Patent ID: 7473225

Claim:
An ultrasonic imaging system which transmits/receives an ultrasonic wave to/from an object using an ultrasonic probe to image said object, comprising: means for discriminating and detecting a phase aberration from a phase shift of a receive signal in a form of a reflected ultrasonic wave returned from said object based upon a transmit signal in a form of an ultrasonic wave transmitted to said object, the phase aberration being due to an acoustic impedance map in said object and due to other factors; means for transmitting a transmit signal superimposed on an even harmonic wave of a fundamental wave; means for using an orthogonal component of a received second harmonic wave to correct the phase aberration due to frequency-dependent attenuation caused in the process of propagation of the ultrasonic wave; and means for obtaining an acoustic impedance of said object from a complex signal in which the phase shift is corrected.