Abstract: A system and method for detecting ultrasonic surface displacements at a remote target are disclosed, one embodiment of the system comprising: a first laser to generate a first laser beam. The first laser beam produces ultrasonic surface displacements on a surface of the remote target. A second laser generates a second laser beam operable to detect the ultrasonic surface displacements on the surface of the remote target and to provide a reference beam to an interferometer. The second laser beam is split, at a beam-splitter, into a pump beam and a probe beam. The pump beam is amplified by a first amplifier and the probe beam is amplified by a second amplifier. The pump beam is then provided to the interferometer as a reference beam and the probe beam is directed to the target to detect the ultrasonic surface displacements. The first and second amplifiers can be controlled independently of one another to control their respective laser beam's power.

Abstract: The invention is directed to a wave characteristic adjusting device used to compensate for a wave characteristic distortion caused by the scanning motion of a probe beam of a two-wave mixing interferometer. The invention is also directed to an apparatus and method for using the wave characteristic adjusting device in a rapid scanning laser ultrasound testing device. In a rapid scanning laser ultrasound testing device, a laser pulse is directed at periodic points along a path across the surface of a manufactured object. The laser pulse initiates an ultrasonic signal associated with the manufactured object. An interferometer may be used to measure the initiated ultrasonic signal. The interferometer scans a probe beam along a path similar to the sonic initiating laser. A pulse of the probe beam is directed at the manufactured object in the vicinity of the initiating laser pulse while continuously scanning. As a result, the probe beam pulse may exhibit a Doppler shift.

Abstract: An interferometer includes a cavity including a pair of mirrors defining a cavity length. An input beam and a counter-propagating reference beam are directed into the cavity. The interferometer generates a feedback control signal and an ultrasound signal for optimal performance and measurement of a target, respectively.

Abstract: A laser ultrasonic measurement system includes a first and a second laser source configured to generate a first and a second laser beam, respectively. A movable mechanical link is arranged to transmit the first laser beam. The movable mechanical link is formed by a plurality of rigid sections interconnected by rotating joints. A robot is configured to support and control the movement of at least a section of the mechanical link to transmit the first laser beam to an object. An optical scanner is positioned proximate to the mechanical link. The optical scanner is configured to direct the first and second laser beams onto the object. An interferometer is optically coupled to the optical scanner. The interferometer is configured to receive reflected light from the object and in response generate an electrical signal. The first laser source is kinematically mounted in a housing assembly.

Abstract: A system and method for the analysis of composite materials. Improved techniques for the measurement of the shape and position of the composite article are provided, which include improved scanning rates using structured light.

Abstract: A compact high average power mid infrared range laser for ultrasound inspection. The laser comprises one of a Nd:YAG or Yb:YAG laser pumped by a diode at 808 nm to produce a 1 micron output beam. The 1 micron output beam is directed to an optical parametric oscillator where the beam wavelength is converted to 1.94 microns and conveyed to a mid infrared emission head. The emission head comprises one of a Ho:YAG or Ho:YLG laser optically coupled with a second optical parametric oscillator. The second optical parametric oscillator forms a generation output beam for creating ultrasonic displacements on a target. The generation output beam wavelength ranges from about 3 to about 4 microns, and can be 3.2 microns.

Abstract: A method of spectroscopic analysis of a material using a laser ultrasound system. The method includes measuring amplitude displacement of a target surface that has been excited with a generation laser. The amplitude displacements relate to the target's optical absorption properties. Amplitude displacements are generated over a range of laser wavelengths to obtain an optical absorption signature useful to identify the target material characteristics.

Abstract: A system and method for the analysis of composite materials. Laser ultrasound measurements of composite materials are correlated to the shape and position of the composite article.

Abstract: A mid infrared range laser source for ultrasound inspection that comprises a high energy laser coupled with one or more harmonic generation devices. The high energy laser may be a CO2 laser and tuned to emit laser light at a single wavelength. The harmonic generation devices convert the laser beam into the mid infrared range for optimal ultrasound inspection.

Abstract: A system and method for the analysis of composite materials. Structured light measurements are used to determine the 3-dimensional shape of an object, which is then analyzed to minimize the number of scans when performing laser ultrasound measurements.

Abstract: A method of ultrasonic testing comprising conditioning a radiation wave from a laser source by efficiently converting the radiation wave's wavelength to a mid-IR wavelength for enhanced ultrasonic testing of a composite. The method includes passing the radiation wave through a first optical frequency converter where the radiation wave is converted into a signal wave and an idler wave, where the idler wave is at a mid-IR wavelength. The method further includes directing the signal and idler waves to a second optical frequency converter where the signal wave wavelength is converted to a mid-IR wavelength which combines with the idler wave to form a generation wave. The generation wave is directed at a composite surface to be tested.

Abstract: A laser transmission system.

Abstract: A laser transmission system.

Abstract: Embodiments of the present invention relates to an improved laser for the optical detection of ultrasound. The primary task of this “first” detection laser is to illuminate the spot where a “second” laser is used to generate ultrasound in the part under test. The scattered light from the first laser is collected and analyzed with an interferometer to demodulate the surface vibrations caused by the return echoes of the ultrasound at the surface of the part. The improved detection laser (first laser) is constructed using a diode-pumped fiber laser to produce a high power single-frequency laser source.

Abstract: The invention is directed to a system and method for implementing process control for temperature of a semiconductor wafer using sonic NDE techniques. The system may, for example, generate ultrasound waves in a test object during the manufacturing process. A detector such as an interferometer may be used to detect the ultrasound waves. An interpreter or analyzer may determine the temperature of the semiconductor wafer from the waves. Then, a control system may determine and implement an appropriate control action on the process.

Abstract: An inspection system is provided to examine internal structures of a target material. This inspection system combines an ultrasonic inspection system and a thermographic inspection system. The thermographic inspection system is attached to ultrasonic inspection and modified to enable thermographic inspection of target materials at distances compatible with laser ultrasonic inspection. Quantitative information is obtained using depth infrared (IR) imaging on the target material. The IR imaging and laser-ultrasound results are combined and projected on a 3D projection of complex shape composites. The thermographic results complement the laser-ultrasound results and yield information about the target material's internal structure that is more complete and more reliable, especially when the target materials are thin composite parts.

Abstract: The present invention provides a compact optical probe assembly that measures ultrasound in materials. The probe uses angle-terminated optical fiber to direct illumination laser light at the surface of a remote target. Ultrasonic displacements at the surface scatter the illumination laser light. Angle-terminated optical fibers collect phase modulated light and direct the phase modulated light to an optical processor to produce a signal representative of the ultrasonic surface displacements. The probe may also incorporate angle-terminated optical fibers to direct generation laser light to the surface of a remote target to generate ultrasonic surface displacements. Optional shared beam forming element(s) may optically act on the illumination laser and collected phase modulated light.

Abstract: The invention is directed to a system and method for implementing process control for tubing thickness using sonic NDE techniques. The system may, for example, generate ultrasound waves in a test object during the manufacturing process. A detector such as an interferometer may be used to detect the ultrasound waves. An interpreter or analyzer may determine the tubing or sheet thickness from the waves. Then, a control system may determine and implement an appropriate control action on the process.

Abstract: The invention is directed to a system and method for implementing process control for paper elasticity and thickness using sonic NDE techniques. The system may, for example, generate ultrasound waves in a test object during the manufacturing process. A detector such as an interferometer may be used to detect the ultrasound waves. An interpreter or analyzer may determine the thickness and/or elastic properties of paper from the waves. Then, a control system may determine and implement an appropriate control action on the process.

Abstract: An ultrasonic non-destructive evaluation (NDE) system operable to inspect target materials is provided. This ultrasonic NDE system includes an articulated robot, an ultrasound inspection head, a processing module, and a control module. The ultrasound inspection head couples to or mounts on the articulated robot. The ultrasound inspection head is operable to deliver a generation laser beam, a detection laser beam, and collect phase modulated light scattered by the target materials. The processing module processes the phase modulated light and produces information about the internal structure of the target materials. The control module directs the articulated robot to position the ultrasound inspection head according to a pre-determined scan plan.