Ultrasonic transducer element.

摘要

The invention relates to a focus-type ultrasonic transducer element including a polymer piezoelectric film (3) operating as a transmitter and/or receiver of ultrasonic waves. The polymer piezoelectric film (3) accompanied with front (4) and rear (2) electrodes is divided into sections defined by wave planes emanated from an imaginary focal point or line (F) located in front of the polymer piezoelectric film with a phase difference of lambda /2, lambda being the wavelength of the ultrasonic waves within an acoustic transmission medium located between the film surface and the imaginary focal point of line, and the sections are arranged so that ultrasonic waves emanated from adjacent sections have no phase difference at the imaginary focal point or line.