ULTRASONIC IMAGE PICKING-UP AND LITHOGRAPHY SYSTEM

摘要

PROBLEM TO BE SOLVED: To discriminate between a higher harmonic component contained in the response signal of biological tissue and a higher harmonic component contained in the response signal of a contrast medium to extract both components. SOLUTION: A transmission part 20 transmits a plurality (M; with the provi so that natureal number of >=2) of sine wave like ultrasonic wave signals of at least one cycle in the same direction as ultrasonic beam so as to leave a time interval and the ultrasonic signal of each time is transmitted while first and second waveforms asymmetric with respect to a phase axis or polarity are alternately changed over. Each of the first and second waveforms has a plurality of frequency components and at least the amplitude of a first half wave is set larger than the amplitude of the succeeding waveform. A receiving part 30 subjects the response signals of plural (M) times of ultrasonic waves to phasing processing to be added or subtracted to attenuate the response signal of biological tissue.