APPARATUS FOR THE INVESTIGATION OF MEDIA BY ULTRASONIC ECHOGRAPHY

摘要

The combined modality device comprises an ultrasound transducer (10) which is suitable for transmission as well as reception and which is connected to a transmitter stage (20) as well as to a receiver stage (30). The transducer (10) has a bandwidth which at least equals approximately one octave. The transmitter stage (20) comprises a generator for generating activation signals for the transducer (10) with a frequency fo near the lower limit of said bandwidth, the spectrum of these activation signals excluding the frequency f1=2fo. The receiver stage (30) comprises a B-scan channel and also a B/A processing channel (200) which itself includes a bandpass filter (210) which is centered around said frequency f1, an envelope detector (220, 230), a comparison circuit (240), a differentiation circuit (250) and a display device (260) whereby measured results in both modalities may be displayed.