| 摘要 |
In this method, an ultrasonic head is used which exhibits a multiplicity of adjacently located ultrasonic transducer elements (2). During the reception along a straight-line scanning line (Z1), different numbers of the ultrasonic transducer elements (2) are successively activated and thus adjusted for reception from different depth ranges ( DELTA t1, DELTA t2, DELTA t3). The aperture (A1, A2, A3) is increased step by step. The centroid of the aperture travels in the scanning direction over the ultrasonic transducer elements, one corner point remaining fixed. During the travelling, the directional characteristic of the respective active aperture (A1, A2, A3) is set in such a manner that a zig-zag-shaped scanning curve (Z'1) is obtained which largely approximates the straight-line scanning line (Z1). During the scanning of the greatest scanning depth of the object, all ultrasonic transducer elements (21 to 2N) are activated in this method. The device for carrying out the method contains for each element (2) a channel which comprises a depth compensation amplifier (10), a controlled switching device (12) and a delay device (16, 18), the outputs of these channels being connected to a summing element (22). <IMAGE>
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