| Entries |
| Document | Title | Date |
|---|
| 20080219617 | Plastic Optical Sensor - An optical fiber sensor comprising a housing having a cavity defined therein; at least two plastic optical fibers disposed such that cleaved ends of the respective fibers are located opposite each other within the cavity; a light source coupled to one of the fibers; and a detector coupled to the other fiber. | 09-11-2008 |
| 20080219618 | METHODS OF MAKING AND OPERATING A FIBER OPTIC SENSING DEVICE - In accordance with one exemplary embodiment the invention provides a multi-parameter fiber optic sensing system with an aperiodic sapphire fiber grating as sensing element for simultaneous temperature, strain, NO | 09-11-2008 |
| 20080226218 | Collision detection optical fiber sensor - An optical fiber | 09-18-2008 |
| 20080279499 | Device Including a System Adapted for Use in Temperature Compensation of Strain Measurements in Fibre-Reinforced Structures - The present invention relates to a device comprising a fibre-reinforced part and including at least one system comprising at least one optical fibre as well as connecting means adapted for connection of light emitting means and light receiving means to the optical fibre, said optical fibre comprising a number of reflecting structures. One object of the invention is to provide means suitable for use in providing compensation for temperature change in strain measurement, which may be built into fibre-reinforced parts of a device. This is obtained by having holding means adapted to hold one or more loops formed on the optical fibre, in a way where at least one loop may substantially freely change length when subject to a change in temperature. | 11-13-2008 |
| 20080285908 | Fiber optic transducer for simultaneous pressure and temperature measurement in fluid flow - The present invention relates a fiber optic transducer (FOT) and methods for measuring the pressure and temperature of a flowing fluid using such FOT, wherein such FOT contains a fiber optic having fiber Bragg gratings. The fiber Bragg gratings are measured during a flowing fluid to determine the difference in the change in wavelength exhibited by a reflected optical signal from the gratings. | 11-20-2008 |
| 20080285909 | OPTICAL FIBER SHAPE SENSING SYSTEMS - A medical instrument system includes an elongate flexible instrument body with an optical fiber substantially encapsulated in a wall of the instrument body, the optical fiber including one or more fiber gratings. A detector is operatively coupled to the optical fiber and configured to detect respective light signals reflected by the one or more fiber gratings. A controller is operatively coupled to the detector, and configured to determine a twist of at least a portion of the instrument body based on detected reflected light signals. The instrument may be a guide catheter and may be robotically or manually controlled. | 11-20-2008 |
| 20080310792 | Optical Fiber Sensor - An optical fiber sensor ( | 12-18-2008 |
| 20080317401 | Optic fiber bragg grating sensor - The optic fiber Bragg grating (FBG) sensor comprises of an elastic circular diaphragm and one or two FBG attached to the bottom surface of the elastic circular diaphragm. Two ends of the FBG are connected to an optic fiber for signal transmission. The FBG sensor readouts are independent of temperature fluctuation. The FBG sensor mechanism according to the present invention may be applied for various purposes such as a gauge pressure transducer, differential pressure transducer, load cell and displacement transducer with distributive capabilities. | 12-25-2008 |
| 20090003759 | Distributed Optical Pressure and Temperature Sensors - Disclosed herein is a carrier for an optical fiber having a plurality of optical sensors located thereon. Such carrier can be a thick-walled capillary tube or other shapes. The carrier has a sealed hollow body with a side wall. The side wall is profiled at least one predetermined location to form a thin-walled section and at least one optical sensor is attached to said thin-walled section. As the thin-walled section flexes in response to a pressure difference across it, the pressure difference is sensed by the optical sensor. The carrier may also have a slot defined on its side wall to receive the optical fiber. A temperature optical sensor may also be provided adjacent to the pressure optical sensor. | 01-01-2009 |
| 20090003760 | Distributed Optical Pressure and Temperature Sensors - Disclosed herein is a carrier for an optical fiber having a plurality of optical sensors located thereon. The carrier has a test section comprising a cavity and at least one geometric discontinuity, wherein in response to a pressure applied to the test section, a stress concentration is formed proximate to the geometric discontinuity, and wherein the optical sensor is adhered to at least a part of the geometric discontinuity. The cavity may be filled with a liquid or a gel. A temperature optical sensor may also be provided adjacent to the pressure optical sensor. | 01-01-2009 |
| 20090034903 | STRAIN SENSING DEVICE AND METHOD OF MEASURING STRAIN - A strain sensing device has a sub-assembly with at least one optical fiber therein, and a metallic coating encasing the sub-assembly. The metallic coating is strain coupled to the sub-assembly. A strain sensing system and a method of anticipating failure in a structure are provided. The strain sensing system and method of anticipating failure in a structure use the strain on the strain sensing device to calculate the strain on a structure of interest. | 02-05-2009 |
| 20090052832 | STRUCTURAL JOINT STRAIN MONITORING APPARATUS AND SYSTEM - Structural joint strain monitoring apparatus | 02-26-2009 |
| 20090060413 | Anti-intrusion device for fences or the like - An anti-intrusion device for fences or the like, comprising at least one, preferably two or more cables ( | 03-05-2009 |
| 20090080829 | Optical Strain Gauge Strips - The invention relates to an optical strain gage ( | 03-26-2009 |
| 20090092352 | OPTICAL FIBER STRAIN SENSOR - An optical fiber strain sensor, a method of fabricating the same, and a method of sensing strain. The method of strain sensing comprises providing an optical fiber having a fiber Bragg grating (FBG) formed therein; subjecting the optical fiber to a strain inducing force such that a grating period in a first portion of the FBG compresses and a grating period in a second portion of the FBG extends; and optically interrogating the FBG to determine a measure of a change in bandwidth of the FBG as a result of the compression and extension of the grating periods in the first and second portion respectively; whereby the measure of the change in the bandwidth is representative of the strain induced. | 04-09-2009 |
| 20090103853 | Interactive Surface Optical System - A device capable of obtaining information about objects both in contact with a surface and near to, but not in contact with, a surface of the device. The information may include position relative to the surface, pressure when in contact with the surface, shape of the object or objects, and many other properties. Certain embodiments make use of optical waveguides comprising a photoluminescent material which responds to first electromagnetic radiation of a first spectrum propagated through the system by emitting second electromagnetic radiation of a second spectrum. The distribution of the first electromagnetic radiation is altered by pressure on the surface or by the presence of objects near the surface of the device. The distribution of the second electromagnetic radiation is measured using photosensors and processed to determine desired information. | 04-23-2009 |
| 20090123110 | Surface Temperature Sensing System - A sensor apparatus for sensing parameters of an object may include at least one optical fiber, one or more attaching members and a tensioner. The one or more attaching members may be coupled to the optical fiber and may attach the one optical fiber to an object. The tensioner may be coupled to the optical fiber and may secure the one or more optical fiber against a surface of an object. | 05-14-2009 |
| 20090123111 | OPTICAL FIBER GRATING SENSORS AND METHODS OF MANUFACTURE - Systems and methods comprise or involve optical fibers having Bragg gratings. The optical fibers can be assembled in a parallel manner into a fiber sensor configuration. Bragg gratings can be written onto different cores of optical fibers. Bragg gratings may be written at a same or nearly same axial position for all optical fibers in the configuration and may be written at the same time and may have a substantially equal index of refraction variation and unequal lengths. Spaced Bragg gratings may also have characteristic sidelobe spectrums for tagging the respective gratings. Gratings can also be written at different wavelengths and over another grating at the same location. | 05-14-2009 |
| 20090123112 | FIBER OPTIC MICROPHONE AND A COMMUNICATION SYSTEM UTILIZING SAME - An arrangement for a fiber optic microphone having at least one pair of optical fibers, each having an input end portion and an output end portion made of a material having a critical refractive angle θ | 05-14-2009 |
| 20090129722 | Fiber Bragg Grating Sensor - An optical fiber strain sensor, a method of fabricating the same, and a method of sensing strain ( | 05-21-2009 |
| 20090180730 | Opto-acoustic pressure sensor | 07-16-2009 |
| 20090180731 | PHOTONIC COUPLER - A photonic coupler including a substrate, first and second waveguides disposed along a longitudinal direction of the substrate for propagation of respective first and second optical signals along the longitudinal direction, and a coupling region between the first and second waveguides and including a medium of a refractive index different from the first and second waveguides. The coupling region has a width extending from the first waveguide to the second waveguide and a breadth extending laterally to form an angle to the longitudinal direction for frustrated total internal reflection of the first optical signal at an interface between the coupling region and the first waveguide. | 07-16-2009 |
| 20090185772 | Fiberoptic patient health multi-parameter monitoring devices and system - A patient monitoring system includes a plurality of diffraction gratings integrated along the length of an optical fiber, wherein the optical fiber and each grating are together configured to alter either the effective refractive index or grating periodicity of the respective grating at its corresponding location along the fiber in response to at least one desired external stimulus. | 07-23-2009 |
| 20090185773 | Apparatus and Method for Measuring Convergence Using Fiber Bragg Grating Sensor - Disclosed is an apparatus for measuring convergence using a fiber Bragg grating sensor measuring slight deformation, capable of measuring the convergence such as the inclination or the gravitational acceleration of a measurement target including a bridge or a tunnel by measuring the deformation of the fiber Bragg grating sensor when the measurement target is inclined or vibrated, as well as a measurement method using the apparatus. The apparatus includes a main body that is installed on a measurement target; a fixture that is fixedly installed at the front of the main body; a rotator that is horizontally installed apart from the fixture at a predetermined distance and is rotatably installed in the main body using a bearing; an optical fiber that is adhered to upper outer surfaces of the fixture and the rotator so as to maintain a horizontally tensioned state and has optical terminals installed on opposite ends thereof; a fiber Bragg grating sensor that is installed on the optical fiber between the fixture and the rotator; and a bob that is vertically connected with a lower portion of the rotator by a support having a predetermined length. The apparatus is installed on the measurement target after setting a reference value and then calculates a quantity of displacement caused by variation of the ground, so that values of angular displacement and gravitational acceleration displacement are measured. | 07-23-2009 |
| 20090202195 | Fiber Optic Pressure Sensors and Catheters - A catheter with many fiber optic pressure sensors. The sensor diaphragm is formed from a wafer with a thin silicon layer and a silicon substrate layer separated by a silicon dioxide layer. A method includes masking and etching channels through the silicon substrate layer in a pattern of concentric circles to form a concentric circular etched channels and cylindrical unetched portions of the silicon substrate layer between the channels, exposing the silicon dioxide in the etched regions, and dissolving the exposed silicon dioxide to expose the crystalline silicon layer in the etched regions. The unetched cylindrical portion of the silicon substrate forms the diaphragm support element and the thin silicon layer forms the diaphragm. After applying a reflective coating to the exposed thin silicon layer, the support element face is adhered to the end face of a tubular housing, and a fiber optic probe is inserted in the tubular housing. | 08-13-2009 |
| 20090220190 | Leak Detector Using an Optical Fibre - A leak detection apparatus comprising an optical fibre sensor ( | 09-03-2009 |
| 20090252450 | Regression and Erosion Measurement System and Method - A method and system for determining the length of collocated waveguides in a high erosion environment, such as a solid rocket motor or a braking system. The system provides for mating optical waveguides having different attenuation coefficients within the combusting, eroding, or otherwise regressing material. Optical energy generated by the environment (e.g., from burning fuel), or which is introduced and scattered into the environment, travels through the waveguides to detector means coupled thereto. The intensities of the arriving optical energy are compared and the length of the collocated waveguides calculated therefrom. By calculating the length of the waveguides over time, a regression rate is determined. | 10-08-2009 |
| 20090252451 | Intensity Modulated Fiber Optic Strain Sensor - A strain sensor includes an optical fiber with at least one optical fiber, a reflector body with a reflective surface, a housing affixed to the optical fiber probe and to the reflector body. The reflective surface is spaced apart at a distance d from the ends of the probe's fibers and receives light from the end of the fiber and to reflect at least a portion of the light into the end of the fiber. The housing is attached to the fiber probe at a first end of the housing and attached to the reflector body at a second end of the housing. The housing is affixed to the material to be measured, and in the material causes a change in gap between the fiber end and the reflective surface, modulating the amount of light received in the receiving fiber, detectable by a photodetector connected to the receiving fiber. | 10-08-2009 |
| 20090263072 | Tilted Grating Sensor - The present invention relates to a sensor using a tilted fiber grating to detect physical manifestations occurring in a medium. Such physical manifestations induce measurable changes in the optical property of the tilted fiber grating. The sensor comprises a sensing surface which is to be exposed to the medium, an optical pathway and a tilted grating in the optical pathway. The grating is responsive to electromagnetic radiation propagating in the optical pathway to generate a response conveying information on the physical manifestation. | 10-22-2009 |
| 20090279826 | DOOR HANDLE APPARATUS FOR VEHICLE - A door handle apparatus for a vehicle, opening and closing a vehicle door, the door handle apparatus includes an informing portion for visually informing a state of the vehicle door, including a locking/unlocking state thereof, to a user by a decorative light, which is a visible light, an operation detecting portion for optically detecting an active-direct operation to the door handle apparatus by the user based on changes in an detection light, and an optical waveguide for transmitting the decorative light and the detection light, which is inputted from a first end portion of the optical waveguide, to a second end portion of the optical waveguide, the optical waveguide functioning as the informing portion by leaking the decorative light on a transmission path so as to be outwardly emitted and as the operation detecting portion by outputting the detection light from the second end portion of the optical waveguide. | 11-12-2009 |
| 20090285521 | OPTICAL FIBER SENSOR - An optical fiber sensor which functions as a tactile sensor includes a plurality of shearing stress sensor sections including respective optical fibers and a plurality of gratings for reflecting light beams having predetermined wavelengths. The gratings are disposed in the optical fibers and arrayed along a plane parallel to the direction in which a shearing stress is applied from an object to the shearing stress sensor sections. The sensor also includes a perpendicular stress sensor section including an optical fiber and a plurality of gratings for reflecting a light beam having a predetermined wavelength. The gratings are disposed in the optical fiber and arrayed along a plane parallel to the direction in which a perpendicular stress is applied from the object to the perpendicular stress sensor section. Preferably, stress direction converting means such as elastic members for converting the direction of an applied stress are mounted on the optical fibers. | 11-19-2009 |
| 20090324160 | FIXTURE FOR SHAPE-SENSING OPTICAL FIBER IN A KINEMATIC CHAIN - Localized strain is effectively eliminated in a shape sensing optical fiber where the fiber exits a link in a kinematic chain. In one aspect, the fiber is positioned in a channel within a fiber fixture portion of the link, and a surface of a lip of the channel is curved. The curved surface of the lip begins tangent to a wall of the channel and has a maximum radius of curvature that is less than the minimum bend radius that the fiber will experience during shape sensing. In another aspect the fiber is positioned within a shape memory alloy tube that extends from the link. | 12-31-2009 |
| 20090324161 | FIBER OPTIC SHAPE SENSOR - A shape sensing system to determine the position and orientation of one link with respect to another link in a kinematic chain. An optical fiber is coupled to two or more links in a kinematic chain. A shape sensing segment is defined to start at a proximal link and to end at a distal link, crossing one or more joints. A reference frame is defined at the start of the shape sensing segment. As the joints move, an interrogator senses strain in the shape sensing segment. The sensed strain is used to output a Cartesian position and orientation of the end of the shape sensing segment with respect to the reference frame defined at the start of the shape sensing segment. The pose of the kinematic chain is determined from the Cartesian positions and orientations of one or more shape sensing segments defined for the kinematic chain and from an a priori model and constraints of the kinematic chain. | 12-31-2009 |
| 20100002982 | Arrangement for monitoring a stressed body and method for the production thereof - A system serves to monitor a body exposed to high mechanical or thermal stress. The body has a surface that has at least one groove with two groove lateral walls which are oppositely disposed and adjacent to the surface. An optical waveguide devoid of protective coating, which has a light-guiding core and a casing surrounding it and in which at least one sensor is provided for the optical detection of a measurement variable, is embedded in the groove. The optical waveguide is fixed in place in an area of one of the groove lateral walls, which is adjacent to the surface, by means of at least one caulking. | 01-07-2010 |
| 20100002983 | DISTRIBUTED OPTICAL FIBER DETECTION SYSTEM - A distributed elongated optical fiber detection system is provided, having at least one sensitive region, and being capable of detecting the occurrence and location(s) of one or more events along its length that cause one or more perturbations in the at least one sensitive region. In one embodiment of the invention, the novel detection system includes, at its first end, an optical signal source capable of launching a signal in a first signal mode through an optical fiber waveguide comprising at least one sensitive region along its length, and configured for transmitting at least two signal modes therethrough, toward its second end. A reflecting device, capable of reflecting only signals in a second signal mode, is positioned at the second end of the waveguide. An occurrence of at least one event in at least one sensitive region causes a perturbation in the waveguide sufficient to couple at least a portion of the energy of the forward traveling signal into a second signal mode, such that the signal in the second signal mode is reflected back toward the first end of the waveguide. A detector, capable of detecting at least one characteristic of a reflected signal in the second signal mode, is connected to the first end of the waveguide, such that when the at least one event occurs, and a reflected signal in the second signal mode is produced, the detector is capable of determining the quantity of one or more occurring events as well as a location of each of the events along the waveguide lengths. In another inventive embodiment, instead of a reflector, the detector is connected to the second end and detects the signal in the second mode directly. | 01-07-2010 |
| 20100008619 | Optical fiber-mounted porous photonic crystals and sensors - An embodiment of the invention is a remote sensor that has an optical fiber terminating in a tip. A thin film porous particle having a characteristic optical response that changes in the presence of an analyte is optically coupled and physically attached to the tip of the optical fiber. The optical response of the particle changes in the presence of analyte, and the particle also serves to concentrate analyte. The thin film porous particle can be functionalized toward sensitivity for a predetermined analyte or analytes. A method of remote sensing exposes the remote sensor to an environment to be monitored for analyte. The thin film porous particle is probed with a beam of light. Reflected light is monitored through the optical fiber for a shift in frequency or intensity. | 01-14-2010 |
| 20100021106 | TEMPERATURE-COMPENSATED FIBRE OPTIC STRAIN GAUGE - A temperature-compensated fibre optic strain gauge ( | 01-28-2010 |
| 20100067845 | INCLINOMETER SYSTEM - Disclosed is an inclinometer system capable of detecting the inclination of the ground using a fiber bragg grating sensor to precisely measure the deformation of the ground. The inclinometer system includes at least one measuring unit, and the measuring unit includes a body provided therein with a receiving part, a frame inserted into the body, a weight member inserted in to the frame and having one end hinged to the frame, the weight member rotating in cooperation to inclination of the body, an optical fiber | 03-18-2010 |
| 20100074572 | FIBER OPTIC SENSING DEVICE AND METHOD - A device includes a stationary, rotary component, and a fiber optic sensing system. The fiber optic sensing system includes a cable having one or more fiber optic sensors disposed on the stationary component, the rotary component, or combinations thereof. The fiber optic sensing system is configured to detect one or more first parameters including temperature, strain, pressure, vibration, torque; or combinations thereof related to the stationary component, the rotary component, or combinations thereof. The one or more first parameters is used to determine one or more second parameters including thermal expansion, clearance, fluid flow rate variation, condensation, fluid leakage, thermal loss, life, thermal stress, or combinations thereof related to the stationary component, the rotary component, or combinations thereof. | 03-25-2010 |
| 20100150497 | EVANESCENT SENSOR USING A HOLLOW-CORE RING MODE WAVEGUIDE - Method and apparatus enable optical evanescent sensing utilizing a waveguide with an annular core. The annular core can provide detectable sensitivity to a measurand due to optical interactions with contents along an inside surface of the annular core since optical properties of the contents vary with changes in the measurand. | 06-17-2010 |
| 20100158433 | METHOD AND APPARATUS FOR MEASURING FIBER TWIST BY POLARIZATION TRACKING - An apparatus and accompanying method to measure fiber twist. The method includes independent determination of fiber bending by measuring strain sensing in outer cores of the same fiber. The apparatus includes a multi-core optical fiber comprising a center core and a plurality of peripheral cores at a distance radially from the center core and running parallel to the center core. The center core includes at least one fiber Bragg grating with polarization-dependent reflectivity. The fiber Bragg grating reflects the launched light as reflected light. The apparatus includes a multi-core optical fiber bend sensing system operable to communicate with the multi-core optical fiber. The multi-core optical fiber bend sensing system is operable to sense a bend in the multi-core optical fiber. The apparatus includes a processor operable to communicate with the polarization controller. The apparatus includes a polarization vector analyzer operable to communicate electronically with the processor, and optically with a portion of the light launched into the central core of the optical fiber. The polarization vector analyzer is operable to measure the state of polarization of the launched light. The polarization controller is operable to align the polarization of the launched light with the minor axis or the major axis of birefringence of the FBG. The processor is operable, after the polarization controller aligns the polarization of the launched light, to determine a twist in the multi-core optical fiber based on the polarization of the launched light and the bend in the multi-core optical fiber. | 06-24-2010 |
| 20100158434 | METHOD AND DEVICE FOR DYNAMIC MEASUREMENT OF THE RADIAL DEFORMATION OF A ROLLING BEARING RING - A method and a device for dynamic measurement of the radial deformation of a bearing ring ( | 06-24-2010 |
| 20100158435 | SIDE-HOLE CANE WAVEGUIDE SENSOR - A side-hole optical cane for measuring pressure and/or temperature is disclosed. The side-hole cane has a light guiding core containing a sensor and a cladding containing symmetrical side-holes extending substantially parallel to the core. The side-holes cause an asymmetric stress across the core of the sensor creating a birefringent sensor. The sensor, preferably a Bragg grating, reflects a first and second wavelength each associated with orthogonal polarization vectors, wherein the degree of separation between the two is proportional to the pressure exerted on the core. The side-hole cane structure self-compensates and is insensitive to temperature variations when used as a pressure sensor, because temperature induces an equal shift in both the first and second wavelengths. Furthermore, the magnitude of these shifts can be monitored to deduce temperature, hence providing the side-hole cane additional temperature sensing capability that is unaffected by pressure. Additionally, the side-hole cane can be used to measure a differential pressure between a first pressure ported to the side-holes and a second external pressure. | 06-24-2010 |
| 20100195950 | Optical Sensor Fiber Having Zone Which is Sensitive to Bending, Sensor Having Such Sensor Fiber, and Method for Producing - An untreated fiber section in an optical sensor fiber has a zone which is framed by surface-treated fiber sections, thus making it possible to determine, by metrology, a mixture of light modes in the untreated fiber section that depends on bending. This advantageously makes it possible to measure the bending in the optical sensor fiber in a very accurate manner. The optical sensor fiber may be used in sensor having a laser diode and a photodiode. | 08-05-2010 |
| 20100202727 | FIBER OPTIC SHAPE SENSOR - A shape sensing system to determine the position and orientation of one link with respect to another link in a kinematic chain. An optical fiber is coupled to two or more links in a kinematic chain. A shape sensing segment is defined to start at a proximal link and to end at a distal link, crossing one or more joints. A reference frame is defined at the start of the shape sensing segment. As the joints move, an interrogator senses strain in the shape sensing segment. The sensed strain is used to output a Cartesian position and orientation of the end of the shape sensing segment with respect to the reference frame defined at the start of the shape sensing segment. The pose of the kinematic chain is determined from the Cartesian positions and orientations of one or more shape sensing segments defined for the kinematic chain and from an a priori model and constraints of the kinematic chain. | 08-12-2010 |
| 20100215311 | Method and Apparatus for Shape and End Position Determination Using an Optical Fiber - A method of determining the shape of an unbound optical fiber includes collecting strain data along a length of the fiber, calculating curvature and bending direction data of the fiber using the strain data, curve-fitting the curvature and bending direction data to derive curvature and bending direction functions, calculating a torsion function using the bending direction function, and determining the 3D shape from the curvature, bending direction, and torsion functions. An apparatus for determining the 3D shape of the fiber includes a fiber optic cable unbound with respect to a protective sleeve, strain sensors positioned along the cable, and a controller in communication with the sensors. The controller has an algorithm for determining a 3D shape and end position of the fiber by calculating a set of curvature and bending direction data, deriving curvature, bending, and torsion functions, and solving Frenet-Serret equations using these functions. | 08-26-2010 |
| 20100232739 | Method for producing a bending sensor - At least one sensing region is formed on the bending sensor by providing a flexurally elastic base cover which is interrupted in at least one partial region of the sensing region or is structured using elevations and/or depressions. At least one planar optical fiber core is generated on the base cover. The optical fiber core has a greater index of refraction than the base cover. The optical fiber core is covered by a shroud. The optical fiber core has a greater index of refraction than the shroud. | 09-16-2010 |
| 20100232740 | POF STRAIN SENSOR USING PHASE MEASUREMENT TECHNIQUES - An optical fiber sensor has a measurement path and a reference path. Both paths each consist of two optical fibers and are fed with modulated light. The fibers of the reference path have a predefined difference in length, whereas the fibers of the measurement path are the same length. All fibers are at approximately the same temperature. An evaluation circuit determines the phase differences in each case between the fibers of the measurement path and of the reference path. A measurement value calculated from the phase differences is then output. | 09-16-2010 |
| 20100254650 | HIGH SPATIAL RESOLUTION DISTRIBUTED TEMPERATURE SENSING SYSTEM - A system and a method that are useful for making temperature measurements that are distributed over a distance. In one aspect, the system comprises a plurality of Bragg grating measurement points disposed in an optical fiber with a predetermined spacing between adjacent Bragg grating measurement points. The system also comprises a substrate with the optical fiber disposed thereon, the optical fiber wrapped around the substrate with at least one predetermined wrap angle. The predetermined wrap angle and the predetermined spacing may be selected to allow a temperature measurement signal to be distinguished from a bending measurement signal. The substrate may have a first coefficient of thermal expansion greater than a second coefficient of thermal expansion of the optical fiber and may comprise alternating sections of hollow tube and solid rod. | 10-07-2010 |
| 20100272384 | FORCE-MOMENT SENSOR - A force-moment sensor is provided for measuring at least one force and/or moment, which comprises a first part, a second part and an optical fibre arranged therebetween, said optical fibre comprising in at least one section a component for detecting deformations and/or stresses of the fibre transversely to its longitudinal axis. The present invention further relates to a method for measuring forces and/or moments. Thus, a fibre is provided which comprises at least one component for detecting deformations and/or stresses of the fibre transversely to a longitudinal axis of the fibre and into which light is introduced. According to this method, a force and/or moment acts on the fibre, wherein at least one component of the force and/or moment acts perpendicularly to the longitudinal axis of the fibre. The light reflected in the fibre is then detected and the detected spectrum analysed. | 10-28-2010 |
| 20100278476 | COMPONENT MONITORING ARRANGEMENT - Fibre substrates act as a conduit for light along which response signals are transmitted to a controller in the form of an electronic device associated with a component. The processed signals are stored in a local memory to provide a component history and a prediction of future performance and life. Service and repair history may be added to the component device memory to enable a complete history to be stored with the component. A controller may transmit data to an external controller or display through typically a wireless connection. Power to the component electronics may be provided by an induction loop or transformer. | 11-04-2010 |
| 20100284646 | FIBER OPTIC GRATING MEASURING DEVICE - A fiber optic grating measuring device includes a wide-band light source, an optical coupler coupled to the wide-band light source, and an output unit. A long-period fiber grating includes a first end coupled to the optical coupler and a second end coupled to the output unit. A first fiber Bragg grating is coupled to the optical coupler. The first fiber Bragg grating serves as a measuring terminal and is adapted to be mounted on an object having a physical quantity, such as a strain or temperature, to be measured by the fiber optic grating measuring device. A second fiber Bragg grating is coupled to the optical coupler. The second fiber Bragg grating serves as a free terminal and is located adjacent to the first fiber Bragg grating. The second fiber Bragg grating compensates an error resulting from a temperature change to increase the measuring accuracy. | 11-11-2010 |
| 20100296771 | Evanescent Field Optical Fiber Devices - The present invention is directed to an evanescent field optical fiber device including one or more optical fibers and a support which assures mechanical strength of the optical fiber wherein one or more grooves has been machined in the support and in the coating of the one or more optical fiber in order to gain access to the evanescent field. The invention is also directed to the use of a support in the mechanical and chemical removal of coating from an optical fiber and a method of gaining access to the evanescent field of an optical fiber device. | 11-25-2010 |
| 20100296772 | APPARATUS FOR SENSING A MOTION - The present disclosure provides an apparatus for sensing a motion. The apparatus comprises an optical fibre portion comprising a Bragg grating and an element for reducing an impact of an external force that is transversal to the Bragg grating. Further, the apparatus comprises a contact region arranged so that movement of a further region, that is in direct or indirect contact with the contact region and moves in a direction along a portion of the apparatus, causes movement of the optical fibre portion at the contact region. The apparatus also comprises a holder arranged for reducing movement of the optical fibre portion at a holding region when the optical fibre portion is moved at the contact surface. The apparatus is arranged so that movement of the contact region relative to the holding region causes a change in strain of the Bragg grating. | 11-25-2010 |
| 20100303403 | ON-LINE FIBER BRAGG GRATING DITHERING - An apparatus for determining a property, the apparatus including: an optical fiber having a series of fiber Bragg gratings, each fiber Bragg grating in the series being characterized by a light reflection frequency at which the fiber Bragg grating reflects light; wherein: the light reflection frequency for each fiber Bragg grating is different from the light reflection frequency of each adjacent fiber Bragg grating to minimize resonance of light between at least two of the fiber Bragg gratings in the series; at least two fiber Bragg gratings in the series have light reflection frequencies that overlap; and a change in the light reflection frequency of each fiber Bragg grating in the series is related to the property at the location of the each fiber Bragg grating. | 12-02-2010 |
| 20100303404 | TRANSDUCER WITH MULTIMODAL OPTICAL FIBRE AND MODE COUPLING AND METHOD FOR MAKING SAME - An optical fibre transducer is sensitive to at least one parameter of an environment in which it is located, the modification of the parameter(s) resulting in a modification of at least one measurable characteristic of a light wave injected into the optical fibre and flowing through the transducer, the optical fibre being multimodal and including an element adapted so that the modification of the light wave characteristic is based on a modification of mode coupling resulting from the modification of the environment parameter, the element leading to a mode coupling modification that generates, during the modification, a deformation of the optical fibre in the transducer according to a predetermined pattern. The element leading to the mode coupling modification is a hollow tube containing a relief pattern and surrounding the optical fibre at the transducer in a straight part of the fibre. | 12-02-2010 |
| 20100310207 | OPTICAL MICROMACHINED PRESSURE SENSOR - It is an objective of the present invention to provide a highly sensitive optical pressure sensor that uses a Mach-Zehnder Interferometer to measure pressure. The pressure sensor comprises a deflectable diaphragm including a substantially central boss and channel and an optical waveguide having a first arm and a second arm, wherein the first arm is substantially aligned with an edge of the boss and the second arm is substantially aligned with an edge of the channel, and further wherein the first and second arms contain a periodic array of etched holes to improve the overall sensitivity of the pressure sensor. The pressure sensor further comprises a light source coupled to the optical waveguide for introducing light to the waveguide and a light detector coupled to the waveguide for detecting changes in the intensity of light. The change in light intensity is then correlated to an applied pressure. | 12-09-2010 |
| 20100329602 | SMART FASTENER AND SMART INSERT FOR A FASTENER USING FIBER BRAGG GRATINGS TO MEASURE STRAIN AND TEMPERATURE - A measurement device including a fastener for use in attaching a first member to a second member, in which the fastener has an aperture extending through a length of the fastener, and a first optical fiber located within the aperture, in which the first optical fiber includes at least one fiber Bragg grating sensor. At least a portion of the first optical fiber can be secured within the aperture. A first end of the first optical fiber can be connected to an associated first optical connector and a second end of the first optical fiber can be connected to an associated second optical connector. | 12-30-2010 |
| 20110007996 | Optical Fiber Pipeline Monitoring System and Method Field - In accordance with one aspect of the present invention, a fiber surveillance system for monitoring a pipeline is provided. The surveillance system includes an optical fiber acoustically coupled to the pipeline to detect acoustic signals associated with vibrations or other activity near or from the pipeline. Optical energy is injected into the optical fiber and an optical detector receives an optical return-signal having certain characteristics resulting from vibrations impinging on the optical fiber. An analyzer is configured to determine operating information about the pipeline based on the optical return-signal. Two or more fibers can be acoustically coupled to the pipeline and arranged in varying configurations to yield greater resolution. | 01-13-2011 |
| 20110007997 | FIBER-OPTIC TEMPERATURE SENSOR ASSEMBLY - A fiber-optic temperature sensor assembly comprises a cap with an inner cavity. A sensor member is received in the inner cavity of the cap. The sensor member has light-transmitting properties adapted to change with temperature variations. An optical fiber has a first end received in the inner cavity of the cap, and a second end of the optical fiber being adapted to be connected to a processing unit for transmitting light signals between the sensor member and the processing unit. A pressing device is received in the cap and pressing against the sensor member such that the sensor member is in operational contact with the first end of the optical fiber for transmission of light therebetween during operation of the fiber-optic temperature sensor assembly. | 01-13-2011 |
| 20110044577 | FIBER-OPTIC EXTENSOMETER - An extensometer having a loop of a single-mode optical fiber. At least two points of the loop are attached to desired locations on a specimen. Light is transmitted through the loop and the transmitted optical power is measured by a photodetector. The deformation of the specimen causes the size and shape of the loop to change, which changes the transmitted optical power. The change in optical power is related to extension or compression using calibration curves. The sensor works on the principle of transmitted power modulation through the curved section. | 02-24-2011 |
| 20110044578 | Fixture for Shape-Sensing Optical Fiber in a Kinematic Chain - Localized strain is effectively eliminated in a shape sensing optical fiber where the fiber exits a link in a kinematic chain. In one aspect, the fiber is positioned in a channel within a fiber fixture portion of the link, and a surface of a lip of the channel is curved. The curved surface of the lip begins tangent to a wall of the channel and has a maximum radius of curvature that is less than the minimum bend radius that the fiber will experience during shape sensing. In another aspect, the fiber is positioned within a shape memory alloy tube that extends from the link. | 02-24-2011 |
| 20110058768 | COMPACT FIBER OPTIC SENSORS AND METHOD OF MAKING SAME - A compact, optically double-ended sensor probe with at least one 180° bend provided in the optical fiber in close proximity to a fiber Bragg grating temperature sensor suspends the optical fiber within a casing in such a way that the expansion and contract of the probe casing will not materially influence the temperature reading of the fiber Bragg grating by adding time varying or temperature varying stress components. | 03-10-2011 |
| 20110075964 | Optical Fiber Structure Monitoring and Analysis - A system and method for monitoring the structural integrity of a structure is provided. An optical fiber is acoustically coupled to one or more of the structural elements. A source of optical energy is configured to inject optical energy into the optical fiber, and an optical detector is configured to detect a first optical return signal having characteristics that are affected by vibrations of the structural elements. An analyzer measures characteristics of the optical return signal to determine information concerning the movement of the structural elements monitored by the fiber optic cable. The results of the analyzer can be stored and so that the analysis of the optical return signal can be compared to previously recorded signals to determine changes in structural integrity over time. Multiple fibers can be acoustically coupled to the monitored structural elements to obtain additional data concerning the structural integrity. | 03-31-2011 |
| 20110110620 | ROTATED SINGLE OR MULTICORE OPTICAL FIBER - An apparatus for estimating a shape, the apparatus including: an optical fiber configured to conform to the shape and having a first core offset from a centerline of the optical fiber, the first core having an optical characteristic configured to change due to a change in shape of the optical fiber wherein a change in the optical characteristic is used to estimate the shape. A method for estimating a shape is also disclosed. | 05-12-2011 |
| 20110110621 | NOVEL SENSOR ARRAY CONFIGURATION FOR EXTENDING USEFUL SENSING LENGTH OF A SWEPT-WAVELENGTH INTERFEROMETRY BASED SYSTEM - An apparatus for estimating a parameter at distributed locations, the apparatus including: an optical fiber having: a first series of fiber Bragg gratings (FBGs) and configured to measure the parameter at a portion of the distributed locations; a second series of FBGs and configured to measure the parameter at another portion of the distributed locations; and an optical interrogator configured to illuminate the optical fiber and to receive light signals resulting from the illumination, the light signals including first light signals from the first series of FBGs within a first range of wavelengths, second light signals from the second series of FBGs within a second range of wavelengths, and other light signals within a third range of wavelengths, the ranges of wavelengths being distinct from each other; wherein the first light signals and the second light signals are used to estimate the parameter at the distributed locations. | 05-12-2011 |
| 20110194806 | TILT METER INCLUDING OPTICAL FIBER SECTIONS - A tilt meter includes a housing structure defining an inner chamber sealed from an environment outside the housing structure. First and second optical fiber sections are provided in the inner chamber. The second optical fiber section is optically coupled to the first optical fiber section, with the second optical fiber section rotated azimuthally with respect to the first optical fiber section. The first and second optical fiber sections are arranged to receive light transmitted from a remote light source, and a tilt of the housing structure induces a differential pressure within the inner chamber to be detected by the first and second optical fiber sections. | 08-11-2011 |
| 20110194807 | OPTICAL SENSOR - An optical sensor for detecting a substance includes a first waveguide and a second waveguide optically coupled via a directional coupler to the first waveguide. The sensor has a functional surface in a region of the directional coupler for accumulating or storing the substance to be detected so that an intensity of a coupling arranged by the directional coupler between the first waveguide and the second waveguide can be changed by the accumulating or storing of this substance. The first waveguide extends in a freely floating manner over a coupling path covered by the directional coupler or rests on a swellable material. The first waveguide is guided in a vicinity of the coupling path so that a spacing between the first waveguide and the second waveguide can be changed there by a deformation or movement of the first waveguide or of a carrier of the first waveguide. | 08-11-2011 |
| 20110229071 | PRESSURE SENSOR ARRANGEMENT USING AN OPTICAL FIBER AND METHODOLOGIES FOR PERFORMING AN ANALYSIS OF A SUBTERRANEAN FORMATION - A sensor arrangement using an optical fiber and methodologies for performing an analysis of a subterranean formation, such as a subterranean formation containing a hydrocarbon based fluid. The sensor arrangement may be used to measure one or more physical parameters, such as temperature and/or pressure, at a multiplicity of locations in the subterranean reservoir. The sensor arrangement may comprise a sensor array comprising an elongated outer casing for insertion in the subterranean formation and into a fluid in the subterranean formation. The sensor array may comprise an optical fiber defining an optical path that links one or more temperature sensors and one or more pressure sensors and transports measurement data generated by the temperature and pressure sensors. A data processing system may be connected to the sensor array to receive measurements from the sensor array and to compute one or more values of a property of an extraction installation operating on the subterranean formation. | 09-22-2011 |
| 20110249934 | INTRUDER DETECTION SYSTEM - An intruder detection system including a light emitting unit, a light guide, and a light receiving unit. The light emitting unit is arranged to emit light into the light guide and the light guide is arranged to guide the light to the light receiving unit. The impact of an intruder on the light guide causes changes in the characteristics of the light received at the light receiving unit. | 10-13-2011 |
| 20110274387 | APPARATUS FOR SENSING A MOTION - The present disclosure provides an apparatus for sensing a motion. The apparatus comprises an optical fibre portion comprising a Bragg grating and an element for reducing an impact of an external force that is transversal to the Bragg grating. Further, the apparatus comprises a contact region arranged so that movement of a further region, that is in direct or indirect contact with the contact region and moves in a direction along a portion of the apparatus, causes movement of the optical fibre portion at the contact region. The apparatus also comprises a holder arranged for reducing movement of the optical fibre portion at a holding region when the optical fibre portion is moved at the contact surface. The apparatus is arranged so that movement of the contact region relative to the holding region causes a change in strain of the Bragg grating. | 11-10-2011 |
| 20120045165 | Magnetically Actuated Photonic Crystal Sensor - A magnetically actuated photonic crystal sensor is disclosed. An optical fiber comprises at least one photonic crystal means coupled to a first end thereof, and a magnetic material coupled to the at least one photonic crystal means. | 02-23-2012 |
| 20120070112 | OPTICAL FIBER SHEET AND BODY MOTION SENSOR - A body motion sensor, such as an SAS diagnostic device, with which a subject can be examined in a state close to that in an ordinary living environment and it is possible to clearly discriminate between an apnea state and a hypopnea state by means of a relatively simple analytical method; and an optical fiber sheet suitable for use in the sensor. The body motion sensor, such as an SAS diagnostic device, comprises a light source such as an LED, an optical fiber sheet, and an analysis unit that determines fluctuations in the quantity of light outputted from the optical fiber sheet and detects motions of the body. As the optical fiber sheet, use is made of an optical fiber sheet comprising a planar object, such as a fabric, paper, or plastic sheet, and graded-index optical quartz fibers directly or indirectly disposed thereon or affixed thereto When the sheet is produced, it is preferred to use a pressure-sensitive adhesive sheet comprising a sheet support, such as paper or fabric, and a pressure-sensitive adhesive layer formed thereon. | 03-22-2012 |
| 20120076453 | Intrusion Detection System for Use on Single Mode Optical Fiber Using a Simplified Polarimeter - A telecommunications optical fiber is secured against intrusion by detecting manipulation of the optical fiber prior to an intrusion event. This can be used in a non-locating system where the detection end is opposite the transmit end or in a locating system which uses Fresnel reflections and Rayleigh backscattering to the transmit end to detect and then locate the motion. The Rayleigh backscattering time sliced data can be stored in a register until an intrusion event is detected. The detection is carried out by a polarization detection system which includes an optical splitter which is manufactured in simplified form for economic construction. This uses a non-calibrated splitter and less than all four of the Stokes parameters. It can use a polarimeter type function limited to linear and circular polarization or two linear polarizers at 90 degrees. | 03-29-2012 |
| 20120087619 | OPTICAL FIBRE CABLE FOR DISTRIBUTED FIBRE SENSING - An optical fibre cable for distributed fibre sensing of fluid pressure is disclosed. There are also disclosed a method and an apparatus for distributed fibre sensing of fluid pressure using the optical fibre cable. The optical fibre cable is adapted for distributed pressure sensing, and comprises: one or more optical fibres ( | 04-12-2012 |
| 20120243822 | GETTING-ON/OFF DETERMINATION APPARATUS AND GETTING-ON/OFF DETERMINATION METHOD - A getting-on/off determination apparatus determines rider's getting-on/off for an inverted two-wheel vehicle that travels while maintaining the inverted state. The getting-on/off determination apparatus includes an optical fiber laid in a step portion that a rider gets on/off, a light emitting unit that emits detection light and is connected to one end of the optical fiber, a light receiving unit that receives the detection light emitted from the light emitting unit and is connected to another end of the optical fiber, at least one transmitted light varying portion that varies an amount of transmitted light of the detection light passing through the optical fiber in conjunction with a vertical displacement of the step portion that occurs when the rider gets on/off the inverted two-wheel vehicle, and a determination unit that determines getting-on/off of the rider based on an amount of the detection light received by the light receiving unit. | 09-27-2012 |
| 20120308174 | WELL-BORE SENSING - A sensor system for use in a wellbore has a fiber-optic cable and a tool connected to the cable and moveable through the well bore. The tool in turn has an array of members arranged around a circumference of the tool and extending radially outwardly to contact an inner surface of the wellbore or a tube in the wellbore, and an array of Bragg grating fiber-optic sensors each configured such that movement of a respective sensing element results in a measurable value or change in the respective sensor. The sensors are arranged to sense a common physical parameter to be measured at a plurality of discrete positions around a circumference of the wellbore or the tube in the wellbore. | 12-06-2012 |
| 20120314988 | ROTATED SINGLE OR MULTICORE OPTICAL FIBER - An apparatus for estimating a shape, the apparatus including: an optical fiber configured to conform to the shape and having a first core offset from a centerline of the optical fiber, the first core having an optical characteristic configured to change due to a change in shape of the optical fiber wherein a change in the optical characteristic is used to estimate the shape. A method for estimating a shape is also disclosed. | 12-13-2012 |
| 20120321243 | OPTICAL FIBER INSTRUMENT SYSTEM FOR DETECTING AND DECOUPLING TWIST EFFECTS - An instrument system that includes an elongate body, an optical fiber, and a detector is provided. The elongate body is capable of being twisted. The optical fiber includes a first portion coupled to the elongate body and a second portion having a curved shape adapted to reduce transfer of twisting or bending from the elongate body to the second portion, the second portion having a strain sensor provided thereon. The detector is coupled to the optical fiber and adapted to receive a signal from the strain sensor. | 12-20-2012 |
| 20130034324 | OPTICAL FIBER SENSOR AND METHOD FOR ADHERING AN OPTICAL FIBER TO A SUBSTRATE - An optical fiber sensing apparatus includes: a substrate configured to deform in response to an environmental parameter; an optical fiber sensor including a core having at least one measurement location disposed therein and a protective coating surrounding the optical fiber sensor, the protective coating made from a polyimide material; and an adhesive configured to adhere the optical fiber sensor to the substrate, the adhesive made from the polyimide material. | 02-07-2013 |
| 20130039613 | POSITION SENSOR USING FIBER BRAGG GRATINGS TO MEASURE AXIAL AND ROTATIONAL MOVEMENT - A sensor is disclosed herein. The sensor includes a fiber operable to communicate a light wave. The sensor also includes at least first and second Fiber Bragg Gratings disposed along the fiber. The sensor also includes a structure operable to be deformed in a plane of deformation. The at least first and second Fiber Bragg Gratings are disposed on opposite sides of the structure in the plane of deformation. The sensor also includes an interrogation unit operable to receive first and second signals corresponding to first and second wavelengths from the at least first and second Fiber Bragg Gratings. The first signal is associated with the first Fiber Bragg Grating and the second signal is associated with the first Fiber Bragg Grating. The sensor also includes a processor operably to derive a difference between the wavelengths of the first and second signals and compare the difference with data correlating wavelength differences to extents of deformation of the structure to yield a current extent of deformation. | 02-14-2013 |
| 20130094798 | Monitoring Structural Shape or Deformations with Helical-Core Optical Fiber - A method, apparatus and system for determine a parameter of a structure is disclosed. A fiber optic cable is coupled to a member. The fiber optic cable includes at least a first core helically arranged in the fiber optic cable that includes at least a first sensor and a second sensor. A first measurement related to the parameter is obtained at the first sensor, and a second measurement at the second sensor related to the parameter is obtained at the second sensor. A difference between the first and second measurements is used to determine the parameter. | 04-18-2013 |
| 20130294720 | SYSTEM AND METHOD FOR MAKING DISTRIBUTED MEASUREMENTS USING FIBER OPTIC CABLE - A method for determining the physical location of a fiber optic channel in a fiber optic cable comprises the steps of a) providing at least one location key having a known physical location, b) establishing the location of the location key with respect to the fiber optic channel, and c) using the location information established in step b) to determine the physical location of the channel. The location key may comprises an acoustic source, a section of fiber optic cable that is acoustically masked, or at least one magnetic field source and step b) comprises using a Lorentz force to establish the location of the magnetic field source with respect to the fiber optic channel. | 11-07-2013 |
| 20130308895 | SIDE-HOLE CANE WAVEGUIDE SENSOR - A side-hole optical cane for measuring pressure and/or temperature is disclosed. The side-hole cane has a light guiding core containing a sensor and a cladding containing symmetrical side-holes extending substantially parallel to the core. The side-holes cause an asymmetric stress across the core of the sensor creating a birefringent sensor. The sensor, preferably a Bragg grating, reflects a first and second wavelength each associated with orthogonal polarization vectors, wherein the degree of separation between the two is proportional to the pressure exerted on the core. The side-hole cane structure self-compensates and is insensitive to temperature variations when used as a pressure sensor, because temperature induces an equal shift in both the first and second wavelengths. Furthermore, the magnitude of these shifts can be monitored to deduce temperature, hence providing the side-hole cane additional temperature sensing capability that is unaffected by pressure. Additionally, the side-hole cane can be used to measure a differential pressure between a first pressure ported to the side-holes and a second external pressure. | 11-21-2013 |
| 20130330032 | FIBER OPTIC SWITCH - This disclosure is of a fiber optic switch, where an actuated plunger causes a snap-action mechanism to change rapidly from a first state to a second state and place a loaded member from a first strain condition into a second strain condition where the two conditions are substantially different. A strain sensor mounted on the loaded member senses the strain of the loaded member and transmits a corresponding signal on a fiber optic cable. | 12-12-2013 |
| 20140050438 | IMPACT SENSOR OF ACTIVE HOOD SYSTEM - An impact sensor of an active hood system includes a rear member, optical fiber sensors, a front member and membrane switch. Each of the optical fiber sensors is disposed on upper and lower portions of a front of the rear member and senses an impact force delivered from a bumper at the time of a crash with a pedestrian. The front member is disposed at the front of the rear member and has a protrusion part pressing the optical fiber sensors by the impact force delivered from the bumper at the time of the crash with the pedestrian. The membrane switch is disposed between the front member and the optical fiber sensor, divided into a plurality of regions from a left of the front member to a right thereof, and configured to sense a region which is pressed when the pedestrian crashes with the region. | 02-20-2014 |
| 20140112614 | ELECTRICAL LINE FOR A MOTOR VEHICLE - An electrical line ( | 04-24-2014 |
| 20140112615 | CO-REGISTRATION OF CORES IN MULTICORE OPTICAL FIBER SENSING SYSTEMS - A twisted, multicore fiber communicates light input to each core to an output. The twisting mitigates relative time delays of the input light traveling through each of the cores in the multicore fiber to the output caused by bending of that multicore fiber. An example application is in an optical network that includes an optical input terminal and an optical sensor connected by a twisted multicore connecting fiber. One example of twisted multicore optical fiber is helically-wrapped, multicore fiber. | 04-24-2014 |
| 20140140656 | Method to utilize string-strain-change induced by a transverse force and its application in fiber Bragg grating accelerometers - When a transverse force is applied to a stretched string that is fixed by its two ends, the string bends and the strain of the string increases to balance the transverse force. As a result, the axial force along the string can increase much more than the transverse force applied. | 05-22-2014 |
| 20140286604 | ENDO-MICROSCOPIC PROBE BASED ON NON-RESONANT SCANNING METHOD USING OPTICAL FIBER - Disclosed is an endo-microscopic probe based on a non-resonant scanning method using an optical fiber which includes a housing configured to have a specific size, an optical fiber placed within the housing and configured to transfer a light source, a tubular piezoelectric element configured to surround the optical fiber within the housing, include a guide unit for guiding a movement of the optical fiber at the end of the tubular piezoelectric element, and provide a deformation value according to a deformation amount to the optical fiber through the guide unit using an external power source, and a lens unit placed within the tubular piezoelectric element, fixed to an end of the housing, and configured to transfer light output from an end of the optical fiber to a sample. | 09-25-2014 |
| 20140321799 | Fiber-Grating Sensors Having Longitudinal-Strain-Inducing Jackets and Sensor Systems and Structures Including Such Sensors - A sensor comprising an optical fiber that includes a Bragg grating and a longitudinal-strain-inducing (LSI) jacket for inducing longitudinal strain into the optical fiber as a function of a transverse load, i.e., pressure or force. As the LSI jacket induces strain into the optical fiber, the fiber grating deforms, thereby changing the character of light reflected from the grating. The changes in character of the reflected light can be measured using suitable optical instrumentation. Additional physical characteristics that can be measured/sensed using an LSI-jacket-based sensor include moisture content/presence, chemical content/presence, and temperature. A transverse-load-sensing sensor can include transverse-load-applying structures that compress the LSI jacket under transverse load, causing the jacket to controllably elongate and thereby induce longitudinal strain into the optical fiber. Chemical and moisture LSI jackets can comprise materials that swell in the presence of the chemical or moisture. | 10-30-2014 |
| 20140321800 | POSITION SENSOR USING FIBER BRAGG GRATINGS TO MEASURE AXIAL AND ROTATIONAL MOVEMENT - A sensor is disclosed herein. The sensor includes a fiber operable to communicate a light wave. The sensor also includes at least first and second Fiber Bragg Gratings disposed along the fiber. The sensor also includes a structure operable to be deformed in a plane of deformation. The at least first and second Fiber Bragg Gratings are disposed on opposite sides of the structure in the plane of deformation. The sensor also includes an interrogation unit operable to receive first and second signals corresponding to first and second wavelengths from the at least first and second Fiber Bragg Gratings. The first signal is associated with the first Fiber Bragg Grating and the second signal is associated with the second Fiber Bragg Grating. The sensor also includes a processor operable to derive a difference between the wavelengths of the first and second signals and compare the difference with data correlating wavelength differences to extents of deformation of the structure to yield a current extent of deformation. | 10-30-2014 |
| 20140334767 | APPARATUS AND METHOD FOR MEASURING BENDING AND TOUCH USING OPTICAL WAVEGUIDE - An apparatus and method for measuring bending of an object, a position of an item touching the object, and a shearing force of the item using an optical waveguide may include a frequency measurer to measure a frequency of light reflected from a grating of an optical waveguide, and a bending measurer to determine bending of an object to which the optical waveguide is attached using the frequency. | 11-13-2014 |
| 20150049981 | FIBER OPTIC SENSING APPARATUS AND METHOD FOR SENSING PARAMETERS INVOLVING DIFFERENT PARAMETER MODALITIES - An optical-based sensing apparatus and method are provided. A sensing apparatus ( | 02-19-2015 |
| 20150098673 | GEO-LOCATING POSITIONS ALONG OPTICAL WAVEGUIDES - A method of correlating physical locations with respective positions along an optical waveguide can include transmitting to the waveguide a signal including an indication of the transmitting location, and the waveguide receiving the signal. A system for correlating a physical location with a position along an optical waveguide can include a transmitter which transmits to the optical waveguide a signal including an indication of the transmitter location, and a computer which correlates the location to the position, based on the signal as received by the waveguide. A method of determining a position along an optical waveguide at which a signal is transmitted can include modulating on the signal an indication of a transmission location, and transmitting the signal to the waveguide, thereby causing vibration of the waveguide. | 04-09-2015 |
| 20150362669 | BAND-GAP TUNABLE ELASTIC OPTICAL MULTILAYER FIBERS - The rolled photonic fibers presents two codependent, technologically exploitable features for light and color manipulation: regularity on the nanoscale that is superposed with microscale cylindrical symmetry, resulting in wavelength selective scattering of light in a wide range of directions. The bio-inspired photonic fibers combine the spectral filtering capabilities and color brilliance of a planar Bragg stack compounded with a large angular scattering range introduced by the microscale curvature, which also decreases the strong directional chromaticity variation usually associated with flat multilayer reflectors. Transparent and elastic synthetic materials equip the multilayer interference fibers with high reflectance that is dynamically tuned by longitudinal mechanical strain. A two-fold elongation of the elastic fibers results in a shift of reflection peak center wavelength of over 200 nm. | 12-17-2015 |
| 20160040527 | STRAIN LOCKED FIBER OPTIC CABLE AND METHODS OF MANUFACTURE - An embodiment of a method of manufacturing a fiber optic cable includes selecting a cable support structure configured to support an optical fiber sensor, adhering the optical fiber sensor to the cable support structure by applying a temporary adhesive, and installing a protective layer around the cable support structure and the temporarily adhered optical fiber sensor. The method further includes removing a bond between the optical fiber sensor and the temporary adhesive, wherein removing the bond includes injecting a debonding material into a space formed between the cable support structure and the protective layer, and injecting a permanent adhesive into the space, the permanent adhesive configured to immobilize the optical fiber sensor relative to the protective layer and allow strain to be transferred from the protective layer to the optical fiber sensor. | 02-11-2016 |
| 20160116331 | FIBER OPTIC CABLE FOR DISTRIBUTED ACOUSTIC SENSING WITH INCREASED ACOUSTIC SENSITIVITY - Methods and apparatus for performing Distributed Acoustic Sensing (DAS) using fiber optics with increased acoustic sensitivity are provided. Acoustic sensing of a wellbore, pipeline, or other conduit/tube based on DAS may have increased acoustic sensitivity through fiber optic cable design and/or increasing the Rayleigh backscatter property of a fiber's optical core. Some embodiments may utilize a resonant sensor mechanism with a high Q coupled to the DAS device for increased acoustic sensitivity. | 04-28-2016 |
| 20160161632 | GEO-LOCATING POSITIONS ALONG OPTICAL WAVEGUIDES - A method of correlating physical locations with respective positions along an optical waveguide can include transmitting to the waveguide a signal including an indication of the transmitting location, and the waveguide receiving the signal. A system for correlating a physical location with a position along an optical waveguide can include a transmitter which transmits to the optical waveguide a signal including an indication of the transmitter location, and a computer which correlates the location to the position, based on the signal as received by the waveguide. A method of determining a position along an optical waveguide at which a signal is transmitted can include modulating on the signal an indication of a transmission location, and transmitting the signal to the waveguide, thereby causing vibration of the waveguide. | 06-09-2016 |
| 20160161633 | GEO-LOCATING POSITIONS ALONG OPTICAL WAVEGUIDES - A method of correlating physical locations with respective positions along an optical waveguide can include transmitting to the waveguide a signal including an indication of the transmitting location, and the waveguide receiving the signal. A system for correlating a physical location with a position along an optical waveguide can include a transmitter which transmits to the optical waveguide a signal including an indication of the transmitter location, and a computer which correlates the location to the position, based on the signal as received by the waveguide. A method of determining a position along an optical waveguide at which a signal is transmitted can include modulating on the signal an indication of a transmission location, and transmitting the signal to the waveguide, thereby causing vibration of the waveguide. | 06-09-2016 |
| 20220139595 | Submarine Power Cable With Curvature Monitoring Capability - A multi-phase submarine power cable including: a plurality of power cores arranged in a stranded configuration, and a curvature sensor including: an elastic elongated member, and a plurality of Fibre Bragg Grating, FBG, fibres, each FBG fibre extending axially along the elongated member at a radial distance from the centre of the elongated member; wherein the elongated member extends between the stranded power cores along a central axis of the multi-phase submarine power cable. | 05-05-2022 |
