Advantages of piezocomposites for immersion transducers
Very high sensitivity
The acoustic impedance of piezocomposite materials can be adjusted from approximately 10 to 15 MRay. This impedance, much lower than that of ceramics, is closer to that of water. This results in a better energy transfer which, combined with high electro-acoustic efficiency, gives a sensitivity that is 10 to 32dB higher than that obtained with monolithic piezoelectric ceramics.
Focusing by shaping
The shaping of the active area enables the beam to be focused without resorting to using a lens that absorbs some of the energy and only gives an approximate focus because of the phenomena of aberration.