Fast sound field characterization of beamforming capable capacitive micromachined ultrasonic transducer (CMUT) arrays by refracto-vibrometry

We introduce a time-optimized setup based on refracto-vibrometry for the purpose of scanning the sound field of capacitive micromachined ultrasonic transducer (CMUT) arrays primarily for the qualification of their beamforming capability. In comparison to commonly used microphones on a traversing stage the proposed method is substantially faster and consumes only a few minutes of time for a complete two-dimensional sound field containing about 100.000 scan points.