Capacitive micromachined ultrasonic transducer (CMUT) based micro viscosity sensor

Abstract A novel CMUT based micro viscosity sensor is presented, in which the pulse-echo ultrasound signal generated by CMUT is used as information carrier. The mechanical performance of CMUT will be changed by the viscosity of surrounding fluid medium due to the damping effect, therefore also affecting the generated ultrasound signal under the same driven condition. Through detecting this pulse-echo signal in time domain followed by performing Fourier transform, the frequency response of CMUT as well as the desired viscosity information has been successfully obtained.

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