Performance enhancement of a piezoelectric linear array transducer by half-concave geometric design

Cheung, K.F., Zhou, D., Lam, K.H. , Chen, Y. and Dai, J.Y. (2011) Performance enhancement of a piezoelectric linear array transducer by half-concave geometric design. Sensors and Actuators A: Physical, 172(2), pp. 511-515. (doi: 10.1016/j.sna.2011.09.035)

Abstract

A geometric design for array elements of a piezoelectric linear array transducer is proposed and evaluated. The design concept is based on the half-concave geometry, in which the radiating surface is concave while the other surface remains plane. A ∼1.8 MHz piezoelectric linear array transducer with half-concave elements has been designed, fabricated and evaluated. A dicing method was developed to shape the concave surfaces of the piezo elements and matching layers. By comparing the transducer performance, a traditional linear array transducer with similar dimension has been fabricated. It was found that the half-concave array transducer has significantly broader −6 dB bandwidth (96%), higher effective electromechanical coupling coefficient (0.62), and lower insertion loss (−21 dB) compared to those (76%, 0.55, and −25 dB, respectively) of the plane array transducer. The enhanced coupling coefficient and bandwidth are caused by the broaden resonance of the elements, which is induced by the continuously varying thickness in the designed geometry. The increased sensitivity is mainly attributed to the focused radiating surface.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Lam, Dr Koko
• Authors: Cheung, K.F., Zhou, D., Lam, K.H., Chen, Y., and Dai, J.Y.
• College/School: College of Science and Engineering > School of Engineering > Systems Power and Energy
• Journal Name: Sensors and Actuators A: Physical
• Publisher: Elsevier
• ISSN: 0924-4247
• ISSN (Online): 1873-3069