| 摘要 |
<p>Disclosed is an ultrasonic lens configuration permitting the production of an acoustic field from low frequency ultrasound waves with predictable regions of energy concentration. The lens comprises at least three adjacent convex surface contours. Each surface contour corresponds to an arc of an ellipse. The first surface contour is within the center of the lens and is flanked by two adjacent contours. The flanking contours correspond to arcs from two symmetrical ellipses having semi-latus rectums at least equal to the semi-latus rectum of the ellipse to which the first, central, contour corresponds. The contours of the lens are arranged such that the flanking contours extend past the first contour by positioning the contours so that if the ellipses to which they correspond were drawn the ellipses of the flanking contours directly adjacent to the first contour would have their centers aligned on a plane parallel to and not below the major or minor axis of the ellipse of the first contour.</p> |
