JP5308175B2 - Optical fiber cooling equipment - Google Patents

Description

  The present invention relates to an optical fiber cooling apparatus capable of effectively cooling an end portion of an optical fiber cable that is likely to generate heat when using an optical fiber laser apparatus that oscillates and amplifies laser light using an optical fiber cable.

  Many laser apparatuses using optical fiber cables as laser light media, so-called optical fiber laser apparatuses, have been developed. An optical fiber laser device oscillates or amplifies laser light by entering pumping light from a pumping light source such as a semiconductor laser into a laser medium such as a rare earth ion added to the core of an optical fiber cable. Device.

  Like ordinary solid-state lasers, reflection mirrors and output mirrors are arranged at both ends of the optical fiber cable. Between each mirror and the end face of the optical fiber cable, light from the mirror is sent to the optical fiber cable. A lens for reliably guiding the lens is disposed inside.

  By the way, in the optical fiber laser device, the temperature of the optical fiber cable rises due to the oscillation of the laser light, etc. Especially, the end face of the optical fiber cable tends to generate heat, and there is a high possibility that thermal damage will occur. Therefore, how to cool the optical fiber cable is one of the important issues for exhibiting stable laser characteristics, amplification characteristics, and the like.

  In order to solve such a problem, for example, Patent Document 1 discloses an optical fiber heat dissipation device that holds an optical fiber wound around a highly thermally conductive metal plate filled with a thermal conductive grease. ing. By covering the optical fiber with a material having high thermal conductivity, simple temperature control can be performed so that the optical fiber becomes constant near room temperature.

  On the other hand, Patent Document 2 discloses an optical fiber heat dissipation device in which the inside of a metal housing in which an optical fiber is disposed is filled with a hydrophobic liquid or resin. The optical fiber is immersed in a hydrophobic liquid or resin together with the optical connector, so that moisture resistance can be improved and simple temperature control can be performed.

JP 2001-274489 A JP 2004-214325 A

  However, in Patent Document 1, the end face of an optical fiber cable that easily generates heat is not covered with grease, and the possibility of thermal damage cannot be reduced. On the other hand, in Patent Document 2, the possibility of thermal damage can be reduced by immersing the end face of an optical fiber cable that easily generates heat into a hydrophobic liquid or resin together with the connector. However, since the end face of the optical fiber cable is covered with a connector, and the filled hydrophobic liquid or resin has no means for generating a flow other than thermal convection, the end face of the optical fiber cable generates heat. However, when the temperature of the connector, the hydrophobic liquid, or the resin is increased, the heat radiation effect is reduced, and the temperature control of the end face of the optical fiber cable becomes difficult.

  This invention is made | formed in view of such a situation, and it aims at providing the optical fiber cooling device which can suppress the heat_generation | fever of the end surface of an optical fiber cable effectively.

In order to achieve the above object, an optical fiber cooling apparatus according to a first aspect of the present invention includes an optical fiber cable that includes a refrigerant tank filled with a refrigerant and an optical fiber cable immersed in the refrigerant, and cools the optical fiber cable. The first optical fiber cable includes a first fiber support portion and a second fiber support portion that support both ends of the optical fiber cable. One end of the optical fiber cable is brought into close contact with the first window plate at the first fiber support portion that supports one end of the cable, and a second window plate is provided at a light output portion of the refrigerant tank, and the optical fiber The other end of the optical fiber cable is brought into close contact with the second window plate at the second fiber support portion supporting the other end of the cable, and the one end and the other end of the optical fiber cable are substantially hemispherical. Cage, wherein the first fiber support portion and the second fiber support portion is provided with a crimping portion for crimping the one end and the other end of the optical fiber cable to each of the first aperture plate and the second window pane The optical fiber cable has a core and a clad, and one end and the other end of the optical fiber cable are crimped to the first window plate and the second window plate, respectively, and one end of the optical fiber cable and clad of the other end is characterized that you have been covered with the refrigerant.

  In the first invention, it has a first fiber support portion and a second fiber support portion that support both ends of the optical fiber cable, and a first window plate is provided in the incident light incident portion of the refrigerant tank, A second window plate is provided at the light exit portion. One end of the optical fiber cable is brought into close contact with the first window plate at the first fiber support portion that supports one end of the optical fiber cable, and the optical fiber at the second fiber support portion that supports the other end of the optical fiber cable. The other end of the cable is in close contact with the second window plate. One end and the other end of the optical fiber cable are substantially hemispherical, and the first fiber support portion and the second fiber support portion are connected to the first window plate and the second fiber support portion, respectively. A crimping part for crimping the second window plate is provided. Since the entire optical fiber cable including the end portion is immersed in the refrigerant tank, heat generation of the optical fiber cable due to laser light oscillation or the like can be suppressed. In addition, since the end of the optical fiber cable has a substantially hemispherical shape, even if it is pressure-bonded to the window plate, the refrigerant penetrates to the immediate vicinity of the end surface and the indirect cooling effect through the window plate. Therefore, heat generation at the end face of the optical fiber cable can be effectively suppressed.

  The optical fiber cooling device according to a second aspect of the present invention is the optical fiber cooling device according to the first aspect, wherein the refrigerant tank is configured to supply a refrigerant to the vicinity of one end and the other end of the optical fiber cable, one end of the optical fiber cable, And a recovery path for recovering the refrigerant supplied to the opposite side to the other end.

  In the second invention, the refrigerant tank includes a supply path for supplying the refrigerant to the vicinity of one end and the other end of the optical fiber cable, and a recovery path for recovering the refrigerant supplied to the side opposite to the one end and the other end of the optical fiber cable. The refrigerant flows from the supply path to the recovery path and moves inside the refrigerant tank. Therefore, when the refrigerant becomes warm due to absorption of heat, the temperature in the refrigerant tank can be maintained at a low temperature by cooling the refrigerant again by, for example, a chiller provided outside and flowing it into the refrigerant tank. The cooling effect of the optical fiber cable and its end face can be enhanced.

  In the optical fiber cooling device according to a third aspect of the present invention, in the first or second aspect, the supply path is formed in a direction in which the refrigerant is directly supplied to one end and the other end of the optical fiber cable. It is characterized by that.

  In the third invention, the supply path is formed in a direction in which the refrigerant is directly supplied to one end and the other end of the optical fiber cable, so that the refrigerant cooled by an external chiller or the like has a high degree of heat generation. It can be poured directly into the end of the optical fiber cable, and the cooling effect can be further enhanced.

  With the above configuration, since the entire optical fiber cable including the end portion is immersed in the refrigerant tank, heat generation of the optical fiber cable due to laser light oscillation or the like can be suppressed. In addition, since the end of the optical fiber cable has a substantially hemispherical shape, even if it is pressure-bonded to the window plate, the refrigerant penetrates to the immediate vicinity of the end surface and the indirect cooling effect through the window plate. Therefore, heat generation at the end face of the optical fiber cable can be effectively suppressed.

It is a plane schematic diagram which shows the structure of the optical fiber cooling device which concerns on embodiment of this invention. It is sectional drawing and the perspective view in the surface orthogonal to the longitudinal direction of an optical fiber cable. It is the fragmentary top view and AA sectional view which show the structure of the holder of the optical fiber cooling device which concerns on embodiment of this invention. It is sectional drawing in the surface orthogonal to the longitudinal direction of the optical fiber cable which shows the relationship between the end surface of an optical fiber cable, and a window board. It is a fragmentary top view which shows the structure of the supply path of the optical fiber cooling device which concerns on other embodiment of this invention.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof. FIG. 1 is a schematic plan view showing a configuration of an optical fiber cooling device according to an embodiment of the present invention.

  As shown in FIG. 1, an optical fiber cooling device 1 according to an embodiment of the present invention includes a cylindrical bobbin (tubular body) 11 inside a refrigerant tank 2. The bobbin 11 is preferably made of a material having high thermal conductivity such as aluminum or copper. This is because the cooling effect of the optical fiber cable 12 wound around the peripheral wall portion of the bobbin 11 is enhanced. The refrigerant tank 2 is filled with a refrigerant. As the refrigerant, a hydrophobic fluid such as fluorinate is used in order to prevent deterioration of the optical fiber cable due to moisture.

  An optical fiber cable 12 is wound around the peripheral wall portion of the bobbin 11, and holders (support portions) 13 and 14 for supporting the optical fiber cable 12 are disposed at both ends of the optical fiber cable 12. The holder 13 is a holder (first fiber support portion) on the excitation side of the optical fiber cable 12, and the end face of the optical fiber cable 12 is crimped to the first window plate 3. Excitation light emitted from the excitation light source 131 is aggregated via the lenses 132 and 133 and is aggregated to the excitation-side end portion of the optical fiber cable 12 via the first window plate 3.

  The holder 14 is a holder (second fiber support portion) on the terminal end side of the optical fiber cable 12, and presses the end face of the optical fiber cable 12 to the first window plate 3. The laser light emitted from the terminal side of the optical fiber cable 12 enters the lens 141 through the second window plate 4, is totally reflected by the mirror 142, is collected by the lens 141, and is again collected by the second window. It returns from the terminal end side of the optical fiber cable 12 to the excitation side via the plate 4. The laser beam reflected by the terminal-side mirror 142 passes through the optical fiber cable 12, enters the lens 133 through the first window plate 3, and is guided to the dichroic mirror 134.

  The dichroic mirror 134 transmits the excitation light from the excitation light source 131, but reflects the laser light reflected by the mirror 142 on the end side of the optical fiber cable 12 without transmitting. The laser beam reflected by the dichroic mirror 134 is used as an output for various purposes.

  FIG. 2 is a cross-sectional view and a perspective view of a plane orthogonal to the longitudinal direction of the optical fiber cable 12. As shown in FIGS. 2A and 2B, the optical fiber cable 12 is composed of a core 121 and a clad 122. In the core 121, a laser medium such as rare earth ions is added. The laser medium added to the core 121 is excited by excitation light emitted from the excitation light source 131 and outputs laser light. The number of excitation light sources 131 may be adjusted according to the level of laser light to be output.

  Returning to FIG. 1, guide paths 15 and 16 for inserting the holders 13 and 14 to guide the optical fiber cable 12 to the first window plate 3 or the second window plate 4 are formed in the refrigerant tank 2. The end face of the optical fiber cable 12 is crimped to the first window plate 3 or the second window plate 4. That is, the holders 13 and 14 function as a crimping part. FIG. 3 is a partial plan view and AA cross-sectional view showing the configuration of the holder 13 (14) of the optical fiber cooling device 1 according to the embodiment of the present invention. Fig.3 (a) is a fragmentary top view which shows the structure of the holder 13 of the optical fiber cooling device 1 which concerns on this Embodiment, FIG.3 (b) is AA cross section of the holder 13 shown to Fig.3 (a). FIG. What is necessary is just to think that the holder 14 turns right and left toward drawing.

  As shown in FIG. 3 (a), the holder 13 has the optical fiber cable 12 passing through the center, and the first holder 135, the second holder 136, and the first holder 135 and the second holder 136. It is comprised with the biasing member (spring) 137 clamped. The vicinity of the end of the optical fiber cable 12 is fixed by screwing with a fiber holder 1351 and a fiber holder 1352 of the first holder 135. The holding member 1353 of the first holder 135 is screwed to the refrigerant tank 2 so that the fiber holder 1351 can slide in the longitudinal direction of the optical fiber cable 12. On the other hand, the pressing member 1362 of the second holder 136 is fixed by screwing the fiber holder 1361 to the refrigerant tank 2, but the optical fiber cable 12 can be slid in the longitudinal direction and fixed. Not.

  Therefore, the fiber holder 1351 is urged toward the first window plate 3 by the urging force of the urging member (spring) 137, and the end face of the optical fiber cable 12 is in close contact with the first window plate 3. FIG. 4 is a cross-sectional view taken along a plane orthogonal to the longitudinal direction of the optical fiber cable 12 showing the relationship between the end face of the optical fiber cable 12 and the first window plate 3.

  As shown in FIG. 4, the end surface of the optical fiber cable 12 has a substantially spherical shape, and only the core 121 is in contact with the first window plate 3. Therefore, since the coolant is supplied to cover the clad 122 around the core 121, the end portion of the optical fiber cable 12 having a particularly high degree of heat generation can be cooled more effectively. The relationship between the end face of the optical fiber cable 12 and the second window plate 4 is the same.

  Returning to FIG. 1, supply paths 17 and 18 for supplying a refrigerant are connected to the guide paths 15 and 16, respectively, and on the opposite surface of the refrigerant tank 2 where the guide paths 15 and 16 are provided. A recovery path 19 for recovering the refrigerant is provided. The refrigerant that has become warm by absorbing the heat generated by the end face of the optical fiber cable 12 is sucked through the refrigerant path 20 by the pump 22, cooled by the chiller 21, and again passes through the refrigerant path 20 as a low-temperature refrigerant. To the supply paths 17 and 18.

  Since the opening part to the inside of the refrigerant tank 2 of the supply paths 17 and 18 is in the vicinity of the end part of the optical fiber cable 12, the refrigerant cooled by the chiller 21 flows directly into the end part of the optical fiber cable 12. The cooling effect can be enhanced. Moreover, since the flow of the refrigerant is generated inside the refrigerant tank 2, the refrigerant that has absorbed the heat does not stay in the refrigerant tank 2, and the heat absorption efficiency can be further increased.

  The supply paths 17 and 18 are not limited to being linear channels substantially orthogonal to the guide paths 15 and 16. FIG. 5 is a partial plan view showing the configuration of the supply path 17 (18) of the optical fiber cooling device 1 according to another embodiment of the present invention. It can be considered that the supply path 18 is reversed left and right as viewed in the drawing.

  As shown in FIG. 5, it is preferable that the opening portion of the supply path 17 into the refrigerant tank 2 is as close as possible to the end portion of the optical fiber cable 12, that is, the portion that contacts the first window plate 3. The supply path 17 may be inclined so that the opening of the supply path 17 into the refrigerant tank 2 contacts the first window plate 3. Further, the supply path 17 may be formed so as to curve toward the first window plate 3 in the refrigerant tank 2, and toward the direction in which the refrigerant is directly supplied to the end of the optical fiber cable 12. It is sufficient if it is formed. Thereby, the refrigerant cooled by the external chiller 21 or the like can be directly poured into the end portion of the optical fiber cable 12 having a high degree of heat generation, and the cooling effect can be further enhanced.

  As described above, according to the present embodiment, since the entire optical fiber cable 12 including the end portion is immersed in the refrigerant tank 2, the heat generation of the optical fiber cable 12 due to laser light oscillation or the like. Can be suppressed. In addition, since the end portion of the optical fiber cable 12 has a substantially hemispherical shape, even when it is pressure-bonded to the first window plate 3 or the second window plate 4, the refrigerant is in the immediate vicinity of the end surface. And the indirect cooling effect through the first window plate 3 or the second window plate 4 can be expected, and the heat generation at the end face of the optical fiber cable 12 can be effectively suppressed.

  In the present embodiment, an optical fiber laser oscillator using the optical fiber cable 12 is described as an example. However, the present invention is not particularly limited to this, and for example, the optical fiber cable 12 is used. Even when applied to a laser operating device, such as an optical fiber laser amplifier, the same effect can be obtained.

  In addition, it goes without saying that various modifications and replacements are possible within the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Optical fiber cooling device 3 1st window board 4 2nd window board 11 Bobbin (cylinder)
12 Optical fiber cable 13 Holder (first fiber support part, crimping part)
14 Holder (second fiber support, crimping part)
17, 18 Supply path 19 Collection path

Claims (3)

A refrigerant tank filled with refrigerant;
An optical fiber cooling device for cooling an optical fiber cable, comprising: an optical fiber cable immersed in a refrigerant;
A first fiber support and a second fiber support for supporting both ends of the optical fiber cable;
A first window plate is provided at an incident light incident portion of the refrigerant tank, and one end of the optical fiber cable is connected to the first window plate by the first fiber support portion that supports one end of the optical fiber cable. Closely
A second window plate is provided at the light exit portion of the refrigerant tank, and the other end of the optical fiber cable is in close contact with the second window plate at the second fiber support portion that supports the other end of the optical fiber cable. Let
One end and the other end of the optical fiber cable have a substantially hemispherical shape, and the first fiber support portion and the second fiber support portion respectively connect the one end and the other end of the optical fiber cable to the first end. A crimping part for crimping to the window plate and the second window plate ,
The optical fiber cable has a core and a clad, and one end and the other end of the optical fiber cable are crimped to the first window plate and the second window plate, respectively, optical fiber cooling device clad end is characterized that you have been covered with the refrigerant.
  The refrigerant tank includes a supply path for supplying a refrigerant to the vicinity of one end and the other end of the optical fiber cable, and a recovery path for recovering the refrigerant supplied to the opposite side of the one end and the other end of the optical fiber cable. The optical fiber cooling device according to claim 1.   The optical fiber cooling device according to claim 1, wherein the supply path is formed in a direction in which a coolant is directly supplied to one end and the other end of the optical fiber cable.

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