Non-Contact Surface Temperature Sensing Based on a Single Bimorph pMUTs Array

This paper reports the non-contact surface temperature measurements using a single piezoelectric micromachined ultrasonic transducers (pMUTs) array based on time-of-flight (ToF) for the first time. Compared with the state-of-art technologies, four distinctive advancements have been achieved: (1) non-contact surface temperature sensing via pMUTs by the pulse-echo mode to detect the changes in ToF; (2) independence on surface material properties, e.g. emissivity; (3) integration with an ultrasonic analog frontend for both transmitting and receiving; and (4) recorded sensitivity of 143 ns/°C in ToF. As such, the proposed sensing scheme and results could open up a new class of non-contact temperature sensing in various media (air, liquid, tissue ...) for industrial and biomedical applications.