• Gia-Thinh Bui Department of Electrical and Mechanical Engineering, Hai Phong University, Vietnam
Keywords: CMUT, three-dimensional, non-contact control, proximity detection


In this study, a membrane of polymer-based capacitive micro-machined ultrasonic transducer (CMUT) was designed for 3D proximity detection. The diameter of the membrane is 600 µm and the thickness is 5 µm. The overall size of a quadrant transducer array is 3mm × 3mm, and a four-quadrant sensor is used in 2 × 2 forms. The relationship between the membrane size and the resonance frequency are also analyzed using the ANSYS software. The design, fabrication, and characteristic measurement of the CMUT were completed, and the feasibility of the three-dimensional (3D) proximity detection was verified by using a 2×2 transducer array. The CMUT detected a vertical distance of 10 mm, the vertical and horizontal position accuracy can reach 0.4 mm and 0.6 mm. In the future, the CMUT can be used for non-contact control screens, 3D mice, and other products, are use in hospitals, exhibition halls, public places, etc.


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How to Cite
Gia-Thinh Bui. (2023). POLYMER-BASED CAPACITIVE MICRO-MACHINED ULTRASONIC TRANSDUCER FOR 3D PROXIMITY DETECTION. UTEHY Journal of Science and Technology, 37, 7-12. Retrieved from http://jst.utehy.edu.vn/index.php/jst/article/view/580