Inline Transmitter/Receiver System Using Pb(Zn_1/3Nb_2/3)O₃–PbTiO₃ Single Crystal and Poly(vinylidene fluoride) for Harmonic Pulse Compression Imaging

Abstract

An inline transmitter/receiver system for intravascular ultrasound for realizing fine imaging with high resolution and high signal-to-noise ratio (SNR) is newly proposed. This system can be used for tissue harmonic imaging using pulse compression. In this system, a Pb(Zn1/3Nb2/3)O3–PbTiO3 (PZN–PT) layer is applied to the transmitter with consideration of efficient transmission, and a poly(vinylidene fluoride) (PVDF) film is used as the receiver because of its wide bandwidth, which is suitable for receiving harmonic components in echo signals. An inline structure, in which the beam axis of a transmitter coincides with that of a receiver, is required to regard the high directivity of the harmonic components as important. In this system, since coded pulses are transmitted from a PZN–PT layer through a PVDF film, which is placed on the transmission side of the PZN–PT layer, a transmitted pulse is mixed with the received echo signal. To avoid such mixing, another PVDF film is placed on the reverse side of the PZN–PT layer to cancel the transmitted pulse. Through experiments, we investigate the effectiveness of the proposed invention, and confirm the feasibility of the proposed system.