphor

213a‧‧‧ incident surface

213b‧‧‧ exit surface

220‧‧‧Fluorescent light source section

310‧‧‧Light source device

313‧‧‧Translucent phosphor

313a‧‧‧ incident surface

313b‧‧‧ exit surface

316‧‧‧ concave mirror

320‧‧‧Fluorescent light source section

410‧‧‧light source device

413‧‧‧Translucent phosphor

413a‧‧‧ incident surface

413b‧‧‧ exit surface

416‧‧‧Concave mirror

420‧‧‧Fluorescent light source section

510‧‧‧light source device

516‧‧‧Concave mirror

520‧‧‧Fluorescent light source section

613‧‧‧Translucent phosphor

613a‧‧‧ incident surface

613aa‧‧‧curved section

613b‧‧‧ exit surface

613ba‧‧‧curved surface

A1‧‧‧Center axis

A2‧‧‧ lens central axis

T‧‧‧ measuring object

FIG. 1 is a schematic diagram showing a configuration of a confocal measurement device equipped with a light source device according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating a configuration of a light source device mounted in the confocal measurement device of FIG. 1. FIG. 3 is an enlarged view of a main part of the light source device in FIG. 2. FIG. 4 is a schematic diagram showing a shape of a fluorescent light source portion formed inside the translucent phosphor of FIG. 3. FIG. 5 is a schematic diagram showing a configuration of a light source device according to Embodiment 2 of the present invention. FIG. 6 is an enlarged view of a main part of the light source device in FIG. 5. FIG. 7 is a graph showing wavelength characteristics of a concave mirror (dichroic mirror) included in the light source device of FIG. 5. 8 is a schematic diagram showing a configuration of a light source device according to Embodiment 3 of the present invention. FIG. 9 is an enlarged view of a main part of the light source device in FIG. 8. FIG. 10 is a schematic diagram showing a configuration of a light source device according to Embodiment 4 of the present invention. FIG. 11 is an enlarged schematic view of a main part of the light source device in FIG. 10. FIG. 12 is a schematic diagram showing a configuration of a light source device according to Embodiment 5 of the present invention. FIG. 13 is an enlarged view of a main part of the light source device in FIG. 12. 14 is a schematic diagram showing a configuration of a light source device according to Embodiment 6 of the present invention. FIG. 15 is an enlarged view of a main part of the light source device in FIG. 14. FIG. 16 is a graph showing the wavelength characteristics of a concave mirror (dichroic mirror) included in the light source device of FIG. 14. 17 (a) and 17 (b) are a side view and a rear view showing the shape of a translucent phosphor included in a light source device according to another embodiment of the present invention.

Claims (14)

A light source device includes: a light source unit that irradiates laser light; a condenser lens that focuses the laser light irradiated from the light source unit; and a translucent phosphor that is irradiated by the condenser lens The condensed laser light emits fluorescence, wherein the translucent phosphor has a fluorescent light source portion, and the fluorescent light source portion is formed by condensing the laser light through the condenser lens part. The light source device according to claim 1, wherein the fluorescent light source unit has a long, substantially cylindrical shape in a propagation direction of the laser light radiated from the light source unit. The light source device according to item 1 or item 2 of the patent application scope, wherein the laser light is condensed to a surface or an inside of the translucent phosphor by the condenser lens. The light source device according to claim 1 or claim 2, further comprising an introduction lens that focuses the fluorescent light emitted from the translucent phosphor. The light source device according to item 4 of the scope of patent application, wherein the introduction lens has a central axis of the lens aligned with a central axis of laser propagation of the laser light passing through the translucent phosphor. The light source device according to item 4 of the scope of patent application, further comprising an optical fiber, and the optical fiber is irradiated with the fluorescent light condensed in the introduction lens at a first end face, and is self-contained with the first The fluorescent light is emitted from a second end surface whose end surface is the opposite side. The light source device according to claim 1 or claim 2, wherein at least one of the transmissive phosphor is on an incident surface on which the laser light is incident, and at least an outgoing surface on which the fluorescent light is emitted. One of them has a convex curved surface. The light source device according to item 1 or item 2 of the patent application scope, wherein the translucent phosphor is a single crystal phosphor. The light source device according to item 1 or 2 of the scope of patent application, further comprising a concave mirror disposed on the incident surface side of the translucent phosphor so that the light source irradiated from the light source unit The laser light is transmitted, and the fluorescent light emitted to the incident surface side among the fluorescent lights emitted from the transparent phosphor is reflected toward the transparent phosphor side. The light source device according to item 1 or item 2 of the scope of patent application, further comprising a concave mirror, which is arranged on the exit surface side of the translucent phosphor, and irradiates from the light source unit and passes through the light source unit. The laser light of the translucent phosphor is reflected, and the fluorescence emitted from the translucent phosphor to the emission surface side is transmitted. The light source device according to item 9 of the scope of application for a patent, wherein the concave mirror has a curved surface having a spherical surface or an aspheric surface centered on a condensing point of the laser light condensed by the condenser lens. The light source device according to item 9 of the scope of patent application, wherein the concave mirror is a dichroic mirror or a perforated mirror with an opening. A ranging sensor comprising: the light source device according to any one of claims 1 to 12 of a patent application scope; a light receiving unit; a reflected light that receives light emitted from the light source device; and a measurement device. The unit measures a distance from the object based on the amount of light received by the light receiving unit. The ranging sensor according to item 13 of the patent application scope, wherein the light source device emits fluorescent light including a plurality of wavelengths, and the ranging sensor further has a way to pass the fluorescent light. The chromatic aberration focus lens is configured such that the light receiving unit receives the reflected light of the fluorescent light irradiated to the object via the chromatic aberration focus lens, and the measuring unit is based on the light receiving unit. The wavelength of the fluorescent light having the largest amount of received light is measured, and the distance from the object is measured.