Method and apparatus for ultrasonic examination

• US 4,167,180 A
• Filed: 03/23/1978
• Issued: 09/11/1979
• Est. Priority Date: 05/01/1975
• Status: Expired due to Term

• Current Assignee: Commonwealth of Australia C/-The Department of Health
• Original Assignee: Commonwealth of Australia C/-The Department of Health
• Inventors: Kossoff, George
• Primary Examiner(s): Michell, Robert W.
• Assistant Examiner(s): Jaworski, Francis J.
• Application Number:
  US05/889,255
• Time in Patent Office: 537 Days
• Field of Search: 128/2 V, 128/2.05 Z, 73/620-626, 73/619, 340/1 R, 340/5 H, 340/5 MP
• US Class Current: 600/445
• CPC Class Codes: A61B 8/0825 for diagnosis of the breast, e.g. mammography
• CPC Class Codes: A61B 8/406 using means for diagnosing suspended breasts
• CPC Class Codes: A61B 8/4209 by using holders, e.g. positioning frames
• CPC Class Codes: A61B 8/44 Constructional features of the ultrasonic, sonic or infrasonic diagnostic device
• CPC Class Codes: G01N 29/06 Visualisation of the interior, e.g. acoustic microscopy medical or veterinary diagnosis using sonic waves A61B8/00; representation of acoustic wave distribution G01H3/125, G01H9/002; short-range imaging systems using reflection of acoustic waves G01S15/8906
• CPC Class Codes: G01N 29/0609 Display arrangements, e.g. colour displays indicating or recording in connection with measuring in general G01D
• CPC Class Codes: G01N 29/223 Supports, positioning or alignment in fixed situation mounting transducers per se G10K11/004
• CPC Class Codes: G01N 29/262 by electronic orientation or focusing, e.g. with phased arrays phased arrays per se G10K11/34
• CPC Class Codes: G01S 15/8938 using transducers mounted for mechanical movement in two dimensions
• CPC Class Codes: Y10S 128/915 Ultrasound mammography

Abstract

Apparatus for the pulse-echo ultrasonic examination of an object comprisedf transducer means for transmitting pulses of ultrasonic energy and receiving reflected echoes of said pulses immersed in a coupling medium contained within a housing, the pulses being transmitted and echoes received through an aperture in the housing which may be covered with a flexible coupling membrane.

Claims

1. A method of ultrasonic examination of an object which comprises directing pulses of ultrasonic energy from a plurality of transducers along a plurality of beam axes through a liquid coupling bath and into said object, each beam axis being associated with one of said plurality of transducers, and receiving echoes of said pulses reflected along said beam axes by acoustic impedance discontinuities in said object, said directing step including:

directing said pulses into the object from said plurality of transducers at spaced positions relative to each other and to said object;

steering said beam axes to a plurality of angular directions in a single plane; and

directing said pulses sequentially along each of said beam axes in each of said angular positions at a rate sufficiently fast, compared to the rate of movement of the transducer beams, that each transducer beam axis moves only a small distance between successive activations of said one of said plurality of transducers, said sequential activation along said transducer beam axes comprising sequential activation along a non-adjacent beam axis substantially simultaneously with the receipt of echoes of a previous pulse.

2. An apparatus for the ultrasonic examination of an object comprising:

a liquid coupling bath;

a plurality of transducers for directing pulses of ultrasonic energy along a beam axis through said liquid coupling bath and into said object and receiving echoes of said pulses reflected along said beam axis by acoustic impedance discontinuities in said object, said transducers being spatially positioned relative to each other and to the said object;

means for steering the beam axis of each of said transducers to a plurality of angular directions in a single plane; and

means for sequentially activating each of said transducers to direct a pulse of ultrasonic energy along a beam axis into the object and to receive echoes reflected along said beam axis in each of said angular directions at a rate sufficiently fast, compared to the rate of movement of the transducer beam, that each transducer beam axis moves only a small distance between successive activations of each respective transducer, said means for sequentially activating each of said transducers comprising means for activating non-adjacent transducers to direct a pulse of ultrasonic energy along a beam axis into the object substantially simultaneously with the receipt of echoes resulting from activation of the previously activated transducer.