JP4035758B2 - Motion detection sensor and photodetector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention in one or more locations, but about the operation detection sensor and a light detector for detecting the target of the water level or water pressure detecting whether a predetermined value or more.
[0002]
[Prior art]
There is a water level detector as an example of a prior art device that detects the water level and water pressure. As this water level detector, there are generally known ones that mechanically and electrically detect the position of the float, and those that optically detect the water level itself and convert it into an electrical signal. However, these water level detectors have various problems such as many mechanically movable parts causing failure, and it is necessary to install a battery near the water level detector in order to secure the power supply of the electric circuit. .
[0003]
As another example of the water level detector, as shown in FIGS. 7 and 8, the change in float buoyancy is applied to an optical fiber Bragg grating (hereinafter abbreviated as Fiber Bragg Grating, abbreviated as FBG). An optical water level detector that measures the water level by transmitting is known. A water level detector including such an FBG will be described with reference to the drawings. 7 and 8 are configuration diagrams of a water level detector according to the prior art.
[0004]
As shown in FIG. 7, the water level detector includes a detection cell 114, a float 115, a diaphragm 116, a shaft 117, a block 118, an FBG 119, a lower limit stopper 120, an upper limit stopper 121, a linear guide 122, and an arm 123.
[0005]
This water level detector transmits the movement of buoyancy acting on the float 115 as the water level changes to the FBG 119 through the shaft 117 and the arm 123 connected and fixed to the float 115, and detects the water level change as a wavelength change of the FBG 119. It is.
[0006]
Here, as is well known, the FBG 119 is a region in which the refractive index of the core of the optical fiber is periodically changing along the optical axis, and narrow band light centered on a specific wavelength according to the refractive index. Has the property of reflecting. In addition, since the refractive index of the core changes according to the strain applied to the optical fiber and the ambient temperature, by detecting the wavelength change of the reflected light from the FBG, the presence or absence of the distortion or temperature change, its size, etc. Can be detected.
[0007]
A method for manufacturing such an FBG will be described. FBG is a part where UV light interferes with a germanium-doped single mode fiber that has been irradiated with UV light on a phase mask with a phase grating and interfered with UV light using the phase mask, and the coating is removed and the cladding is exposed. By exposing to light, the refractive index of the interfering portion increases and periodic refractive index modulation is formed.
[0008]
Then, each part of the water level detector of a prior art is demonstrated. The float 115 is fixed to the center of the diaphragm 116. The periphery of the diaphragm 116 is fixed to the detection cell 114 by a method of ensuring airtightness by means such as electron beam welding.
[0009]
The shaft 117 connected to the diaphragm 116 is constrained to move only in the vertical direction by the linear guide 122, and moves up and down in conjunction with the float 115 that moves up and down according to the water level. An arm 123 is fixed to the shaft 117, and one end of the FBG 119 is fixed to the arm 123. The other end of the FBG 119 is fixed to the block 118 fixed to the detection cell 114.
[0010]
Further, the lower limit stopper 120 and the upper limit stopper 121 are fixed inside the detection cell 114 in order to restrain the vertical movement of the shaft 117. Regarding the fixing, as shown in FIG. 7, when the water level is as low as W1 and the buoyancy is not acting on the float 115 and the arm 123 fixed to the shaft 117 is in contact with the lower limit stopper 120, the FBG 119 Is fixed to be natural length.
[0011]
In a state where the buoyancy is not applied to the float 115 and the arm 123 and the lower limit stopper 120 are in contact with each other, the diaphragm 116 is extended due to the weight of the float 115 and the shaft 117.
On the other hand, when the float 115 receives buoyancy and the arm 123 and the upper limit stopper 121 are in contact with each other, the diaphragm 116 is not deformed. The diaphragm 116 is provided in this way.
[0012]
Then, the water level detection by such a water level detector is demonstrated.
As shown in FIG. 7, when the buoyancy is not exerted on the float 115 because the water level is at the level of W1, the FBG 119 has a natural length, so that no distortion occurs in the FBG 119. Although the dead weight of the float 115 and the shaft 117 acts on the diaphragm 116, a situation in which an excessive force is applied to the diaphragm 116 due to the contact between the lower limit stopper 120 and the arm 123 is avoided.
[0013]
On the other hand, as shown in FIG. 8, when the water level changes and reaches the level of W2, buoyancy acts on the float 115. When the float 115 moves upward due to this buoyancy, the FBG 119 is stretched. However, since the upward movement of the shaft 117 is restricted by the upper limit stopper 121, a situation in which the shaft 117 moves beyond a predetermined distance does not occur.
[0014]
Further, when the water level returns to W1, the force by which the FBG 119 attempts to return to the natural length and the own weight of the shaft 117 and the float 115 are applied, so that the lower limit stopper 120 and the arm 123 come back to contact with each other. Such an operation is repeated by a change in the water level (movement between W1 and W2).
When the water level becomes W2, the FBG 119 is extended so that the specific wavelength of the reflected light of the FBG 119 changes from the short wavelength to the long wavelength, so that it is detected that the water pressure or the water level has exceeded the set value. be able to. Prior art water level detectors were such.
[0015]
Next, a long-period grating, which is a type of FBG, will be described as a related art example related to FBG with reference to the drawings. FIG. 9 is a configuration diagram of the long-period grating, and FIGS. 10 and 11 are output characteristic diagrams from the long-period grating.
A long-period grating, which is a kind of FBG, is a transmissive filter with a period of periodic refractive index modulation of the order of 100 microns.
[0016]
Such long-period gratings have been published in papers such as S. Savin, MJFDigonnet, GSKino, and HSShaw: “Tunable mechanically induced long-period fiber gratings”, Optics Letters, Vol. 25, No. 10 ( May 15, 2000), an example in which a long-period grating is configured by sandwiching a normal single-mode optical fiber for communication between a V-groove array and a plate is reported.
[0017]
Specifically, as shown in FIG. 9, the long-period grating includes a V-groove array 130, an optical fiber 131, and a plate 132.
In the V-groove array 130, a diffraction surface composed of a plurality of V-grooves is formed on the optical fiber 131 side. The optical fiber 131 is a normal single mode fiber. The plate 132 presses and fixes the optical fiber 131 to the V-groove array 130 side.
[0018]
In such a long period grating, when a load is applied from above the V-groove array 130, a loss occurs at a specific wavelength. The loss of the specific wavelength has a filter transmission amount characteristic as shown in FIG. When the load is P ₁ , P ₂ , P ₃ , P ₄ , P _{5 in} order from the smallest, the load P ₄ , P ₅ has a characteristic that the loss is particularly large.
[0019]
Further, as shown in FIG. 11, the light propagation direction of the optical fiber 131 is changed by changing the angle between the direction in which the optical fiber 131 extends and the direction in which the V-groove formed in the lattice plane of the V-groove array 130 extends. Since the periodic interval of the V-groove array 130 changes, the specific wavelength to be lost can be made variable. FIG. 11 shows the amount of transmission of the filter when a specific wavelength is lost such that the periodic intervals of the V-groove array 130 are 683 μm, 703 μm, 712 μm and 722 μm.
[0020]
[Problems to be solved by the invention]
In addition to the above-mentioned conventional technology, a plurality of FBGs having different reflected light wavelengths are connected in series to one optical fiber to multiplex the reflected light wavelengths of the FBGs and measure a plurality of locations. It is possible to construct a system.
However, connecting such a plurality of FBGs in series is not an easy task.
[0021]
Specifically, as described above, since a plurality of FBG reflection wavelengths are set in advance and a plurality of FBGs are provided for one optical fiber, a plurality of phase masks must be manufactured for each FBG. In addition, the manufacturing of the sensor is complicated such that it is necessary to individually incorporate the FBG, and it is difficult to reduce the manufacturing cost due to this.
[0022]
Also, in this system using FBG, the wavelength of reflected light from FBG is measured, so when trying to construct a long-distance / multi-point measurement system, the extinction ratio of reflected light decreases due to backscattering of the optical fiber, etc. For this reason, there are disadvantages such as a decrease in measurement accuracy.
[0023]
The present invention has been made to solve the above-mentioned problems, and its purpose is to use a long-period grating to perform a novel operation that can be measured at one or more locations and realize a long-distance system. It is to provide a detection sensor and a photodetector.
[0024]
[Means for Solving the Problems]
The motion detection sensor according to the first aspect of the present invention that solves the above problems is
A V-groove array in which a diffractive surface by the V-groove is formed;
A plate having a flat pressing surface, the pressing surface being arranged to face the diffractive surface of the V-groove array;
A shaft fixed to the plate;
A linear guide that supports the shaft so as to move the plate up and down in order to separate the pressing surface of the plate toward the diffractive surface of the V-groove array;
An optical fiber disposed between the V-groove array and the plate ;
With
The plate is adapted to move with the height contacting the optical fiber supported by the V-groove array as a top dead center and the height contacting the linear guide as a bottom dead center, and through the shaft. According to the detected object to be transmitted, it is separated from the optical fiber,
When the optical fiber is sandwiched between the V-groove array and the plate by the movement of the plate, the optical fiber emits light with a specific wavelength lost to detect a change in the operation of the detection target. And
[0025]
Moreover, the photodetector which concerns on invention of Claim 2 similarly is,
A motion detection sensor according to claim 1;
A detection cell that protects the motion detection sensor disposed inside from an external environment;
A float that floats on the surface of the water and moves up and down according to the water level;
Thereby sealing the inside of the detection cell, and wherein the shaft and the the state in which the stretching force is added to the float, diaphragm Ru raises and lowers the shaft within the detection cell so as to follow the vertical movement of the float,
With
Detecting a water level in the case where there is no light loss in a specific wavelength there is a gap is emitted from the optical fiber between the V-groove array and the plate of the motion detection sensor is less than a predetermined value, also, and detecting the water level exceeds a predetermined value when the light with the V-groove array and the plate there is a loss of a specific wavelength by sandwiching close contact with the optical fiber is emitted from the optical fiber.
[0026]
Moreover, the photodetector which concerns on invention of Claim 3 similarly is,
A motion detection sensor according to claim 1;
A detection cell that protects the motion detection sensor disposed inside from an external environment;
Thereby sealing the inside of the detection cell, and while applying a stretching force to said shaft, a diaphragm Ru raises and lowers the shaft within said detection cell being driven by the displacement by the pressure detection,
With
Detecting a pressure in the case where there is no light loss in a specific wavelength there is a gap is emitted from the optical fiber between the V-groove array and the plate of the motion detection sensor is less than a predetermined value, also, and detecting when the pressure exceeds a predetermined value when the light with the V-groove array and the plate there is a loss of a specific wavelength by sandwiching close contact with the optical fiber is emitted from the optical fiber.
[0027]
Similarly, the motion detection sensor according to the invention of claim 4
A plurality of the motion detection sensors according to claim 1 are arranged, and a single optical fiber is used in common, and the plurality of V-groove arrays formed at the same cycle in each motion detection sensor By making the inclination angles different from each other, the light having a plurality of specific wavelengths lost from the one optical fiber is emitted,
When the optical fiber is sandwiched between the V-groove array and the plate due to the movement of the plate, the optical fiber emits light having a plurality of different specific wavelengths corresponding to the inclination angle, and is different from each other. It is characterized by performing distributed sensing for detecting a change in the operation of the detection target .
[0028]
Similarly, the photodetector according to the invention of claim 5 is:
A plurality of the photodetectors according to claim 2 are arranged, and a single optical fiber is used in common , and the plurality of V-groove arrays formed at the same cycle in each photodetector. By making the inclination angles different from each other, the light having a plurality of specific wavelengths lost from the one optical fiber is emitted,
When the optical fiber is sandwiched between the V-groove array and the plate due to the movement of the plate, the optical fiber emits light having a plurality of different specific wavelengths corresponding to the inclination angle, and is different from each other. It is characterized by performing distributed sensing to detect water level changes .
[0029]
Similarly, the photodetector according to the invention described in claim 6 includes a plurality of the photodetectors described in claim 3 , and uses one optical fiber in common , and is the same in each photodetector. The plurality of V-groove arrays formed at a period of different from each other so as to emit light having a plurality of specific wavelengths lost from the one optical fiber by making the inclination angles different from each other. West,
When the optical fiber is sandwiched between the V-groove array and the plate due to the movement of the plate, the optical fiber emits light having a plurality of different specific wavelengths corresponding to the inclination angle, and is different from each other. It is characterized by performing distributed sensing for detecting a change in pressure .
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described. The present embodiment includes the motion detection sensor according to claim 1, and is a photodetector according to claim 2. Specifically, it is an optical water level detector that is installed near the water surface of a sewer or the like and detects the water level. Hereinafter, a description will be given with reference to FIGS. 1 and 2 are configuration diagrams of the optical water level detector according to the first embodiment of the present invention.
[0032]
As shown in FIG. 1, the optical water level detector includes an optical fiber 1, a V-groove array 2, a detection cell 3, a plate 4, a linear guide 5, a shaft 6, a diaphragm 7, and a float 8.
Here, the optical fiber 1, the V groove array 2, the plate 4, and the shaft 6 (one specific example of the moving means) constitute an operation detection sensor. This motion detection sensor is housed inside the detection cell 4. The sensor function by the motion detection sensor will be described later.
[0033]
The optical fiber 1 is a single mode optical fiber and is disposed so as to pass between the V-groove array 2 and the plate 4. The V-groove array 2 is fixed in the detection cell 4, but the plate 4 is connected to the shaft 6. The shaft 6 is supported by a linear guide 5 and the moving direction is restricted only in the vertical direction. That is, the plate 4 is configured to move. A float 8 is connected to the shaft 6 via a diaphragm 7. The float 8 moves up and down in conjunction with the vertical movement of the shaft 6.
[0034]
Although not shown in FIG. 1, a white light source (broadband light source) is connected on the incident side of the optical fiber 1, and transmitted light from an optical spectrum analyzer or the like is received on the output side of the optical fiber 1. A wavelength detection unit for detecting the transmission center wavelength and loss is connected.
[0035]
Next, the operation of the optical water level detector of this embodiment will be described. Now, when the water level is below the float 8 and no buoyancy is acting on the float 8 as shown by W1 in FIG. 1, the weight of the plate 4, the shaft 6 and the float 8 exceeds the extension force of the diaphragm 7. The plate 4, the shaft 6 and the float 8 all move downward. The plate 4 is in contact with the linear guide 5 and stops at the bottom dead center. In this way, the vertical movement of the float 8 is restricted, so that an excessive tension is not applied to the diaphragm 7.
[0036]
In the motion detection sensor when stopped at the bottom dead center, the optical fiber 1 is not sandwiched and adhered to the V-groove array 2 and the plate 4, so that a loss of a specific wavelength does not occur. Operates as a fiber. Therefore, the white light incident from the optical fiber 1 is output as it is.
As described above, while the plate 4 does not contact the V-groove array 2, the optical fiber 1 operates as a normal communication optical fiber.
[0037]
Thereafter, when the water level rises and buoyancy acts on the float 8 to reverse the above-described force relationship, the plate 4, the shaft 6 and the float 8 all rise, and as shown in FIG. After reaching the fixed V-groove array 2, the optical fiber 1 is sandwiched and adhered between the V-groove array 2 and the plate 4, and the optical fiber 1 is equal to the periodic interval of the V-groove array 2 and is subjected to a periodic load. .
[0038]
In this case, as described in the conventional long-period grating, the refractive index of the portion of the optical fiber 1 to which distortion is applied is increased by the photoelastic effect. This increase in refractive index forms a periodic refractive index distribution in proportion to the periodic interval of the V-groove array 2, thereby forming an optical fiber type filter similar to the long-period grating of the prior art.
[0039]
At this time, when white light incident from the incident side of the optical fiber 1 passes through an optical fiber type filter formed by the V-groove array 2, light having a specific wavelength proportional to the periodic interval of the V-groove array 2 is lost. Light from which the specific wavelength is lost is transmitted and output from the emission side of the optical fiber 1. Therefore, if the loss of the specific wavelength of the transmitted light is always detected by the optical wavelength detector disposed on the output side of the optical fiber 1, it is possible to detect whether the water level has become W2 or higher.
[0040]
That is, the optical water level detector of the present embodiment has a water level below a predetermined value when light having a gap between the V-groove array 2 and the plate 4 and having no specific wavelength loss is emitted from the optical fiber 1. It is detected that the water level exceeds a predetermined value when the V-groove array 2 and the plate 4 sandwich and closely contact the optical fiber 1 and light having a specific wavelength loss is emitted from the optical fiber 1. .
[0041]
According to the optical water level detector having the configuration and function as described above, the configuration is simpler than that of the prior art, and the manufacturing cost can be reduced.
The optical water level detector of the first embodiment is such.
[0042]
Subsequently, a second embodiment of the present invention will be described. The present embodiment includes the motion detection sensor according to claim 1, and is a photodetector according to claim 3. Specifically, it is an optical water pressure detector that is installed on the surface of a sewer or the like and detects the water pressure. Hereinafter, a description will be given with reference to FIGS. 3 and 4 are configuration diagrams of the optical water pressure detector according to the second embodiment of the present invention.
[0043]
As shown in FIG. 3, the optical water pressure detector includes an optical fiber 1, a V groove array 2, a detection cell 3, a plate 4, a linear guide 5, a shaft 6, and a diaphragm 7. Here, the optical fiber 1, the V groove array 2, the plate 4, and the shaft 6 (one specific example of the moving means) constitute an operation detection sensor. This motion detection sensor is housed inside the detection cell 4.
This optical water pressure detector has the same components as those in the first embodiment except that the float 8 is removed from the optical water level detector described in the first embodiment, and redundant description is omitted. .
[0044]
In the optical water pressure detecting device of the present embodiment, the diaphragm 7 is deformed by the water head pressure, so that the water pressure can be measured.
When the water pressure is low, the weight of the plate 4 and the shaft 6 exceeds the extension force of the diaphragm 7, so that both the plate 4 and the shaft 6 move downward, the plate 4 comes into contact with the linear guide 5, and at the bottom dead center. It has stopped.
[0045]
In such a state, since the optical fiber 1 is not sandwiched and adhered between the V-groove array 2 and the plate 4, the loss of a specific wavelength does not occur and the optical fiber 1 operates as a normal communication optical fiber. Therefore, the white light incident from the optical fiber 1 is output from the emission side as it is.
As described above, while the plate 4 does not contact the V-groove array 2, the optical fiber 1 operates as a normal communication optical fiber.
[0046]
Thereafter, when the pressure is applied to the diaphragm 7 due to the pressure increase and the above-described force relationship is reversed, both the plate 4 and the shaft 6 are lifted, and as shown in FIG. 4, the V-groove fixed at the top dead center. Upon reaching the array 2, the optical fiber 1 is sandwiched and adhered between the V-groove array 2 and the plate 4. In this case, a periodic load is applied to the optical fiber 1 which is equal to the periodic interval of the V-groove array 2. Then, light with a specific wavelength lost is output from the emission side of the optical fiber 1.
[0047]
That is, the optical water pressure detector of the present embodiment has a water pressure of a predetermined value or less when light having a gap between the V groove array 2 and the plate 4 and having no loss of a specific wavelength is emitted from the optical fiber 1. It is detected that the water pressure exceeds a predetermined value when the V-groove array 2 and the plate 4 sandwich and closely contact the optical fiber 1 and light having a loss of a specific wavelength is emitted from the optical fiber 1. .
[0048]
According to the optical water pressure detector having the configuration and function as described above, the configuration is simpler than that of the prior art, and the manufacturing cost can be reduced.
The light pressure detector of the second embodiment is such.
[0049]
Subsequently, a third embodiment of the present invention will be described. The present embodiment includes the motion detection sensor according to claim 4, and is a photodetector according to claim 5. Specifically, it is an optical water level detector that is installed near the surface of the water such as a sewer and detects the water level at a plurality of locations . Below, it will be described collectively with reference to FIG. FIG. 5 is a configuration diagram of an optical water level detector according to the third embodiment of the present invention.
[0050]
In the present embodiment, as shown in FIG. 5, a plurality of optical water level detectors described as the first embodiment are arranged at different positions, and light formed as a system using a single optical fiber 1 in common. It is a water level detector. In this optical water level detector, the inclination angle of the V-groove array 2 with respect to the optical fiber 1 is all made different for each optical water level detector, and light with a plurality of specific wavelengths lost depending on the detection location is output. A change in the water level can be detected by specifying the detected location.
[0051]
For example, referring to the characteristic diagram of FIG. 10, if the period of one V-groove array 2 in FIG. 5 is inclined so as to be 683 μm, light of about 1534 nm is lost and the other V-groove array is lost. If it is inclined so that the period of 2 is 712 μm, light of about 1560 nm is lost. By detecting the occurrence of such two specific wavelength losses with the optical wavelength detector provided on the output side of the optical fiber 1, changes in the water level are detected by optical water level detectors arranged at two different locations. can do. The optical water level detector of the third embodiment is like this.
[0052]
Subsequently, a fourth embodiment of the present invention will be described. The present embodiment includes the motion detection sensor according to claim 4, and is a photodetector according to claim 6. Specifically, it is an optical water pressure detector that is installed near the water surface of a sewer or the like and detects water pressure at a plurality of locations . Below, it will be described collectively with reference to FIG. FIG. 6 is a configuration diagram of the optical water pressure detector according to the fourth embodiment of the present invention.
[0053]
In this embodiment, as shown in FIG. 6, a plurality of optical water pressure detectors described as the second embodiment are arranged at different positions, and light formed as a system using one common optical fiber 1. It is a water pressure detector. In this optical water pressure detector, the inclination angles of the V-groove array 2 with respect to the optical fiber 1 are all made different for each optical water pressure detector, and light with a plurality of specific wavelengths lost depending on the detection location is output. For this reason, it is made possible to detect the water pressure change by specifying the detected part. This embodiment is the same as the operation of the optical water level detector described in the third embodiment, and the description thereof is omitted. The fourth embodiment is like this.
[0054]
According to the invention described above, a long-period grating using a V-groove array and a plate is employed in place of the conventional FBG formed by the interference of ultraviolet rays. Furthermore, in the past, the groove direction of the V-groove array was only orthogonal to the optical fiber. However, in the present invention, the transmission center wavelength is made variable by changing the inclination appropriately as desired, and any specific wavelength is lost. Thus, fine adjustment of the sensor was made possible.
[0055]
Further, with respect to a single optical fiber, it is possible to connect a plurality of motion detection sensor with different respective angles of the V-groove of the V-groove array with respect to the optical fiber, the series connection can be a low-cost distribution type optical The detector can be constructed.
Furthermore, since the optical fiber is a normal optical fiber when the apparatus is not operating, the transmission distance of the sensor can be made longer than that of a sensor system using a normal FBG, and a long-distance photodetector can be constructed. .
Furthermore, since there is no need to secure a power source near the detector, there are excellent effects such as no choice of installation location.
[0056]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a novel motion detection sensor and photodetector that can measure at one or two or more locations by using a long period grating and realize a long distance system.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an optical water level detector according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram of an optical water level detector according to the first embodiment of the present invention.
FIG. 3 is a configuration diagram of an optical water pressure detector according to a second embodiment of the present invention.
FIG. 4 is a configuration diagram of an optical water pressure detector according to a second embodiment of the present invention.
FIG. 5 is a configuration diagram of an optical water level detector according to a third embodiment of the present invention.
FIG. 6 is a configuration diagram of an optical water pressure detector according to a fourth embodiment of the present invention.
FIG. 7 is a block diagram of a conventional water level detector.
FIG. 8 is a configuration diagram of a conventional water level detector.
FIG. 9 is a configuration diagram of a long-period grating.
FIG. 10 is an output characteristic diagram from a long-period grating.
FIG. 11 is an output characteristic diagram from a long-period grating.
[Explanation of symbols]
1 Optical fiber 2 V-groove array 3 Detection cell 4 Plate 5 Linear guide 6 Shaft 7 Diaphragm 8 Float

Claims (6)

A V-groove array in which a diffractive surface by the V-groove is formed;
A plate having a flat pressing surface, the pressing surface being arranged to face the diffractive surface of the V-groove array;
A shaft fixed to the plate;
A linear guide that supports the shaft so as to move the plate up and down in order to separate the pressing surface of the plate toward the diffractive surface of the V-groove array;
An optical fiber disposed between the V-groove array and the plate ;
With
The plate is adapted to move with the height contacting the optical fiber supported by the V-groove array as a top dead center and the height contacting the linear guide as a bottom dead center, and through the shaft. According to the detected object to be transmitted, it is separated from the optical fiber,
When the optical fiber is sandwiched between the V-groove array and the plate by the movement of the plate, the optical fiber emits light with a specific wavelength lost to detect a change in the operation of the detection target. The motion detection sensor. A motion detection sensor according to claim 1;
A detection cell that protects the motion detection sensor disposed inside from an external environment;
A float that floats on the surface of the water and moves up and down according to the water level;
Thereby sealing the inside of the detection cell, and wherein the shaft and the the state in which the stretching force is added to the float, diaphragm Ru raises and lowers the shaft within the detection cell so as to follow the vertical movement of the float,
With
Detecting a water level in the case where there is no light loss in a specific wavelength there is a gap is emitted from the optical fiber between the V-groove array and the plate of the motion detection sensor is less than a predetermined value, also, light detection and detecting a water level in the case where light with the V-groove array and the plate there is a loss of a specific wavelength by sandwiching close contact with the optical fiber is emitted from the optical fiber exceeds a predetermined value vessel. A motion detection sensor according to claim 1;
A detection cell that protects the motion detection sensor disposed inside from an external environment;
Thereby sealing the inside of the detection cell, and while applying a stretching force to said shaft, a diaphragm Ru raises and lowers the shaft within said detection cell being driven by the displacement by the pressure detection,
With
Detecting a pressure in the case where there is no light loss in a specific wavelength there is a gap is emitted from the optical fiber between the V-groove array and the plate of the motion detection sensor is less than a predetermined value, also, light detection and detecting a pressure in the case where light with the V-groove array and the plate there is a loss of a specific wavelength by sandwiching close contact with the optical fiber is emitted from the optical fiber exceeds a predetermined value vessel. A plurality of the motion detection sensors according to claim 1 are arranged, and a single optical fiber is used in common, and the plurality of V-groove arrays formed at the same cycle in each motion detection sensor By making the inclination angles different from each other, the light having a plurality of specific wavelengths lost from the one optical fiber is emitted,
When the optical fiber is sandwiched between the V-groove array and the plate due to the movement of the plate, the optical fiber emits light having a plurality of different specific wavelengths corresponding to the inclination angle, and is different from each other. A motion detection sensor that performs distributed sensing to detect a motion change of a detection target . A plurality of the photodetectors according to claim 2 are arranged, and a single optical fiber is used in common , and the plurality of V-groove arrays formed at the same cycle in each photodetector. By making the inclination angles different from each other, the light having a plurality of specific wavelengths lost from the one optical fiber is emitted,
When the optical fiber is sandwiched between the V-groove array and the plate due to the movement of the plate, the optical fiber emits light having a plurality of different specific wavelengths corresponding to the inclination angle, and is different from each other. A photodetector that performs distributed sensing to detect changes in water level . A plurality of the photodetectors according to claim 3 are arranged, and a single optical fiber is used in common , and the plurality of V-groove arrays formed at the same cycle in each photodetector. By making the inclination angles different from each other, the light having a plurality of specific wavelengths lost from the one optical fiber is emitted,
When the optical fiber is sandwiched between the V-groove array and the plate due to the movement of the plate, the optical fiber emits light having a plurality of different specific wavelengths corresponding to the inclination angle, and is different from each other. A photodetector that performs distributed sensing to detect a change in pressure .

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