Patent Description:
Hitherto, there has been known a temperature measurement system including a temperature measurement object, an optical fiber, an accommodating tube in which the optical fiber is accommodated, and a conductive viscous material filled in the accommodating tube, in which the accommodating tube is fixed to the temperature measurement object.

The optical fiber is supported on the accommodating tube through intermediation of the conductive viscous material. With this, when distortion due to a change in temperature occurs in the temperature measurement object, the distortion that occurs in the temperature measurement object is prevented from being transmitted to the optical fiber (see, for example, Patent Literature <NUM>).

[PTL <NUM>] <CIT>. Other temperature sensing systems based on optical fibres are disclosed in <CIT> and <CIT>.

However, the optical fiber is supported on the accommodating tube through intermediation of the conductive viscous material. With this, the optical fiber is movable inside the accommodating tube in a direction in which a distance between the optical fiber and the temperature measurement object changes. Thus, for example, when the accommodating tube is fixed to a lower surface of the temperature measurement object, the optical fiber is significantly separated away from the temperature measurement object due to the gravity as compared to a case in which the accommodating tube is fixed to an upper surface of the temperature measurement object. In this case, there is a problem in that responsiveness of heat transfer from the temperature measurement object to the optical fiber is deteriorated.

This invention has been made to solve the problem as described above, and has an object to provide a temperature measurement system and a manufacturing method therefor, which are capable of preventing distortion that occurs in a temperature measurement object from being transmitted to an optical fiber, and improving responsiveness of heat transfer from the temperature measurement object to the optical fiber.

According to this invention, there is provided a temperature measurement system as defined in claim <NUM>.

According to this invention, there is provided a manufacturing method for a temperature measurement system as defined in claim <NUM>.

According to the temperature measurement system and the manufacturing method therefor of this invention, it is possible to prevent distortion that occurs in the temperature measurement object from being transmitted to the optical fiber, and to improve responsiveness of heat transfer from the temperature measurement object to the optical fiber.

First, an optical fiber being one of components of a temperature measurement system according to a first illustrative example is described. <FIG> is a configuration view for illustrating the optical fiber. Examples of an optical fiber <NUM> include a multipoint optical fiber <NUM> and a distributed optical fiber <NUM>. In the multipoint optical fiber <NUM>, temperature is measured at a plurality of set points in one optical fiber <NUM>. In the distributed optical fiber <NUM>, the temperature is continuously measured in one optical fiber <NUM>. Light of a broadband frequency or scattering light is used for measurement of the temperature using the optical fiber <NUM>. Examples of the scattering light include Rayleigh scattering light, Brillouin scattering light, and Raman scattering light.

In the first example, the optical fiber <NUM> in which a fiber Bragg grating (FBG) is used as a sensor unit is described.

The optical fiber <NUM> includes a core <NUM>, an FBG sensor unit <NUM> provided to the core <NUM>, a cladding <NUM> covering an outer periphery of the core <NUM>, and a covering portion <NUM> covering an outer periphery of the cladding <NUM>. The FBG sensor unit <NUM> is used for measuring the temperature using a relationship between a Bragg wavelength and the temperature. The FBG sensor unit <NUM> is arranged inside the core <NUM>. Examples of a material forming the covering portion <NUM> include an acrylate resin and a polyimide resin.

The covering portion <NUM> has a cover removed portion <NUM> in which the outer periphery of the cladding <NUM> is exposed. The cover removed portion <NUM> is formed in a region of the covering portion <NUM> which corresponds to the FBG sensor unit <NUM> in a radial direction of the optical fiber <NUM>. Thus, a portion of the optical fiber <NUM> in which the FBG sensor unit <NUM> is arranged has a radial dimension smaller than that of other portions of the optical fiber <NUM>.

A radial dimension of a portion of the optical fiber <NUM> in which the covering portion <NUM> is provided is <NUM>. A radial dimension of the cladding <NUM> is <NUM>. A radial dimension of the core <NUM> is <NUM>. The FBG sensor unit <NUM> is arranged in a range of about <NUM> in the core <NUM> in a longitudinal direction of the optical fiber <NUM>.

The FBG sensor unit <NUM> is obtained by forming a portion having a cyclically modulated refractive index in the core <NUM>. In the FBG sensor unit <NUM>, a steep reflection spectrum characteristic is obtained. <FIG> is a configuration view for illustrating the FBG sensor unit <NUM> of <FIG>. In the FBG sensor unit <NUM>, a refractive index of the core <NUM> changes at a cycle A.

<FIG> is a graph for showing characteristics of a reflection spectrum obtained in the FBG sensor unit <NUM> of <FIG>. In the FBG sensor unit <NUM>, a steep reflection spectrum is obtained. The light intensity is the largest at a center wavelength in the obtained reflection spectrum. The center wavelength of the reflection spectrum is a Bragg wavelength λb.

The relationship of the Bragg wavelength λb, the cycle Λ, and a refractive index "n" is represented by Expression (<NUM>) below.

The refractive index "n" changes depending on the temperature of the optical fiber <NUM>. The cycle A changes depending on the temperature of the optical fiber <NUM> and distortion transmitted from a temperature measurement object to the optical fiber <NUM>. Thus, when the distortion of the temperature measurement object is not transmitted to the optical fiber <NUM>, a relationship between the Bragg wavelength λb and temperature is measured in advance, and the temperature of the temperature measurement object is measured using the measured relationship and the Bragg wavelength λb.

Next, the temperature measurement system is described. <FIG> is a configuration diagram for illustrating the temperature measurement system including the optical fiber <NUM> of <FIG>. The temperature measurement system includes the optical fiber <NUM>, an optical circulator <NUM>, an amplified spontaneous emission (ASE) light source <NUM>, and a spectrum analyzer <NUM>.

The optical circulator <NUM> is connected to an end portion of the optical fiber <NUM> in the longitudinal direction. The optical circulator <NUM> converts an optical path passing through the optical circulator <NUM>.

The ASE light source <NUM> emits light of a relatively broadband frequency. The ASE light source <NUM> is connected to the optical circulator <NUM>. The light emitted from the ASE light source <NUM> is input to the optical circulator <NUM>.

The spectrum analyzer <NUM> is a wavelength measurement device. The spectrum analyzer <NUM> is connected to the optical circulator <NUM>. The light is input to the spectrum analyzer <NUM> via the optical circulator <NUM>.

In the temperature measurement system, the spectrum analyzer <NUM> measures the Bragg wavelength λb so that the temperature of the temperature measurement object is measured.

Next, problems in a related-art temperature measurement system are described. <FIG> is a perspective view for illustrating the related-art temperature measurement system. The related-art temperature measurement system includes a temperature measurement object <NUM>, the optical fiber <NUM>, a protective tube <NUM>, and a conductive viscous material <NUM>.

The optical fiber <NUM> is accommodated in the protective tube <NUM>. The protective tube <NUM> is filled with the conductive viscous material <NUM>. With this, the conductive viscous material <NUM> is arranged around the optical fiber <NUM>. The protective tube <NUM> is fixed to the temperature measurement object <NUM>.

<FIG> is an explanatory view for illustrating responsiveness of heat transfer in the temperature measurement system of <FIG>. In <FIG>, a case in which the protective tube <NUM> is fixed to an upper surface of the temperature measurement object <NUM> and a case in which the protective tube <NUM> is fixed to a lower surface of the temperature measurement object <NUM> are illustrated.

As compared to the case in which the protective tube <NUM> is fixed to the upper surface of the temperature measurement object <NUM>, in the case in which the protective tube <NUM> is fixed to the lower surface of the temperature measurement object <NUM>, the optical fiber <NUM> is significantly separated away from the temperature measurement object <NUM> due to the gravity acting on the optical fiber <NUM>.

As a result, as compared to the case in which the protective tube <NUM> is fixed to the upper surface of the temperature measurement object <NUM>, in the case in which the protective tube <NUM> is fixed to the lower surface of the temperature measurement object <NUM>, the responsiveness of the heat transfer from the temperature measurement object <NUM> to the optical fiber <NUM> is deteriorated. In other words, the responsiveness of the heat transfer in the temperature measurement system is deteriorated.

In order to suppress the deterioration of the responsiveness of the heat transfer in the temperature measurement system, it is conceivable that a radial dimension of the protective tube <NUM> is reduced to prevent movement of the optical fiber <NUM> in the radial direction with respect to the protective tube <NUM>. <FIG> is a view for illustrating the protective tube <NUM> and the optical fiber <NUM> when the radial dimension of the protective tube <NUM> of <FIG> is reduced so that the optical fiber <NUM> does not move in the radial direction with respect to the protective tube <NUM>.

When the optical fiber <NUM> does not move in the radial direction with respect to the protective tube <NUM>, the protective tube <NUM> is bent so that the optical fiber <NUM> is restrained at the bent portion of the protective tube <NUM>. With this, distortion is transmitted to the FBG sensor unit <NUM> from the temperature measurement object <NUM>. As a result, the temperature measurement accuracy of the temperature measurement system is deteriorated.

<FIG> is a perspective view for illustrating another related-art temperature measurement system. The another related-art temperature measurement system includes the temperature measurement object <NUM>, the optical fiber <NUM>, a casing <NUM>, and the conductive viscous material.

The optical fiber <NUM> is accommodated in the casing <NUM>. The casing <NUM> is filled with the conductive viscous material. With this, the conductive viscous material is arranged around the optical fiber <NUM>. The casing <NUM> is fixed to the temperature measurement object <NUM>.

The optical fiber <NUM> is arranged to be bent into an S2 shape inside the casing <NUM>. The casing <NUM> has an inlet portion <NUM> and an outlet portion <NUM> through which the optical fiber <NUM> is inserted.

In the inlet portion <NUM> and the outlet portion <NUM>, the optical fiber <NUM> is fixed to the casing <NUM>. Inside the casing <NUM>, the optical fiber <NUM> is not fixed to the casing <NUM>. Thus, distortion from the temperature measurement object <NUM> is not transmitted to the optical fiber <NUM>.

However, the optical fiber <NUM> is bent into the S2 shape, and hence a portion of the temperature measurement object <NUM> which is measured in temperature is limited. In other words, a space in the temperature measurement object <NUM> in which the optical fiber <NUM> is not arranged becomes larger. As a result, the density of the portion which is measured in temperature by the temperature measurement system is reduced.

In the related-art temperature measurement system, a relationship between Brillouin scattering light and temperature is measured in advance, and the temperature of the temperature measurement object <NUM> is measured from new Brillouin scattering light using the measured relationship.

In view of the above discussion, the inventors of the present invention have focused on a problem in that, in the related-art temperature measurement system, the temperature cannot be measured with high accuracy and high density without deteriorating the responsiveness of the heat transfer.

In order to solve the problem newly focused as described above, the first illustrative example provides a temperature measurement system and a manufacturing method therefor in which the optical fiber <NUM> can be freely wired without deteriorating the responsiveness of the heat transfer, and the temperature can be measured with high accuracy and high density.

Next, the temperature measurement system according to the first illustrative example is described. <FIG> is a perspective view for illustrating the temperature measurement system according to the first illustrative example of this invention. In <FIG>, a temperature measurement system in a case in which the optical fiber <NUM> is arranged on a straight line is illustrated. The temperature measurement system includes the optical fiber <NUM>, the temperature measurement object <NUM>, an intermediate material <NUM>, and a pressing jig <NUM>.

The optical fiber <NUM> is provided on the temperature measurement object <NUM>. In <FIG>, the optical fiber <NUM> is provided on the upper surface of the temperature measurement object <NUM>, but may be provided on the lower surface of the temperature measurement object <NUM>. The optical fiber <NUM> has sensitivity to both the temperature and the distortion.

The intermediate material <NUM> is provided on the temperature measurement object <NUM>. The intermediate material <NUM> is in contact with the optical fiber <NUM>. The intermediate material <NUM> restricts movement of the optical fiber <NUM> in a direction in which the optical fiber <NUM> is separated away from the temperature measurement object <NUM>.

The pressing jig <NUM> is provided on the temperature measurement object <NUM>. The pressing jig <NUM> is fixed to the temperature measurement object <NUM>. The pressing jig <NUM> holds the optical fiber <NUM> through intermediation of the intermediate material <NUM>. In other words, the pressing jig <NUM> holds the optical fiber <NUM> and the intermediate material <NUM> such that the optical fiber <NUM> and the intermediate material <NUM> are not separated away from the temperature measurement object <NUM>. Further, the pressing jig <NUM> presses the optical fiber <NUM> against the temperature measurement object <NUM> through intermediation of the intermediate material <NUM>. Thus, the optical fiber <NUM> is pressed toward the temperature measurement object <NUM>.

The pressing jig <NUM> is required to be firmly fixed to the temperature measurement object <NUM>. Examples of a method of fixing the pressing jig <NUM> to the temperature measurement object <NUM> include a method of using a pressure-sensitive adhesive, an adhesive, a screw, or a bolt.

The intermediate material <NUM> is in contact with the optical fiber <NUM> such that the optical fiber <NUM> can freely expand and contract with respect to the temperature measurement object <NUM> and the intermediate material <NUM> in the longitudinal direction of the optical fiber <NUM>. In other words, the optical fiber <NUM> can expand and contract in the longitudinal direction of the optical fiber <NUM> due to a change in the temperature of the optical fiber <NUM> with respect to the temperature measurement object <NUM> and the intermediate material <NUM>.

The intermediate material <NUM> is formed of a material softer than the pressing jig <NUM>. Thus, distortion that occurs in the temperature measurement object <NUM> is prevented from being transmitted to the optical fiber <NUM>. Examples of the material forming the intermediate material <NUM> include a sponge, a foam material, a buffer material, and a fibrous material. Examples of the fibrous material include cotton.

<FIG> is a perspective view for illustrating a modification example of the temperature measurement system of <FIG> is an illustration of a temperature measurement system in a case in which the optical fiber <NUM> is bent. Further, in <FIG>, the temperature measurement object <NUM> is a honeycomb sandwich structure. Also in the temperature measurement system illustrated in <FIG>, the roles of the intermediate material <NUM> and the pressing jig <NUM> are the same as the roles of the intermediate material <NUM> and the pressing jig <NUM> in the temperature measurement system illustrated in <FIG>.

In the temperature measurement system illustrated in each of <FIG>, the optical fiber <NUM> is not fixed to the temperature measurement object <NUM>. Thus, even when the temperature of the temperature measurement object <NUM> is changed, and the temperature measurement object <NUM> expands and contracts, distortion caused by heat generated in the temperature measurement object <NUM> is not transmitted to the optical fiber <NUM>.

Further, the optical fiber <NUM> is pressed against the temperature measurement object <NUM>. Thus, even when the optical fiber <NUM> is arranged on any of the upper surface and the lower surface of the temperature measurement object <NUM>, the sensitivity of the temperature measurement by the temperature measurement system is not deteriorated.

Next, the merit of the temperature measurement system in the case in which the temperature measurement object <NUM> is a honeycomb sandwich structure is described. The honeycomb sandwich structure generally includes skin materials formed of fiber-reinforced plastic and a honeycomb core.

With this, the honeycomb sandwich structure has a lightweight and highly rigid structure. Thermal deformation occurs in the honeycomb sandwich structure due to heat input by sunlight, heat generation from a mounted device, or the like. Thus, an earth-directed axis angle in mission instruments such as a camera and an antenna mounted on an artificial satellite is changed. In a geostationary satellite arranged apart from the earth by about <NUM><NUM>, when the earth-directed axis angle is slightly changed, accuracy of Earth observation and accuracy of positioning are significantly reduced.

Accordingly, it is important to maintain the temperature of the honeycomb sandwich structure as uniform as possible by thermal control using a heater or the like to prevent thermal deformation of the honeycomb sandwich structure.

As illustrated in <FIG>, the optical fibers <NUM> are wired to both the pair of skin materials in the honeycomb sandwich structure being the temperature measurement object <NUM>, thereby being capable of measuring the temperature of the honeycomb sandwich structure with high density and high accuracy. As a result, thermal deformation that occurs in the honeycomb sandwich structure can be prevented by precise thermal control.

Next, the manufacturing method for the temperature measurement system is described. In this case, the manufacturing method for the temperature measurement system in the case in which the temperature measurement object <NUM> is a honeycomb sandwich structure is described. <FIG> is a flowchart for illustrating the manufacturing method for the temperature measurement system according to the first illustrative example of this invention.

First, in Step S101, a temporary fixing step is performed. <FIG> is an explanatory view for illustrating the temporary fixing step of <FIG>. In the temporary fixing step, the optical fiber <NUM> is wired to the skin material of the honeycomb sandwich structure being the temperature measurement object <NUM>, and the optical fiber <NUM> is temporarily fixed to the honeycomb sandwich structure using tapes <NUM> being temporary fixing members. Further, in the temporary fixing step, the optical fiber <NUM> is bent, and the bent portions in the optical fiber <NUM> are temporarily fixed to the honeycomb sandwich structure using the tapes <NUM>.

After that, as illustrated in <FIG>, in Step S102, a holding step is performed. <FIG> is an explanatory view for illustrating the holding step of <FIG>. In the holding step, the pressing jig <NUM> holds the optical fiber <NUM> through intermediation of the intermediate material <NUM>, and the pressing jig <NUM> is mounted to the temperature measurement object <NUM> such that the pressing jig <NUM> presses the optical fiber <NUM> against the temperature measurement object <NUM> through intermediation of the intermediate material <NUM>.

In the holding step, the optical fiber <NUM> can expand and contract in the longitudinal direction of the optical fiber <NUM> due to the change in the temperature of the optical fiber <NUM> with respect to the temperature measurement object <NUM> and the intermediate material <NUM>.

After that, as illustrated in <FIG>, in Step S103, a temporary-fixing releasing step is performed. In the temporary-fixing releasing step, as illustrated in <FIG>, the tapes <NUM> are removed from the optical fiber <NUM> and the temperature measurement object <NUM>. With this, the temporary fixing of the optical fiber <NUM> to the temperature measurement object <NUM> with the tapes <NUM> is released. In this manner, the manufacture of the temperature measurement system is completed.

As described above, the temperature measurement system according to the first embodiment of this illustrative example includes the temperature measurement object <NUM> and the optical fiber <NUM> being provided on the temperature measurement object <NUM> and having sensitivity to both the temperature and the distortion.

Further, the temperature measurement system includes the intermediate material <NUM> in contact with the optical fiber <NUM>, and the pressing jig <NUM> that holds the optical fiber <NUM> through intermediation of the intermediate material <NUM> and presses the optical fiber <NUM> against the temperature measurement object <NUM> through intermediation of the intermediate material <NUM>. The optical fiber <NUM> can expand and contract in the longitudinal direction of the optical fiber <NUM> due to the change in the temperature of the optical fiber <NUM> with respect to the temperature measurement object <NUM> and the intermediate material <NUM>.

With this, the optical fiber <NUM> can be freely wired without deteriorating the sensitivity of the temperature measurement, and the temperature of the temperature measurement object <NUM> can be measured with high accuracy and high density. In other words, distortion that occurs in the temperature measurement object <NUM> can be prevented from being transmitted to the optical fiber <NUM>, and the responsiveness of the heat transfer from the temperature measurement object <NUM> to the optical fiber <NUM> can be improved.

In the first illustrative example, the configuration of the optical fiber <NUM> including the FBG sensor unit <NUM> is described. However, the present invention is not limited thereto, and other multipoint optical fibers <NUM> and distributed optical fibers <NUM> may be employed.

Further, in the modification example of the first illustrative example, the honeycomb sandwich structure is described as an example of the temperature measurement object <NUM>. However, the present invention is not limited thereto, and the temperature measurement object <NUM> can be applied to other satellite-mounted devices.

Second illustrative example not forming part of the present invention <FIG> is a perspective view for illustrating a temperature measurement system according to a second illustrative example of this invention. In the first illustrative example, the configuration in which the FBG sensor unit <NUM> is covered with the pressing jig <NUM> is described. In contrast, in the second illustrative example, the optical fiber <NUM> is held by a pair of short pressing jigs <NUM>. The FBG sensor unit <NUM> is not covered with the pressing jig <NUM>. With this, the configuration of the temperature measurement system is simplified.

<FIG> is a perspective view for illustrating a modification example of the temperature measurement system of <FIG> is an illustration of a temperature measurement system in a case in which the optical fiber <NUM> is bent. Further, in <FIG>, the temperature measurement object <NUM> is a honeycomb sandwich structure.

In the temperature measurement system according to the first illustrative example, the entire FBG sensor unit <NUM> of the optical fiber <NUM> is covered with the pressing jig <NUM>. In contrast, in the temperature measurement system illustrated in each of <FIG>, the optical fiber <NUM> is held by the pair of pressing jigs <NUM> such that the optical fiber <NUM> is not separated away from the temperature measurement object <NUM>. In the temperature measurement system according to the second illustrative example, the volume of the intermediate material <NUM> and the pressing jig <NUM> is smaller than that of the temperature measurement system according to the first illustrative example. Other configurations are the same as those of the first illustrative example.

As described above, with the temperature measurement system according to the second illustrative example of this invention, each of the pair of pressing jigs <NUM> holds the optical fiber <NUM> through intermediation of the intermediate material <NUM>. With this, the same effects as those of the first illustrative example can be obtained, and as compared to the first illustrative example the configuration of the temperature measurement system can be simplified.

Third illustrative example not forming part of the present invention <FIG> is a perspective view for illustrating a temperature measurement system according to a third illustrative example of this invention. In the first illustrative example, the configuration in which the optical fiber <NUM> is arranged between the temperature measurement object <NUM> and the intermediate material <NUM> is described. In contrast, in the third illustrative example, a paste-like substance <NUM> is provided around the optical fiber <NUM>.

Thus, the paste-like substance <NUM> is provided in a gap between the optical fiber <NUM> and the intermediate material <NUM> and a gap between the temperature measurement object <NUM> and the intermediate material <NUM>. The paste-like substance <NUM> adheres to the temperature measurement object <NUM>, the optical fiber <NUM>, and the intermediate material <NUM>.

As the paste-like substance <NUM>, one having an NLGI consistency number of <NUM> or more and <NUM> or less is used. An adhesion step of allowing the paste-like substance <NUM> to adhere to the temperature measurement object <NUM> and the optical fiber <NUM> is performed after the temporary fixing step and before the holding step. With the holding step, the paste-like substance <NUM> adheres to the intermediate material <NUM>.

<FIG> is a perspective view for illustrating a modification example of the temperature measurement system of <FIG>. In <FIG>, a temperature measurement system in a case in which the optical fiber <NUM> is bent is illustrated. Further, in <FIG>, the temperature measurement object <NUM> is a honeycomb sandwich structure.

In the temperature measurement system according to the first illustrative example, the optical fiber <NUM> is arranged between the temperature measurement object <NUM> and the intermediate material <NUM>. Thus, in the temperature measurement system according to the first illustrative example, a gap may be formed by the temperature measurement object <NUM>, the optical fiber <NUM>, and the intermediate material <NUM>. In contrast, in the temperature measurement system illustrated in each of <FIG>, the paste-like substance <NUM> is provided around the optical fiber <NUM>.

The paste-like substance <NUM> adheres to the temperature measurement object <NUM>, the optical fiber <NUM>, and the intermediate material <NUM>. With this, the optical fiber <NUM> is firmly held on the temperature measurement object <NUM>, and heat is easily transferred from the temperature measurement object <NUM> to the optical fiber <NUM>. Other configurations are the same as those of the first illustrative example. The other configurations may be the same as those of the second illustrative example.

As described above, the temperature measurement system according to the third illustrative example of this invention includes the paste-like substance <NUM> which adheres to the temperature measurement object <NUM> and the optical fiber <NUM>. With this, the optical fiber <NUM> is firmly held on the temperature measurement object <NUM>, and heat is easily transferred from the temperature measurement object <NUM> to the optical fiber <NUM>.

<FIG> is a perspective view for illustrating a temperature measurement system according to this invention. In the third illustrative example, the configuration in which, after the paste-like substance <NUM> adheres around the optical fiber <NUM>, the intermediate material <NUM> is provided on the optical fiber <NUM> is described. In contrast, according to the present invention, a paste-like substance is infiltrated into the intermediate material <NUM>. The paste-like substance in the fourth embodiment is the same as the paste-like substance in the third embodiment.

<FIG> is a perspective view for illustrating a modification example of the temperature measurement system of <FIG>. In <FIG>, a temperature measurement system in the case in which the optical fiber <NUM> is bent is illustrated. Further, in <FIG>, the temperature measurement object <NUM> is a honeycomb sandwich structure.

In the temperature measurement system according to the third illustrative example, the paste-like substance <NUM> adheres to the temperature measurement object <NUM> and the optical fiber <NUM> so that the optical fiber <NUM> is held on the pressing jig <NUM> through intermediation of the intermediate material <NUM>. In contrast, in the temperature measurement system illustrated in each of <FIG>, the intermediate material <NUM> containing the paste-like substance infiltrated therein covers the periphery of the optical fiber <NUM>.

With the intermediate material <NUM> containing the paste-like substance infiltrated therein, the optical fiber <NUM> is firmly held on the temperature measurement object <NUM>, and heat is easily transferred from the temperature measurement object <NUM> to the optical fiber <NUM>. Other configurations are the same as those of the third embodiment.

Claim 1:
A temperature measurement system, comprising:
- a temperature measurement object (<NUM>);
- an optical fiber (<NUM>) provided on the temperature measurement object (<NUM>);
- an intermediate material (<NUM>) which is provided on the optical fiber (<NUM>) and
- a pressing jig (<NUM>) which is provided on the temperature measurement object (<NUM>), and is configured to press the optical fiber (<NUM>) against the temperature measurement object (<NUM>) through intermediation of the intermediate material (<NUM>),
- wherein the optical fiber (<NUM>) is expandable and contractible in a longitudinal direction of the optical fiber (<NUM>) due to a change in a temperature of the optical fiber (<NUM>) with respect to the temperature measurement object (<NUM>) and the intermediate material (<NUM>),
characterized in that the intermediate material (<NUM>) contains a paste-like substance infiltrated therein,
wherein the paste-like substance has an NLGI consistency number of <NUM> or more and <NUM> or less.