Electronic sector scanning for ultrasonic diagnosis

The mechanical B-scan used in medical diagnosis has the main disadvantage that it does not provide instantaneous and continuous pictures as the A-scan does in the one-dimensional case. In this paper is described the development of an electronic sector scanning equipment especially for medical purposes. By means of a 21-element array sound pulses can be transmitted in every direction within a sector of 90°. This sector can be scanned at a repetition rate of about 30 scans/s.