| 摘要 |
A device for the three-dimensional focusing of an ultrasonic beam, comprising: a phased array (100) has a cylindrical shape with a generatrix X'X, and which comprises MxN elementary transducers which are arranged in a curved matrix consisting off M rows extending parallel to X'X and N curved columns extending perpendicularly to said rows. A circuit (200) forms focusing planes Pj which extend through X'X, which circuit is formed by: a multiplexer (201) which selects, for each column i, from the MxN signals received by the array (100), the mo signals SjkI supplied by the elementary transducers whose row number is j+k, where K=0, 1, . . . , mo-1, where mo is a given number respresenting the aperture width of the ultrasonic beam, and which also forms the sum Sjki of the signals Sjki and Sjki, mo-k-1 supplied by the elementary transducers which are symmetrically positioned with respect to the center of the aperture, and N identical focusing circuits (202i) which apply, for each column i, a phase-resetting delay tau k to the signals Sjki and which form the sum Sji of the signals Sjki thus reset in phase. An angulation circuit (300) applies for j given, a phase rule to the N signals Sji prior to their summing, which rule defines a focusing direction D in the focusing plane Pj.
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