141 results about "Bend loss" patented technology

The embodiment of the utility model provides an optical fiber recognizer and an optical fiber recognition system, and belongs to the technical field of optical communication, the optical fiber recognizer comprises a vibration structure and a bending structure, an optical signal on an optical fiber firstly passes through the vibration structure and then passes through the bending structure, the vibration structure drives the optical fiber to reciprocate so as to repeatedly bend the optical fiber, and an optical signal with periodically changed optical power is generated. The bending structure drives part of the optical fiber to move to bend the optical fiber, and the variation of the optical power can be judged by detecting the light leakage amount caused by bending of the optical fiber. When the detector detects and identifies the periodically changing optical signal, online lossless identification of the optical fiber is realized, and the periodically changing optical signal is taken as a criterion, so that misjudgment can be avoided. According to the variable quantity of the optical power, feedback adjustment of the bending quantity of the optical fiber can be achieved, the bending quantity can be correspondingly adjusted according to optical fibers with different wire diameters and wavelengths, optical signals with certain optical power variable quantity and periodical change are generated, accurate lossless identification is achieved, and the risk of service interruption caused by too large bending loss is avoided.

The invention provides a multi-mode hollow-core anti-resonance optical fiber, and relates to the technical field of optical fibers, and the multi-mode hollow-core anti-resonance optical fiber comprises a hollow outer layer tube and a plurality of cladding capillary tubes arranged on the inner wall of the outer layer tube; each cladding capillary tube comprises a circular tube, an elliptical tube and an anti-resonance plate, and the elliptical tube is nested in the circular tube through the anti-resonance plate and is coaxially arranged with the circular tube. In the technical scheme provided by the invention, the elliptical tube is nested in the circular tube by the anti-resonance plate, and the elliptical tube and the circular tube are coaxially arranged, so that a nested integrated cladding capillary tube is formed, and the multi-mode hollow-core anti-resonance optical fiber with the structure can reduce bending loss and limiting loss of the fiber core in a high-order mode.

The invention discloses a communication optical cable online monitoring method based on GIS, and relates to the technical field of communication optical cable fault monitoring. The invention provides a communication optical cable online monitoring method based on GIS. In the process of analyzing the performance of the optical cable, the optical cable performance information corresponding to each monitoring section of the designated communication optical cable is collected, including bending loss, dispersion compensation value and optical power loss, so as to help fully understand the operation status of the optical cable, and then quickly locate and solve the problem, thereby avoiding service interruption caused by the degradation of optical fiber performance. In the process of analyzing the environment in which the optical cable is located, the environmental parameters corresponding to each monitoring section of the designated communication optical cable, such as electromagnetic interference intensity and chemical corrosion index, are obtained, which helps to evaluate the influence of the external environment on the stability of the optical cable, thereby reducing the threat of environmental factors to the performance of the optical cable, and taking protective measures in advance to extend the service life of the optical cable.

The utility model discloses a fixing device for processing a high-toughness communication optical cable, which comprises a supporting mechanism and a fixing mechanism arranged at the top of the supporting mechanism, the supporting mechanism comprises a top frame, the fixing mechanism comprises a mounting seat, and the center of the top of the mounting seat is in sliding connection with a limiting rod. The equipment has the advantages of stable clamping and convenient adjustment, and solves the problems that the fixing effect of part of fixing devices on optical cables is not ideal, adjustment cannot be carried out according to optical cables of different specifications, the optical cables which cannot be effectively fixed are prone to displacement or looseness under external environment changes (such as temperature, wind load and vibration), and the optical cables cannot be effectively fixed. In the prior art, faults such as micro-bending loss increase and connection point loosening may be generated, the overall reliability and the service life of an optical cable line are reduced, the whole fixing device may need to be replaced when optical cables of different sizes are replaced or maintained by a fixing device lacking of adjustability, and the engineering cost and complexity are increased.

The embodiment of the invention provides an anti-bending optical fiber and a production process thereof, and relates to the technical field of optical fibers. The first wrapping layer wraps the core layer; the gradient layer wraps the first wrapping layer; the second wrapping layer wraps the gradient layer; and the refractive indexes of the core layer, the first cladding, the gradient layer and the second cladding are gradually reduced in sequence. According to the bending-resistant optical fiber and the production process thereof provided by the embodiment of the invention, the problem of relatively large bending loss of the optical fiber in the prior art is solved.

The invention discloses a method for detecting bending loss of an optical fiber ribbon, comprising: configuring detection equipment; testing an initial loss value; testing the bending loss value, winding the portion between the two ends of the optical fiber ribbon on a round rod for no more than 10 turns to obtain the bending loss value of each optical fiber from a strain tester; determining the bending loss value of the optical fiber ribbon, selecting the maximum bending loss value of the strain from the bending loss value of each optical fiber obtained as the bending loss test value of the detected optical fiber ribbon; the beneficial effects are: the bending loss of multiple optical fibers in the optical fiber ribbon can be detected simultaneously, making the invention simple and easy to implement, and the bending state of the optical fiber can be accurately and repeatedly simulated to provide a basis for accurate testing; the maximum bending loss value under the same environment can also be reflected, with a better inclusive effect, so that the detection value is more accurate.

The invention discloses a double-layer waveguide 2 * 2 microring optical switch, an optical switch array thereof and an optical signal processing method, and belongs to the technical field of optical communication devices. Aiming at the technical problem that a traditional micro-ring optical switch is difficult to realize a large free spectral range and low-loss transmission at the same time, the invention provides an innovative structure combining a silicon nitride micro-ring resonator and an annular Bragg grating, and the outer side of the silicon nitride micro-ring resonator is nested with the annular Bragg grating; and a light field forbidden band is constructed to suppress a light field radiated outwards by the resonator, so that strong light field constraint is realized to remarkably reduce bending loss. A silicon-silicon nitride double-layer waveguide interlayer coupling technology is adopted, the lower layer is a silicon coupling waveguide, the upper layer is a silicon nitride micro-ring resonator and concentric annular grating structure, and a titanium nitride micro-heater is integrated to adjust the resonant wavelength. The invention effectively solves the technical problem that the silicon nitride micro-ring optical switch is difficult to obtain in the aspects of large free spectral range and low loss at the same time, and is a key technical support for constructing a high-integration wavelength selection optical switching chip.

The present disclosure provides a fiber bending loss test system and method based on spectral analysis, which relates to the field of fiber detection technology. This application uses multi-wavelength scanning to obtain power values ​​and interference signals, and transmits at least two measurement data in parallel within one transmission cycle; writes to the storage array according to the wavelength index and batch identifier, pauses and fills in points when insufficient alignment is detected; after filling in points, transmission is resumed and distributed loss information is calculated. In this way, data integrity, transmission throughput and real-time loss calculation accuracy are taken into account in a large-scale measurement environment, effectively avoiding the extension of measurement cycles and index confusion in conventional linear detection or fixed offset methods, and significantly improving the efficiency and reliability of fiber loss testing.

The invention discloses a double-nested hollow-core anti-resonance optical fiber with an off-center structure, and relates to the technical field of optical communication. The double-nested hollow-core anti-resonance optical fiber sequentially comprises an air core, a first-stage cladding tube, a second-stage cladding tube, a third-stage cladding tube and a peripheral cladding tube from inside to outside, the first-stage cladding tube and the peripheral cladding tube are fixed in an internally tangent manner, the second-stage cladding tube and the first-stage cladding tube are fixed in an internally tangent manner, and the third-stage cladding tube and the second-stage cladding tube are fixed in an internally tangent manner; the optical fiber is of an off-center structure which is vertically symmetrical and bilaterally asymmetrical. Compared with the conventional hollow-core anti-resonance optical fiber, the hollow-core anti-resonance optical fiber with specific structure parameters provided by the invention solves the problem that the conventional hollow-core anti-resonance optical fiber cannot well solve the problem of high bending loss under the condition of extremely short bending radius; the hollow-core optical fiber has relatively low confinement loss and bending loss, and has relatively great application potential in particle sensing and micro lasers.

The invention provides a non-inductive fatigue pressure monitoring cushion system and method based on multi-mode optical fiber sensing. Relates to the technical field of health monitoring and medical instruments, and comprises an optical fiber multi-mode sensing layer which is embedded in a cushion foaming elastomer, forms a two-dimensional sensing grid by staggered Bragg grating array optical fibers and micro-bend loss plastic optical fibers, and is used for collecting heart and lung micro vibration signals and body pressure distribution-micro body movement signals; and the optical signal conditioning and synchronous acquisition unit is coupled with an optical path of the optical fiber multi-mode sensing layer and is used for carrying out amplitude-phase demodulation and temperature drift compensation on optical fiber reflection / transmission light and digitally outputting multichannel original data. The non-inductive fatigue pressure monitoring cushion system and method based on multi-mode optical fiber sensing have the advantages of noninvasive comfort, high-precision recognition, self-adaptive intervention, low power consumption, long endurance and the like, and an accurate and continuous fatigue and pressure management solution is provided for sedentary people.

To provide an optical fiber cable that includes both a photonic bandgap fiber and an antiresonant fiber and has good bending characteristics, and a transmission method using the same. [Solution] An optical fiber cable includes a photonic bandgap fiber placed in a first state and an antiresonant fiber placed in a second state, wherein at least one of the macrobending loss of an optical fiber when placed in the first state is greater than the macrobending loss when placed in the second state, and the microbending loss of the optical fiber when placed in the first state is greater than the microbending loss when placed in the second state.

The invention relates to an optical fiber drawing method integrated with a coloring function and a production system, and relates to the technical field of optical fiber manufacturing, and the method comprises the following steps: melting and drawing an optical fiber preform to form a bare fiber; the bare fiber is cooled; coating the cooled bare fiber twice to form an inner coating and an outer coating; performing primary UV curing on the inner coating and the outer coating to enable the outer coating to reach a semi-cured state; coating coloring ink on the surface of the outer coating in a semi-cured state; performing secondary UV curing on the coloring ink, so that the coloring ink is cured, and the inner coating and the outer coating are finally cured; and the cured optical fiber is detected and taken up. The coloring procedure is integrated into the wire drawing process, integrated continuous production is achieved, and optical fiber microbend loss caused by multiple times of winding and unwinding is avoided; by means of molecular activity in a semi-cured state, coloring ink permeates to form an interpenetrating network structure, and adhesive force is improved.

An optical fiber including: (1) a first outer cladding region including a no-slope portion establishing a 0% baseline (Δ0); (2) a core region surrounded by the first outer cladding region, the core region including (i) an outer radius (r1) from 4.0 μm to 6.5 μm and (ii) a maximum relative refractive index (Δ1max) from 0.3% to 0.6%, the core region exhibiting an α value of 5 or greater; and (3) a depressed index cladding region surrounding the core region and surrounded by the first outer cladding region, the depressed index cladding region including (i) an outer radius (r3) from 14 μm to 28 μm, (ii) a relative refractive index (Δ3) from −0.45% to −0.30%, and (iii) a trench volume (VT) from 65%-μm2 to 140%-μm2. The optical fiber exhibits lower LP01 bending loss than LP11 bending loss at operating wavelengths in the O- and C-bands.

The utility model discloses a high-precision bending tool for optical fiber loss test, which comprises a test board, a connecting plate is arranged at the rear part of the surface of the test board, a first motor is fixedly arranged at the upper part of the back surface of the connecting plate, a bending mechanism is arranged at the upper part of the front surface of the connecting plate, and the bending mechanism comprises a connecting column. A swing arm is arranged on the front face of the connecting column, a limiting opening is formed in the front portion of the surface of the swing arm, a first air cylinder is fixedly installed on the inner wall of the limiting opening, a fixing block is fixedly connected to the end of the first air cylinder, and a traction mechanism is arranged on the lower portion of the surface of the connecting plate. According to the utility model, through the arrangement of the two groups of traction mechanisms, an optical fiber cable can be pulled and conveyed, and the cable is pulled and conveyed after the bending test of one point is completed, so that different positions of the optical fiber cable are tested through the bending mechanism, and the accuracy of the bending loss test is improved.

The present invention keeps bend loss at a low level in an optical waveguide in which a core includes a bend section. This optical waveguide (1) comprises: a core (11) that includes a bend section (11b); and a cladding (12) that surrounds the core (11) and has a lower refractive index than the core (11). The refractive index of the cladding (12) on the opposite side of the bend section (11b) from the curvature center (o) side of the bend section (11b) is lower than the refractive index of the cladding (12) on the curvature center (o) side of the bend section (11b).

The invention discloses a hollow-core and solid-core optical fiber hybrid optical fiber bundle and an optical cable comprising the same, and belongs to the technical field of optical fiber communication, the hollow-core and solid-core optical fiber hybrid optical fiber bundle comprises a hollow-core optical fiber, a solid-core optical fiber (the solid-core optical fiber can be G.652D, G.654E or G.655 and the like), a first layer of resin and a second layer of resin; a hollow-core optical fiber is arranged in the center of an optical fiber bundle to ensure that the bending radius of the hollow-core optical fiber is maximum when the optical fiber bundle is bent, the bending loss of the hollow-core optical fiber is reduced, and meanwhile, the periphery of the hollow-core optical fiber is coated with a layer of low-modulus resin to reduce the bending stress of the hollow-core optical fiber; meanwhile, the periphery of the low-modulus resin is filled with the high-modulus resin, so that the mechanical performance of the optical fiber bundle is guaranteed, the solid-core optical fibers arranged in the optical fiber bundle in a mixed mode are annularly distributed on the outer sides of the hollow-core optical fibers, the hollow-core optical fibers in the middle are protected through the solid-core optical fibers, and the overall mechanical strength of the optical fiber bundle is further improved.

This invention discloses a system and method for achieving single-mode transmission of sapphire optical fiber using a mechanically wound helical structure, belonging to the technical field of optical fiber transmission and high-temperature optical devices. The method involves winding sapphire optical fiber along a specific pitch to form a helical structure on a core, introducing controllable bending loss to suppress higher-order modes. Subsequently, high-temperature annealing and structural fixation ensure uniform stress distribution within the fiber and maintain a stable structure. Finally, optical testing verifies the single-mode transmission effect. This method offers advantages such as simple structure, no need for complex processing equipment, low cost, and high stability, and can be widely applied in high-temperature optical fiber sensing and high-power laser transmission.

The invention provides a thulium-doped optical fiber with high spectral purity and a preparation method thereof, and the thulium-doped optical fiber with high spectral purity adopts a profile design that the refractive index of a main gain layer follows linear gradual change distribution of a linear function and the refractive index of a secondary gain layer is constant, so that the mode distribution of an optical fiber fundamental mode is precisely overlapped with the main gain layer; the secondary gain layer is located at the lowest point of the waveguide refractive index; the design can effectively solve the problem that in the prior art, due to the limitation of the MCVD technology, the doping concentration difference of the main gain layer and the secondary gain layer is caused, and then the optimal emission wavelengths of different gain areas are inconsistent. Besides, depending on the bending loss difference of the main gain layer and the secondary gain layer, on the premise that the gain efficiency of the optical fiber is not sacrificed, effective separation of emission wavelengths of the main gain layer and the secondary gain layer can be achieved through bending regulation, the target wavelength of the main gain layer is reserved, and the non-target wavelength of the secondary gain layer is filtered out. And finally, the spectral purity of the thulium-doped optical fiber is improved.

The application relates to a three-component distributed optical fiber acoustic sensing device, system and detection method based on microstructure air hole sound wave sensitization, which comprises a distributed optical fiber acoustic sensing system and a sensing device, the device comprises at least one sensing unit, the sensing unit comprises an elastomer and a sensing optical fiber with air holes, and the sensing units are connected by connecting blocks; at least one sensing optical fiber is tightly attached to the elastomer to detect the deformation of the elastomer, and the cladding of the sensing optical fiber comprises air holes; the sensing device is connected with the distributed optical fiber acoustic sensing system. By adopting the microstructure air hole optical fiber as the sensing optical fiber, the equivalent Young's modulus and the effective refractive index of the sensing optical fiber are reduced, the bending loss is lower under the condition of ensuring that the optical fiber attenuation is lower, and the sound wave detection sensitization is realized.

The invention relates to a spiral winding type adjustable light attenuation device based on an optical fiber bending loss characteristic, and belongs to the technical field of light attenuation. The device comprises a winding shaft, a shaft disc, an inlet fixing bolt, a shaft fixing bolt, a fixing column and a magnetic attraction foot stand, and the device adjusts the attenuation size by controlling the bending winding length of an optical fiber, so that the intensity of an optical signal is controlled, the requirement for adjusting different light intensities by multiplexing a plurality of optical fibers can be met, and full-band attenuation adjustment is supported. Wherein the winding shaft is a cylinder with a uniform spiral track and a straight horizontal track and is used for winding optical fibers, and selection of the radius and the length of the winding shaft can be calculated according to a formula according to an actual loss demand range; the shaft discs are respectively arranged at two ends of the winding shaft and are used for protecting the optical fiber from being extruded and damaged and providing support for fixing the optical fiber; the inlet fixing bolts are used for ensuring that fibers at inlets at two ends of the fiber winding shaft are firm and reliable; the shaft fixing bolt is used for ensuring that the shaft fixing column compresses and compacts the optical fiber; the fixed column penetrates through the shaft disc and is embedded into the horizontal track of the winding shaft, so that the optical fiber wound on the optical fiber winding shaft is firm and reliable; the magnetic base is used for adsorbing and fixing the whole device on a cabinet or a tray. The optical attenuation device has the advantages of being small in size, low in cost, high in adjustment precision, good in stability, energy-saving, environment-friendly, capable of supporting multi-optical-fiber multiplexing adjustment and heat integration and the like, and can be widely applied to optical communication systems.

The present invention discloses a high birefringence anti-bending hollow core anti-resonant optical fiber applied to the green light band, belonging to the field of optical fiber technology. The present invention comprises: an outer cladding, an inner cladding and an air core region arranged in sequence from the outside to the inside; the outer cladding region is a hollow cylinder with a certain thickness; the inner cladding is a nested cladding tube structure, including a circular cladding tube and a first circular nested tube arranged inside it, an ice cream-shaped cladding tube composed of two sides of an equilateral triangle and a semicircular arc, and a second circular nested tube arranged inside it; the first nested cladding tube structure composed of the first circular nested tube and the circular cladding tube and the second nested cladding tube structure composed of the second circular nested tube and the ice cream-shaped cladding tube adopt different dielectric materials, different tube wall thicknesses and different deviation angles, thereby introducing high birefringence. The present invention can be applied to the green light band, has high birefringence and low bending loss, and has good polarization maintenance characteristics and anti-bending performance.

This optical fiber comprises a core, an inner cladding, a trench, and an outer cladding. When the relative refractive index difference of the core is ∆1, the relative refractive index difference of the inner cladding is ∆2, the relative refractive index difference of the trench is ∆3, the relative refractive index difference of the outer cladding is ∆4, the outer diameter of the core is 2r1, the outer diameter of the inner cladding is 2r2, the outer diameter of the trench is 2r3, and the outer diameter of the outer cladding is 2r4, the following relationships are established.　2.2 ≤ r2 / r1 ≤ 3.6; 3μm ≤ r3 － r2 ≤ 12μm; 0.25% ≤ ∆1 － ∆2 ≤ 0.50%; − 0.70% ≤ ∆3 ≤ − 0.10%; A zero-dispersion wavelength is 1296-1306 nm. A zero-dispersion slope is 0.088 ps / nm2 / km or less. A 500-meter cable cutoff wavelength is 1260 nm or less. A bending loss for light with a wavelength of 1310 nm when the optical fiber is wound around a mandrel having a diameter of 15 mm is 0.5 dB or less per turn.

The utility model discloses a tension-resistant tightly-wrapped aramid fiber optical fiber for ultra-long-distance flight of a small unmanned aerial vehicle in the related technical field of optical fibers, which comprises an optical fiber main body, two aramid fibers are symmetrically arranged on two sides of the optical fiber main body, tightly-wrapped layers are arranged on the outer sides of the optical fiber main body and the aramid fibers, and the optical fiber main body is a single-mode optical fiber which is not sensitive to bending loss. The optical fiber main body is a 6.657. A2 type optical fiber, and the outer side of the tight wrapping layer is provided with a super-hydrophobic layer. According to the utility model, the aramid fibers are arranged at the two sides of the optical fiber main body, the tight wrapping layer is extruded outside the optical fiber and the aramid fibers, and the three are combined together to form the tension-resistant tight wrapping aramid fiber optical fiber for the unmanned aerial vehicle, so that the mechanical performance of the optical fiber is improved while the good conductivity of the optical fiber is ensured, and meanwhile, the optical fiber in the application state is light in weight and convenient to manufacture. The ultra-long flight distance signal wired transmission of a small unmanned aerial vehicle can be easily realized, a common wireless electromagnetic wave control signal is prevented from being interfered, and the hydrophobic and oleophobic characteristics of the optical fiber are effectively improved due to the arrangement of the super-hydrophobic layer.

A method for measuring a bending loss of an optical fiber includes: determining a reference number of turns by which a wavelength dependency of a bending loss value of the optical fiber in a region of a predetermined transmission wavelength or less when the optical fiber is wrapped around a mandrel has an exponential function shape with respect to a transmission wavelength; measuring a first power of light for the optical fiber wrapped by the reference number of turns; and measuring a second power of light for the optical fiber wrapped by a number of turns larger than the reference number of turns. The method further includes obtaining, based on the first power of light and the second power of light, a bending loss value of the optical fiber at the predetermined transmission wavelength when the optical fiber is bent with the predetermined diameter.

This invention discloses a distributed optical fiber temperature measurement and calibration device, comprising a housing, a cover, an optical fiber body, and a temperature measurement and calibration module. The cover is hinged and rotated at the top of the housing, located at an opening. Inside the housing, a wireframe assembly for supporting and positioning the optical fiber body is fixedly installed. The temperature measurement and calibration module is fixedly mounted on the wireframe assembly. The wireframe assembly includes a wireframe body and an optical fiber slot. This invention effectively solves the problem of low calibration accuracy caused by the small coiling radius and high micro-bending loss of the optical fiber body in existing devices through the rational design of the wireframe assembly. The annular wireframe body increases the coiling radius of the optical fiber body, and the spacers, combined with the spacers, support the optical fiber body to form gaps, reducing bending stress and friction loss. Through holes and slots ensure airflow, further reducing micro-bending loss and improving signal transmission stability. The side heat dissipation assembly achieves forced heat dissipation through a cooling fan and an airflow guide shroud.

A detection system includes: at least one light source that outputs a plurality of test beams input to a proximal end portion side of an optical fiber and having different wavelengths and providing different bending losses of the optical fiber; at least one reflector that reflects each of the test beams propagating through the optical fiber, on a distal end portion side of the optical fiber; a plurality of light receiving units that receive a plurality of reflected beams each being a beam reflected by the at least one reflector, on the proximal end portion side; and a determination unit that, based on information about the reflected beams at the plurality of light receiving units, compares the information about the reflected beams with reference set values.

The invention belongs to the field of optical fiber sensing, and particularly relates to a three-layer step type optical fiber structure which has a wide bending radius sensing range and high bending sensitivity on the premise that bending loss can be resisted. By regulating and controlling the refractive index of the second layer of the fiber core, balance between low bending loss and high bending sensitivity is achieved. And meanwhile, two groups of spatially separated acoustic modes are excited under a specific refractive index condition, so that double Brillouin gain peaks can be formed. Specifically, when the refractive index of the second layer of the fiber core changes, the characteristics of optical and acoustic modes and opto-acoustic interaction are studied, and finally a W-type optical fiber structure with excellent performance is determined. The structure has a wider bending radius sensing range and higher bending sensitivity while keeping a good bending loss resistance characteristic. In a word, the optical fiber structure provided by the invention has important application value in the field of optical fiber double-physical parameter distributed sensing, and a new thought is provided for realizing high-performance Brillouin bending sensing.

The invention discloses a method for adaptively adjusting the coiling diameter of a gain optical fiber and a laser system, and relates to the field of optical fiber lasers, and the method comprises the steps: obtaining the temperature of the gain optical fiber under the current coiling diameter and the current LD current; determining the current transverse refractive index distribution of the gain fiber according to the temperature of the gain fiber based on a thermo-optic effect and a numerical modeling mode; according to the current transverse refractive index distribution, bending loss curves of conduction modes LP01 and LP11 in the gain fiber are calculated; according to a preset optimization principle, the optimal coiling diameter of the gain fiber is determined according to the bending loss curves of the conduction modes LP01 and LP11; the optimal coiling diameter is used as an adjustment basis of the coiling diameter of the gain fiber. The coiling diameter of the gain optical fiber is automatically adjusted according to self-adaptive feedback according to the temperature of the optical fiber, so that the TMI threshold value is increased.

This invention provides a transient displacement sensor based on uniform macro-bending loss of optical fiber and dynamic changes in tension and compression of an elastic substrate, along with its fabrication method and applications, belonging to the field of optical fiber sensor design. It includes an elastic substrate and an optical fiber inserted into the elastic substrate. The optical fiber is inserted into the elastic substrate at equal intervals and fixedly connected to the substrate at the insertion points. After insertion, the optical fiber exhibits a continuous wavy bend with identical shapes. One end of the optical fiber is connected to a light source, and the other end is connected to a photodiode. Deformation of the elastic substrate along the length of the optical fiber causes a change in the fiber's curvature. The width of the elastic substrate is 20-500 times the diameter of the optical fiber. The sensor fabrication method is simple, convenient, reliable, and easy to operate. The sensor measures a wider displacement range, can perform continuous measurements, and has a larger dynamic monitoring range. In application, this invention exhibits a large linear region and high reliability.

The fiber optic cable (1) of the present invention is characterized in that a plurality of F with geometric micro-bending loss characteristics are housed in the internal space (3S) of the sheath (3). μBL_G and optical microbending loss characteristics F μBL_Δβ The fiber (10), when the cable characteristics Dc of the fiber cable (1) are defined using the porosity a of the internal space (3S) and the number of cores b of the fiber (10) housed in the internal space (3S), has the microbending loss characteristic factor F expressed by the following formula. μBL_GΔβ The value is 1.2 × 10 －9 The following F μBL_GΔβ =F μBL_G ×F μBL_Δβ ×Dc.