Development and Performance Evaluation of PDMS Acoustic Lens for Enhanced Performance in CMUT Systems

This paper presents a comprehensive study on the design and fabrication of a convex acoustic lens for capacitive micromachined ultrasonic transducers (CMUTs) using polydimethylsiloxane (PDMS). The primary objective is to enhance ultrasound focusing capabilities, which is critical for improving the performance of CMUT-based systems. The proposed convex lens configuration was evaluated against lens less and flat matching layer configurations, demonstrating enhanced acoustic performance. The convex lens achieved a receiving sensitivity of -229.74 dB, a transmitting sensitivity of 164.43 dB, and a 36.5% bandwidth. Additionally, it produced a narrower main lobe width of 7.49 degrees, indicating improved directional control of the ultrasonic waves. These results highlight the significant advantages of using a convex PDMS lens to enhance ultrasonic transducer performance, particularly in terms of sensitivity and focusing precision. The optimized design holds great potential for a wide range of applications, including medical diagnostics, where accurate imaging and focused ultrasound are paramount, industrial inspection, which requires precise flaw detection, and environmental monitoring, where sensitive and accurate detection of sound waves is critical.