A dual frequency ultrasonic probe for medical applications

Author

Saitoh, S. ; Izumi, M. ; Mine, Y.

Author_Institution

Mater. & Devices Labs. Res. & Dev. Center, Toshiba Corp., Kawasaki, Japan

Volume

42

Issue

2

fYear

1995

fDate

3/1/1995 12:00:00 AM

Firstpage

294

Lastpage

300

Abstract

A dual frequency probe using a multilayer ceramic is proposed for simultaneously obtaining a high resolution B mode and a high sensitivity Doppler mode image. This ceramic consists of two layers in which the poling directions are opposite and the individual thicknesses are different. It is possible to control the values of relative electromechanical coupling factors in the fundamental and the second harmonic by changing the thickness ratio. A thickness ratio of 1:0.7 was decided from computer simulation based on the Mason´s model. A sufficient resolution has been shown from the fact that the intima of the carotid artery could be distinguished by an actually fabricated probe with dual frequencies of 3.75 and 7.5 MHz. Also, the sensitivity of this probe in the Doppler mode at 5 cm depth from the surface has been improved as much as 5 dB over that of a conventional one.<>

Keywords

biomedical equipment; biomedical ultrasonics; probes; ultrasonic devices; 3.75 MHz; 5 cm; 7.5 MHz; Mason´s model; carotid artery intima; dual frequency ultrasonic probe; high resolution B mode images; high sensitivity Doppler mode images; medical diagnostic imaging; medical instrumentation; multilayer ceramic; poling directions; relative electromechanical coupling factors; second harmonic; thickness ratio; Bioceramics; Biomedical equipment; Carotid arteries; Computer simulation; Frequency; Image resolution; Medical services; Nonhomogeneous media; Probes; Thickness control;

fLanguage

English

Journal_Title

Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on

Publisher

ieee

ISSN

0885-3010

Type

jour

DOI

10.1109/58.365242

Filename

365242