Ultrasonic echographic apparatus with a controllable phase coherence.

摘要

Ultrasonic echograph comprising at the emitting end and/or at the receiving end circuits for imposing delays on the emitted and/or received signals, according to a law of random or pseudo-random delays. At the emitting end as at the receiving end, this law is superposed with that of focusing and angulation of the signals. At the emitting end, the said law is obtained for example by varying the instants of triggering of the generators of transducer excitation signals. At the receiving end, the means provided are either parallel random delay lines, or conditional inversion circuits. These electronic means permitting breakage of the coherence of the ultrasonic waves at the emitting end, at the receiving end, or at both ends simultaneously, can just as well be proposed in an analog or digital version.
<??>Application: echographs for medical or industrial use.
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