Abstract: A technique for scanning an image field with adjacent beams of ultrasonic energy is provided in which initially transmitted beams are transmitted along beam directions at the lateral sides of the image field. Subsequent beams are alternately transmitted on either side of the initially transmitted beams and at lateral locations which converge toward the center of the image field until the full image field has been scanned. In an alternate embodiment initially transmitted beams are transmitted on one side of the center of the image field, subsequent beams diverge from the locations of the initially transmitted beams, and concluding beams laterally converge at a location on the other side of the center of the image field.

Abstract: A technique for scanning an image field with adjacent beams of ultrasonic energy is provided in which initially transmitted beams are transmitted along beam directions down the center of the image field. Subsequent beams are alternately transmitted on either side of the initially transmitted beams and at increasing lateral locations in said field with respect to the locations of the initially transmitted beams until the full image field has been scanned. In a preferred embodiment a waiting period is added to the pulse repetition interval of each transmission to allow time for multipath reflections to dissipate. The waiting periods are longer during initial transmissions in the vicinity of the center of the image field, and decline as beams are transmitted at increasing lateral locations of the field. The scanning technique provides a reduction in multipath reflection artifacts while maintaining a smoothly varying or uniform temporal disparity in the transmission times of adjacent beams.