Ultrasonic diagnosis apparatus

摘要

In an ultrasonic diagnosis apparatus, a first transmission signal including both of two fundamentals of frequencies f0 and 2f0 is transmitted, and then a second transmission signal having a polarity reverse that of the first transmission signal is transmitted. A receiving beam processor 22 generates a signal in which the echoes of the two transmission signals are added, and a signal in which the echoes are subtracted. The fundamental components are canceled out by addition and a secondary harmonic component A2 generated by the non-linear interaction remains in the sum signal. In the subtraction signal, the fundamental component remains while the secondary harmonic component is canceled out by subtraction. The fundamental component AII of the frequency 2f0 is extracted from the subtraction signal, and a ratio (A2/AII) is calculated by a divider 44. A differentiating process is then executed by an HPF 46 to obtain the evaluation value reflecting the non-linear parameter at each depth of the body. <IMAGE>