Method and device for the characterization of tissue by reflection of ultrasonic pulses a wide band of frequencies, the transposition of the spectrum of the frequency of the echo in a range of audible and diagnosis by listening

摘要

The device consists of circuits (1-2-3) for transmitting high frequency ultrasonic carrier pulses to the tissue, circuits (1-4) for receiving the echoes and converting them into high frequency electrical signals, and circuits (5-6-10-11-14) for memorizing the said electrical signals with a sampling frequency that is high enough for the high frequency information they contain to be correctly recorded. Circuits (11 to 19) read the memorized information at a rate lower than the sampling frequency so that the high frequency spectrum is transposed to the audible frequency range. Circuits (7-8-9) then convert the transposed spectrum into an audible signal. …IMAGE…