Abstract: An elastic-wave monitoring device includes an optical system which is arranged so that a circularly polarized light from a light source is incident to a measured object and a light beam from the measured object passes through a polarizing filter to a photodetector. A detection unit detects periodic fluctuation components of an output signal of the photodetector. In the elastic-wave monitoring device, the polarizing filter is arranged to have a polarization transmission axis directed to one of directions of principal axes of an ellipse formed by intersections of an index ellipsoid of the measured object and a plane perpendicular to an incidence direction of the light beam and passing through an origin of the index ellipsoid.

Abstract: A piezoelectric sensor (7) is dedicated to making a precise measurement of the light amplitude of pulses (2) from a laser (1), so that quantitative measurements such as photo-acoustic spectroscopy can be used to precisely measure the concentration of some bodies in a solution.

Abstract: A method and system are provided for measurement of vibration of an object utilizing a non-contact imaging sensor such as a video camera. An object which does not already have a pair of spaced-apart marks is marked with two parallel lines spaced apart from one another a known, nominal distance. The two lines are perpendicular to an imaging axis of the camera. As such, when the object with the parallel lines is moved toward or away from the video camera, the lines on the object appear to move as two parallel lines in the image plane of the camera. As the object moves or vibrates along the imaging axis, the nominal image plane distance between the two lines changes. This apparent change in the distance between the parallel lines in the image plane is calibrated to the physical movement of the object in space due to deformation or rigid body motions.

Abstract: A two-dimensional ultrasonic probe has a transmitting function of an ultrasonic signal without electric interconnection of a numerous number of microcomponents and without increase in crosstalk and electric impedance. This probe includes an optical fiber array having a plurality of optical fibers to which light generated from a light source is made incident, a plurality of ultrasonic detecting elements, formed at one ends of the respective optical fibers, for modulating incident light via the optical fibers on the basis of the ultrasonic signal to be applied, and an ultrasonic transmitting element using a piezoelectric element.

Abstract: A method for determining the thickness and other properties of a metal layer comprising producing an acoustic wave at a first frequency in the metal layer with a first laser beam, measuring the angle of diffraction of a second laser beam from the acoustic wave, and calculating the wavelength of the acoustic wave and thickness of the metal layer from the angle of diffraction.

Abstract: Workstation, apparatuses and methods for the high-throughput synthesis, screening and/or characterization of combinatorial libraries. The invention relates to an array, which permits various high-throughput methods for synthesis, screening and/or characterization in the same array, without requiring sample transfer from the array. In a preferred embodiment, the synthesis, screening, and/or characterization steps are carried out in a highly parallel fashion, where more than one compound is synthesized, screened, and/or characterized at the same time. The invention may be practiced at the microscale. The array may comprise thermal channels, for regulating the temperature of the wells in the array. The wells of the array may comprise a membrane, which is used in various screening and characterization methods. The invention also relates to a covered array, comprising the array and an array cover, as well as an apparatus comprising the array, which comprises the array, an array cover and a stage.

Abstract: A method serves for detecting the touch contact of an operator-controlled element of a machine by a user. In order to be able to continuously and with great safety and meaning carry out the detection, it is suggested that an actual vibration characteristic (FR) of the operator-controlled element is detected during operation, which changes in dependence upon a touch contact of the operator-controlled element by a user, and is compared to at least one desired vibration characteristic (FR0), which is present in a defined state of the operator-controlled element (34, 42), and an announcement (48, 52) takes place in dependence upon the result of the comparison.

Abstract: A micro-doppler microscope for providing an indication of the vibration of a target. An input laser beam is received by a beamsplitter that divides the input laser beam into a transmitted portion and a reflected portion. A first focusing optics focuses the transmitted portion onto a target, the target scattering a scattered portion thereof. This scattered portion is directed back through the first focusing optics, and reflected off the beamsplitter. Second focusing optics is positioned to receive the scattered portion from the beamsplitter and for focusing the scattered portion. A planar mirror is positioned to reflect the reflected portion of the input laser beam back through the beamsplitter and through the second focusing optics so that it is focused. A fast photodetector receives the focused scattered portion from the second focusing optics and the focused reflected portion from the second focusing optics. Both focused portions are focused on the same spot on the fast photodetector.

Abstract: A system and method for delivering a laser beam from a remote laser source through a gantry positioning system for performing ultrasonic testing on a test object. The invention provides for closed-loop error correction of a laser beam delivered through the gantry members of a gantry positioning system (GPS) to ensure unobstructed transmission of the laser beam as the GPS changes operates and changes shape. The invention provides for ultrasonic testing of a test object for identifying material defects by moving the end gantry member of the GPS thereby permitting data acquisition of the test object from various fields of view. The invention also provides for controlling the divergence of the laser beam used for ultrasonic testing.

Abstract: A micro-doppler microscope for providing an indication of the vibration of a target. An input laser beam is received by a beamsplitter that divides the input laser beam into a transmitted portion and a reflected portion. A first focusing optics focuses the transmitted portion onto a target, the target scattering a scattered portion thereof. This scattered portion is directed back through the first focusing optics, and reflected off the beamsplitter. Second focusing optics is positioned to receive the scattered portion from the beamsplitter and for focusing the scattered portion. A planar mirror is positioned to reflect the reflected portion of the input laser beam back through the beamsplitter and through the second focusing optics so that it is focused. A fast photodetector receives the focused scattered portion from the second focusing optics and the focused reflected portion from the second focusing optics. Both focused portions are focused on the same spot on the fast photodetector.

Abstract: The invention provides an apparatus for measuring the physical properties of a sample by optically monitoring the response of the sample to illumination by ultrashort optical pulses. The apparatus is a common path optical interferometer of a Sagnac type that can measure physical properties at normal incidence, i.e., a single-arm Sagnac interferometer featuring two beam splitters. Measurement is performed in such a manner that a sample is excited by a beam of ultrashort optical pulses, and variations in intensity and phase of another optical beam are detected. This enables a wide range of measurement of physical properties such as thickness, sound velocity, and thermal properties of substances.

Abstract: The invention provides an apparatus for measuring the physical properties of a sample by optically monitoring the response of the sample to illumination by ultrashort optical pulses. The apparatus is a common path optical interferometer of a Sagnac type that can measure physical properties at normal incidence. The interferometer is a two-arm Sagnac interferometer featuring two beam splitters. Measurement is performed in such a manner that a sample is excited by a beam of ultrashort optical pulses, and variations in intensity and phase of another optical beam are detected. This enables a wide range of measurement of physical properties such as thickness, sound velocity, and thermal properties of substances.

Abstract: An apparatus for measuring the physical properties of a sample by optically monitoring the response of the sample to illumination by ultrashort optical pulses utilizes a common path optical interferometer of a Sagnac type that can measure physical properties at normal incidence. The interferometer is a two-arm Sagnac interferometer featuring three beam splitters. A sample is excited by a beam of ultrashort optical pulses, and variations in intensity and phase of another optical beam are detected. This enables a wide range of measurement of physical properties such as thickness, sound velocity, and thermal properties of substances.

Abstract: A method and an apparatus for non-contact and non-invasive characterization of a moving thin sheet and in particular of a paper web on a production line. The method uses a laser for the generation of sonic and ultrasonic waves in the thin sheet and a speckle insensitive interferometric device for the detection of these waves. The generation is performed in conditions to avoid damage impeding further use of the sheet. When the generation and detection spots overlap, the method provides a measurement of the compression modulus. When the generation and detection spots are separated by a known distance and plate waves (Lamb waves) are generated and detected, the method provides a measurement of the in-plane modulus and of the tension applied to the sheet. By detecting waves propagating in various directions, either by rotating the detection sensor head or multiplexing the signals provided by several detection or generation locations, the anisotropy of the in-plane modulus is determined.

Abstract: A performance measuring system for a rotating shaft comprises a first annular support assembly to be coupled adjacent to a first end of a rotating shaft inwardly of associated shaft bearings. A second annular support assembly is to be coupled adjacent to a second end of a rotating shaft inwardly of associated shaft bearings. A third annular support assembly is to be coupled to the rotating shaft between the first and second support assemblies. A laser source is mounted on the first annular support assembly. A laser detector is mounted on the second annular support assembly. First and second magnetic sensors for detecting the Earth's magnetic field are mounted respectively on the first and second annular support assemblies. An accelerometer is mounted on the third annular support assembly for generating a fourth detection signal.

Abstract: A method and system for processing laser vibrometry data are embodied in a processor configured to employ a statistical signal processing technique (e.g., a Bayesian processing technique) to process one or more mathematical models, laser vibrometry data for a system under observation, and prior information to generate estimates of parameters for the one or more mathematical models.

Abstract: A device for measuring and detecting at least one narcotic, such as heroin and cocaine, in a fluid is provided. The device functions by selectively binding vapors of a narcotic or a narcotic present in a liquid, e.g., blood, to a luminescent molecularly imprinted polymer. The polymer possesses a securely bound luminescent lanthanide ion, such as Eu3+, in a coordination complex that has been templated with a narcotic.

Abstract: A method and/or an apparatus for determining the dynamic response of a microstructure is disclosed. A piezocomposite ultrasonic transducer device formed of a piezoelectric material and a polymer material around said piezoelectric ceramic material is used to provide a pulsed bulk acoustic wave having a bandwidth of at least 20% to excite a microstructure. The microstructure is attached onto the transducer, and the pulsed bulk acoustic wave generated through the transducer in response to a pulse voltage excites the microstructure to vibrate. Meanwhile, the dynamic response of the microstructure can be monitored by a laser Doppler vibrometer, and shown by an oscilloscope.

Abstract: A method and apparatus are provided for performing non-contact inspection of large concrete structures such as dams. A phrased array acoustic source transmits an acoustic wave onto the concrete structure. A laser transmitter-receiver unit transmits a laser beam onto the surface of the structure such that the beam is modulated by the acoustic wave and reflected back to the receiver portion of the unit. The acoustic wave will be distorted by defects or anomalies in the concrete structure and this will affect the signal content of the received laser beam. The laser beam is ultimately converted into a two-dimensional image or a three-dimensional tomographic image for further processing.

Abstract: In an implantable sound receptor for hearing aids, the sound sensor is designed as an optical sensor (5) and arranged within the ear at a distance from the surface of a sound transmission part (3) capable of being excited to acoustic vibrations.

Abstract: An ultrasonic detection method and apparatus are suited for real-time collection of three-dimensional ultrasonic data.

Abstract: The invention relates to a method and device for simultaneously measuring multiple properties of a sample composed of multiple layers of films. The measurement features several steps. First, at least one source of excitation radiation irradiates the sample's surface to excite an acoustic mode. A probe source of radiation irradiates the acoustic mode and is diffracted off the surface of the sample to form a signal beam. A detector detects the acoustic mode to generate a signal beam, which is then analyzed to determine an acoustic frequency and an amplitude, a depth of modulation, or a decay constant. These properties are then further analyzed to determine of at least two properties (e.g., a thickness of two layers) of the sample.

Abstract: An ultrasonic detection method and apparatus are suited for real-time collection of three-dimensional ultrasonic data.

Abstract: The present invention provides a vibration measurement method and apparatus utilizing a self-mixing type laser Doppler vibrator meter. The vibration measurement method includes steps of: oscillating a laser beam of a predetermined wavelength and applying the laser beam to an object to be measured; mixing the reflected laser beam from the object and the oscillated laser beam for outputting a beat wave; calculating ratio of a beat wave amplitude for the turning point of the vibrating object, with respect to a predetermined reference amplitude; and calculating a displacement amount for the turning point of the vibrating object, according to the calculated ratio. This enables to detect the vibration of the object to be measured, with a high accuracy.

Abstract: Disclosed is a method for characterizing a sample having a structure disposed on or within the sample, comprising the steps of applying a first pulse of light to a surface of the sample for creating a propagating strain pulse in the sample, applying a second pulse of light to the surface so that the second pulse of light interacts with the propagating strain pulse in the sample, sensing from a reflection of the second pulse a change in optical response of the sample, and relating a time of occurrence of the change in optical response to at least one dimension of the structure.

Abstract: The invention is an apparatus that measures dirt density on steel plates, characterized by including a pulsed laser that impinges on the inspected plate, and a microphone that detects the sound produced by the sudden ablation of the dirt, the amplitude of the microphone signal being the measure of the dirt on the plate. The microphone is connected to an electronic signal processing system, which is a computer or a programmed digital processor that determines the average value and standard deviation of the signal over the number of hits specified by the operator.

Abstract: The present invention discloses a vibration measurement method and apparatus using a self-mixing type laser Doppler vibration meter. The vibration measurement method according to the present invention comprises: an inclination value calculation step S3 for calculating an ascending inclination and a descending inclination for each beat wave; and a turning point identification step S4 for identifying the turning point of a vibrating object according to the inclination change along the time axis.

Abstract: To enable vibration conditions of a measured object to be measured with high accuracy independently of a laser oscillating wavelength. A vibration measuring means includes a laser resonator for oscillating a laser beam and generating beat waves through self-mixture of a returning beam obtained when the oscillated emitted beam is reflected by the measured object with a beam oscillated and emitted when the returning beam is received, a modulated beat frequency generation controller 8 for providing the beat waves with a modulated beat frequency that is higher than a Doppler frequency that is superposed on the returning beam while varying depending on a speed of the measured object, and a signal processor 21 for executing signal processing on the beat waves generated by the self-mixture in the laser resonator and outputting a result of the processing as vibration information.

Abstract: A technique for measuring and selectively adjusting a clearance between a stationary object and desirably a rotating object includes a non-contact, sensing system having a sensor attachable to the stationary object, a mask having a predetermined sized viewport or aperture that sets or limits the sensing or operation of the sensor, and a controller. The sensor is operable for sensing within a field of view a portion of the rotating object and generating a signal in response thereto. The field of view varies in response to varying the clearance between the sensor and the second object. Desirably, the portion of the second object includes a varying pattern. The controller is operable to determine the clearance between the first object and the second object in response to the signal. In another embodiment, sensing system is operable to adjust the clearance by controller providing an electrical current to a resistive heating element in the thermally expandable portion of a plurality of segmented labyrinth seals.

Abstract: A method and an apparatus are provided for contact-free optical displacement and/or vibration measurement of an object, in which the object to be measured is scanned in the form of a grid. The position of the measurement points and the contour of the grid are freely selectable. Individual measurement point subquantities, to be analyzed respectively in correlation with one another, can be classified in different categories and analyzed as a function of the category to which they are assigned.

Abstract: According to an example embodiment of the present invention, a semiconductor device having conductive structure is analyzed using acoustic energy. Acoustic energy is generated in the device, and a resulting acoustic wave is detected. Using the detected wave, an index of refraction of a portion of the conductive structure is determined as a function of the wave. The calculated index of refraction is used and at least one defect in the conductive structure is detected. Using this method, defects can be detected during or after the manufacture of semiconductor devices in a cost effective, reliable manner. This method is particularly useful for defects that are not detectable using typical optical scanning methods due to opaque material in semiconductor devices.

Abstract: The invention is directed to a fiber-optic sensor for measuring acoustic signals originating from a single point remote from the sensor.

Abstract: A drive line vibration sensor includes an emitter, a receiver, and a controller. The emitter and receiver are mounted in a differential manner such that drive line vibrations cause the emitter to vibrate at a different frequency than the receiver. In operation the emitter transmits a signal to the receiver such that the differential movement of the transmitter relative to the receiver produces a variation in the signal received by the receiver which is identifiable by the controller. In another embodiment, the emitter pulses the signal such that the frequency of the vibration can be determined. A recording device is preferably in communication with the controller to record the variation in the signal to provide an inexpensive diagnostic and maintenance system which can record the overall operation of a drive line under actual operational conditions.

Abstract: An apparatus and method for the remote, noncontact evaluation of structures and containers at large distances (on the order of several meters) in air is described. The invention utilizes an air-coupled, parametric acoustic array to excite resonance vibrations of elastic, fluid-filled vessels and structural members. A nonlinear mixing process in the air medium transforms highly directional, narrow beamwidth higher acoustic frequencies into lower acoustic frequencies suitable for vibrational excitation of common structures. The parametric array also has an advantage for nondestructive evaluation applications in that it is capable of producing a broader bandwidth than typical linear devices, such as speakers and ultrasonic transducers. Typical carrier frequencies are in the 200 kHz range, and the sound field 3 m from the array has been demonstrated to have a bandwidth of greater than 25 kHz at a center frequency of 15 kHz.

Abstract: An exemplary imaging apparatus includes a wave generator for generating a wave in an article; a detector for detecting a wave in the article; and a processor which: forms a matched filter based on a response of the article to a wave propagated through the article; directs the wave generator to generate a wave at a plurality of generation positions; directs the detector to detect a motion of the article at a plurality of detection positions; forms a scan data set from the detected motion of the article; multiplies the scan data set by the matched filter to produce a compensated data set; and coherently sums data points in the compensated data set to produce a focused image.

Abstract: A geophone includes an optical element capable of changing its refractive index and path length in response to acceleration of the geophone. The sensor component comprises a mass mounted on a fulcrum for rotational movement against the force of a biasing member. An optical fiber is stretched between the casing of the sensor and an extension of the mass, such that rotational movement of the mass about the fulcrum varies the tension in the fiber. Varying the tension in the fiber varies the optical path length and index of refraction of the fiber, and these variations may be detected as a seismic signal. A first set of magnets dampens the vibratory movement of the mass, and a second set of magnets reduces the frequency of the movement of the mass.

Abstract: The present invention is directed to a combined SAW sensor and a SPR sensor for evaluating an analyte, as well as a novel method for evaluating an analyte by utilizing a surface acoustic wave (SAW) sensor to determine the mass of the analyte and utilizing a surface plasmon resonance (SPR) sensor to determine the permittivity of the analyte. In accordance with one aspect of the invention, an apparatus is provided for evaluating an analyte. In one embodiment, the apparatus includes a piezoelectric substrate, a SAW sensor disposed on the substrate, and a SPR sensor disposed on the substrate in close proximity to the SAW sensor. In another embodiment, the apparatus more broadly includes a SAW sensor and a SPR sensor coupled to the surface acoustic wave sensor. In a preferred embodiment, the apparatus the SAW sensor includes two interdigital transducers and a chemically sensitive film interposed between the two interdigital transducers.

Abstract: A two- or three-component measuring accelerometer based on an operating principle entirely different from that of conventional accelerometers is realized with a simple arrangement and provided as a two- or three-component measuring seismometer. Planar optical fiber rolls (2) whose light propagation characteristics change sensitively in response to changes in the pressure applied thereto are split into more than three separate sections and disposed at the bottom of a columnar or polygonal prism-shaped load member (1). Changes in acceleration acting on the load member (1) are measured on the basis of differences between the light propagation characteristics of the split optical fiber rolls (2-1 to 2-4).

Abstract: An optical tracker system comprises an optical sensor 1 and associated signal processing circuitry 12, 24 for conditioning signals output from the sensor and rejecting signal indicative of false sensor information. A signal rejection circuit 24 comprises a guard time monostable 28 arranged to generate a guard time pulse defining a guard time when a pulse is input from the sensor 1, an output monostable 35 arranged to generate an output pulse in response to the guard time pulse, and an output suppress monostable 30 arranged to suppress the output monostable 35 when a false signal condition occurs during the guard time.

Abstract: An optical vibration sensor includes a built-in blade provided with a system for reflecting light, a system for directing light onto the reflecting system, system for collecting the light reflected by the reflecting system and a system for analyzing the intensity and/or the frequency and/or the phase of the reflected light. The blade forms an integral part of an appropriately cut block.

Abstract: A process is disclosed for determining the vibration characteristics of a body by modal analysis. The body is made to vibrate at different frequencies and optical interference images of the body are recorded for the different frequencies. The interference images are analyzed on the basis of a mathematical/physical model, in view of the vibration characteristics at predetermined points, and the thus obtained information about the vibration characteristics of said points is subjected to a modal analysis.

Abstract: The present invention discloses a method and system for laser ultrasonic imaging an object. In the present invention, a synthetic aperture focusing technique (SAFT) is used to generate a high resolution subsurface images of the object. In addition, the present invention filters low frequency components from detected laser ultrasound waveform data to further enhance resolution, SNR, and contrast. Geometric knowledge permits the present invention to generate images of objects having a complex and arbitrary-shape.

Abstract: In a method and an apparatus for exciting acoustic waves, the surface of an object is irradiated with coherent parallel energy beams and coherent focusing energy beams which have different frequencies in such a manner that they overlap each other to generate interference fringes (concentric circles) propagating from outside to the inside at propagation speed which is higher than a specific acoustic speed of the object. The acoustic waves are excited in accordance with distortion distribution generated in the surface of the object attributable to the photo-thermal effect of the interference fringes, the acoustic waves being focused to a small region in the object, the position of which is determined by the specific acoustic speed of the object and the propagation speed of the interference fringes.

Abstract: Position of a diffusely scattering surface is detected by interfering backscattered light from respective input beams which illuminate a common spot. Through polarization of the input beams and appropriate filtering, backscattered light is isolated from specularly reflected light and interfered to form a fringe pattern on a detector. The position sensor has particular applicability as a push pin sensor in a hard disk servo system.

Abstract: An apparatus for aiming an ultrasonic beam to nondestructively test an object has an ultrasonic transducer for generating the ultrasonic beam having a beam axis and impinging the ultrasonic beam upon the object. The apparatus includes a laser aiming apparatus for directing at least one laser beam having a laser sight line substantially coaxial with the ultrasonic beam axis.The laser aiming apparatus, in one embodiment of the invention, includes a cross-hair apparatus for generating a laser beam cross-hair having a center along the laser sight line. Another embodiment of the present invention provides an ultrasonic mirror apparatus for bending the ultrasonic beam and which has a mirror made of a material that is substantially transparent to the laser beam.

Abstract: A passive blade vibration monitor sensor for determining an arrival time of a blade of a combustion turbine during operation, the sensor includes an optical lens which receives infrared radiation generated by the blade of the turbine and generates a sensor signal from the received infrared radiation, the sensor signal indicating an arrival time of the blade of the combustion turbine. Target material having an emissivity lower than the emissivity of the blade may be placed on the blade to enhance sensor sensitivity especially in shrouded blade environments.

Abstract: This invention is directed to a method of remotely measuring the viscosity of molten materials such as melt glass, melt alloys, etc. during processing of the material.

Abstract: Samples such as thin polymeric films are analyzed using optically induced phonons by excitation of the sample using radiation preferably absorbed by the sample and probe radiation, preferably not absorbed by the sample, that is diffracted from the surface of the sample. The pulse width of the probe is preferably on the order of the detectable diffraction signal so that the phonon decay from each excitation pulse can be detected and analyzed. The technique is applicable to various samples by inducing a ripple morphology on the sample surface and detection of light diffracted substantially from surface ripple.

Abstract: A system for non-destructively measuring an object and controlling industrial processes in response to the measurement is disclosed in which an impulse laser generates a plurality of sound waves over timed increments in an object. A polarizing interferometer is used to measure surface movement of the object caused by the sound waves and sensed by phase shifts in the signal beam. A photon multiplier senses the phase shift and develops an electrical signal. A signal conditioning arrangement modifies the electrical signals to generate an average signal correlated to the sound waves which in turn is correlated to a physical or metallurgical property of the object, such as temperature, which property may then be used to control the process. External, random vibrations of the workpiece are utilized to develop discernible signals which can be sensed in the interferometer by only one photon multiplier.

Abstract: A method and apparatus for generating and detecting ultrasound on a workpiece utilizing a long pulse laser. A modulated pulsed laser beam is directed at the workpiece. The pulse duration is defined to be the time of propagation of ultrasound from a generation location to a flaw or discontinuity to be detected within the workpiece and then to a detection location, or, the time of propagation of ultrasound directly from the generation location to the detection location. A second pulsed laser beam, having a pulse duration longer than the ultrasonic propagation time, is also directed at the workpiece. After receiving phase modulated light from second pulsed laser beam reflected or scattered by the workpiece, phase modulated light is demodulated to obtain a demodulation signal representative of the ultrasonic motion at the surface of the workpiece. The demodulation signal is then electronically processed.