Patent Publication Number: US-11041741-B2

Title: Optical fiber sensor device and optical fiber sensor system

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2018-181904 filed on Sep. 27, 2018 the disclosure of which is incorporated by reference herein. 
     TECHNICAL FIELD 
     The present disclosure relates to an optical fiber sensor device and an optical fiber sensor system. 
     RELATED ART 
     Recent years have seen the development of technology in which optical fibers are employed in sensing. Optical fiber sensors employed in such sensing differ from traditional electrical sensors in that the sensor section thereof does not require a power source. Such optical fiber sensors are thus well-suited to deployment in locations where power supply would be difficult, such as within sealed devices. 
     Distributed optical fiber sensing is a type of optical fiber sensing in which an optical fiber can perform measurements along its length direction, and in which the optical fiber itself also serves as a sensor medium. For example, K. Koizumi, et al, “High-Speed Distributed Strain Measurement using Brillouin Optical Time-Domain Reflectometry Based-On Self-Delayed Heterodyne Detection”, ECOC2015, P.1.07, September 2015 (Non-Patent Document 1), discloses technology relating to distributed optical fiber sensing. 
     In distributed optical fiber sensing, when there is an arrangement of plural measurement locations, the distance from a light source differs at each of the measurement locations, and therefore the light transmission loss also differs with each distance. The difference in transmission loss to the measurement locations causes differences to appear in the intensity of scattered light received by an optical fiber sensor device. Reception sensitivities at the plural measurement locations do not accordingly match each other, with difficulties anticipated when comparing the measurement results from the plural measurement locations. 
     In order to perform comparison of the measurement results from plural measurement locations, there is accordingly a desire to make the reception sensitivities at the plural measurement locations substantially the same as each other. 
     SUMMARY 
     In consideration of the above circumstances, an object of the present disclosure is to provide a novel and improved optical fiber sensor device and optical fiber sensor system that are capable of making reception sensitivities at plural measurement locations substantially the same as each other, thereby facilitating comparison of measurement results at the plural measurement locations. 
     In order to solve the above issues, an aspect of the present disclosure provides an optical fiber sensor device including a control section configured to compute a physical quantity in an optical fiber installed at plural measurement locations based on intensity of scattered light received, and to compute an average of the computed physical quantity for the optical fiber. The control section is configured to compute the average of the physical quantity based on the computed physical quantity and on a length of the optical fiber. A length of the optical fiber installed at the respective measurement location is increased as a distance between a light source and the respective measurement location increases. 
     The control section may also be configured to compensate for a difference in length of the optical fiber installed at the respective measurement location and to compute the average of the physical quantity at the compensated length. 
     The control section may also be configured to compute the physical quantity in the optical fiber installed at the plural measurement locations as the physical quantity for substantially the same length. 
     The optical fiber may be installed so as to link the plural measurement locations together in a row. The control section may be configured to compute the physical quantity in the optical fiber installed as the row link, and to compute an average of the computed physical quantity of the optical fiber installed as the row link. 
     The control section may employ Brillouin optical time domain reflectometry (BOTDR) to compute the physical quantity in the optical fiber and to compute the average of the physical quantity. 
     In order to solve the above issues, another aspect of the present disclosure provides an optical fiber sensor system including a light source section, an optical fiber, a light reception section, and a control section. The light source section employs a light source to generate input light. The optical fiber is installed at plural measurement locations and is configured to scatter the input light to generate scattered light. The light reception section is configured to receive the scattered light generated inside the optical fiber. The control section is configured to compute a physical quantity in the optical fiber based on intensity of the scattered light received, and to compute an average of the computed physical quantity for the optical fiber. The control section is also configured to compute the average of the physical quantity based on the computed physical quantity and on a length of the optical fiber. The length of the optical fiber installed at the respective measurement location is increased as a distance between the light source and the respective measurement location increases. 
     As described above, the present disclosure provides a novel and improved optical fiber sensor device and optical fiber sensor system that are capable of making the reception sensitivities at plural measurement locations substantially the same as each other, thereby facilitating comparison of measurement results at the plural measurement locations. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram illustrating an example of configuration of an optical fiber sensor system according to an exemplary embodiment of the present disclosure. 
         FIG. 2  is a diagram to explain intensity of scattered light received from an optical fiber  210 . 
         FIG. 3  is a diagram to explain processing to compute a physical quantity from the intensity of scattered light received according to the same exemplary embodiment. 
         FIG. 4  is a diagram to explain an example of a flow of operation to compute an average of a physical quantity using an optical fiber sensor system according to the same exemplary embodiment. 
         FIG. 5  is a diagram to explain an example of a measurement location  220  according to a second exemplary embodiment. 
         FIG. 6  is a diagram to explain an example of a method to compute a compensated amount for a moisture-sensitive material H according to the same exemplary embodiment. 
         FIG. 7  is a block diagram illustrating an example of a hardware configuration for configuration according to an exemplary embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Detailed explanation follows regarding preferable exemplary embodiments of the present disclosure, with reference to the appended drawings. In the present specification and in the drawings, configuration elements having effectively the same functional configuration as each other are allocated the same reference numerals and duplicate explanation is accordingly omitted. 
     1. FIRST EXEMPLARY EMBODIMENT 
     1-1 Overview 
     First, explanation will be given regarding an overview of the present disclosure. 
     Recent years have seen the development of technology relating to optical fiber sensors that perform sensing using an optical fiber as a sensor medium. Advantages of optical fiber sensors over battery-operated sensors include not requiring a power supply and having a smaller diameter and lighter weight etc. Employing optical fiber sensors also enables a sensor section installed to an object to be measured to be spaced apart from parts of the configuration where the light source and light receiver are provided. Sensing with an optical fiber sensor is thus expected to be applicable to monitoring infrastructure such as buildings. 
     Types of optical fiber sensors include distributed optical fiber sensors in which an optical fiber is itself employed as a sensing medium in the sensor section. Employing distributed optical fiber sensors enables measurement of the distribution of a physical quantity along the length direction of the optical fiber. Examples of such a physical quantity include temperature and strain. 
     For example, distributed optical fiber sensors employ optical time domain reflectometry (OTDR). In OTDR, the optical fiber sensor device emits pulses of light into the optical fiber, and receives backscattered light generated inside the optical fiber. The location in the optical fiber where scattering occurred is determined by measuring the time taken from when the optical fiber sensor device emitted the pulse of light, to when the backscattered light is received by the optical fiber sensor device. Namely, when employing OTDR, it is possible to measure the distribution of a physical quantity along the length direction of the optical fiber. Temperature, amount of strain etc. can be computed based on the amount of change in intensity and the amount of change in the frequency of the backscattered light received. 
     A connection is made between two measurement locations using an optical fiber. The greater the distance between the optical fiber sensor device and the measurement location, the more transmission loss occurs in the intensity of the scattered light. Namely, differences in reception sensitivity arise between the sensor sections at the respective measurement locations. Such differences are anticipated to cause difficulties when comparing measurement results from plural measurement locations. 
     The technical concept of an exemplary embodiment of the present disclosure was arrived at in consideration of the point described above, and has the following features. A control section is provided configured to compute a physical quantity in an optical fiber installed at plural measurement locations based on intensity of scattered light received, and to compute an average of the computed physical quantity for the optical fiber. The control section is configured to compute the average of the physical quantity based on the computed physical quantity and on a length of the optical fiber. A length of the optical fiber installed at the respective measurement location is increased as a distance between a light source and the respective measurement location increases. 
     These features make reception sensitivity substantially the same between plural measurement locations, thereby enabling easy comparison of measurement results from these plural measurement locations. 
     Explanation follows regarding an example of distributed optical fiber sensing. 
     1-2. Example Configuration 
     First, explanation follows regarding an example of a configuration of an optical fiber sensor system according to an exemplary embodiment of the present disclosure.  FIG. 1  is a block diagram illustrating an example of a configuration of an optical fiber sensor system according to an exemplary embodiment of the present disclosure. This optical fiber sensor system includes an optical fiber sensor device  10 , an optical fiber  210 , and measurement locations  220 . Note that measurement locations  220   a ,  220   b , and  220   c  are disposed so as to be arranged along the optical fiber  210 . 
     Optical Fiber Sensor Device  10   
     The optical fiber sensor device  10  according to the present exemplary embodiment is a measurement device capable of measuring a physical quantity at the measurement locations  220  using the optical fiber  210 . Examples of the physical quantity include the temperature and strain etc. at the measurement locations  220 . 
     The optical fiber sensor device  10  includes a control section  110 , a light source section  120 , a circulator  130 , and a light reception section  140 . 
     Control Section  110   
     The control section  110  according to the present exemplary embodiment has a function of performing calculations regarding the physical quantity at the measurement locations  220   a  to  220   c  based on the intensity of scattered light waves received by the light reception section  140 . Specifically, the control section  110  measures the physical quantity along the length direction of the optical fiber  210  based on the scattered light received, and computes an average of the physical quantity in the optical fiber  210  installed at the plural measurement locations  220   a  to  220   c . The control section  110  also has a function of controlling the light source section  120  and the light reception section  140 . The control section  110  may be configured as a CPU, a general purpose or a special purpose processor or other types of processing circuitry. 
     Light Source Section  120   
     The light source section  120  according to the present exemplary embodiment has a function of generating input light to be introduced into the optical fiber  210 . Note that the light source section  120  introduces the input light into the optical fiber  210  through the circulator  130 , described later. The input light may, for example, be configured by pulses of light. Pulses of light can be particularly effective as the input light when making time-resolved measurements of the physical quantity. The light source section  120  may include an optical divider, with the optical divider being employed to generate reference light when the input light is being generated. 
     The light source section  120  includes, for example, a semiconductor laser (laser diode) and an electro-optic modulator. 
     Circulator  130   
     The circulator  130  according to the present exemplary embodiment is an optical divider that takes the input light input from the light source section  120  and emits this light toward the optical fiber  210 , and takes scattered light input from the optical fiber  210  and emits this light toward the light reception section  140 . 
     Light Reception Section  140   
     The light reception section  140  according to the present exemplary embodiment has a function of receiving scattered light generated inside the optical fiber  210 . The light reception section  140  receives the scattered light via the circulator  130 . 
     The light reception section  140  includes, for example, a balanced detector (balanced photodiode), and an electrical spectrum analyzer, or other type of circuitry or device configured to receive light and measure intensity of the received light. 
     Optical Fiber  210   
     The optical fiber  210  according to the present exemplary embodiment is employed when the optical fiber sensor device  10  measures the physical quantity at the respective measurement locations  220   a  to  220   c . The optical fiber  210  may be installed so as to connect the optical fiber sensor device  10  and the respective measurement locations  220   a  to  220   c  together in a row. The scattered light generated at segments of the optical fiber installed at the respective measurement locations  220   a  to  220   c  changes according to the physical quantity at the respective measurement locations  220   a  to  220   c.    
     Installation may be performed such that a length of the optical fiber installed at each of the respective measurement locations  220   a  to  220   c  is increased as the distance between the optical fiber sensor device  10  and the respective measurement locations  220   a  to  220   c  increases. 
     Measurement Locations  220   
     The measurement locations  220   a  to  220   c  according to the present exemplary embodiment are locations where the physical quantity is measured. The measurement locations  220   a  to  220   c  are each installed with a segment of the optical fiber  210 . The measurement locations  220   a  to  220   c  may be specific devices or may be spaces. For example, in cases in which the measurement locations  220  are specific devices, the optical fiber  210  may be wound around the measurement locations  220 . The manner in which the segments of the optical fiber  210  are installed at the measurement locations  220  is not limited to the above example. 
     Explanation has been given regarding an example of a configuration of the optical fiber sensor system according to the present exemplary embodiment. Note that the configuration described with reference to  FIG. 1  is merely an example, and the functional configuration of the optical fiber sensor system according to the present exemplary embodiment is not limited to this example. The functional configuration of the optical fiber sensor system according to the present exemplary embodiment may be freely modified according to specification and application. For example, configuration other than the control section  110  may be provided independently so as to reside in a separate device from the optical fiber sensor device  10 , such as in a configuration in which, for example, the control section  110  controls other configuration over a network. 
     1-2. Example of Operation 
     Explanation follows regarding an example of processing in the optical fiber sensor system according to the present exemplary embodiment. Note that as an example, in the following explanation the optical fiber sensor performs distributed measurement capable of continuous measurements along the optical fiber. 
     First, explanation follows regarding the intensity of the scattered light received from the optical fiber  210 .  FIG. 2  is a diagram to explain the intensity of the scattered light received from the optical fiber  210 . The optical fiber sensor device  10 , the optical fiber  210 , and the measurement locations  220   a  to  220   c  are illustrated at the top of  FIG. 2 . As illustrated at the top of  FIG. 2 , there is surplus length for the optical fiber  210  installed at the measurement locations  220   a  to  220   c.    
     The intensity of the scattered light from the optical fiber  210  is illustrated against distance from the optical fiber sensor device  10  at the bottom of  FIG. 2 . Note that A1 represents the total length of the optical fiber  210 , the measurement length Da represents the length of the surplus length of optical fiber installed at the measurement location  220   a , the measurement length Db represents the length of the surplus length of optical fiber installed at the measurement location  220   b , and the measurement length Dc represents the length of the surplus length of optical fiber installed at the measurement location  220   c.    
     The greater the distance from the optical fiber sensor device  10 , the greater the transmission distance of the input light and the scattered light through the optical fiber  210 . This results in a decrease in the intensity of the scattered light from the optical fiber  210  received by the light reception section  140 . As illustrated at the bottom of  FIG. 2 , the distance of the measurement length D is increased as the distance from the optical fiber sensor device  10  increases. In the example of  FIG. 2 , since the distance from the optical fiber sensor device  10  increases in sequence through the measurement locations  220   a ,  220   b ,  220   c , the measurement lengths D are also increased in the sequence of the measurement lengths Da, Db, Dc. 
     The light reception section  140  then computes the physical quantity from the intensity of the scattered light received. The method for computing the physical quantity depends on the type of physical quantity and conditions at the measurement locations  220 .  FIG. 3  is a diagram to explain processing to compute the physical quantity from the intensity of the scattered light received in the first exemplary embodiment. The intensity of the scattered light from the optical fiber  210  against distance from the optical fiber sensor device  10  is illustrated at the top of  FIG. 3 . The computed physical quantity against the distance from the optical fiber sensor device  10  is illustrated at the bottom of  FIG. 3 . 
     The control section  110  computes a specific type of physical quantity from the intensity of the scattered light. The control section  110  computes from the computed physical quantity an average of the physical quantity at each of the optical fiber measurement lengths Da to Dc installed at the respective measurement locations  220   a  to  220   c . When computing these averages, a unit distance is made to be the same between the respective measurement locations  220   a  to  220   c . The control section  110  computes the physical quantity against distance from the optical fiber sensor device  10  as the physical quantity for the same length at each of the measurement lengths Da to Dc. 
     In the case of the example illustrated at the bottom of  FIG. 3 , the control section  110  computes the physical quantity at the measurement lengths Da to Dc by computing as the physical quantity at measurement points Pa to Pc. As illustrated at the bottom of  FIG. 3 , the control section  110  computes an average of the physical quantity for each of the measurement lengths Da to Dc as the physical quantity for the measurement points Pa to Pc. As illustrated at the bottom of  FIG. 3 , the measurement points Pa to Pc are each treated as a single point. The control section  110  thereby computes the average of the physical quantity so as to compensate for the differences between the lengths of the respective measurement lengths Da to Dc. Note that a length A2 is a length obtained by subtracting the lengths of segments of the optical fiber  210  at the measurement locations  220   a  to  220   c  from the total length A1 of the optical fiber  210 . In the example at the bottom of  FIG. 3 , the measurement points Pa to Pc are each illustrated as a single point. However, the physical quantity does not necessarily have to be computed for a single point at the measurement lengths Da to Dc using compensation by the control section  110 . The control section  110  may compensate the measurement lengths Da to Dc to substantially the same length as each other. The control section  110  achieves compensation so as to enable the measurement results from the measurement locations  220   a  to  220   c  to be compared with each other. 
     As described above, installation is performed so as to increase the length of the optical fiber installed at each of the measurement locations  220   a  to  220   c  as the distance between the optical fiber sensor device  10  and the respective measurement location  220   a  to  220   c  increases. Namely, the length of the measurement length D is made longer as the distance from the optical fiber sensor device  10  increases. Accordingly, by the control section  110  computing an average as the physical quantity for the measurement points Pa to Pc, the total intensity of the scattered light is substantially the same at the measurement locations  220   a  to  220   c , i.e. the reception sensitivities are substantially the same as each other at the measurement locations  220   a  to  220   c.    
     This functionality enables the reception sensitivities to be made substantially the same at the plural measurement locations. 
     Note that the graphs illustrated in  FIG. 2  and  FIG. 3  are merely examples, and there is no limitation to these examples. The functionality described above is applicable even for conditions of transmission loss different to those in the examples at the bottom of  FIG. 2  or at the top of  FIG. 3 . The average physical quantity computed by the control section  110  as illustrated at the bottom of  FIG. 3  may also differ according to changes in the conditions of transmission loss. The processing described above may also be implemented using Brillouin optical time domain reflectometry (BOTDR). 
     Explanation follows regarding a flow of operation when computing the averages for the physical quantity in the optical fiber sensor system.  FIG. 4  is a diagram to explain an example of a flow of operation of the optical fiber sensor system according to the first exemplary embodiment, as far as computation of the average physical quantity. 
     Refer now to  FIG. 4 . The light source section  120  first introduces the input light into the optical fiber  210  via the circulator  130  (S 1101 ). The light reception section  140  then measures intensity of the scattered light generated inside the optical fiber  210 , after the scattered light has passed through the circulator  130  (S 1102 ). The control section  110  then computes a physical quantity for the total length A1 of the optical fiber  210  from the intensity of the scattered light measured at step S 1102  (S 1103 ). The control section  110  then averages the physical quantity for each of the measurement lengths D using the physical quantity computed at step S 1103  (S 1104 ). Finally, taking the length A2 obtained by subtracting the measurement lengths D from the total length A1 of the optical fiber  210  as a new optical fiber length, the control section  110  obtains a relationship of the physical quantity to the distance from the optical fiber sensor device  10  (S 1105 ), and ends operation of the optical fiber sensor system. 
     2. SECOND EXEMPLARY EMBODIMENT 
     Explanation has been given regarding a first exemplary embodiment of the present disclosure. Next, explanation follows regarding a second exemplary embodiment of the present disclosure. Duplicate content to that described in the first exemplary embodiment will be omitted, with explanation focusing on differences to the first exemplary embodiment. Explanation follows regarding an example employing Brillouin optical time-domain reflectometry (BOTDR), this being sensing technology for measuring frequency spectra of Brillouin-scattered light. 
     In the second exemplary embodiment, the amounts of a moisture-sensitive material provided on an outer peripheral face of the optical fiber at measurement locations are adjusted so as to make reception sensitivities at plural measurement locations substantially the same as each other, thereby facilitating comparison of measurement results at the plural measurement locations. 
       FIG. 5  is a diagram to explain an example of the measurement locations  220  according to the second exemplary embodiment.  FIG. 5  illustrates a hollow pipe P, a moisture-sensitive material H, and a segment of an optical fiber  210 . The moisture-sensitive material H is wound around a circular columnar face of the hollow pipe P. The moisture-sensitive material H is a substance that expands as humidity rises. The expansion ratio of the moisture-sensitive material H is determined by the humidity expansion coefficient specific to the moisture-sensitive material H. 
     The optical fiber sensor in  FIG. 5  is capable of measuring the value of strain in response to humidity. The following is a specific explanation thereof. First, the moisture-sensitive material H expands as humidity rises. The optical fiber  210  wound around the moisture-sensitive material H is applied with pressure when the moisture-sensitive material H expands, generating strain. Namely, the optical fiber sensor device  10  is able to measure humidity indirectly by employing the moisture-sensitive material H. 
     For a certain size of hollow pipe P, an increase in the volume of the moisture-sensitive material H provided to the circular columnar face of the hollow pipe P will, for example, generally result in a larger increase in the volume of the moisture-sensitive material H for the same rise in humidity. This larger increase in volume causes a greater increase in the value of strain in the optical fiber  210 . Increasing the volume of the moisture-sensitive material H will accordingly increase the value of strain in a segment of the optical fiber  210  for the same rise in humidity. For example, when employing BOTDR in an optical fiber sensor system, since a shift in the frequency of Brillouin scattering caused by strain is measured, the fiber sensor sensitivity is raised by increasing the value of strain in the optical fiber  210  for the same rise in humidity. 
     The shape of the hollow pipe P does not have to be a circular columnar body as illustrated in  FIG. 5 , and the hollow pipe P may be cuboidal, for example. Moreover, configuration may employ the moisture-sensitive material H alone, without using a hollow pipe P. 
     Explanation follows regarding adjustment of the amount of coating of the moisture-sensitive material H, with reference to an example in which the moisture-sensitive material H is coated onto a circular columnar face of a circular columnar body.  FIG. 6  is a diagram to explain an example of a method for computing a compensated amount for the moisture-sensitive material H according to the second exemplary embodiment.  FIG. 6  illustrates a cross-section of the circular columnar body illustrated in  FIG. 5 .  FIG. 6  illustrates the hollow pipe P and the moisture-sensitive material H. 
     In  FIG. 6 , the radius of the hollow pipe P is denoted r (m). The humidity expansion coefficient of the moisture-sensitive material H is denoted X (ppm/% RH), and the thickness of the moisture-sensitive material H prior to a rise in humidity is denoted Z1 (m). Thus, the outer circumference prior to a rise in humidity is 2π (r+Z1) (m). 
     The thickness Z2 (m) of the moisture-sensitive material H after the rise in humidity is given under the above conditions by Z2=Z1 (1+XY), wherein Y (%) is the humidity rise. The proportional strain c induced thereby is computed using the following Equation (1). 
     
       
         
           
             
               
                 
                   
                     
                       
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     Namely, the relationship between the proportional strain c and the rise in humidity Y is determined by setting the humidity expansion coefficient X, the thickness Z1 of the moisture-sensitive material H prior to humidity rise, and the radius r of the hollow pipe P. Accordingly, the amount by which the frequency of the scattered light shifts in response to the rise in humidity Y can be computed using Equation (2) below, wherein a shift in frequency of scattered light with respect to the proportional strain is denoted P (MHz/με). 
     
       
         
           
             
               
                 
                   
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     Namely, since the sensitivity of the optical fiber sensor can be raised by increasing the value of strain in the optical fiber  210  for the same rise in humidity, the thickness Z1 of the moisture-sensitive material is set thicker at a location where there is a long distance from the optical fiber sensor device  10  than the thickness Z1 of the moisture-sensitive material at a location where there is a short distance therefrom. 
     Although explanation has been given regarding a method for computing the thickness of the moisture-sensitive material, this is merely an example thereof. The method for computing the required compensated amount, namely the volume of the moisture-sensitive material H, will vary depending on the type and shape etc. of the moisture-sensitive material H. Moreover, the method for computing the required compensated amount will also vary depending on circumstances at the respective measurement locations  220  and on the method employed to install the optical fiber  210  and the like. 
     This functionality enables the reception sensitivities at the plural measurement locations to be adjusted so as to be substantially the same as each other. 
     3. HARDWARE CONFIGURATION EXAMPLE 
     Explanation follows regarding an example of a hardware configuration of the optical fiber sensor device  10  according to an exemplary embodiment of the present invention.  FIG. 7  is a block diagram illustrating an example of hardware configurations for configurations according to an exemplary embodiment of the present disclosure. Refer now to  FIG. 7 . The optical fiber sensor device  10  includes, for example, a CPU  371 , ROM  372 , RAM  373 , a host bus  374 , a bridge  375 , an external bus  376 , an interface  377 , an input section  378 , an output section  379 , a storage section  380 , a drive  381 , a connection port  382 , and a communication section  383 . The hardware configuration illustrated is an example, and some configuration elements may be omitted therefrom. Alternatively, configuration elements other than those illustrated may also be included in addition thereto. 
     CPU  371   
     The CPU  371  functions as, for example, a computation processing device or a control device, and controls all or some of the operation of the respective configuration elements based on various programs recorded in the ROM  372 , the RAM  373 , the storage section  380 , or a removable recording medium  501 . 
     ROM  372 , RAM  373   
     The ROM  372  holds programs to be read by the CPU  371 , and data and the like employed in computation. The RAM  373  temporarily or permanently holds programs to be read by the CPU  371 , and various parameters and the like that are changed as appropriate during execution of these programs. 
     Host Bus  374 , Bridge  375 , External Bus  376 , Interface  377   
     The CPU  371 , the ROM  372 , and the RAM  373  are, for example, connected together through the host bus  374  having high speed data transmission capabilities. The host bus  374  is, for example, connected across the bridge  375  to the external bus  376  having a comparatively slow data transmission speed. The external bus  376  is connected to the various configuration elements through the interface  377 . 
     Input Section  378   
     A mouse, keyboard, touch panel, button, switch, microphone, lever, or the like is, for example, employed as the input section  378 . A remote controller capable of transmitting control signals using infrared or another form of electromagnetic waves may be employed as the input section  378 . 
     Output Section  379   
     The output section  379  is a device capable of visually or audibly notifying a user of acquired information, and is for example a display device (display unit) such as a cathode ray tube (CRT), an LCD, an organic EL display, or the like, an audio output device such as a speaker, headphone, or the like, a printer, a mobile telephone, or a fax machine. 
     Storage Section  380   
     The storage section  380  is a device used to hold various data. The storage section  380  employs, for example, a magnetic storage device such as a hard disk drive (HDD), a semiconductor storage device, an optical storage device, or a magneto-optical storage device. 
     Drive  381   
     The drive  381  is a device that reads information recorded on the removable recording medium  501 , for example a magnetic disk, optical disk, magneto-optical disk, semiconductor memory, or the like, and writes information to the removable recording medium  501 . 
     Removable Recording Medium  501   
     Examples of the removable recording medium  501  include DVD media, Blu-ray (registered trademark) media, HD-DVD media, and various semiconductor storage media. The removable recording medium  501  may obviously also be configured by an IC card containing a contactless IC chip, an electronic device, or the like. 
     Connection Port  382   
     The connection port  382  is a port used to connect an externally connected device  502 , for example a universal serial bus (USB) port, an IEEE 1394 port, a small computer system interface (SCSI), an RS-232C port, or an optical-audio terminal. 
     Externally Connected Device  502   
     The externally connected device  502  is, for example, a printer, a portable music player, a digital camera, a digital video camera, an IC recorder, or the like. 
     Communication Section  383   
     The communication section  383  is a communication device used to connect to a network  503 . Examples of the communication section  383  include communication cards for a wired or wireless LAN, Bluetooth (registered trademark), or a wireless USB (WUSB), an optical communication router, an asymmetric digital subscriber line (ADSL) router, or a modem for various communications. The communication section  883  may also connect to a telephone network such as an internal telephone network or a mobile telephone operator network. 
     4. CONCLUSION 
     As described above, the present disclosure enables the provision of a novel and improved optical fiber sensor device and optical fiber sensor system capable of making the reception sensitivities substantially the same for plural measurement locations, thereby facilitating comparison of measurement results between the plural measurement locations. 
     Although detailed explanation has been given regarding preferable exemplary embodiments of the present disclosure with reference to the appended drawings, the present disclosure is not limited to these examples. It would be obvious to a person of ordinary skill in the technical field of this disclosure that various modifications and amendments could be arrived at within the range of the technical concept recited in the scope of claims, and it should be understood that such modifications and amendments would obviously also fall within the technical scope of the present disclosure.