JP2005249861A - Optical fiber sensor and optical fiber sensor module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical fiber sensor and an optical fiber sensor module with which the variation in a measured part is accurately measured while keeping a high breaking durability. <P>SOLUTION: In the optical fiber sensor 1, a three-layer metal film is used as a protection film of an optical fiber 2 provided with a sensor main body 6 at a part in the longitudinal direction, an FBG 7 formed at a core 3 located at the sensor main body 6 is formed with strength or maximum reflectance in which a loss happening in a process of forming the metallic film due to film making temperature is taken into consideration. Thus, mounting of the optical fiber sensor on the measured part is simplified and easily handled. Further, the optical fiber sensor module 10 is so formed that supporting members 11a and 11b arranged in a pair interposing the sensor main body 6 on the optical fiber sensor 1 are fixed on the optical sensor via a fixing member 12. Thus, a high resistance against an environment having high temperature and high humidity and the high breaking durability are given to the optical fiber sensor 1 while keeping a high physical sensitive performance. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical fiber sensor and an optical fiber sensor module.

Currently, technological development of an optical fiber sensor that uses an optical fiber widely used in the field of communication as a sensor for detecting physical quantities such as strain and temperature is in progress. Among optical fiber sensors, the FBG method can measure a physical quantity with high accuracy and high speed, and a plurality of sensors can be arranged on one optical fiber.
These FBG type optical fiber sensors use an ultraviolet laser to create a FBG having a different refractive index for a core located in a part of the length direction of the optical fiber to form a sensor body. The change in refractive index is the detection principle of the sensor.

  When these FBG type optical fiber sensors are used, it is necessary to fix them to a measurement site of an object to be measured using an optical adhesive or the like. However, since the optical fiber itself was originally manufactured for communication, not only is it inferior in resistance to high temperature and high humidity environments, but the optical fiber is easily distorted by fixing with an optical adhesive, Since the optical adhesive functions as a buffer material against disturbances such as physical changes in the measurement site, it has been difficult to accurately measure the amount of change in the measurement site.

Under such circumstances, as a configuration suitable for use in a high-temperature / high-humidity environment or when high accuracy and reliability are required, as shown in Patent Document 1, a protective coating that constitutes an optical fiber is coated with a metal by plating. A so-called metallized fiber using a coating has been devised.
Japanese Patent Laid-Open No. 2002-116094 (see FIG. 2)

  These metallized fibers can be transmitted to the clad and core as they are without relaxing the stress applied from the outside because the metal film by plating is extremely thin, even though it is hard, and can be applied to optical fiber sensors. A configuration capable of detecting a physical quantity with high accuracy can be obtained. In addition, since the outer peripheral surface is coated with a metal film by plating, welding or soldering can be used instead of optical adhesive for fixing to the measurement site, so static or dynamic measurement of optical fiber sensors Accuracy can be improved.

  However, the structure using the metal film by the plating method as the protective film constituting the optical fiber sensor is because the metal film by the plating method is extremely thin as described above, so welding or soldering was used for the fixing member. In some cases, when a phenomenon such as a sharp irregularity (surface structure with a small radius of curvature) on the surface or a tension including a component perpendicular to the axial direction of the optical fiber sensor occurs, the optical fiber sensor easily Stress concentration, and the optical fiber sensor is likely to break.

  In addition, if the metal film is formed by a sputtering method that is generally known as a method capable of obtaining high adhesion strength instead of the plating method, the optical fiber sensor is exposed to a high temperature environment. The formed FBG is likely to be lost.

  In view of the above circumstances, an object of the present invention is to provide an optical fiber sensor and an optical fiber sensor module that can accurately measure the amount of change in a measurement site while ensuring high fracture durability.

  The optical fiber sensor according to claim 1, wherein a sensor main body for detecting a physical quantity of an object to be measured is formed in at least a part of a length direction of an optical sensor including a core, a clad covering the core, and a protective film covering the clad. An optical fiber sensor, wherein the sensor body is formed by forming a fiber Bragg grating (hereinafter referred to as FBG) on the core, and the protective film is formed by a metal film formed by sputtering. The FBG is formed to have a strength or maximum reflectivity that takes into account the amount of loss due to the deposition temperature when the cladding is coated with the protective coating.

  The optical fiber sensor module according to claim 2 is made of a metal material, and a support member disposed in a pair so as to sandwich a sensor body of the optical fiber sensor is interposed between the optical fiber sensor and a fixing member. It is characterized by being fixed.

  The optical fiber sensor module according to claim 3, wherein solder or weld metal is used for a fixing member that fixes the optical fiber sensor and the support member, and the fixing member is positioned in a length direction of the optical fiber sensor. The end portion is provided with a buffer material.

  The optical fiber sensor module according to claim 4, wherein the fixing member extends in the length direction of the optical fiber sensor, and the fixing strength of the fixing member is positioned in the length direction of the optical fiber sensor. It is characterized by continuously increasing from the center to the center.

  According to the optical fiber sensor of claim 1, the FBG having the strength or the maximum reflectivity in which the loss amount due to the film forming temperature when the clad is coated with the protective film is previously added to the core located in the sensor body is formed. Therefore, even if a metal film is applied to the protective film and this is coated on the clad using a sputtering method in which the film forming temperature is high, the physical quantity detection performance of the sensor body does not deteriorate. An optical fiber sensor having resistance to the environment can be formed.

  In addition, by using a metal film formed by sputtering as the protective film, the optical fiber sensor is not subject to distortion even if an external force such as tension or bending acts on the optical fiber sensor due to any factor. It becomes possible to provide a physical quantity detection performance with strong and high accuracy and reliability.

In addition, by using a metal film by sputtering as the protective film, a hard fixing member such as solder or weld metal that may have sharp irregularities on the surface is used to fix the optical fiber sensor to the measurement site. However, the phenomenon that the optical fiber sensor breaks can be suppressed.
In this way, since a hard fixing member such as solder or weld metal can be used for fixing the optical fiber sensor to the measurement site, the fixing member does not function as a buffer material like an optical adhesive. Thus, it is possible to accurately measure the amount of change in the measurement site.

According to the optical fiber sensor module according to claim 2, since the pair of support members made of a metal material are fixed to the optical fiber sensor, the optical fiber sensor can be fixed to the measurement site via the support member. The mounting configuration of the optical fiber sensor to the measurement site is simplified, and the handling of the optical fiber sensor can be facilitated.
In addition, since the optical fiber sensor is not directly touched when attaching to the measurement site, the external force accompanying the installation work is not applied to the optical fiber sensor, so that the optical fiber sensor can be accurately applied to the measurement site while protecting the sensor body. Can be arranged.

  By adding a conversion mechanism to such an optical fiber sensor module, it is possible to use an optical fiber sensor that primarily measures strain, temperature, etc. for various measurements such as acceleration and displacement. Measurement modules such as a meter, a thermometer, an accelerometer, and a displacement meter can be formed.

  According to the optical fiber sensor module of claim 3, since solder or weld metal is used for the fixing member for fixing the optical fiber sensor and the supporting member, the supporting member and the fixing member interposed between the measurement site and the sensor body are fixed. Since there is no flexible member that can be a buffer material in any of the members, it is possible to accurately detect the amount of change in the measurement site.

  In addition, since the buffer member is provided at the end of the fixing member in the longitudinal direction of the optical fiber sensor, the longitudinal direction of the optical fiber sensor can be applied even when a tension including a component perpendicular to the axial direction acts on the optical fiber sensor. Since deformation with a small curvature radius that is likely to occur in the vicinity of the end portion of the fixing member positioned in the direction can be prevented and stress concentration can be relaxed, phenomena such as fracture can be suppressed.

  According to the optical fiber sensor module of claim 4, the fixing member is extended in a band shape in the longitudinal direction of the optical fiber sensor, and the fixing strength is extended from the end in the longitudinal direction of the optical fiber sensor toward the center. Therefore, even if a tension including a component perpendicular to the axial direction is applied to the optical fiber sensor, the deformation of the optical fiber sensor is distributed over a wide range in the length direction of the fixing member and stress is applied. Since concentration can be relaxed, it is possible to suppress phenomena such as breakage.

  The optical fiber sensor and optical fiber sensor module of the present invention are shown in FIGS. The present invention uses a metal film by sputtering for a protective film of an optical fiber provided with a sensor body in a part in the length direction, and forms an FBG formed on a core located in the sensor body at the time of forming the metal film. By configuring the strength or maximum reflectivity in consideration of the loss amount due to temperature in advance, the optical fiber sensor is provided with high resistance to high temperature / high humidity environments and fracture resistance while maintaining physical detection performance. By fixing the support member to the optical fiber sensor to form an optical fiber sensor module, the mounting of the optical fiber sensor to the measurement site is simplified and the handling is facilitated.

  As shown in the longitudinal sectional view of FIG. 1A, the optical fiber sensor 1 has a configuration in which a sensor main body 6 is formed in a part of the length direction of the optical fiber 2. 1 (b), a core 3 through which light passes, a clad 4 having a refractive index lower than that of the core 3 and disposed so as to cover the outer peripheral surface of the core 3, and the clad 4 It is comprised by the protective film 5 arrange | positioned so that it may cover.

In addition, as shown in FIG. 1A, the sensor body 6 is formed in the optical fiber 2 by forming a periodic refractive index structure called FBG 7 in the core 3 constituting the optical fiber 2 using an ultraviolet laser. Reflects light of a specific wavelength that is determined by the periodic interval depending on the tensile or compressive stress acting or changes in ambient temperature and the effective refractive index of the propagating light. It functions as a sensor for detecting a physical change such as a sensor or a temperature sensor.
In the optical fiber sensor 1 according to the present embodiment, the sensor body 6 is formed only on a part of the optical fiber 2, but this is not necessarily the case, and the sensor body 6 is disposed in the length direction of the optical fiber 2. A plurality of structures may be formed.

  By the way, a metal film is used for the protective film 5 constituting the optical fiber 2, and as shown in FIG. 1A, the titanium layer 5a, the nickel layer 5b, and the gold layer are formed from the inner layer toward the outer layer. 5c has three layers. These coat the outer peripheral surface of the clad 4 using a sputtering method generally known as a method capable of obtaining a high adhesion strength as compared with a plating method among metal coating methods.

  However, when the protective film 5 made of a metal film is formed by sputtering, a high temperature environment is necessary, and such a high temperature environment is one of the FBGs 7 formed on the core 3 located in the sensor body 6. As a result, the physical detection performance originally provided in the sensor main body 6 is likely to deteriorate. For this reason, the loss amount of the FBG 7 assumed by forming the protective film 5 using the sputtering method is calculated in advance on the core 3, and the strength or maximum reflectance FBG 7 in consideration of the loss amount is added. It is formed in the core 3 located in the sensor body 6.

  In consideration of suppressing the loss amount of the FBG 7 formed on the core 3 located in the sensor body 6, the film forming temperature by the sputtering method is preferably about 110 ° C. and is used as the protective film 3. When the grad 4 is made of a single mode quartz glass fiber and the outer diameter is 125 μm, the titanium layer 5a, the nickel layer 5b, and the gold layer 5c may be formed to have a thickness of about 300 nm, 400 nm, and 600 nm, respectively. desirable.

  In the present embodiment, a three-layer metal film composed of a titanium layer 5a, a nickel layer 5b, and a gold layer 5c is used as the protective film 5. However, the present invention is not necessarily limited to this and has high corrosion resistance and pitting corrosion resistance. A configuration in which a stainless alloy is coated, a configuration in which a nitride thin film is coated, and the like are also conceivable. The stainless steel alloy shown here is formed by artificially producing an oxide film having plasticity and structure that cannot be naturally formed on stainless steel by a sputtering method. On the other hand, a nitride thin film is formed by an RF sputtering device. In Al-N and Sn-N thin films in various states, a reactive sputtering method is used to deposit a nitride film by reacting a metal target in a nitrogen / argon mixed plasma at the same time. Is.

  The optical fiber sensor 1 having such a configuration uses an optical fiber sensor by using a metal film formed by a sputtering method for the protective film 5 as compared with a film made of a UV curable resin or the like generally used as the protective film 5 conventionally. 1 has high resistance in a high temperature and high humidity environment, and is resistant to distortion even when an external force is applied, and can maintain the physical detection performance of the sensor body 6.

  Moreover, when a metal coating is used for the protective coating 5, when fixing the optical fiber sensor 1 to the measurement site | part of the measuring object 9, the hard fixing members 8, such as a weld metal and solder, can be used. Thereby, since the fixing member 8 does not become a buffer material compared to the conventional case where a flexible member such as an optical adhesive is used for the fixing member 8, the amount of change in the measurement region is reduced in the sensor body 6. Since it is transmitted faithfully, it is possible to accurately measure the amount of change in the measurement site of the measurement object 9 with high accuracy.

  Here, although the hard fixing member 8 such as a weld metal or solder is known to have a sharp concavo-convex portion on the surface, the metal film constituting the protective film 5 is formed by a sputtering method. The phenomenon that the optical fiber sensor 1 is broken by this sharp uneven portion can be suppressed.

An optical fiber sensor module 10 configured to make it easier to handle the optical fiber sensor 1 using the protective coating 5 with a metal coating by sputtering is shown below.
As shown in FIG. 2, the optical fiber sensor module 10 includes support members 11a and 11b that make a pair with the optical fiber sensor 1 described above.
As shown in FIG. 3A, the paired support members 11a and 11b are formed of a metal material and are parallel with a separation distance longer than the member length of the sensor body 6 formed in the optical fiber sensor 1. Is arranged. The optical fiber sensor 1 is supported by a pair of support members 11a and 11b in the vicinity of both ends of the sensor body 6 so that the sensor body 6 is disposed between the pair of support members 11a and 11b. Is fixed via a fixing member 12.

Solder is used for the fixing member 12, and the supporting members 11 a and 11 b that extend in a strip shape in the length direction of the optical fiber sensor 1 and pair with the optical fiber sensor 1 are fixed on the surface. Yes. At this time, the fixing member 12 extending in a band shape in the length direction of the optical fiber sensor 1 is provided so that both end portions in the length direction are at the same position as both end portions of the pair of support members 11a and 11b. ing.
In the present embodiment, both are fixed to the fixing member 12 by soldering using solder. However, this is not necessarily limited to this, even if both are fixed to the fixing member 12 by welding using welding metal. good.

When the optical fiber sensor module 10 having such a configuration is installed at a measurement site of the measurement object 9, as shown in FIG. The supporting members 11a and 11b that make a pair so as not to act are arranged at the measurement site, and are fixed via fixing means such as welding or soldering.
Thus, the optical fiber sensor module 10 simplifies the attachment of the optical fiber sensor 1 to the measurement site and facilitates the handling thereof. Further, since the optical fiber sensor 1 can be installed at the measurement site of the measurement object 9 via the supporting members 11a and 11b that make a pair without directly touching the sensor main body 6 of the optical fiber sensor 1, the sensor main body 6 It does not cause a disturbance to the physical detection performance inherently provided.

  By the way, when the optical fiber sensor module 10 having the above-described configuration is subjected to a tension including a component perpendicular to the axial direction with respect to the optical fiber sensor 1, a fixed portion with each of the pair of support members 11a and 11b, specifically, In this case, deformation with a small radius of curvature occurs in the vicinity of both ends in the length direction of the fixing member 12 extending in a band shape in the length direction of the optical fiber sensor 1, and stress is concentrated and is easily broken.

  Therefore, in the present embodiment, as shown in FIG. 3A, the optical fiber sensor 1 is caused by the stress concentration generated in the vicinity of the fixing portion between the support members 11a and 11b that form a pair with the optical fiber sensor module 10. In order to suppress the phenomenon of breakage, the fixed end portion in the length direction of the support members 11a and 11b paired with the optical fiber sensor 1, that is, the fixed member 12 extending in a band shape in the length direction of the optical fiber sensor 1. The cushioning material 13 is provided at the end in the length direction. The buffer material 13 is made of a soft material such as an adhesive having elasticity in comparison with the fixing member 12 such as solder or weld metal. In this embodiment, the buffer material 13 is used for bonding high-precision parts such as an optical connector. A widely used epoxy adhesive is used.

The elastic modulus and the adhesive layer thickness of the buffer material 13 are assumed to have a component perpendicular to the axial direction that is expected to act on the optical fiber sensor 1 in advance, and the deformation amount of the optical fiber sensor 1 associated therewith is assumed. It calculates and adjusts so that this may not reach to a fixed part with each of the support members 11a and 11b which make a pair.
In addition, the fixing member 12 does not necessarily stick to an epoxy-based adhesive, and any material may be used as long as it has a higher viscoelasticity than the fixing member 12, but the viscosity before curing is high, It is even better if the adhesive layer thickness can be molded to 1 mm or more.

Furthermore, the configuration for suppressing the breakage of the optical fiber sensor 1 is not necessarily limited to the configuration described above.
For example, the fixing member 12 is extended in a band shape in the length direction of the optical fiber sensor 1 to the fixing portion of the supporting members 11a and 11b that make a pair with the optical fiber sensor 1, and the fixing strength thereof is the both ends in the length direction. The stress concentration tends to occur at the end of the fixing member 12 in the longitudinal direction when a tension including a component perpendicular to the axial direction is applied to the optical fiber sensor 1. May be dispersed and relaxed in a wide range toward the central portion of the fixing member 12 in the longitudinal direction.

  Specifically, as shown in FIG. 3 (b), the protective film 5 of the optical fiber sensor 1 positioned at the fixing portion with each of the supporting members 11a and 11b that make a pair is made wettable with the fixing member 12. Metallized with a metal material 14 made of a good material, and processed so that the apparent cross-sectional area of the optical fiber sensor 1 continuously decreases from the fixed end to the fixed center with each of the pair of support members 11a and 11b. To do. Thereby, since the fixing member 12 is continuously formed thicker from the end in the length direction of the optical fiber sensor 1 toward the center, the fixing strength also increases continuously.

  Alternatively, as shown in FIG. 4A, the outer peripheral surface of the protective film 5 is subjected to surface treatment to form a metallized film 15 having high wettability with respect to the fixing member 12, and then the optical fiber sensor 1 in the length direction. The application amount is adjusted so that the thickness of the fixing member 12 at the end is thin and the thickness at the center is large.

Furthermore, as shown in FIG. 4B, a configuration using a mold 16 made of a material such as a resin having high heat resistance may be used. The mold 16 is formed in a cylindrical shape, and the inner shape is cross-sectioned from the optical fiber sensor 1 so that the outer shape is fitted to a fixing surface of the supporting members 11a and 11b that make a pair with the optical fiber sensor 1. And is formed in a cavity having a tapered surface whose cross section expands from the end toward the inward center.
The fixing of the mold 16 filled with the fixing member 12 so as to embed the optical fiber sensor 1 through the cavity is fixed to the optical fiber sensor 1 of the pair of support members 11a and 11b. By fitting with the surface, the fixing member 12 is formed continuously thick from the end in the length direction toward the center, thereby increasing the fixing strength.

The application of the mold 16 formed of such a material as a resin is in addition to a configuration in which the fixing strength of the fixing member 12 extending in a band shape is continuously increased from both end portions in the length direction toward the central portion. Since the mold 16 serves as a buffer material, it is possible to more efficiently relieve stress concentration when a tension including a component perpendicular to the axial direction is applied to the optical fiber sensor 1.
The mold 16 may be any heat-resistant resin having a high elastic modulus such as polyimide.

  As described above, the fixing strength of the fixing member 12 extending in a band shape to the fixing portions of the supporting members 11a and 11b paired with the optical fiber sensor 1 is continuously increased from both end portions in the length direction toward the central portion. Even if a tension including a component perpendicular to the axial direction is applied to the optical fiber sensor 1, the deformation is applied not only to the longitudinal end portion of the fixing member 12 but also to the central portion. Since stress concentration can be alleviated by dispersing in a wide range, it is possible to suppress phenomena such as fracture.

  According to the above-described configuration, the optical fiber sensor 1 has a strength or maximum reflectance obtained by adding in advance a loss amount due to the film forming temperature when the clad 4 is coated with the protective film 5 on the core 3 positioned in the sensor body 6. Since the FBG 7 is formed, the physical quantity detection performance of the sensor body 6 may be lowered even if a metal film is applied to the protective film 5 and coated on the clad 4 using a sputtering method in which the film forming temperature is high. Therefore, it is possible to form the optical fiber sensor 1 having resistance to a high temperature / high humidity environment.

  Further, by using a metal film formed by sputtering for the protective film 5, even if an external force such as tension or bending acts on the optical fiber sensor 1 due to any factor, its shape is not easily distorted. It is possible to provide a physical quantity detection performance that is highly resistant to disturbance and has high accuracy and reliability.

Further, by using a metal film formed by sputtering for the protective film 5, a hard fixing member 12 such as solder or weld metal that may have sharp irregularities on the surface is applied to the measurement site of the optical fiber sensor 1. Even if it is used for fixing, it is possible to suppress the phenomenon that the optical fiber sensor 1 is broken.
As described above, since the hard fixing member 12 such as solder or weld metal can be used for fixing the optical fiber sensor 1 to the measurement site, the fixing member 12 functions as a buffer material like an optical adhesive. Therefore, it is possible to accurately measure the amount of change in the measurement site.

A pair of support members 11a and 11b made of a metal material is fixed to the optical fiber sensor 1 to form an optical fiber sensor module 10, thereby fixing the optical fiber sensor 1 to a measurement site via the support members 11a and 11b. Therefore, the configuration for attaching the optical fiber sensor 1 to the measurement site is simplified, and the optical fiber sensor 1 can be easily handled.
In addition, since the optical fiber sensor 1 is not directly touched when being attached to the measurement site, the external force accompanying the attaching operation is not applied to the optical fiber sensor 1, so that the sensor body 6 is protected and measured accurately. It becomes possible to arrange | position the optical fiber sensor 1 in a site | part.

  By adding a conversion mechanism to such an optical fiber sensor module 10, it is possible to use the optical fiber sensor 1, which mainly has distortion, temperature, etc., as a main measured quantity, for various measurements such as acceleration and displacement. In addition, measurement modules such as strain gauges, thermometers, accelerometers, and displacement meters can be formed.

  In configuring the optical fiber sensor module 10, since solder or weld metal is used for the fixing member 12 that fixes the optical fiber sensor 1 and the support members 11 a and 11 b, the optical fiber sensor module 10 is interposed between the measurement site and the sensor body 6. Since there is no flexible member that can serve as the buffer material 13 in any of the support members 11a and 11b and the fixing member 12, it is possible to accurately detect the amount of change in the measurement site.

  Further, since the buffer member 13 is provided at the end of the fixing member 12 in the longitudinal direction of the optical fiber sensor 1, even if a tension including a component perpendicular to the axial direction acts on the optical fiber sensor 1, Since deformation with a small curvature radius that tends to occur near the end of the fixing member 12 positioned in the longitudinal direction of the optical fiber sensor 1 can be prevented and stress concentration can be relaxed, phenomena such as fracture can be suppressed. Become.

  On the other hand, by continuously increasing the fixing strength of the fixing member 12 from the end in the longitudinal direction of the optical fiber sensor 1 toward the center, a component perpendicular to the axial direction with respect to the optical fiber sensor 1 can be obtained. Even if the tension is included, the deformation of the optical fiber sensor 1 can be dispersed over a wide range in the length direction of the fixing member 12 to relieve the stress concentration.

It is a figure which shows the detail of the optical fiber sensor which concerns on this invention. It is a figure which shows the outline of the optical fiber sensor module which concerns on this invention. It is a figure which shows the detail of the optical fiber sensor module which concerns on this invention. It is a figure which shows the other example of the optical fiber sensor module which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical fiber sensor 2 Optical fiber 3 Core 4 Clad 5 Protective film 5a Titanium layer 5b Nickel layer 5c Gold layer 6 Sensor main body 7 FBG (fiber Bragg grating)
8 Fixing member 9 Measurement object 10 Optical fiber sensor module 11a Support member 11b Support member 12 Fixing member 13 Buffer material 14 Metal member 15 Metallized film 16 Mold

Claims (4)

An optical fiber sensor in which a sensor body for detecting a physical quantity of an object to be measured is formed in at least a part of a length direction of an optical sensor comprising a core, a clad covering the core, and a protective film covering the clad,
The sensor body is configured in an FBG system in which a fiber Bragg grating (hereinafter referred to as FBG) is formed in the core,
The protective film is formed of a metal film formed by sputtering,
The optical fiber sensor, wherein the FBG is formed to have an intensity or maximum reflectance that takes into account a loss amount due to a film forming temperature when the clad is coated with the protective film. An optical fiber sensor module using the optical fiber sensor according to claim 1,
An optical fiber sensor comprising: a support member that is made of a metal material and arranged in pairs so as to sandwich a sensor body of the optical fiber sensor, and is fixed to the optical fiber sensor via a fixing member. module. The optical fiber sensor module according to claim 2,
While using a solder or weld metal for the fixing member that fixes the optical fiber sensor and the support member,
A buffer material is provided at an end portion of the fixing member positioned in the length direction of the optical fiber sensor. The optical fiber sensor module according to claim 2 or 3,
The fixing member extends in the length direction of the optical fiber sensor,
The optical fiber sensor module, wherein the fixing strength of the fixing member continuously increases from an end portion located in the length direction of the optical fiber sensor toward a central portion.

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