Abstract: Methods, devices, and systems for detecting one or more discontinuities of a structure may include a laser emitter configured to generate and direct an ultrasonic signal into a structure and a receiver comprising an optical microphone. The optical microphone may comprise an array of optical microphones configured in a complementary manner to the emitter.

Abstract: Transducers and methods for converting acoustic signals into electrical signals. A device (100) includes an interferometer (106) including two mirrors (108) adapted for reflecting electromagnetic radiation (112) coupled into a space (110) between the mirrors (108). The acoustic signal (102) is to be coupled into the space (110) for influencing the electromagnetic radiation (112) in accordance with this acoustic signal. An electromagnetic radiation detector (112) is adapted for detecting the influenced electromagnetic radiation (112) and for converting the detected influenced electromagnetic radiation (112) into the electric signal (104) being indicative for the acoustic signal (102). An operation point stabilization unit stabilizes an operation point of the device (100).

Abstract: A device comprising measurement (7) and reference (3) interferometers is disclosed. Each interferometer is configured to receive light from the same light source (1) and to emit light to respective detectors (6) and has a respective operating point. The measurement interferometer (7) is configured to respond to variations in a physical parameter by varying the intensity of light emitted, whereas the reference interferometer (3) is configured to be unresponsive to variations in the physical parameter. The device further comprises a signal processor for generating a differential output signal depending on respective output signals generated by the detectors (6).

Abstract: A device (100) for converting an acoustic signal (102) into an electric signal (104), wherein the device (100) includes an interferometer (106) including two mirrors (108) adapted for reflecting electromagnetic radiation (112) coupled into a space (110) between the mirrors (108). The acoustic signal (102) is to be coupled into the space (110) for influencing the electromagnetic radiation (112) in accordance with this acoustic signal. An electromagnetic radiation detector (112) is adapted for detecting the influenced electromagnetic radiation (112) and for converting the detected influenced electromagnetic radiation (112) into the electric signal (104) being indicative for the acoustic signal (102). An operation point stabilization unit stabilizes an operation point of the device (100).

Abstract: An acoustoelectric transducer comprising a laser source A and a light receiver H, wherein a soundfield S is provided by which the propagation velocity of the laser beam may be modulated according to the sound pressure while it traverses the soundfield S.