Development in High Frequency Ultrasonic Imaging and Transducers

There has been intense interest recently in ultrasonic imaging in the frequency range from 20 MHz and beyond in biomedicine. High frequency ultrasound has applications in dermatology, ophthalmology and intravascular imaging because of its superior resolution. The performance of ultrasonic imaging systems especially at high frequencies depends critically upon the transducers/arrays, the design of which in turn is determined to a large degree by the materials and fabrication methodology of the piezoelectric element and supporting structures. Recent developments in these areas are discussed in this paper.