Finite amplitude distortion-based inhomogeneous pulse echo ultrasonic imaging

Abstract

A method and system for imaging a sample. The method includes the steps of generating an ultrasonic signal, directing the signal into a sample, which signal is distorted and contains a first order and higher order component signals at first and higher frequencies respectively. The received distorted signal is processed, and an image is formed, and then displayed, from one of the higher order component signals of the received distorted signal.

1 - 22 . (canceled)  
   
   
       23 . An ultrasound tissue harmonic imaging method, comprising the steps of: 
 providing a biological tissue sample;    using a transmit-receive unit to generate a transmit ultrasonic signal at a fundamental frequency, and to direct the ultrasound signal into and along a propagation path in the sample, wherein the tissue distorts the transmit ultrasonic signal along the propagation path and thereby produces a distorted ultrasonic signal including harmonic components at second and higher order harmonic frequencies to the fundamental frequency, and further wherein the sample also reflects and scatters the distorted ultrasonic signal including said harmonic components;    using the transmit-receive unit to receive the harmonic components of the reflected or scattered distorted ultrasonic signal;    high pass filtering the received harmonic components to produce a resultant signal;    digitizing the resultant signal; and    processing said digitized resultant signal to produce an ultrasound image of the biological tissue sample from one or more of the received harmonic components.    
   
   
       24 . A method according to  claim 23 , wherein said transmit-receive unit is a phased array transmit-receive unit.  
   
   
       25 . A method according to  claim 23 , wherein said transmit signal has a focal point, and the transmit-receive unit includes electrical circuitry to move said focal point.  
   
   
       26 . An ultrasound tissue harmonic imaging system for imaging a biological tissue sample, the system comprising: 
 a transmit-receive unit to generate a transmit ultrasonic signal at a fundamental frequency, and to direct the ultrasound signal into and along a propagation path in the sample, wherein the tissue distorts the transmit ultrasonic signal along the propagation path and thereby produces a distorted ultrasonic signal including harmonic components at second and higher order harmonic frequencies to the fundamental frequency, and further wherein the sample also reflects and scatters the distorted ultrasonic signal including said harmonic components; said transmit-receive unit also adapted to receive the harmonic components of the reflected or scattered distorted ultrasonic signal;    a high pass filter to filter the received harmonic components to produce a resultant signal;    an analog-to digital converter to digitize the resultant signal; and    a processor to process said digitized resultant signal to produce an ultrasound image of the biological tissue sample from one or more of the received harmonic components.    
   
   
       27 . A system according to  claim 26 , wherein said transmit-receive unit is a phased array transmit-receive unit.  
   
   
       28 . A system according to  claim 26 , wherein said transmit signal has a focal point, and the transmit-receive unit includes electrical circuitry to move said focal point.