JP2010199027A - Light source device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device capable of enhancing utilization efficiency of fluorescence in a structure combining a plurality of optical fibers into one. <P>SOLUTION: The light source device includes a plurality of excitation light sources emitting excitation light, a plurality of light guide members guiding the excitation light, and a plurality of wavelength converting members receiving excitation light guided by the plurality of light guide members and emitting wavelength converting light having a different wavelength from the excitation light and different from one another. Each of the plurality of the wavelength converting members includes a side surface and a bottom surface on which excitation light is irradiated, and each forms a wavelength converting unit fixed at one retaining member on its side surface, and the wavelength converting unit is arranged at a focus or in the vicinity of a concave mirror. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a light source device capable of switching the color of emitted light.

  Conventionally, some endoscope apparatuses use a light source that sequentially switches red light, green light, and blue light and emits them. An example will be described with reference to FIG. FIG. 18 is a schematic configuration diagram showing a configuration of an endoscope apparatus using a conventional light source device.

  The endoscope apparatus 501 in FIG. 18 includes three excitation light sources 171 to 173 and is configured to be connected to fluorescent fibers 174 to 176, respectively. The fluorescent fibers 174 to 176 include a phosphor and an optical fiber that guides the fluorescence generated by the phosphor. Further, the fluorescent fibers 174 to 176 are connected to one optical fiber 502 at the coupling portion 191 so that the illumination light is guided to the emission end 103. Accordingly, when the three excitation light sources 171, 172, and 173 are sequentially turned on and off, the corresponding fluorescent fibers 174, 175, and 176 emit light, and are emitted from the emission end 103 via the coupling unit 191 and one optical fiber 502. It is configured to be possible.

JP 2003-19112 A

  However, in the conventional configuration, the fluorescence generated in the fluorescent fibers 174 to 176 is coupled to one optical fiber 502 by the coupling unit 191. However, these fluorescences are efficiently coupled by the coupling unit 191 of the optical fiber. It is difficult to couple to one optical fiber 502. As a result, in the configuration according to the conventional technique, there is a large loss for coupling the fluorescence guided through the plurality of optical fibers to the single optical fiber 502, and illumination light with sufficient brightness cannot be obtained.

  The present invention has been made in view of the above, and an object of the present invention is to improve the use efficiency of fluorescence in a configuration in which fluorescence guided through a plurality of optical fibers is guided to one optical fiber. The object is to provide a bright light source device.

  In order to solve the above-described problems and achieve the object, the present invention includes a plurality of excitation light sources that emit excitation light, a plurality of light guide members that guide the excitation light, and the plurality of light guide members. A plurality of wavelength conversion members for receiving the guided excitation light and emitting wavelength-converted lights having wavelengths different from the excitation light and different from each other, wherein the plurality of wavelength conversions Each of the members has a side surface and a bottom surface irradiated with the excitation light, and the plurality of wavelength conversion members are fixed to one holding member on the side surface to form a wavelength conversion unit, The wavelength conversion unit is arranged at or near the focal point of the concave mirror.

  According to a preferred aspect of the present invention, it is desirable that the surface of the holding member that fixes the plurality of wavelength conversion members is a reflection surface that reflects the excitation light and / or the wavelength conversion light.

  According to a preferred aspect of the present invention, it is desirable that the holding member is a columnar body having a plurality of wavelength conversion member attachment portions.

  Moreover, according to the preferable aspect of this invention, the side surface fixed to the said holding member of the said some wavelength conversion member is a plane, The said holding member has the plane corresponding to the side surface of the said several wavelength conversion member. It is desirable to have a polygonal column.

  Further, according to a preferred aspect of the present invention, the emission end of the light guide member is disposed so as to irradiate excitation light to the bottom surface of the plurality of wavelength conversion members and the region in contact with the holding member or the vicinity thereof. It is desirable.

  According to a preferred aspect of the present invention, the plurality of wavelength conversion members have a semi-cylindrical shape obtained by cutting a cylinder by a plane passing through the central axis thereof, and are fixed to the holding member by the cut surface. Is desirable.

  Further, according to a preferred aspect of the present invention, it is desirable that the light guide member is disposed so as to irradiate excitation light on the central axis of the cylinder or in the vicinity thereof on the bottom surface of the semi-cylinder.

  According to a preferred aspect of the present invention, the holding member is a columnar body having a number of concave surfaces corresponding to the plurality of wavelength conversion members, and the plurality of wavelength conversion members are columnar bodies having side surfaces, It is desirable that side surfaces of the plurality of wavelength conversion members are fixed to a concave surface of the holding member.

  Moreover, according to a preferable aspect of the present invention, it is desirable that the concave surface of the columnar body and the side surfaces of the plurality of wavelength conversion members have complementary shapes so as to be in contact with each other.

  Moreover, according to a preferable aspect of the present invention, it is desirable that the plurality of wavelength conversion members have a cylindrical shape.

  Moreover, according to a preferable aspect of the present invention, it is desirable that the light guide member is disposed so as to irradiate excitation light on a central axis of the cylinder or in the vicinity thereof.

  Moreover, according to a preferable aspect of the present invention, it is desirable that the holding member has a shape that also holds part of the bottom surfaces of the plurality of wavelength conversion members.

  The light source device according to the present invention has an effect that the fluorescence can be efficiently used even when the fluorescence from the plurality of phosphors is coupled to one optical fiber.

It is a fragmentary sectional view which shows the external appearance structure of the light source device which concerns on 1st Embodiment of this invention. It is a figure which shows the expansion perspective structure of the wavelength conversion unit of FIG. It is a figure which shows the isometric view structure of a holding member. It is a figure which shows the side surface structure of the wavelength conversion unit shown in FIG. It is the figure which looked at the wavelength conversion unit shown in FIG. 2 from the bottom face side of fluorescent substance. FIG. 3 is a bottom view of the phosphor of FIG. 2, schematically showing the optical path of fluorescence. It is the figure which looked at the wavelength conversion unit which concerns on the modification of 1st Embodiment from the bottom face side of fluorescent substance. It is a figure which shows the isometric view structure of the wavelength conversion unit of the light source device which concerns on 2nd Embodiment. It is a figure which shows the perspective structure of the holding member of FIG. FIG. 9 is a diagram illustrating a bottom surface configuration of the phosphor of FIG. 8 and schematically showing an optical path of fluorescence. It is a figure which shows the isometric view structure of the holding member which concerns on the 1st example of 3rd Embodiment. It is a figure which shows the perspective structure of the holding member which concerns on the 2nd example of 3rd Embodiment. It is a figure which shows the perspective structure of the holding member which concerns on the modification of the 1st example of 3rd Embodiment. It is a figure which shows the perspective structure of the holding member which concerns on the modification of the 2nd example of 3rd Embodiment. It is a fragmentary sectional view which shows the external appearance structure of the light source device which concerns on 4th Embodiment. It is a fragmentary sectional view which shows the external appearance structure of the light source device which concerns on the 1st modification of 4th Embodiment. It is a fragmentary sectional view which shows the external appearance structure of the light source device which concerns on the 2nd modification of 4th Embodiment. It is a schematic block diagram which shows the structure of the endoscope apparatus using the conventional light source device.

  Embodiments of a light source device according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited by this embodiment.

(First embodiment)
First, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a partial cross-sectional view showing an external configuration of the light source device 1 according to the first embodiment of the present invention. FIG. 2 is an enlarged perspective view of the wavelength conversion unit 300 of FIG. FIG. 4 is a diagram showing a perspective configuration of the holding member 34, FIG. 4 is a diagram showing a side configuration of the wavelength conversion unit 300 shown in FIG. 2, and FIG. 5 shows the wavelength conversion unit 300 shown in FIG. FIG. 6 is a bottom view of the phosphor 30 of FIG. 2 and schematically shows the optical path of fluorescence.

  As shown in FIG. 1, the light source device 1 according to the first embodiment of the present invention has a light source 10 composed of three semiconductor laser light sources 101, 102, and 103 as an excitation light source. In addition, the optical fiber 20 includes three optical fibers 201, 202, and 203 as a light guide member that guides excitation light emitted from the three semiconductor laser light sources 101, 102, and 103. The excitation light exit end 20a side of the optical fibers 201, 202, and 203 is connected to the wavelength conversion unit 300, and the three phosphors 30 (red) that are wavelength conversion members mounted on the wavelength conversion unit 300 The fluorescent light 301, the green fluorescent material 302, and the blue fluorescent material 303 (see FIG. 2) are each irradiated with excitation light.

  Fluorescence emitted from the phosphors 301, 302, and 303 included in the wavelength conversion unit 300 is irradiated toward the parabolic mirror 40 that is a concave mirror. Since the wavelength conversion unit 300 is disposed at the focal point of the parabolic mirror 40 or the region 106 in the vicinity thereof, the fluorescence emitted from the wavelength conversion unit 300 is converted into substantially parallel light via the reflecting surface 40a of the parabolic mirror 40, It is configured to irradiate from the opening 41 of the parabolic mirror 40 toward the outside.

  As shown in FIG. 2, in the present embodiment, the phosphors 301, 302, and 303 are all semi-cylindrical, that is, a plane 70 (see FIGS. 5 and 6) including the central axis O of the cylinder (see FIGS. 5 and 6). (Refer to Ref.). The phosphors 301, 302, and 303 are mounted on one holding member 34. As shown in FIG. 3, the holding member 34 has a regular triangular prism shape, and the phosphors 301, 302, and 303 have a cylindrical cut surface on each side surface (reflecting surface 34 a described later) of the regular triangular prism as shown in FIG. 2. 30a is fixed. The surface of the side surface of the holding member 34 is a reflection surface 34 a that reflects excitation light and fluorescence emitted from the phosphors 301 to 303. In the present embodiment, all three side surfaces are the reflecting surfaces 34a.

  As shown in FIGS. 4 and 5, the optical fibers 201, 202, and 203 are semicircular, circular center positions that are the bottom surfaces 30b of the phosphors 301, 302, and 303 (that is, the center axis O of the half cylinder is the bottom surface). It is attached so that the excitation light is irradiated at a position where it crosses 30b) or in the vicinity thereof. That is, a corner 33 formed by the side surface (reflecting surface 34a) of the holding member 34 in contact with the cylindrical cut surface 30a of the semicylindrical phosphor 30, and the bottom surface 30b of the phosphor 30, It is comprised so that excitation light may be irradiated to the vicinity.

  Next, the operation of the present invention will be described. As shown in FIGS. 1 and 2, when the semiconductor laser light sources 101, 102, and 103, which are excitation light sources, are turned on, excitation lights corresponding to the phosphors 301, 302, and 303 are emitted, and the optical fibers 201, 202, and 203 are connected. Via, the phosphors 301, 302, and 303 provided in the wavelength conversion unit 300 are respectively irradiated.

  Since the optical fibers 201, 202, and 203 are attached as shown in FIGS. 4 and 5, the excitation light emitted from the emission end 20a of the optical fibers 201, 202, and 203 is emitted from the phosphors 301, 302, and 303. Irradiation is performed from the vicinity of the center position of the semicircle, which is the bottom surface 30b, toward the inside of the phosphors 301, 302, and 303.

  At this time, the excitation light emitted from the emission surfaces of the optical fibers 201, 202, and 203 is radiated and spread according to the numerical aperture NA of the optical fibers 201, 202, and 203, and is refracted by each of the phosphors 301, 302, and 303. The light is refracted according to the rate and travels while spreading inside the phosphors 301, 302, and 303. In the present embodiment, the emission ends 20a of the optical fibers 201, 202, and 203 that emit the excitation light are configured to substantially coincide with the central axis O of the cylinder that is the base of the semi-cylinder. The excitation light traveling inside 30 also travels inside the phosphors 301, 302, and 303 so as to spread around the central axis O of the semicircular cylinder.

  Here, since the phosphors 301, 302, and 303 have a semi-cylindrical shape, approximately half of the excitation light travels from the cylindrical cut surface 30a of the phosphors 301, 302, and 303 toward the reflecting surface 34a of the holding member 34. Irradiated, reflected by the reflecting surface 34a, and travels again toward the inside of the phosphors 301, 302, and 303. In this state, as shown in FIG. 6, the optical path 251 of the excitation light reflected by the reflection surface 34a of the holding member 34 has advanced in the direction of mirror symmetry with respect to the reflection surface 34a in the traveling direction of the excitation light. The inside of the phosphor 30 travels a distance substantially equal to the optical path 252 of the excitation light.

  That is, since the excitation light passes through the inside of the phosphor 30 by substantially the same distance as when the excitation light is irradiated from the emission end 20a of the optical fibers 201, 202, 203 in the central axis O direction of the cylindrical phosphor. It can be said that the ratio of wavelength conversion by the semi-cylindrical phosphor 30 is substantially equal to that when the excitation light is irradiated along the central axis O of the cylinder without cutting from the emission end 20a.

  In addition, among the fluorescence generated inside the phosphors 301, 302, and 303, the fluorescence emitted in the direction of the reflection surface 34 a of the holding member 34 is similarly reflected by the reflection surface 34 a of the holding member 34 and the phosphors 301 and 302. , 303 through the inside of the phosphor. At this time, the distance that the fluorescence passes through the phosphors 301, 302, and 303 is substantially equal to the case where the excitation light is irradiated from the emission end 20a in the direction of the central axis O of the cylinder without being cut.

  Therefore, it can be said that the extraction efficiency of the generated fluorescence in the semi-cylindrical phosphor 30 is substantially equal to the case where there is no cutting (in the case of the cylindrical phosphor). As described above, the utilization efficiency of the excitation light is substantially equal to the case where the excitation light is irradiated from the emission end 20a to the central axis O of the cylinder without cutting or in the vicinity thereof. Therefore, when the reflectance of the reflecting surface 34a is sufficiently high, the amount of fluorescence emitted when the phosphor 30 is an uncut cylinder is limited to the arc-shaped side surface 30c side of the cut cylinder (semi-cylinder). It becomes possible to make it radiate | emit from.

  As described above, the plane 70 that passes through the central axis O of the cylinder from the semi-cylindrical phosphor 30 mounted in the wavelength conversion unit 300 according to the present embodiment with an amount of light substantially equal to that of the uncut cylindrical phosphor. It is the structure which can inject only in the direction of one space S (refer FIG. 6) divided | segmented by (4).

  In the wavelength conversion unit 300, such semi-cylindrical phosphors 301, 302, and 303 are fixed to the respective side surfaces (reflection surfaces 34 a) of the regular triangular prism holding member 34. Three colors of fluorescence are emitted from 303 toward three directions. These three colors of fluorescence are all irradiated toward the reflecting surface 40a (see FIG. 1) of the parabolic mirror 40, and are made substantially parallel light by the reflecting surface 40a of the parabolic mirror 40, and are externally transmitted from the opening 41 of the parabolic mirror 40. It is emitted toward As described above, since the three colors of fluorescence are emitted in parallel with each other, the coupling to the optical transmission path (for example, one optical fiber) disposed in the subsequent stage of the light source device of the present embodiment is a color-corrected lens. It is easy to use the system, that is, highly efficient optical coupling is facilitated.

By configuring the light source device 1 as described above, it is possible to emit a light amount substantially equal to that of the cylindrical phosphor from the semi-cylindrical phosphor 30. Furthermore, since the emitted fluorescence is emitted toward one space S (see FIG. 6) with respect to the plane 70 passing through the central axis O of the semi-cylinder, it is possible to increase the light intensity in a desired direction. It becomes. Furthermore, since the plurality of phosphors 30 can be arranged in a small region (that is, the focal point of the parabolic mirror 40 or the region 106 in the vicinity thereof) by using the polygonal column-shaped holding member, the parabolic mirror 40 The light can be emitted in the same direction.
Further, most of the fluorescence generated in the phosphors 301, 302, and 303 is irradiated to the reflecting surface 40a of the parabolic mirror 40 and the reflecting surface 34a of the holding member 34 without being irradiated to other phosphors. Therefore, it can be efficiently taken out from the parabolic mirror 40. As a result, the fluorescence generated by the phosphors 301, 302, and 303 can be used efficiently, and an efficient and bright light source device can be realized.
As described above, it is possible to realize the light source device 1 that has high utilization efficiency of excitation light and fluorescence and can emit bright multicolor fluorescence.

In this embodiment, an example in which three phosphors having different colors are used and three colors of fluorescence are emitted has been shown. However, in addition to this, two phosphors are disposed on two surfaces of the plate-like member. An attached one is also possible. In addition, a configuration in which n (where n is an integer of 4 or more) phosphors can be attached to each side surface of the n-prism and the same effect can be obtained (the same applies to other embodiments described later). is there.).
In the present embodiment, an example in which the parabolic mirror 40 is used as the concave mirror is shown. However, in addition to this, an elliptical mirror 42 shown in a first modification of the fourth embodiment to be described later can also be used. By using the elliptical mirror 42, it is possible to focus and irradiate a desired region with the fluorescence emitted from the phosphor 30 without using a lens or the like. Further, it is easy to couple to an optical transmission line arranged at a later stage, and optical coupling with light efficiency can be realized without using a lens or the like.

  In the present embodiment, the emission ends 20a of the optical fibers 201, 202, and 203 are disposed in the vicinity of the center positions of the semi-cylindrical phosphors 301, 302, and 303. However, the present invention is not limited to this. . Even if the emission ends 20a of the optical fibers 201 to 203 are arranged at any location on the bottom surface 30b of the phosphors 301, 302, and 303, the wavelength of the excitation light can be efficiently converted. That is, it is possible to obtain all effects other than the effect that the fluorescence emitted from the phosphor 30 in this embodiment can obtain the same distribution as the fluorescence emitted from the columnar phosphor before cutting.

(Modification of the first embodiment)
A wavelength conversion unit 301 according to a modification of the first embodiment will be described. FIG. 7 is a view of the wavelength conversion unit 301 according to the modification of the first embodiment as viewed from the bottom surface 31b side of the phosphor 31 including the three phosphors 311, 312, and 313.

  Unlike the semi-cylindrical phosphor 30 of the first embodiment, as shown in FIG. 7, the modification of the first embodiment is a prism having a square bottom surface and the side length of the bottom surface 31b is 2: 1. These are prismatic phosphors 311 to 313 that are cut so as to be rectangular. Even when such a prismatic phosphor 31 is used, the same effect as that of the semicircular phosphor 30 can be obtained.

  Furthermore, in the case of a three-dimensional phosphor having a flat surface on one surface to which the distal end portion 20a (see FIG. 1) of the optical fiber 20 (201, 202, 203) is connected, the emission surface from which the incident excitation light exits is emitted. Although the optical path length is different, the excitation light can be efficiently converted into fluorescence. Therefore, it is possible to obtain the effect that the excitation light can be efficiently converted into fluorescence, as in the first embodiment, regardless of the shape of the solid.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. 8 is a diagram illustrating a perspective configuration of the wavelength conversion unit 310 of the light source device according to the second embodiment, FIG. 9 is a diagram illustrating a perspective configuration of the holding member 134 of FIG. 8, and FIG. FIG. 8 is a diagram illustrating a bottom surface configuration of eight phosphors 130 and schematically showing an optical path of fluorescence.

  As shown in FIGS. 8 to 10, the wavelength conversion unit 310 of the light source device according to the present embodiment is adapted (complementary) to three cylindrical phosphors 130 (phosphors 1301 to 1303) and a cylindrical side surface 130 a. 1) is different from the wavelength conversion unit 300 of the light source device 1 according to the first embodiment shown in FIG. 1 in that the holding member 134 has a concave surface 134b.

  As shown in FIGS. 8 to 10, the phosphors 1301 to 1303 have a cylindrical shape, and a part of the cylindrical side surface 130 a is attached to the holding member 134. Further, the emission ends 20a of the optical fibers 201, 202, and 203 are irradiated so as to irradiate excitation light at or near the center position of the circle of the bottom surfaces 130b of the phosphors 1301 to 1303 (the point where the central axis O and the bottom surface 130b intersect). (See FIG. 10).

  As shown in FIG. 9, the holding member 134 is formed with concave portions 134b (complementary shapes) that coincide with the cylindrical side surfaces 130a of the phosphors 1301 to 1303 on the three side surfaces (reflecting surfaces 134a described later) of the triangular prisms. The surface of the holding member 134 including the recess 134b is a reflecting surface 134a that reflects the fluorescence emitted from the phosphors 1301 to 1303.

  Next, the operation of this embodiment will be described. The basic operation of the light source device according to the second embodiment is the same as that of the light source device 1 according to the first embodiment, in which the phosphor 130 is irradiated with excitation light and the fluorescence emitted from the emission center of the phosphor 130. The behavior is different. This behavior will be described with reference to FIG.

  In the present embodiment, the phosphor 130 has a cylindrical shape, and the optical fiber 20 that irradiates the excitation light is arranged so that the excitation light emitting ends 20a of the optical fibers 201, 202, and 203 are aligned with the central axis O of the cylinder. Has been. Therefore, the excitation light is emitted while spreading at a spread angle according to the numerical aperture NA of the optical fibers 201, 202, 203 toward the center position of the bottom surface 130b of the phosphor 130 (the position where the bottom surface 130b and the central axis O intersect), The emitted excitation light travels toward the inside of the phosphor 130 at an angle corresponding to the refractive index of the phosphor 130.

  The excitation light traveling inside the phosphor 130 is absorbed by the light emission center of the phosphor 130 and emits fluorescence that is wavelength-converted light. Accordingly, the fluorescence is emitted anywhere in the phosphor 130 where the excitation light can be irradiated. In addition, the emission direction of fluorescence is generally not related to the incident direction of excitation light, and can emit light in any direction.

  In the present embodiment, the fluorescence emitted from the phosphor 130 includes the fluorescence emitted from the phosphor 130 and directly applied to the parabolic mirror 40 (see FIG. 1), and without being emitted to the outside of the phosphor 130. The fluorescent member 1351 emitted from the holding member 134 to the concave portion 134b to which the fluorescent member 130 is attached and the fluorescent member 1352 emitted from the fluorescent member 130 to the outside and then reflected by the surface of the holding member 134, that is, the reflection surface 134a. There are two possible cases.

  Among these, the fluorescent light 1351 irradiated to the concave portion 134b of the holding member 134 without going out is emitted to the outside of the phosphor 130 through an optical path as shown in FIG. In addition, the fluorescence 1352 emitted to the holding member 134 after being emitted to the outside is reflected by the reflecting surface 134a. All of these lights are irradiated toward the parabolic mirror 40 (see FIG. 1).

  The cylindrical phosphor 130 of the present embodiment is formed from a material that is difficult to process, such as a single crystal phosphor, as compared to the semi-cylindrical phosphor 30 of the first embodiment. However, since it can be molded relatively easily, the phosphor itself can be downsized as compared with the first embodiment. In addition, by adopting a shape that is convenient for processing, such as a cylindrical shape, there is an advantage that the choices of phosphors are expanded.

  In this embodiment, an example in which there are three types of phosphors has been shown. However, as in the first embodiment, two or n phosphors can be used.

  Moreover, although the example of the cylinder was shown in this embodiment, it is not limited to this, The effect can be acquired also with various polygonal pillars, such as a prism.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 11 is a diagram showing a perspective configuration of the holding member 34 according to the first example of the third embodiment, and FIG. 12 shows a perspective configuration of the holding member 134 according to the second example of the third embodiment. FIG. The basic configuration of the light source device of the third embodiment of the present invention is the same as that of the first embodiment shown in FIG. 1, and the operation is the same as that of the first embodiment and the second embodiment. It is.

  In the first and second examples of the third embodiment of the present invention, as shown in FIGS. 11 and 12, holding members 34 and 134 for holding a semi-cylindrical phosphor 30 and a cylindrical phosphor 130, respectively. The first and second embodiments are different in that they include bottom surface holding portions 35 and 135 that also hold the bottom surfaces 30b and 130b of the phosphors 30 and 130.

The bottom surface holding part 35 of the first example is composed of two holding structural members 35a and 35b having a rectangular parallelepiped shape and the same dimensions. The holding component members 35a and 35b are fixed so as to be spaced apart at a predetermined interval in the short direction of the holding member 34 and to be parallel to the longitudinal direction. At least a part of the bottom surface 30b of the phosphor 30 is supported by the upper surfaces 37 of the holding component members 35a and 35b, and the phosphor 30 is restricted from moving downward (in FIG. 11) of the holding member 34. In addition, the bottom holding part 35 also functions as a positioning means for the optical fibers 201, 202, and 203 by separating both holding members 35 a and 35 b by the same dimensions as the outer diameters of the optical fibers 201, 202, and 203.
In the first example, the holding member 34 and the bottom surface holding portion 35 are separated from each other, but it goes without saying that both may be integrally formed.

The bottom surface holding portion 135 of the second example is an arc-shaped surface that is connected to the concave portion 134b and the side surface 134a at a substantially right angle. The bottom surface holding portion 135 supports at least a part of the bottom surface 130b of the phosphor 130, and restricts the phosphor 130 from moving downward (in FIG. 12) of the holding member 134.
By using such holding members 34 and 134, it is possible to hold the phosphors 30 and 130 more firmly and stably while maintaining the characteristics of the first and second embodiments. In addition, it is possible to realize the attachment with no displacement of the attachment positions of the phosphors 30 and 130.

(Modification of the third embodiment)
Next, a modification of the third embodiment of the present invention will be described with reference to FIGS. FIG. 13 is a diagram illustrating a perspective configuration of a holding member 34 according to a modification of the first example of the third embodiment, and FIG. 14 illustrates a holding member according to a modification of the second example of the third embodiment. FIG.

  The basic configuration of the light source device of the modified example of the first and second examples of the third embodiment of the present invention is the same as that of the first embodiment shown in FIG. This is the same as the first embodiment, the second embodiment, and the third embodiment.

  In modifications of the first and second examples of the third embodiment of the present invention, as shown in FIGS. 13 and 14, holding members 34 and 134 that hold the phosphors 30 and 130 are phosphors 30 and 130, respectively. First, second, and third embodiments in that they have bottom surface holding portions 35 and 135 that hold the bottom surfaces 30b and 130b of the optical fibers 201 and 202 and 203, and optical fiber holding portions 36 and 136. This is different from the holding member.

  A holding member 34 according to a modification of the first example of the third embodiment includes a bottom surface holding part 35 in which an optical fiber holding part 36 that is a recess is formed on one side surface of a substantially rectangular parallelepiped member. The bottom surface holding portion 35 is fixed to the side surface of the holding member 34 on the other side surface facing the one side surface on which the optical fiber holding portion 36 is provided.

  The radius of curvature of the optical fiber holding part 36 is approximately equal to the diameter of the optical fiber 20. Therefore, the optical fiber 20 is securely held by the optical fiber holding part 36. Further, the bottom surface 30 b of the phosphor 30 is supported by the upper surface 37 of the bottom surface holding part 35, so that the phosphor 30 is restricted from moving downward in the longitudinal direction of the holding member 34.

  A holding member 134 according to a modification of the second example of the third embodiment includes a cylindrical bottom holding part 135 that is complementary to the concave part 134b. The bottom surface holding part 135 has a through hole extending along the central axis P, that is, a fiber holding part 136, and the optical fiber 20 is accommodated in the fiber holding part 136. The bottom surface holding part 135 is fixed to the concave part 134 b of the holding member 134.

The upper surface 137 of the bottom surface holding part 135 supports the bottom surface 30 b of the phosphor 30, so that the movement of the phosphor 130 downward in the longitudinal direction of the holding member 34 is restricted.
In the modified examples of the first and second examples, the holding member 34 (134) and the bottom surface holding part 35 (135) are separated from each other, but it goes without saying that both may be integrally formed.

  By using the holding members 34 and 134, the phosphors 30 and 130 and the optical fiber 20 are held more firmly and stably while maintaining the characteristics of the first, second, and third embodiments. It becomes possible. In addition, since the mounting position of the optical fiber 20 with respect to the phosphors 30 and 130 can be made accurate, the amount of fluorescent light emitted can be further stabilized.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 15 is a partial cross-sectional view showing an external configuration of the light source device 101 according to the fourth embodiment.
This embodiment is different from the first to third embodiments in that the fluorescence emitted from the parabolic mirror 40 that is a concave mirror is incident on the bundle fiber 60 that is the second optical fiber. ing. In addition, although any wavelength conversion unit and fluorescent substance of embodiment mentioned above and its modification are applicable, the structure using the wavelength conversion unit 300 of FIG.2 and FIG.6 is demonstrated below.
For the sake of clarity, FIG. 15 omits the semiconductor laser 10 that is an excitation light source from the light source device shown in FIG. 1, and includes a condenser lens 50 and a bundle fiber 60 used in the light source device 101 of this embodiment. FIG.

  When the semiconductor lasers 101, 102, and 103 (see FIG. 1) are turned on, the emitted excitation light is applied to the phosphor 30 (130) of the wavelength conversion unit 300 via the optical fiber 20. The fluorescence emitted from the wavelength conversion unit 300 is applied to the reflecting surface 40a of the parabolic mirror 40, becomes substantially parallel light, and is emitted outward from the opening 41 of the parabolic mirror 40. The fluorescence emitted from the parabolic mirror 40 is collected by the condenser lens 50 and enters the incident end 60 a of the bundle fiber 60. That is, the incident end 60 a of the bundle fiber 60 is disposed at the focal point of the condenser lens 60, and the fluorescence emitted from the parabolic mirror 40 can be efficiently incident on the bundle fiber 60.

  With this configuration, the fluorescence emitted from the phosphor unit 300 can be efficiently incident on the bundle fiber 60, and bright illumination light can be emitted from the emission end of the bundle fiber 60. . As a result, it is possible to irradiate bright illumination light to various places such as a narrow place, in a liquid, and in the body.

(First Modification of Fourth Embodiment)
Next, a first modification of the fourth embodiment will be described with reference to FIG. FIG. 16 is a partial cross-sectional view showing an external configuration of a light source device 101 according to a first modification of the fourth embodiment.
The basic configuration and operation of this modification are almost the same as those of the fourth embodiment. As shown in FIG. 16, in this modification, an elliptical mirror 42 is used instead of the combination of the parabolic mirror 40 and the condenser lens 50 in the fourth embodiment.

  That is, the wavelength conversion unit 300 is disposed at the first focal point 110 of the elliptical mirror 42 that is a concave mirror, and the incident end 60a of the bundle fiber 60 is disposed at the second focal point 120 of the elliptical mirror. With this configuration, the condenser lens 50 required in the fourth embodiment is not necessary, and a simpler and more compact light source device 101 can be realized.

(Second Modification of Fourth Embodiment)
Next, a second modification of the fourth embodiment will be described with reference to FIG. FIG. 17 is a partial cross-sectional view showing an external configuration of a light source device 101 according to a second modification of the fourth embodiment.
In this modification, the basic configuration and operation are the same as those in the first modification of the fourth embodiment. As shown in FIG. 17, the second modification of the fourth embodiment differs from the first modification of the fourth embodiment in that a spherical mirror 44 is added.

  The spherical mirror 44 is disposed so that the focal point thereof coincides with the first focal point 110 of the elliptical mirror 42 on which the phosphor unit 300 is disposed. The reflection surface 42a of the elliptical mirror 42 is emitted from the phosphor unit 300, and is not irradiated onto the elliptical mirror 42 but directly emitted to the outside. The fluorescent light is again focused on the spherical mirror 44, that is, the first focal point 110 of the elliptical mirror 42. Reflect in the direction. Such fluorescence is applied to the elliptical mirror 42 via the wavelength conversion unit 300 or the vicinity thereof, is reflected by the reflecting surface 42a, and enters the bundle fiber 60.

  By configuring in this way, it is possible to realize a bright light source device 101 with higher fluorescence utilization efficiency compared to the first modification of the fourth embodiment.

  In all of the embodiments described so far, examples of using three sets of excitation light sources, optical fibers, and phosphors are shown, but the present invention is not limited to this. For example, a two-color light source using two sets of excitation light sources, optical fibers, and phosphors, and a multi-color light source using a combination of four or more sets are also possible.

  Moreover, although the example which uses a laser light source as an excitation light source was shown, as long as it can excite wavelength conversion members, such as fluorescent substance, what kind of light source can be utilized. For example, excitation light from an LED (Light Emitting Diode), a lamp light source, or the like can be guided to an optical fiber and used.

  Furthermore, although the example which used fluorescent substance as a wavelength conversion member was shown, as long as it converts the wavelength of the light of excitation light, what kind of thing can be utilized. For example, SHG (Second harmonic generation) can be used.

  The embodiment of the present invention described so far is merely an example, and various modifications can be made without departing from the gist of the present invention.

  The light source device according to the present invention is useful for various optical instruments, and is particularly suitable for an endoscope.

DESCRIPTION OF SYMBOLS 1, 101 Light source device 10, 101, 102, 103 Semiconductor laser 20, 201, 202, 203 Optical fiber 20a Output end 30, 301, 302, 303
130, 1301, 1302, 1303 Phosphor 30a Cylindrical cut surface 30b, 130b Bottom surface 30c Side surface 34, 134 Holding member 34a, 134a Reflecting surface 35, 135 Bottom holding portion 36, 136 Optical fiber holding portion 40 Parabolic mirror 40a Reflecting surface 41 Opening 42 Ellipsoidal mirror 42a Reflective surface 50 (condenser) 60 Condenser lens 60 Bundled fiber 60a Incident end 70 Plane 110, 120 Focus 130a Cylindrical side surface 134b Recess 300, 301

Claims (12)

A plurality of excitation light sources that emit excitation light, a plurality of light guide members that guide the excitation light, and excitation light guided by the plurality of light guide members are received at a wavelength different from that of the excitation light. A plurality of wavelength conversion members that emit wavelength-converted lights having different wavelengths, and a light source device comprising:
Each of the plurality of wavelength conversion members has a side surface and a bottom surface to which the excitation light is irradiated. The plurality of wavelength conversion members are fixed to one holding member on the side surface to form a wavelength conversion unit. And the wavelength conversion unit is disposed at or near the focal point of the concave mirror.   The light source device according to claim 1, wherein a surface of the holding member that fixes the plurality of wavelength conversion members is a reflection surface that reflects the excitation light and / or the wavelength conversion light.   The light source device according to claim 2, wherein the holding member is a columnar body having a plurality of wavelength conversion member attaching portions.   The side surface of the plurality of wavelength conversion members fixed to the holding member is a flat surface, and the holding member is a polygonal column having a flat surface corresponding to the side surface of the plurality of wavelength conversion members. Item 4. The light source device according to Item 3.   The emission end of the light guide member is disposed so as to irradiate excitation light to a bottom surface of the plurality of wavelength conversion members and a region in contact with the holding member or the vicinity thereof. Light source device.   The light source according to claim 5, wherein the plurality of wavelength conversion members have a semi-cylindrical shape obtained by cutting a cylinder along a plane passing through a central axis thereof, and are fixed to the holding member by the cut surface. apparatus.   The light source device according to claim 6, wherein the light guide member is disposed so as to irradiate excitation light on or near a central axis of a cylinder on a bottom surface of the semi-cylinder.   The holding member is a columnar body having a number of concave surfaces corresponding to the plurality of wavelength conversion members, the plurality of wavelength conversion members are columnar bodies having side surfaces, and the side surfaces of the plurality of wavelength conversion members are The light source device according to claim 3, wherein the light source device is fixed to a concave surface of the holding member.   The light source device according to claim 8, wherein the concave surface of the columnar body and the side surfaces of the plurality of wavelength conversion members have complementary shapes that are in contact with each other.   The light source device according to claim 9, wherein the plurality of wavelength conversion members have a cylindrical shape.   The light source device according to claim 10, wherein the light guide member is arranged to irradiate excitation light on a central axis of the cylinder or in the vicinity thereof.   The light source device according to claim 3, wherein the holding member has a shape that also holds part of the bottom surfaces of the plurality of wavelength conversion members.

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