The Microflown sensor is a MEMS based transducer able to directly measure acoustic particle velocity.
Very small sized elements are created on silicon wafers under a clean room technology.
The sensing element consists of two ultra-thin wires (thinner than a strand of human hair).
The resulting resistance difference provides a broad band (20 Hz up to at least 10 kHz) linear signal with a figure-of-eight directivity that is proportional to the acoustic particle velocity.
Multiple application cases, theory and fundamentals of particle velocity sensing: List of academic publications related to particle velocity sensors: To model a tri-axial particle velocity probe's measurement of a source incident from the near field, see: The tri-axial particle velocity probe's azimuth-elevation beam pattern: A tri-axial particle velocity probe may be used to enhance speech reception in a video conferencing scenario: