Multilayer 2D ultrasonic Imaging Array Transducers for Three Dimensional Undersea Imaging Applications

Under separate Navy funding, MSI has developed a low cost injection molding process for piezocomposite fabrication that has made these innovative materials available for the first time in manufacturing quantities. MSI has used this technology to make large area 1-3 type piezoelectric ceramic/polymer composite actuator panels for use in undersea sensing, actuation, and acoustic imaging. In one program, MSI is adapting its piezocomposite designs to fabricate transducers that couple efficiently to air or water. In another, the company has adapted its injection molding process to form extremely fine transducer arrays, suitable for high frequency applications. In this program, MSI plans to utilize these piezoelectric composite manufacturing capabilities to form low electrical impedance 2D arrays for use in 3D ultrasonic imaging. By multilayering the PZT ceramic elements, the electrical impedance of the small 2D PZT pillars can be drastically reduced, resulting in enhanced signal-to-noise ratio compared to monolithic array elements. The key innovation is the method used to form the multilayer array. In Phase I, MSI will demonstrate that multilayer PZT 2D transducer array structures can be made cost-effectively, and will develop a simple lab- scale demonstration array with interconnects. In Phase II a working array will be assembled and tested in an underwater 3D imaging demonstration relevant to Navy acoustic imaging needs.