| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 356350500 | By light interference detector (e.g., interferometer) | 24 |
| 20080204707 | Monitoring device for rotating body - The present invention relates to a monitoring device for a rotating body, which can accurately measure signals from a fiber Bragg grating sensor provided on the rotating body by compensating a transmission loss variation and a distortion of the sensor signals. A rotation-side optical fiber has at least one deformation sensor at a portion thereof and a reference sensor at one end thereof. The sensors are made by forming a Bragg grating in the rotation-side optical fiber. A fixed-side optical fiber is mounted to the fixed body so as to be opposed to the one end of the rotation-side optical fiber. A signal processing unit detects a deformation of the rotating body by subtracting a signal corresponding to the light reflected from the reference sensor from a signal corresponding to the light reflected from the deformation sensor. | 08-28-2008 |
| 20080212067 | INSPECTION AND STRENGTH MEASUREMENT OF SOLDER AND STRUCTURAL JOINTS USING LASER GENERATED STRESS WAVES - Methods and apparatus are disclosed for direct measurement of the tensile strength of joints with use of laser spallation. A laser pulse is directed at a surface in communication with a solder joint, generating a stress wave to separate the solder ball from its underlying structure. The solder joint may be measured either prior to joining of a PCB board or CSP package, or after they have been joined. The joints for testing may be prepared by polishing either the PC board or the CSP package to expose the desired solder joint for testing. The tensile strength of the embedded joints may also be measured in-situ. | 09-04-2008 |
| 20090079961 | Brillouin Spectral Measuring Method and Brillouin Spectral Measuring Apparatus - The present invention relates to a Brillouin spectrum measuring method and measuring apparatus that have a structure for more accurately measuring the parameters of Brillouin spectra at predetermined sections of an optical fiber. The measuring method comprises an optical fiber section including first and second optical fibers that are serially connected via a connection portion. The first and second optical fibers have a Brillouin spectrum for which the difference between the peak frequencies in a predetermined temperature and predetermined strain-applied state for which the respective usage environments are assumed is equal to or more than a predetermined frequency difference. In the measuring method, a Brillouin spectrum which is obtained in accordance with pumping light supplied to the optical fiber section is measured, and a point of connection between the first and second optical fibers is specified on the basis of the measurement data for the measured Brillouin spectrum. | 03-26-2009 |
| 20110032511 | SYSTEM AND METHOD TO MEASURE NANO-SCALE STRESS AND STRAIN IN MATERIALS - A system for measuring stress and strain in a sample is provided. The system includes a sample holder operable to support the sample; a stress inducing assembly operable to apply force to a selected location on the sample to deform the sample by a selected distance in a range from about 0.1 angstrom to about a millimeter; and an interferometer operable to determine a surface topography of the deformed sample at a resolution in a range from about 0.1 angstrom to about a micron. | 02-10-2011 |
| 20110032512 | FLOATING-ELEMENT SHEAR-STRESS SENSOR - A shear-stress sensing system can include a floating element whose displacement can be detected through use of optical measurements. The system can utilize high temperature materials to deliver the optical signal to the structure to be measured, which can also utilize high temperature materials. In one embodiment, an intensity modulation or phase modulation of a reflected signal can be measured to determine the shear stress. In another embodiment, a Moire fringe pattern can be used to determine the shear stress. | 02-10-2011 |
| 20110085156 | DETECTING PARTICULATE CONTAMINANTS IN A FLUID - A vibration detector ( | 04-14-2011 |
| 20110273701 | METHODS FOR CHARACTERIZATION OF THE MECHANICAL PROPERTIES OF THIN FILMS AND TEST STRUCTURES FOR PERFORMING THE SAME - A test structure allows one or more deposited thin film layers to be moved such that mechanical properties of the thin film layer or layers may be determined. Methods for characterizing the mechanical properties of the deposited thin film layer include the determination of a transition voltage of the movable thin film layer in the test structure, or the mechanical stiffness of the movable layer, and/or a determination of residual stress within the movable layer. Methods may also include the determination of creep rate or fatigue, as well as the variance in mechanical properties of the movable layer at various temperatures. Test structures used with the testing methods may include structures which interferometrically modulate incident light, enabling electrical or optical determination of the state of the test structures. | 11-10-2011 |
| 20110299064 | DEFORMATION MEASURING APPARATUS AND DEFORMATION MEASURING METHOD - An apparatus and a method capable of measuring large deformation with a high accuracy and dynamically, using speckle interference, utilizes an optical path where one laser beam out of two laser beams becomes non-collimated light and a plane parallel transparent plate, and can form carrier fringes. More specifically, the transparent plate is arranged on the optical path where the non-collimated light is formed, or is removed from the optical path, or a refractive index, or a thickness of the transparent plate arranged on the optical path, or a tilt angle relative to an optical axis is changed. The phase analysis can be performed from fringe images corresponding to the deformation, by performing repetitively the above-described processing and acquisition of the speckle interference pattern. | 12-08-2011 |
| 20110310378 | INTERFEROMETRIC MEASUREMENT WITH CROSSTALK SUPPRESSION - An interferometric measurement system suppresses cross talk between optical waveguides used to measure one or more parameters. A first interferometric measurement channel coupled to a first waveguide, and a second interferometric measurement channel coupled to a second waveguide. At least one of the channels includes a reference light path in addition to the first and second waveguides. A reference path optical delay is associated with the reference light path, a first optical delay is associated with the input portion of at least one of the first and second interferometric measurement channels, and a second optical delay is associated with an output portion of the one interferometric measurement channel. A value of the first optical delay and a value the second optical delay are chosen to suppress crosstalk associated with the other of the first and second interferometric measurement channels in the one interferometric measurement channel over a predetermined length of the first waveguide. Signals corresponding to the reference light path and the first and second interferometric measurement channels are processed to measure one or more parameters. | 12-22-2011 |
| 20110317148 | REGISTRATION OF AN EXTENDED REFERENCE FOR PARAMETER MEASUREMENT IN AN OPTICAL SENSING SYSTEM - An interferometric measurement system measures a parameter using at least one optical waveguide. A memory stores reference interferometric pattern data associated with a segment of the optical waveguide. Interferometric detection circuitry detects and stores measurement interferometric pattern data associated with the segment of the optical waveguide during a measurement operation. A spectral range of the reference interferometric pattern of the optical waveguide is greater than a spectral range of the measurement interferometric pattern of the optical waveguide. A processor shifts one or both of the measurement interferometric pattern data and the reference interferometric pattern data relative to the other to obtain a match and to use the match to measure the parameter. An example parameter is strain. | 12-29-2011 |
| 20120033198 | High Speed Autofocus Interferometric Inspection Systems And Methods - High speed autofocus interferometric inspection systems and methods are discussed in this application. In accordance with some embodiments, an inspection system can generally include a laser module, an interferometer module, and a system controller. The laser can produce laser pulses to excite a device such as a silicon wafer, chip capacitor or chip packaged/silicon die containing a plurality of solder bumps into vibration. The interferometer module can be disposed to receive reflected laser energy from the device to sense vibration displacements created in the device with the laser pulses. The system controller to receive vibration data from the interferometer, the system controller configured to output a control signal for adjusting a relative distance and position between the laser module and the device. Other aspects, features, and embodiments are also claimed and discussed. | 02-09-2012 |
| 20130250278 | PORTABLE HIGH-RESOLUTION NON-CONTACT MODULAR SENSOR FOR SURFACE STRAIN MEASUREMENT - A portable optical sensor for measuring surface strain in an object, such as pre-stressed concrete articles, is provided. The sensor is a modular device comprising at least first and second modules, each of which includes a laser and image sensor. When placed adjacent to the object, the laser of each module illuminates respective, spaced-apart areas of the object's surface and each module's image sensor captures at least a portion of the light reflected from the illuminated area and generates a speckle image of the area. Speckle images of the areas taken at various times and/or under various object stress conditions are compared to arrive at a surface strain measurement for the object. | 09-26-2013 |
| 20130293868 | DETECTION OF FOREIGN OBJECT IN PROXIMTY OF SURGICAL END-EFFECTOR - An optical detection tool employs a surgical end-effector ( | 11-07-2013 |
| 20140022530 | STRUCTURE MONITORING - A method and apparatus for monitoring a structure using an optical fiber based distributed acoustic sensor (DAS) extending along the length of the structure. The DAS is able to resolve a separate acoustic signal with a spatial resolution of 1 m along the length of the fibre, and hence is able to operate with an acoustic positioning system to determine the position of the riser with the same spatial resolution. In addition, the fiber can at the same time also detect much lower frequency mechanical vibrations in the riser, for example such as resonant mode vibrations induced by movement in the surrounding medium. By using vibration detection in combination with acoustic positioning then overall structure shape monitoring can be undertaken, which is useful for vortex induced vibration (VIV) visualisation, fatigue analysis, and a variety of other advanced purposes. The structure may be a sub-sea riser. | 01-23-2014 |
| 20140111789 | Optical Fiber Coupled Photonic Crystal Slab Strain Sensor, System And Method Of Fabrication And Use - The present disclosure is generally directed to a strain sensor, system and method of fabrication and use that includes an optical fiber, an optical signal generator that transmits an optical signal through the optical fiber, at least two photonic crystal slabs within the optical fiber separated by a first segment of optical fiber, a photo-detector that detects a reflected optical signal from the at least two photonic crystal slabs, and a processor that computes a mechanical strain over the first segment of optical fiber based on the reflected optical signal detected by the photo-detector. | 04-24-2014 |
| 20140293269 | Deformation Measurement Sensor Operating In A Hostile Environment And Including An Optical Movement Measurement Module, And Measurement System Using Said Sensor - Deformation measurement sensor operating in a hostile environment and including an optical movement measurement module, and measurement system using said sensor. | 10-02-2014 |
| 20150300961 | Electronic Device Having Components With Stress Visualization Features - An electronic device may have housing structures, electrical components, and other electronic device structures. Stress sensing structures may be formed using coatings on these electronic device structures. Stress sensing structures may have strip-shaped links that extend between pads or may be formed from blanket films. A stress sensing coating may be formed from a transparent thin film. The transparent thin film may be illuminated with monochromatic light while a video camera captures video images of resulting optical interference patterns. The video images may be captured during a test in which a device structure is exposed to stress from an impact between the device and an external object. Stress sensing coatings may also be formed from layers of material that develop cracks upon exposure to stress. Stress sensing structures may be used to evaluate stress during tests and to monitor stress during normal device use. | 10-22-2015 |
| 20150316427 | OPTICAL FIBER COUPLED PHOTONIC CRYSTAL SLAB STRAIN SENSOR, SYSTEM AND METHOD OF FABRICATION AND USE - The present disclosure is generally directed to a strain sensor, system and method of fabrication and use that includes an optical fiber, an optical signal generator that transmits an optical signal through the optical fiber, at least two photonic crystal slabs within the optical fiber separated by a first segment of optical fiber, a photo-detector that detects a reflected optical signal from the at least two photonic crystal slabs, and a processor that computes a mechanical strain over the first segment of optical fiber based on the reflected optical signal detected by the photo-detector. | 11-05-2015 |
| 20150330848 | OPTICAL DEVICE UTILIZING FIBER BRAGG GRATING AND NARROWBAND LIGHT WITH NON-BRAGG WAVELENGTH - In certain embodiments, an optical device and a method of use is provided. The optical device includes a fiber Bragg grating having a substantially periodic refractive index modulation along a length of the fiber Bragg grating. The fiber Bragg grating has a power transmission spectrum with a plurality of local transmission minima, wherein each pair of neighboring local transmission minima has a local transmission maximum therebetween. The local transmission maximum has a maximum power at a transmission peak wavelength. The optical device further includes a narrowband optical source in optical communication with a first optical path and a second optical path. The narrowband optical source is configured to generate light having a wavelength at or in the vicinity of a local transmission maximum or at or in the vicinity of a wavelength at which the power transmission spectrum has a maximum slope between a local transmission maximum and either one of two local transmission minima neighboring the local transmission maximum. | 11-19-2015 |
| 20150362386 | FIBER OPTIC SENSOR SYSTEM AND METHOD - A fiber Bragg grating (FBG) is used to measure strain. An optical fiber is used with a grating that comprises periodic spatial variations with mutually different first and second spatial frequencies. The wavelength of a first and second light source is swept over a first and second wavelength range that contain first and second Bragg reflection wavelengths corresponding to first and second spatial frequencies respectively. Light from the light sources is supplied to the optical fiber and to a reference branch. The reference branch contains an interferometer and a first and second filter having a transmission or reflection peak in the first and second wavelength range respectively. Time points of first and second peaks in the reflection of the light from the first and second light source by the optical fiber or detected during said sweeping. A count is made of periods of output of the interferometer, between the time points of detection of the first and second peaks and time points of detection of peaks from the first and second filter. The strain is solved from an equation that relates the variations of the temperature and the strain as shown by the counts. | 12-17-2015 |
| 20160054116 | Scanning interferometry technique for through-thickness evaluation in multi-layered transparent structures - A multi-layer transparent composite detection technique includes producing two beams from a single, low-coherence source, a test beam and a reference beam, and scanning the reference beam to determine, with high precision, the depths of flaws (e.g., delaminations, bubbles, inclusions or other reflective or scattering objects) within a specimen or test object. The techniques combine light back-reflected or back-scattered from an internal flaw or interface with light in a reference path to identify such features and locations. | 02-25-2016 |
| 20160061672 | INTERFEROMETRIC OPTICAL FIBER SENSOR SYSTEM AND INTERFEROMETRIC OPTICAL FIBER SENSOR HEAD - An interferometric optical fiber sensor system comprises a light source, a first coupler optically connected to the light source, a first optical path for inputting measurement light, a second optical path for inputting reference light, a second coupler for combining the first and second optical paths together, a photodetector for measuring modulation of the measurement light and the reference light, and a coil for modulating with a stress exerted thereon the measurement light and the reference light. The first optical path has an optical length equal to that of the second optical path. The first optical path has a first delay line, while the second optical path has a second delay line. The coil is disposed between the first delay line and the second coupler and between the second delay line and the first coupler. | 03-03-2016 |
| 20160377528 | TESTING OF AN INDUSTRIAL STRUCTURE - A method and a device for analyzing a structure by tomography and diffuse acousto-elastic field correlation are provided. An optical fiber comprising a plurality of measurement points of FBG (Fiber Bragg Grating) type, comprising sensors of Bragg grating type, is deployed in or on the structure to be analyzed. The method comprises the emission of light, into the optical fiber, and the measurement by correlation for each pair of FBG sensors. In a development, a prior imaging of the structure is performed by reconstruction of the velocities of propagation. Other developments comprise: the determination of the positions of the FBG sensors, the calibration of the tomography, the rosette configuration of the sensors forming the measurement points, the use of a plurality of optical fibers, of multiplexers, of lasers, of optical circulators, of omnidirectional optical sensors, of active noise sources, such as piezoelectric transducers, incorporated or not in the structure. | 12-29-2016 |
| 20180024035 | Apparatus for In-Line Testing and Surface Analysis on a Mechanical Property Tester | 01-25-2018 |
