Acoustic examination, material characterization and imaging of the internal structure of a body by measurement of the time-of-flight of acoustic energy therethrough

The method of measuring the spatial distribution of acoustic velocities within a plane of interest through a body, comprising the steps of:

• (a) transmitting pulses of acoustic energy through said body from different directions along a plurality of paths lying substantially in said plane;
• (b) receiving the acoustic energy pulses thus transmitted through the body;
• (c) measuring the time-of-flight of said pulses;
• and
• (d) mathematically reconstructing the acoustic velocity at a plurality of points within the plane of interest in the body.

A method of characterizing the material within a body by measuring acoustic velocities and attenuation coefficients within the body, comprising the steps of:

• (a) transmitting pulses of acoustic energy from a plurality of different directions through the body substantially along a plane of interest;
• (b) receiving the acoustic energy thus transmitted through the body;
• (c) measuring the time of flight of said pulses;
• (d) measuring the amplitude of the received pulses;
• (e) reconstructing the distribution of acoustic velocities at a plurality of points within the plane of interest;
• and
• (f) reconstructing the attenuation coefficients at a plurality of points within said plane of interest.

A method of imaging the internal structure of a body along a plane of interest therethrough, comprising the steps of:

• (a) scanning the body through the plane of interest by transmitting ultrasonic pulses through the body from a plurality of different directions along the plane, and receiving the pulses thus transmitted through the body;
• (b) measuring the time-of-flight of said pulses from transmission to reception;
• (c) mathematically reconstructing the acoustic velocity at a plurality of picture elements through the plane of interest;
• and
• (d) visually displaying the velocity data to form a sectional image of the body along said plane.

Apparatus for examining the internal structure of a body comprising:

• (a) means for transmitting acoustic energy through said body from a plurality of different directions;
• (b) means for measuring the time-of-flight of the acoustic energy through the body;
• and
• (c) means for mathematically reconstructing the acoustic velocity at a plurality of points within said body.

Apparatus for measuring the spatial distribution of acoustic velocities within a plane of interest through a body, comprising:

• (a) means for transmitting pulses of acoustic energy through said body from different directions along a plurality of paths lying substantially in said plane;
• (b) means positioned in relation to said transmitting means for receiving acoustic energy pulses transmitted through the body;
• (c) measurement means operatively connected to said receiving means, for producing signals indicative of the time-of-flight of said acoustic energy pulses;
• and
• (d) calculator means connected to receive said signals, for reconstructing the acoustic velocity at a plurality of points within the plane of interest in the body.

Apparatus for examining the internal structure of a body along a plane of interest therethrough, comprising:

• (a) an ultrasonic source adapted upon energization for emitting ultrasonic energy;
• (b) means for receiving ultrasonic energy;
• (c) mounting means for positioning said source and said receiving means on opposite sides of a zone for accommodating a body to be examined;
• (d) means connected to said mounting means for angular adjustment thereof;
• (e) detector means connected to said receiver means, for producing time-of-flight measurement signals for received pulses;
• (f) control means operatively connected for repetitively energizing said source and for time referencing said detector for successive time-of-flight measurements, and operatively connected to said angular adjustment means for angularly repositioning said mounting means between successive time-of-flight measurements;
• and
• (g) computation means connected to said detector to receive said time-of-flight signals, for mathematically reconstructing the spatial distribution of acoustic velocities at a plurality of points within the plane of interest.

Apparatus for examining the internal structure of a body along a plane of interest therethrough, comprising:

• (a) means defining a closed boundary array of ultrasonic transducers having an aperture for receiving a body to be examined;
• (b) an ultrasonic frequency generator for selective excitation of said transducers;
• (c) detection means for measurement of time-of-flight of received pulses;
• (d) switching means for selectively connecting individual transducers of said array to said generator and other transducers to said detection means, so as to provide transmission of energy pulses through the body;
• (e) control means connected to said switching means for stepping through a sequence of different transducer connections to obtain a plurality of time-of-flight measurements;
• and
• (f) computation means connected to said detection means to receive said time-of-flight measurements, and operable to mathematically reconstruct the spatial distribution of acoustic velocities at a plurality of points within the plane of interest.