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Title: HIGH-SPL PMUT ARRAY FOR MID-AIR HAPTIC INTERFACE
This paper presents a mid-air haptic interface device enabled by a piezoelectric micromachined ultrasonic transducer (pMUT) array achieving an unprecedentedly high transmission pressure of 2900 Pa at a 15 mm distance for the first time. The structure is based on sputtered potassium sodium niobate (K,Na)NbO3 (KNN) thin film with a high piezoelectric coefficient (𝑒𝑒31 ~ 8-10 C/m2). A prototype KNN pMUT array composed of 15Γ—15 dual-electrode circular-shape diaphragms exhibits a resonant frequency around 92.4 kHz. Testing results show a transmitting sensitivity of 120.8 Pa/cm2 per volt under only 12 Vp-p excitation at the natural focal point of 15 mm away, which is at least 3 times that of previously reported AlN pMUTs at a similar frequency. Furthermore, an instant non-contact haptic stimulation of wind-like sensation on human palms has been realized. As such, this work sheds light on a new class of pMUT array with high acoustic output pressure for human-machine interface applications, such as consumer electronics and AR/VR systems.  more » « less
Award ID(s):
2128311
PAR ID:
10435874
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
22th International Conference on Solid-State Sensors, Actuators and Microsystems-Transducers 2023
Page Range / eLocation ID:
124-127
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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