JP2012212763A - Optical amplification component, and optical fiber amplifier and fiber laser apparatus using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical amplification component that excels in heat radiation, and an optical fiber amplifier and fiber laser apparatus therewith.SOLUTION: An optical amplification component 50 includes: an amplifying optical fiber 40 having a core 41 doped with an active element and cladding 42 for propagating excitation light; and an excitation fiber having a core 31 for propagating the excitation light. The amplifying optical fiber 40 has a disk-shaped winding portion 45 wound spirally with a central axis of the cladding 42 positioned on a plane FS, and in the winding portion 45, a side surface of the cladding 42 is exposed in a plane to form one disk surface. The excitation fiber 30 has a disk-shaped winding portion 35 wound spirally with a central axis of the core 31 positioned on a plane FS, and in the winding portion 35, a side surface of the core 31 is exposed in a plane to form one disk surface. The exposed surface 46 of the cladding 42 of the amplifying optical fiber 40 and the exposed surface 36 of the core 31 of the excitation fiber 30 are oppositely connected.

Description

  The present invention relates to an optical amplification component excellent in heat dissipation, and an optical fiber amplifier and a fiber laser device using the same.

  A fiber laser device using an optical fiber for amplification has excellent light condensing performance, a small beam spot with high power density can be obtained, and non-contact processing is possible. Used in various fields. In particular, the output of fiber laser devices used in the processing field and the medical field has been increased.

  An amplification optical fiber used in the fiber laser device includes a core to which an active element is added and a clad that covers the outer peripheral surface of the core. The pumping light propagating through the cladding of the amplifying optical fiber is absorbed by the active element, so that the active element is brought into an excited state, and the amplified element is propagated through the core by stimulated emission of the activated element in the excited state. The light is amplified and emitted. As a method for making the excitation light incident on the clad, an end pump method in which the excitation light is made incident from the end surface of the amplification optical fiber and a side pump method in which the excitation light is made incident from the side surface of the amplification optical fiber are known. The side pump method has an advantage that the excitation light can be gradually incident along the longitudinal direction of the amplification optical fiber, and the intensity of the excitation light can be prevented from locally increasing.

  In the following Patent Document 1, the content of using the side pump to enter the excitation light into the amplification optical fiber is described. Specifically, an excitation fiber is provided along the amplification optical fiber. Then, the portion along which the amplification optical fiber and the excitation fiber are lined is bundled by being repeatedly wound or bent so as to draw a loop.

US Patent Application Publication No. 2008/0174857

  However, according to the side pump system in the above-mentioned patent document, the amplification optical fiber and the pumping fiber that are aligned with each other are bundled, so that there is a problem that heat dissipation is poor.

  Accordingly, an object of the present invention is to provide an optical amplifying component having excellent heat dissipation, and an optical fiber amplifier and a fiber laser device using the same.

  In order to solve the above problems, an optical amplification component according to the present invention includes an amplification optical fiber having a core to which an active element is added, a cladding that propagates excitation light that excites the active element, and the excitation light. A pumping fiber having a propagating core, and the amplification optical fiber has a disk-shaped winding portion wound in a spiral shape so that a central axis of the cladding is positioned on a plane, In the winding portion of the amplification optical fiber, the side surface of the cladding is exposed in a planar shape so as to form one disk surface, and the excitation fiber is spirally wound so that the central axis of the core is positioned on the plane. A disk-shaped winding portion wound in a shape, and in the winding portion of the excitation fiber, a side surface of the core is exposed in a planar shape so as to form one disk surface, and the amplification light The exposed surface of the cladding of the fiber; , And the exposed surface of the core of the excitation fiber is characterized in being connected to face.

  In such an optical amplification component, the cladding of the amplification optical fiber whose side surface is exposed in a planar shape is connected to the core of the excitation fiber whose side surface is exposed on the plane. Therefore, excitation light can be incident on the cladding of the amplification optical fiber from the side surface, and a side pump can be realized. Then, the amplification optical fiber is wound in a spiral shape so that the central axis of the cladding is located on a plane, and the excitation fiber is wound in a spiral shape so that the central axis of the core is located on the plane. Each of the winding parts has a disc shape (usually a disc shape). Therefore, compared with the case where the amplification optical fiber and the excitation fiber are bundled as in Patent Document 1, the surface area of the optical amplification component can be increased, and a structure with excellent heat dissipation can be obtained.

  Furthermore, it is preferable that the amplification optical fiber and the excitation fiber are wound non-parallel to each other.

  In this case, when the pumping light traveling along the pumping fiber enters the amplification optical fiber, the traveling direction of the pumping light is disturbed. Therefore, the skew mode of the pumping light in the amplification optical fiber can be suppressed.

  In this case, the amplification optical fiber and the excitation fiber may be wound in opposite directions.

  By doing so, the amplification optical fiber and the excitation fiber can be surely made non-parallel.

  Alternatively, it is preferable that the amplification optical fiber and the excitation fiber are wound in parallel with each other.

  Since the amplification optical fiber and the excitation fiber are parallel, the area where the exposed surface of the excitation fiber and the exposed surface of the amplification optical fiber are connected can be increased. More excitation light can be incident on the fiber.

  The clad of the optical fiber for amplification includes an inner clad made of glass surrounding a core to which the active element is added, and an outer clad made of resin having a refractive index equivalent to the inner clad surrounding the inner clad It is preferable that a part of the outer cladding is exposed in a planar shape.

  Since the resin can be easily cut and polished, by having an outer clad made of resin, the clad of the optical fiber for amplification can be easily exposed in a planar shape by cutting or polishing. Moreover, since the inner cladding is made of glass, the loss of excitation light can be reduced.

  The core of the excitation fiber includes an inner core made of glass, and an outer core that surrounds the inner core and is made of a resin having a refractive index equivalent to that of the inner core. It is preferably exposed in a planar shape.

  Also in the excitation fiber, by having an outer core made of resin, the core can be easily exposed in a planar shape by cutting or polishing. Moreover, since the inner core is made of glass, the loss of excitation light can be reduced.

  Further, the winding portion of the amplification optical fiber and the winding portion of the excitation fiber are except for a portion where the core of the excitation fiber and the cladding of the amplification optical fiber are connected, It is preferable that the core of the excitation fiber and the low refractive index resin whose refractive index is lower than that of the cladding of the amplification optical fiber are covered.

  With such a configuration, the exposed surface in the core of the pump fiber and the exposed surface in the cladding of the optical fiber for amplification are not perfectly matched and connected, and at least a part of the exposed surface is part of the other. Even when the exposed surface does not overlap, the low refractive index resin can suppress the excitation light from being emitted from the core of the excitation fiber or the cladding of the amplification optical fiber.

  Moreover, it is preferable that at least one of the side opposite to the exposed surface of the excitation fiber and the side opposite to the exposed surface of the amplification optical fiber is connected to a heat sink.

  By providing a heat sink, the heat dissipation can be further improved. Further, as described above, the winding portion in which the excitation fiber and the amplification optical fiber are wound in a spiral shape has a disk shape as a whole. Therefore, the connection surface of the heat sink can be made flat, and the heat sink can be easily provided.

  Further, a pumping fiber similar to the pumping fiber is further provided as a second pumping fiber, and the second pumping fiber is a disk-shaped winding wound in a spiral shape so that the central axis of the core is located on a plane. A side surface of the core is exposed in a planar shape so as to form one disk surface, and the amplification optical fiber is connected to the excitation fiber. The exposed surface opposite to the exposed surface connected to the excitation fiber in the clad of the optical fiber for amplification is exposed in a planar shape so that the side surface opposite to the exposed surface forms the other disk surface. And the exposed surface of the core of the second excitation fiber are preferably connected to face each other.

  In this way, the amplification optical fiber is sandwiched between the excitation fiber and the second excitation fiber, and a side pump is realized by each of the excitation fiber and the second excitation fiber, so that stronger excitation light can be used as the amplification optical fiber. Can be introduced. Therefore, the laser output can be made stronger.

  An optical fiber amplifier according to the present invention includes the optical amplification component according to any one of the above and a pumping light source that emits the pumping light incident on the core of the pumping fiber. It is.

  In such an optical fiber amplifier, since the optical amplification component is excellent in heat dissipation, it can have excellent reliability.

  Further, the fiber laser device of the present invention includes the optical amplification component according to any one of the above, a seed light source that emits seed light incident on the core of the amplification optical fiber, and the core of the excitation fiber. And an excitation light source that emits the excitation light that is incident thereon.

  Alternatively, the fiber laser device of the present invention includes any one of the above-described optical amplification components, a pumping light source that emits the pumping light incident on the core of the pumping fiber, and one end side of the amplification optical fiber. A mirror that reflects at least a part of the light emitted by the active element excited by the excitation light, and a light that is provided on the other end of the amplification optical fiber and reflected by the first mirror. And a second mirror that reflects with a lower reflectance than the first mirror.

  In these fiber laser devices, since the optical amplification component is excellent in heat dissipation, it can have excellent reliability.

  As described above, according to the present invention, an optical amplification component having excellent heat dissipation, and an optical fiber amplifier and a fiber laser device using the same are provided.

1 is a diagram illustrating a fiber laser device according to a first embodiment of the present invention. It is a figure which shows the mode of the structure in a cross section perpendicular | vertical to the longitudinal direction of the excitation fiber of FIG. It is a figure which shows the mode of the structure in a cross section perpendicular | vertical to the longitudinal direction of the optical fiber for amplification of FIG. It is the figure which extracted and decomposed | disassembled the excitation fiber and the optical fiber for amplification from the optical amplification component of FIG. It is a figure which shows the mode of the structure of the cross section in the VV line of the optical amplification component of FIG. It is a one part enlarged view of an excitation fiber. It is a figure which shows the mode of the structure in a cross section perpendicular | vertical to the longitudinal direction of the excitation fiber which concerns on 2nd Embodiment of this invention. It is a figure which shows the mode of the structure in a cross section perpendicular | vertical to the longitudinal direction of the optical fiber for amplification which concerns on 2nd Embodiment of this invention. It is a figure which shows the optical amplification component which concerns on 2nd Embodiment of this invention from the same viewpoint as FIG. It is a figure which shows the optical amplification component which concerns on 3rd Embodiment of this invention from the same viewpoint as FIG. It is a figure which shows the optical amplification component which concerns on 4th Embodiment of this invention similarly to FIG. It is a figure which shows the optical amplification component which concerns on 5th Embodiment of this invention from the same viewpoint as FIG. It is a figure which shows the fiber laser apparatus which concerns on 6th Embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of an optical amplification component, an optical fiber amplifier using the optical amplification component, and a fiber laser device of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram showing a fiber laser device 1 according to a first embodiment of the present invention.

  As shown in FIG. 1, the fiber laser device 1 includes a seed light source 10 that emits seed light and an optical fiber amplifier 5 that amplifies the seed light. The optical fiber amplifier 5 emits pump light. And an optical amplification component 50 including an excitation fiber 30 that propagates excitation light emitted from the excitation light source and an amplification optical fiber 40 into which seed light and excitation light are incident. That is, the fiber laser device 1 is a MO-PA (Master Oscillator-Power Amplifier) type fiber laser device including the seed light source 10 and the optical fiber amplifier 5.

  The seed light source 10 is composed of, for example, a laser light source composed of a laser diode, or a Fabry-Perot type or fiber ring type fiber laser device. The seed light emitted from the seed light source 10 is not particularly limited. For example, when ytterbium (Yb) is added to the amplification optical fiber 40 as described later, a laser beam having a wavelength of 1070 nm is used. Is done. The seed light source 10 is connected to a seed light fiber 15 composed of a core and a clad covering the core, and the seed light emitted from the seed light source 10 passes through the core of the seed light fiber 15. Propagate. An example of the seed light fiber 15 is a single mode fiber. In this case, the seed light propagates through the seed light fiber 15 as single mode light.

  The excitation light source 20 is composed of a plurality of laser diodes 21. Excitation light emitted from each laser diode 21 is not particularly limited. For example, when Yb is added to the amplification optical fiber 40 as described later, the laser light has a wavelength of 915 nm. . The laser diodes 21 of the respective excitation light sources 20 are connected to the excitation port 22, and the excitation light emitted from the laser diode 21 propagates through the excitation port 22. An example of the pumping port 22 is a multimode fiber. In this case, the pumping light propagates through the pumping port 22 as multimode light. Each excitation port 22 is connected to the excitation fiber 30 in the combiner 23.

  FIG. 2 is a diagram illustrating a structure in a cross section perpendicular to the longitudinal direction of the excitation fiber 30. As shown in FIG. 2, the excitation fiber 30 has a core 31 and a clad 32 surrounding the outer peripheral surface of the core 31, and the refractive index of the clad 32 is made lower than the refractive index of the core 31. The core 31 is made of, for example, glass to which no dopant is added, and the clad 32 is made of, for example, an ultraviolet curable resin. Further, the diameter of the core 31 of the excitation fiber 30 is, for example, 300 μm, and the outer diameter of the clad 32 is, for example, 400 μm.

  FIG. 3 is a view showing a structure of a cross section perpendicular to the longitudinal direction of the amplification optical fiber 40. As shown in FIG. 3, the amplification optical fiber 40 includes a core 41, a clad 42 that surrounds the core 41, and a resin clad 43 that covers the clad 42. The refractive index of the clad 42 is lower than the refractive index of the core 41, and is further equivalent to the core of the pump fiber 30. Further, the refractive index of the resin clad 43 is made lower than the refractive index of the clad 42. As the material constituting the core 41, for example, an element such as germanium (Ge) that increases the refractive index and an active element such as Yb that is excited by excitation light emitted from the excitation light source 20 are added. Glass. Examples of such active elements include rare earth elements, and examples of rare earth elements include thulium (Tm), cerium (Ce), neodymium (Nd), europium (Eu), and erbium (Er) in addition to Yb. Can be mentioned. Furthermore, examples of the active element include bismuth (Bi) and chromium (Cr) in addition to the rare earth element. Moreover, as a material which comprises the clad 42, the material similar to the core 31 of the excitation fiber 30 can be mentioned, for example. In the case where an element such as Ge that increases the refractive index is not added to the material of the core 41, the material of the cladding 42 may be glass added with fluorine (F) or the like that decreases the refractive index. In this case, the material of the core 31 of the excitation fiber 30 may be glass added with fluorine (F) or the like. Moreover, as a material which comprises the resin clad 43, ultraviolet curable resin is mentioned, for example. The diameter of the core 41 of the amplification optical fiber 40 is 10 μm, and the outer diameter of the cladding 42 is the same as the outer diameter of the core of the excitation fiber 30. The outer diameters of the resin cladding 43 and the cladding 32 of the excitation fiber 30 are arbitrary.

  One end of the amplification optical fiber 40 is connected to the seed light fiber 15 described above, and the core of the seed light fiber 15 and the core 41 of the amplification optical fiber are optically coupled. On the other hand, nothing is connected to the other end of the amplifying optical fiber 40, which is the emission end.

  4 is an exploded view of the pump fiber 30 and the amplification optical fiber 40 extracted from the optical amplification component 50 of FIG. 1, and FIG. 5 is a cross-sectional view of the optical amplification component 50 of FIG. It is a figure which shows the mode of a structure.

  As shown in FIGS. 4 and 5, the optical amplification component 50 includes the amplification optical fiber 40, the excitation fiber 30, and a pair of heat sinks 61 and 62 as main components.

In the optical amplifying component 50, the amplification optical fiber 40, the amplification optical fiber 40 to each other adjoin without a gap, the central axis of the cladding 42 so as to be positioned on a flat surface FS _G, wound spirally, It is formed in a disk shape, and a portion wound in the spiral shape is a winding portion 45. Similarly, in the optical amplifier part 50, the excitation fiber 30, the excitation fiber 30 to each other adjoin without a gap, as the central axis of the core 31 is positioned on a plane FS _G parallel to the plane FS _P, a spiral It is wound and formed in a disk shape, and a portion wound in the spiral shape is a winding portion 35. In the present embodiment, the amplification optical fiber 40 and the excitation fiber 30 are wound in a disk shape at the respective winding portions 45 and 35. In the winding portions 45 and 35 of the amplification optical fiber 40 and the excitation fiber 30, the amplification optical fiber 40 and the excitation fiber 30 are wound, for example, about 10 to 50 times, respectively. In this embodiment, the amplification optical fiber 40 and the excitation fiber 30 are wound in the same direction from the inside to the outside as indicated by solid arrows in FIG. The optical fiber 40 and the pump fiber 30 are both wound at the same pitch and the same number of turns. That is, in the optical amplification component 50, the amplification optical fiber 40 and the excitation fiber 30 are wound in parallel with each other.

Further, as shown in FIG. 5, the amplification optical fiber 40 has a planar shape in which the side surface of the clad 42 is parallel to the plane FS _G so as to form one surface of the winding portion 45 in the winding portion 45. An exposed flat surface 46 is formed. Specifically, in a state where the amplification optical fiber 40 in a state where the clad 42 is not exposed is wound in a spiral shape, a part of the resin clad 43 and a part of the clad 42 are connected to the plane FS _G. Even parallel surfaces have been removed. Similarly the excitation fiber 30 at the winding portion 35, so as to form one board of the winding portion 35, the side surface of the core 31 is exposed in the plane FS _P parallel planar, planar exposed surface 36 Is formed. Specifically, particularly in a state where the excitation fiber 30 in a state where the core 31 is not exposed is wound spirally, a portion of the cladding 32, and the core 31 is removed until the plane parallel to the plane FS _P Has been.

  The exposed surface 46 of the cladding 42 of the amplification optical fiber 40 and the exposed surface 36 of the core 31 of the pump fiber 30 are connected to face each other. For this connection, an adhesive having a refractive index equivalent to that of the clad 42 of the amplification optical fiber 40 and the core 31 of the excitation fiber 30 is used. In the present embodiment, in the state where the exposed surface 46 of the amplification optical fiber 40 and the exposed surface 36 of the excitation fiber 30 are connected, as described above, the amplification optical fiber 40 and the excitation fiber 30 are They are wound in parallel to each other. Therefore, as shown in FIG. 5, in the optical amplification component 50, the exposed surface 46 of the amplification optical fiber 40 and the exposed surface 36 of the excitation fiber 30 face each other.

  The pump fiber 30 and the amplification optical fiber 40 are covered with a low refractive index resin 58 except for a portion where the core 31 of the pump fiber 30 and the clad 42 of the amplification optical fiber 40 are connected. The low refractive index resin 58 has a refractive index lower than the refractive index of the core 31 of the pump fiber 30 and the refractive index of the cladding 42 of the amplification optical fiber 40. An example of such a low refractive index resin 58 is a fluorinated acrylic resin. As will be described later, when the low refractive index resin 58 is polished, it is preferable that the Shore hardness of the low refractive index resin is 20 or more.

  In the excitation fiber 30, the core 31 is not exposed except in the winding part 35, and the cladding 42 is not exposed in the amplification optical fiber 30 except in the winding part 45. FIG. 6 is an enlarged view of a part of the excitation fiber 30. As shown in FIG. 6, a slope 37 is formed at the boundary between the portion of the excitation fiber 30 where the core 31 is not exposed and the portion where the core 31 is exposed. Therefore, in the excitation fiber 30, the core 31 is gradually exposed from the portion where the core 31 is not exposed to the portion where the core 31 is exposed. Similarly, a slope similar to the slope 37 of the excitation fiber 30 is formed at the boundary between the portion of the amplification optical fiber 40 where the cladding 42 is not exposed and the portion where the cladding 42 is exposed. Therefore, in the amplification optical fiber 40, the clad 42 is gradually exposed from the portion where the clad 42 is not exposed to the portion where the clad 42 is exposed.

  In this embodiment, a heat sink 61 is provided on the side opposite to the exposed surface 46 of the amplification optical fiber 40, and a heat sink 62 is provided on the side opposite to the exposed surface 36 of the excitation fiber 30. Each of the heat sinks 61 and 62 has a planar surface on the side of the amplification optical fiber 40 and the side of the excitation fiber 30, and each winding portion of the amplification optical fiber 40 and the excitation fiber 30 wound in a disk shape. 45 and 35 are easily connected. Further, fins 61a and 62a are provided on the side opposite to the excitation fiber 30 and on the side opposite to the amplification optical fiber 40, and the surface area is increased.

  The fiber laser device 1 configured as described above operates as follows.

  First, seed light having a predetermined wavelength is emitted from the seed light source 10, and excitation light having a predetermined wavelength different from the wavelength of the seed light is emitted from each laser diode 21 of the excitation light source 20. At this time, the wavelength of the seed light varies depending on the dopant added to the core 41 of the amplification optical fiber 40. For example, when Yb is added to the core 41 as described above, the wavelength of the seed light is set to 1070 nm as described above. For example, the wavelength is set to 915 nm as described above. The seed light emitted from the seed light source 10 propagates through the core of the seed light fiber 15, enters the core 41 of the amplification optical fiber 40, and propagates through the core 41. Further, the excitation light emitted from the excitation light source 20 propagates through the excitation port 22, enters the core 31 of the excitation fiber 30 in the combiner 23, and propagates through the core 31. In the optical amplification component 50, the excitation light exits from the exposed surface 36 of the core 31 of the excitation fiber 30 and enters the cladding 42 from the exposed surface 46 of the cladding 42 of the amplification optical fiber 40. In this way, the excitation light exits from the side surface of the core 31 of the excitation fiber 30 and enters from the side surface of the cladding of the amplification optical fiber 40. Accordingly, the excitation light gradually enters the amplification optical fiber 40 from the excitation fiber 30.

  As described above, in the excitation fiber 30, the core 31 is gradually exposed by the slope 37 from the portion where the core 31 is not exposed to the portion where the core 31 is exposed. Therefore, the pumping light is prevented from being emitted outside the pumping fiber 30 from the part where the core 31 is not exposed in the pumping fiber 30 to the part where the core 31 is exposed.

  As described above, the excitation fiber 30 and the amplification optical fiber 40 are covered with the low refractive index resin 58 except for the portion where the core 31 of the excitation fiber 30 and the clad 42 of the amplification optical fiber 40 are connected. Therefore, the pumping light emitted from the exposed surface 36 of the core 31 of the pumping fiber 30 is suppressed from being emitted to the outside, and the pumping light is efficiently amplified from the core 31 of the pumping fiber 30. The light can enter the clad 42 of the optical fiber 40 for use.

  The excitation light incident on the clad 42 of the amplification optical fiber 40 propagates mainly through the clad 42, and the activity added to the core 41 when the excitation light passes through the core 41 of the amplification optical fiber 40. It is absorbed by the element and excites the active element. The excited active element causes stimulated emission by seed light, the seed light is amplified by this stimulated emission, and is emitted from the core 41 at the other end of the amplification optical fiber 40 as emitted light.

  At this time, even when heat is generated in the winding portions 45 and 35 of the amplification optical fiber 40 and the excitation fiber 30 in the optical amplification component 50, the amplification optical fiber 40 and the excitation fiber 30 are wound in a disk shape. Therefore, the heat dissipation efficiency is good. Further, in this embodiment, since the heat sinks 61 and 62 are provided in the respective winding portions 45 and 35, the heat dissipation efficiency is further improved. 45 and 35 are cooled.

  Such an optical amplification component 50 is manufactured as follows.

  First, the required lengths of the amplification optical fiber 40 and the excitation fiber 30 are prepared.

  Then, the prepared amplification optical fiber 40 and the excitation fiber 30 are wound. At this time, using a jig such as a reel (not shown), the amplification optical fiber 40 is wound in a spiral shape so that the center axis of the amplification optical fiber 40 is positioned in a flat shape, thereby obtaining a disk shape. Similarly, the excitation fiber 30 is also wound in a spiral shape by using a jig such as a reel (not shown) so that the central axis of the excitation fiber 30 is positioned in a planar shape.

  Next, the wound portion 45 around which the amplification optical fiber 40 is wound is covered with a low refractive index resin 58. For example, if the low refractive index resin 58 is an ultraviolet curable resin, an ultraviolet curable resin that is a precursor of the ultraviolet curable resin is applied to the wound optical fiber 40. Then, the winding portion 45 of the amplification optical fiber 40 is irradiated with ultraviolet rays to cure the ultraviolet curable resin, so that the winding portion 45 of the amplification optical fiber 40 is covered with the low refractive index resin 58. To do. Similarly, the wound portion 35 around which the excitation fiber 30 is wound is covered with a low refractive index resin 58. The method of covering the winding portion 35 of the excitation fiber 30 with the low refractive index resin 58 may be the same as the method of covering the winding portion 45 of the amplification optical fiber 40 with the low refractive index resin 58.

  Next, the winding portion 45 of the amplification optical fiber 40 covered with the low refractive index resin 58 is formed with a plane on which the central axis of the amplification optical fiber 40 is positioned so as to form one surface of the winding portion 45. Polish to parallel surfaces. Specifically, the spiral surface of the winding part 45 covered with the low refractive index resin 58 is pressed against the polishing part of the wrapping machine and polished. When the clad 42 is exposed to a desired area in a planar shape, the amplification optical fiber 40 is separated from the polishing portion of the wrapping machine. Then, if necessary, the exposed surface 46 of the clad 42 is mirror-finished. For this processing, for example, CMP (Chemical-Mechanical Polishing) may be used. Similarly, the winding portion 35 of the excitation fiber 30 covered with the low refractive index resin 58 is parallel to the plane on which the central axis of the excitation fiber 30 is positioned so as to form one surface of the winding portion 35. Grind. The excitation fiber 30 may be polished in the same manner as the amplification optical fiber 40. Thus, the clad 42 of the amplification optical fiber 40 and the core 31 of the excitation fiber 30 are exposed in a planar shape.

  Next, the exposed surface 46 of the cladding 42 in the winding portion 45 of the amplification optical fiber 40 and the exposed surface 36 of the core 31 in the winding portion 35 of the excitation fiber 30 are opposed to each other and bonded with an adhesive (not shown). And integrate.

  In this way, the optical amplification component 50 shown in FIGS. 4 and 5 is obtained.

As described above, according to the optical amplification component 50 of the present embodiment, the amplification optical fiber 40 having the exposed surface 46 in which the side surface of the clad 42 is exposed in a planar shape and the side surface of the core 31 are exposed on the plane. The excitation fiber 30 having the exposed surface 36 is connected so that the exposed surfaces 46 and 36 face each other. Therefore, the pump light can be incident on the side surface of the clad 42 of the amplification optical fiber 40 from the side surface of the core 31 of the pump fiber 30, and a side pump can be realized. For this reason, since the excitation light gradually enters the amplification optical fiber 40 from the excitation fiber 30, it is possible to prevent the excitation light from concentrating on a part of the amplification optical fiber 40 and to efficiently amplify the light. . Then, the amplifying optical fiber 40, the center axis of the clad 42 is coiled so as to be positioned on a flat surface FS _G, and excitation fiber 30, the central axis of the core 31 is positioned on the plane FS _P Thus, in the state where the exposed surfaces 36 and 46 are connected, the winding portions 35 and 45 in which the excitation fiber 30 and the amplification optical fiber 40 are wound in a spiral shape are provided. As a whole, it becomes a disk shape. Therefore, the optical amplifying component 50 can increase the surface area compared with the case where the amplification optical fiber and the excitation fiber are bundled, and excellent heat dissipation can be obtained.

  Thus, the optical fiber amplifier 5 and the fiber laser device 1 of the present embodiment can have excellent reliability because the optical amplification component 50 is excellent in heat dissipation.

  Further, as described above, in the optical amplification component 50, the amplification optical fiber 40 and the excitation fiber 30 are parallel to each other. Accordingly, the area where the exposed surface 36 of the pump fiber 30 and the exposed surface 46 of the amplification optical fiber 40 are connected can be increased, and more pump light is incident from the pump fiber 30 to the amplification optical fiber 40. be able to.

  Further, each of the winding portions 45 and 35 of the amplification optical fiber 40 and the excitation fiber 30 has a low refractive index except for a portion where the core 31 of the excitation fiber 30 and the clad 42 of the amplification optical fiber 40 are connected. Since it is covered with the resin 58, it is possible to suppress the excitation light from being emitted from the core 31 of the excitation fiber 30 or the cladding 42 of the amplification optical fiber 40.

  Moreover, the winding parts 35 and 45 around which the excitation fiber 30 and the amplification optical fiber 40 are wound in a spiral shape as described above have a disk shape as a whole. Therefore, the connection surfaces of the heat sinks 61 and 62 can be flat, and the heat sinks 61 and 62 can be easily provided.

In the present embodiment, the amplifying optical fiber 40, the winding portion 45, the side surface of the clad 42 is exposed to the plane FS _G parallel planar so as to form one of the board of the winding portion 45 , are formed planar exposed surface 46 further, the excitation fiber 30 at the winding portion 35, the side surface of the core 31 is exposed in the plane FS _P parallel planar one winding section 35 The planar exposed surface 36 is formed so as to form a board surface. However, the present invention is not limited thereto, and the exposed surface 46 and the plane FS _C is may not be parallel, and the exposed surface 46 and the plane FS _P may not be parallel.

(Second Embodiment)
Next, a second embodiment of the present invention will be described in detail with reference to FIGS. In addition, about the component which is the same as that of 1st Embodiment, or equivalent, except the case where it demonstrates especially, the same referential mark is attached | subjected and the overlapping description is abbreviate | omitted. FIG. 7 is a diagram showing a state of the structure in a cross section perpendicular to the longitudinal direction of the excitation fiber 30a according to the present embodiment, and FIG. 8 is a cross section perpendicular to the longitudinal direction of the amplification optical fiber 40a according to the present embodiment. FIG. 9 is a diagram showing the optical amplification component of this embodiment from the same viewpoint as FIG.

  The optical amplification component of the present embodiment uses a pumping fiber 30a instead of the pumping fiber 30 of the first embodiment, and uses an amplification optical fiber 40a instead of the amplification optical fiber 40 of the first embodiment. It differs from the optical amplification component of one embodiment.

  As shown in FIG. 7, the pump fiber 30a of this embodiment is different from the pump fiber 30 of the first embodiment in that a core 31 includes an inner core 31a and an outer core 31b surrounding the inner core 31a. The inner core 31a of the excitation fiber 30a is made of glass. As such glass, the same material as the core 31 of 1st Embodiment can be mentioned. The outer core 31b is made of a resin having a refractive index equivalent to that of the inner core 31a. Therefore, optically, the excitation fiber 30a of this embodiment and the excitation fiber 30 of 1st Embodiment are equivalent. Examples of the material of the outer core 31b include a silicon-based UV curable resin.

  As shown in FIG. 8, the amplification optical fiber 40a according to the present embodiment is the first embodiment in that the clad 42 includes an inner clad 42a surrounding the core 41 and an outer clad 42b surrounding the inner clad 42a. This is different from the amplification optical fiber 40 in the form. The inner clad 42a of the amplification optical fiber 40 is made of glass. Examples of such glass include the same material as that of the clad 42 of the first embodiment. The outer cladding 42b is made of a resin having a refractive index equivalent to that of the inner cladding 42a. Therefore, optically, the amplification optical fiber 40a of the present embodiment is the same as the amplification optical fiber 40 of the first embodiment. For this reason, the excitation light incident on the amplification optical fiber 40a mainly propagates through the clad 42 composed of the inner clad 42a and the outer clad 42b. Examples of the material of the outer cladding 42b include the same material as that of the outer core 31b of the excitation fiber 30a.

The amplification optical fiber 40a and the excitation fiber 30a are wound in the same manner as the amplification optical fiber 40 and the excitation fiber 30 in the first embodiment, and the low refractive index resin 58 is used in the same manner as in the first embodiment. Covered. Further, as shown in FIG. 9, in the amplification optical fiber 40a, the outer cladding 42b is exposed in a planar shape parallel to the plane FS _G in the winding portion 45, and a planar exposed surface 46 is formed. . Specifically, in a state where the amplification optical fiber 40 in a state where the cladding 42 is not exposed is wound in a spiral shape, a part of the resin cladding 43 and a part of the outer cladding 42b are connected to the inner cladding 42a. Is removed up to a plane that is exposed in a line (a plane parallel to the plane FS _G ). Similarly, the excitation fiber 30 at the winding portion 35, the outer core 31b may be exposed to parallel planar to the plane FS _P, planar exposed surface 36 is formed. Specifically, in a state where the excitation fiber 30 in a state where the core 31 is not exposed is wound in a spiral shape, a part of the cladding 32 and a part of the outer core 31b are linear in the inner core 31a. To a plane that is exposed to (a plane parallel to the plane FS _p ).

  And the exposed surface 46 of the optical fiber 40a for amplification and the exposed surface 36 of the excitation fiber 30a are connected like the optical amplification component 50 of 1st Embodiment.

  According to the optical amplification component 50 of the present embodiment, the resin constituting the outer cladding 42b of the amplification optical fiber 40a and the resin constituting the outer core 31b of the excitation fiber 30a can be easily cut or polished as compared with glass. Can be removed. Therefore, by having the outer cladding 42b and the outer core 31b made of resin, the cladding 42 and the core 31 of the amplification optical fiber 40a and the excitation fiber 30a can be easily exposed in a planar shape by cutting or polishing. Further, since the inner cladding 42a and the inner core 31a are made of glass, the loss of excitation light can be reduced.

(Third embodiment)
Next, a third embodiment of the present invention will be described in detail with reference to FIG. In addition, about the component which is the same as that of 1st Embodiment, or equivalent, except the case where it demonstrates especially, the same referential mark is attached | subjected and the overlapping description is abbreviate | omitted. FIG. 10 is a diagram showing the optical amplification component according to this embodiment from the same viewpoint as FIG.

  The optical amplification component of the present embodiment is different from the optical amplification component of the first embodiment in that a pump fiber 30b is used instead of the pump fiber 30 of the first embodiment.

Excitation fiber 30b of this embodiment is smaller in diameter than the excitation fiber 30 of the first embodiment, the excitation fiber 30b mutually adjoin without a gap, the central axis of the core on the plane FS _G parallel to the plane FS _P It is wound in a spiral shape so as to be positioned. In the present embodiment, the direction in which the excitation fiber 30b is wound is the same as the direction in which the amplification optical fiber 40 is wound, as in the first embodiment. Further, the excitation fiber 30b, as in the first embodiment, the winding portion, the side surface of the core is exposed to the plane FS _P parallel planar, planar exposed surface 36 is formed. The exposed surface 46 of the cladding of the amplification optical fiber 40 and the exposed surface 36 of the core of the excitation fiber 30b are connected to face each other.

  In the first embodiment, the amplification optical fiber 40 and the excitation fiber 30 are both wound at the same pitch with the same number of turns, and the amplification optical fiber 40 and the excitation fiber 30 are parallel to each other. In the embodiment, since the diameter of the excitation fiber 30b is small, it is not wound at the same pitch as that of the amplification optical fiber but is wound a different number of times. Therefore, in this embodiment, the amplification optical fiber 40 and the excitation fiber 30b are not parallel to each other.

  In such an optical amplification component, there may be a portion where the exposed surface 36 of the core of the excitation fiber 30 is not connected to the exposed surface 46 of the cladding of the amplification optical fiber 40, and the exposed surface of the cladding of the amplification optical fiber 40. There may be a portion where 46 is not connected to the exposed surface 36 of the core of the excitation fiber 30. However, as shown in FIG. 10, the excitation fiber 30b and the amplification optical fiber 40 are covered with a low refractive index resin 58 except for a portion where the core of the excitation fiber 30b and the cladding of the amplification optical fiber 40 are connected. Therefore, the exposed surface 36 of the pump fiber 30 exposed without facing the exposed surface 46 of the cladding of the amplification optical fiber 40 and the exposed surface 36 of the pump fiber 30 without facing the exposed surface 36 of the core. The excitation light is prevented from being emitted from the exposed surface 46 of the cladding of the amplification optical fiber 40.

  According to the optical amplification component of the present embodiment, the amplification optical fiber 40 and the excitation fiber 30b are non-parallel, so that the excitation light traveling along the excitation fiber 30b is incident on the amplification optical fiber 40. The traveling direction of the excitation light is disturbed. Therefore, the skew mode of the excitation light in the amplification optical fiber 40 can be suppressed.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described in detail with reference to FIG. In addition, about the component which is the same as that of 1st Embodiment, or equivalent, except the case where it demonstrates especially, the same referential mark is attached | subjected and the overlapping description is abbreviate | omitted. FIG. 11 is a view showing the optical amplification component according to this embodiment in the same manner as FIG.

  As shown in FIG. 11, the optical amplification component of this embodiment differs from the optical amplification component 50 of the first embodiment in that the pump fiber 30 and the amplification optical fiber 40 are wound in opposite directions. Specifically, the amplification optical fiber 40 and the excitation fiber 30 of this embodiment are wound in the direction indicated by the practical arrow in FIG. 11 from the inside to the outside, and this direction is the reverse direction. is there.

  According to the optical amplification component of the present embodiment, the amplification optical fiber 40 and the excitation fiber 30 can be reliably made non-parallel, and along the excitation fiber 30 as in the optical amplification component of the third embodiment. When the traveling pump light enters the amplification optical fiber 40, the traveling direction of the pump light is disturbed. Therefore, the skew mode of the excitation light in the amplification optical fiber 40 can be suppressed.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described in detail with reference to FIG. In addition, about the component which is the same as that of 1st Embodiment, or equivalent, except the case where it demonstrates especially, the same referential mark is attached | subjected and the overlapping description is abbreviate | omitted. FIG. 12 is a diagram showing the optical amplification component according to this embodiment from the same viewpoint as FIG.

As shown in FIG. 12, the optical amplification component of the present embodiment includes a pumping fiber similar to the pumping fiber 30 of the first embodiment as the second pumping fiber 30c, and the second pumping fiber 30c is the amplification optical fiber 40. And the excitation fiber 30 and a winding portion that is wound in the same direction at the same pitch and formed in a disk shape. That is, the second excitation fiber 30c is wound so that the central axis of the core is positioned on the plane FS _Pc . Further, the second excitation fiber 30c is positioned at the center axis of the core of the second excitation fiber 30c so that the side surface of the core forms one surface of the winding part of the second excitation fiber 30c. The exposed flat surface FS _Pc is exposed to a flat surface, and a flat exposed surface 36c is formed.

The clad 42 of the amplification optical fiber 40 of the present embodiment is a plane on which the central axis of the clad 42 is positioned so that the side surface opposite to the exposed surface 46 connected to the pump fiber 30 forms the other panel surface. exposed to FS _G parallel planar exposed surface 46c is formed.

  The exposed surface 46c opposite to the exposed surface 46 connected to the pumping fiber 30 in the cladding 42 of the amplification optical fiber 40 and the exposed surface 36c of the core of the second pumping fiber 30c are connected to face each other. Yes.

  In addition, a heat sink 61 connected to the amplification optical fiber 40 in the first embodiment is provided on the opposite side of the second excitation fiber 30c from the amplification optical fiber 40 side.

  According to the optical amplification component of the present embodiment, the amplification optical fiber 40 is sandwiched between the excitation fiber 30 and the second excitation fiber 30c, and a side pump can be realized by each of the excitation fiber 30 and the second excitation fiber 30c. . Therefore, stronger excitation light can be introduced into the amplification optical fiber 40, and the amplification factor of the seed light can be further increased.

In the present embodiment, the amplification optical fiber 40 has a winding portion 45 whose side opposite to the exposed surface 46 connected to the excitation fiber 30 is exposed in a planar shape parallel to the plane FS _G. A flat exposed surface 46c is formed so as to form the other disk surface of the turning portion 45, and the second excitation fiber 30c is a flat surface in which the side surface of the core is parallel to the plane FS _Pc in the winding portion. It is assumed that a flat exposed surface 36c is formed so as to be exposed in a shape and form one surface of the winding portion. However, the present invention is not limited thereto, the exposed surface 46c and the plane FS _C is may not be parallel, and the exposed surface 36c and the plane FS _P may not be parallel.

(Sixth embodiment)
Next, a sixth embodiment of the present invention will be described in detail with reference to FIG. In addition, about the component which is the same as that of 1st Embodiment, or an equivalent component, the overlapping description is abbreviate | omitted except the case where it attaches | subjects the same referential mark and demonstrates especially. FIG. 13 is a diagram showing the fiber laser device 2 according to the present embodiment.

  As shown in FIG. 13, the fiber laser device 2 of the present embodiment includes a first optical fiber amplifier 5 similar to the optical fiber amplifier 5 in the first embodiment and a first end coupled to one end of the amplification optical fiber 40. A resonance fiber 16; a second resonance fiber 18 coupled to the other end of the amplification optical fiber 40; a first FBG (Fiber Bragg Grating) 71 as a first mirror provided in the first resonance fiber 16; The second FBG 72 as a second mirror provided in the second resonance fiber 18 is provided as a main configuration.

  The first resonance fiber 16 has a core and a clad, and has, for example, the same configuration as the seed light fiber 15 in the first embodiment. The first resonance fiber 16 and the amplification optical fiber 40 are connected so that the core of the first resonance fiber 16 and the core 41 of the amplification optical fiber 40 are coupled. The first FBG 71 is provided in the core of the first resonance fiber 16, and the first FBG 71 is coupled to the core 41 of the amplification optical fiber 40. The first FBG 71 reflects light having the same wavelength as a part of the spontaneous emission light emitted when the active element added to the core 41 of the amplification optical fiber 40 is in an excited state, and the reflectance is For example, 100%.

  The second resonance fiber 18 has a core and a clad, and has the same configuration as the first resonance fiber 16, for example. The second resonance fiber 18 is connected to the amplification optical fiber 40, and the core 41 of the amplification optical fiber 40 and the core of the second resonance fiber 18 are coupled. A second FBG 72 is provided in the core of the second resonance fiber 18, and the second FBG 72 is coupled to the core 41 of the amplification optical fiber 40. The second FBG 72 reflects light having the same wavelength as the light reflected by the first FBG 71 with a lower reflectance than the first FBG 71. The reflectance of the second FBG is, for example, 30%.

  In such a fiber laser device 2, first, excitation light is emitted from each laser diode 21 of the excitation light source 20. As described above, the excitation light emitted from each laser diode 21 has a wavelength of, for example, 915 nm. Then, the pumping light emitted from each laser diode 21 propagates through the core of the pumping fiber 30 via each pumping port 22, and in the same manner as the optical amplification component 50 of the first embodiment, an amplification optical fiber. 40 is incident on the clad 42. The excitation light incident on the cladding of the amplification optical fiber 40 mainly propagates through the cladding 42. And when passing through the core 41, it is absorbed by the active element added to the core 41, and the active element is brought into an excited state.

  In this way, spontaneous emission light is emitted from the active element that has been excited by the excitation light, and light resonance occurs between the first FBG 71 and the second FBG 72 based on the spontaneous emission light. The resonating light has the same wavelength as the reflection wavelength of the first FBG 71 and the second FBG 72, and this resonating light is amplified by stimulated emission of the active element excited in the amplification optical fiber 40 as amplified light. A part of the amplified light passes through the second FBG 72 and is emitted as outgoing light. The light that passes through the first FBG 71 is converted into heat at the termination member 17.

  According to the fiber laser device 2 of this embodiment, since the optical amplification component 50 is excellent in heat dissipation, it can have excellent reliability.

  As mentioned above, although this invention was demonstrated to the 1st-6th embodiment as an example, this invention is not limited to these.

  For example, the amplification optical fiber 40, the excitation fibers 30, 30a, 30b, and the second excitation fiber 30c may be wound with a gap.

  In the first and second embodiments, the amplification optical fiber 40 and the excitation fiber 30 may be intentionally shifted so as to be non-parallel. Furthermore, in the second embodiment, the diameter of the pump fiber 30a may be different from the diameter of the amplification optical fiber 40a as in the third embodiment, and the pump fiber 30a as in the fourth embodiment. And the amplification optical fiber 40a may be wound in different directions. Furthermore, the pumping fiber 30 and the amplification optical fiber 40 of the first embodiment may be appropriately combined with the pumping fiber 30a and the amplification optical fiber 40a of the second embodiment.

  In the sixth embodiment, the optical amplification components of the second to fifth embodiments may be used.

  Further, the heat sinks 61 and 62 are not necessarily required, and at least one of the heat sinks may be omitted.

  In the above embodiment, the amplification optical fiber 40 and the excitation fiber 30 are wound in a disk shape, but may be wound in a disk shape so as to draw a substantially square shape.

  Hereinafter, the content of the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1
An optical amplification component similar to the optical amplification component of the second embodiment was produced. However, the heat sink was plate-like aluminum.

  First, a semi-manufactured optical fiber for amplification composed of a core to which ytterbium (Yb) was added and an inner clad made of quartz to which no dopant was particularly added was produced. The core diameter was 10 μm and the inner cladding diameter was 300 μm. And the outer peripheral surface of the inner cladding was coated with a silicone resin having a thickness of 30 μm to form an outer cladding. The refractive indexes of the inner cladding and the outer cladding were both 1.458. Further, the outer peripheral surface of the outer clad was covered with a resin clad having a refractive index lower than that of the inner clad and the outer clad to obtain an amplification optical fiber. For the resin cladding, a resin having a refractive index of 1.380 was used, and the thickness of the resin cladding was 50 μm.

  Next, an inner core having the same diameter and the same material as the inner cladding of the amplification optical fiber, an outer core having the same outer diameter and the same material as the outer cladding of the amplification optical fiber, and the amplification An excitation fiber made of a clad having the same outer diameter and the same material as the resin clad of the optical fiber was produced.

  Next, the amplification optical fiber was wound into a disk shape over a length of 30 m. At this time, the optical fiber for amplification was wound so that the minimum diameter was 200 mm and the amplification optical fibers were in contact with each other. Similarly, the excitation fiber was wound into a disk shape over 30 m. At this time, it was wound so that the minimum diameter was 200 mm and the excitation fibers were in contact with each other. In each winding of the amplification optical fiber and the excitation fiber, the amplification optical fiber and the excitation fiber were wound so as to be sandwiched between the aluminum plate and the quartz plate, respectively.

  Next, the wound portions of the amplification optical fiber and the excitation fiber in a wound state are covered with a fluorinated acrylic resin as a low refractive index resin having a refractive index of 1.380 and a Shore hardness of 25, and fluorinated. The acrylic resin was cured. Specifically, using an ultraviolet curable fluorinated acrylic resin, between the aluminum plate and the quartz plate sandwiching the amplification optical fiber, and between the aluminum plate and the quartz plate sandwiching the excitation fiber In the meantime, the resin was impregnated and irradiated with ultraviolet rays from the quartz plate side to cure the resin. Thereafter, only the quartz plate was peeled off, and the aluminum plate was used as it was as a heat sink.

  Next, the surface of the amplification optical fiber from which the quartz plate has been peeled is polished to remove the low refractive index resin, resin cladding, and outer cladding until the inner cladding is slightly exposed, and the outer cladding is exposed in a planar shape. It was in a state to do. At this time, the width of the exposed surface of the outer cladding was 200 μm. Similarly, the surface of the excitation fiber from which the quartz plate has been peeled is polished, and the low refractive index resin, the clad, and the outer core are removed until the inner core is slightly exposed, so that the outer core is exposed in a planar shape. . At this time, the width of the exposed surface of the outer core was 200 μm.

  Then, a resin having a refractive index of 1.458 was connected so that the exposed surface of the cladding of the amplification optical fiber and the exposed surface of the core of the excitation fiber coincided.

  Thus, an optical amplification component was obtained.

  Next, FBGs are provided at both ends of the amplification optical fiber so that one FBG has approximately 100% signal light reflectivity and the other FBG has approximately 10% signal light reflectivity. .

  Also, a pump combiner of 1 × 19 ports is connected to both ends of the pump fiber, and the core of 19 pump ports made of a fiber having a core diameter of 105 μm and a glass cladding diameter of 125 μm is coupled with the core of the pump fiber. It was.

  Then, excitation light having a wavelength of 915 nm and an intensity of 8 W was incident on the core of each excitation port. Therefore, the excitation light incident on the excitation fiber is about 300 W. At this time, resonance occurred, and the emitted light had a wavelength of 1080 nm and an intensity of 190 W. A high amplification rate exceeding 60% was achieved.

  At this time, the temperature of the optical amplification component was as low as 47 ° C. Therefore, it was found that the optical amplification component of the present invention is excellent in heat dissipation.

  As described above, according to the present invention, an optical amplifying component having excellent heat dissipation, and an optical fiber amplifier and a fiber laser device using the same are provided.

DESCRIPTION OF SYMBOLS 1, 2 ... Fiber laser apparatus 5 ... Optical fiber amplifier 10 ... Seed light source 15 ... Seed light fiber 16 ... 1st resonance fiber 18 ... 2nd resonance fiber 20 ..Excitation light source 21 ... Laser diode 22 ... Excitation port 23 ... Combiner 30, 30a, 30b, 30c ... Excitation fiber 31 ... Core 31a ... Inner core 31b ... Outer core 32 ... clad 35 ... winding part 36, 36c ... exposed surface 40, 40a ... optical fiber for amplification 41 ... core 42 ... clad 42a ... inner clad 42b ... External clad 43 ... Resin clad 45 ... Winding part 46, 46c ... Exposed surface 50 ... Optical amplification component 58 ... Low refractive index resin 61, 62 ... Heat sink 71 ... First FBG (first mirror)
71 ... 2nd FBG (2nd mirror)
FS _G , FS _P , FS _Pc ... plane

Claims (12)

An amplification optical fiber having a core to which an active element is added, and a cladding that propagates excitation light that excites the active element;
A pump fiber having a core for propagating the pump light;
With
The amplification optical fiber has a disk-shaped winding portion wound in a spiral shape so that the central axis of the cladding is positioned on a plane, and in the winding portion of the amplification optical fiber, The side surface of the clad is exposed in a flat shape so as to form one board surface,
The excitation fiber has a disk-shaped winding portion wound in a spiral shape so that the central axis of the core is positioned on a plane, and the side surface of the core is in the winding portion of the excitation fiber. , Exposed in a flat shape to form one board surface,
The optical amplification component, wherein the exposed surface of the cladding of the optical fiber for amplification and the exposed surface of the core of the excitation fiber are connected to face each other.   The optical amplification component according to claim 1, wherein the amplification optical fiber and the excitation fiber are wound non-parallel to each other.   The optical amplification component according to claim 2, wherein the amplification optical fiber and the excitation fiber are wound in opposite directions.   The optical amplification component according to claim 1, wherein the amplification optical fiber and the excitation fiber are wound in parallel with each other. The clad of the optical fiber for amplification surrounds the core to which the active element is added, and includes an inner clad made of glass, and an outer clad that surrounds the inner clad and is made of a resin having a refractive index equivalent to that of the inner clad. And consists of
5. The optical amplification component according to claim 1, wherein a part of the outer cladding is exposed in a planar shape. The core of the excitation fiber includes an inner core made of glass, and an outer core that surrounds the inner core and is made of a resin having a refractive index equivalent to that of the inner core.
The optical amplification component according to any one of claims 1 to 5, wherein a part of the outer core is exposed in a planar shape.   The winding portion of the amplification optical fiber and the winding portion of the excitation fiber are the excitation except for a portion where the core of the excitation fiber and the cladding of the amplification optical fiber are connected. The optical amplification component according to claim 1, wherein the optical amplification component is covered with a low refractive index resin having a refractive index lower than that of the core of the fiber and the cladding of the amplification optical fiber. The at least one of the side opposite to the exposed surface of the excitation fiber and the side opposite to the exposed surface of the amplification optical fiber is connected to a heat sink. An optical amplification component as described in 1. A pumping fiber similar to the pumping fiber is further provided as a second pumping fiber,
The second pumping fiber has a disk-shaped winding part wound in a spiral shape so that a central axis of the core is positioned on a plane, and the core of the second pumping fiber includes the core The side surface of is exposed in a flat shape so as to form one board surface,
The amplification optical fiber is exposed in a planar shape so that a side surface opposite to the exposed surface connected to the excitation fiber forms the other panel surface,
An exposed surface of the cladding of the amplification optical fiber opposite to the exposed surface connected to the pump fiber and an exposed surface of the core of the second pump fiber are connected to face each other. The optical amplification component according to any one of claims 1 to 7. The optical amplification component according to any one of claims 1 to 8,
An excitation light source that emits the excitation light incident on the core of the excitation fiber;
An optical fiber amplifier comprising: The optical amplification component according to any one of claims 1 to 8,
A seed light source for emitting seed light incident on the core of the amplification optical fiber;
An excitation light source that emits the excitation light incident on the core of the excitation fiber;
A fiber laser device comprising: The optical amplification component according to any one of claims 1 to 8,
An excitation light source that emits the excitation light incident on the core of the excitation fiber;
A mirror that is provided on one end of the amplification optical fiber and reflects at least part of the light emitted by the active element excited by the excitation light;
A second mirror that is provided on the other end of the amplification optical fiber and reflects light reflected by the first mirror with a lower reflectance than the first mirror;
A fiber laser device comprising:

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