System and method for three-dimensional ultrasound imaging

A multi-focus acoustic lens for focusing ultrasonic pulses transmitted by a concave transducer array having transducer rows at desired locations in an object for generating multiple images of the object in an azimuthal direction, comprising:

• a body member that includes a front surface, said body member having an inner surface, the inner surface being configured and arranged so to be concave in the azimuthal direction;
• wherein the body member front surface is configured and arranged so to that a multiplicity of lens rows are provided therein, the multiplicity of lens rows forming an entire lens comprised of a center lens row, and a plurality of uncentered lens rows forming at least two outer lens rows relative to the said center lens row when said entire lens is viewed elevationally, where each of the multiplicity of lens rows has an outer surface, the outer surface being convex in the azimuthal direction;
• wherein a pair of uncentered lens rows that are symmetric in an elevation direction with respect to an azimuthal centerline of said center lens of the body member have same focal points;
• wherein each said lens row is elevationally and azimuthally aligned to cover an entire transmit/receive area of a respective individual concave transducer row to focus a beam transmitted through the entire lens in an elevational and azimuthal direction;
• wherein said inner surface of each said lens rows varies in height in a range direction relative to a lens row of the entire lens to which it is adjacent;
• wherein each said lens row has a constant curvature and a radius when viewed cross-sectionally;
• wherein the said center lens row has a smaller radius and a larger curvature in size as compared to each of the said radius and each of the said curvature of each said uncentered lens rows, so that a center portion of the said center lens row is not coincident with a center portion of an arc formed by any symmetric uncentered lens row pair;
• wherein the said lens rows have f-numbers which are essentially constant with one another;
• wherein each said lens row is sized to simultaneously deliver all components of an echo received by the entire lens to a beamformer;
• and
• a moving mechanism operably coupled to the body member for moving the body member including the entire lens to one or more radial positions with respect to the object being imaged thereby generating the multiple images in the azimuthal direction.

A multi-focus lens for focusing transmitted ultrasonic signals at desired locations in an object and for focusing returned ultrasonic signals received from the object for generating multiple images of the object in an azimuthal direction, where the ultrasonic signals are transmitted from a concave ultrasound transducer array configured to transmit ultrasonic signals through the multi-focus lens for focusing the transmitted ultrasonic signals into an object, wherein the concave ultrasound transducer array includes a plurality of curvilinear concave-shaped transducer rows, wherein each curvilinear concave-shaped transducer row, which includes at least one ultrasonic transducer element, is of the same or different dimension as the other curvilinear concave-shaped transducer rows, said multi-focus lens comprising:

• multiple lens rows forming an entire lens comprised of a center lens row and a plurality of uncentered lens rows forming at least two outer lens rows relative to the center lens row when said entire lens is viewed elevationally for focusing the ultrasonic signals in an elevation direction, wherein each lens row is configured with an inner and outer surface;
• wherein the inner surface is of a concaved curved shape in the azimuthal direction for elevationally and azimuthally aligning with a corresponding transmit/receive area of a respective transducer row for covering the corresponding transducer row and the ultrasonic transducer element;
• wherein the outer surface for each lens row is of a convex shape in the azimuthal direction for focusing the concave ultrasound transducer array in an elevational direction at desired locations into an object along a path of the transmitted ultrasonic signals;
• wherein the concave inner surface of at least one inner surface of the lens row varies in height in a range direction relative to the concave inner surface of a lens row of the entire lens to which it is adjacent;
• wherein the concave inner surfaces of the uncentered lens rows that are symmetric in the elevation direction about an azimuthal centerline of the center row of the multiple lens rows are configured and arranged so as to have same focal points;
• wherein each said lens row has a constant curvature and a radius when viewed cross-sectionally,
• wherein the said center lens row has a smaller radius and a larger curvature in size as compared to each of the said radius and each of the said curvature of each said uncentered lens row, so that a center portion of the said center lens row is not coincident with a center portion of an arc formed by any symmetric uncentered lens row pair;
• wherein the said lens rows have f-numbers which are essential constant with one another;
• wherein each said lens row is sized to simultaneously deliver all components of an echo received by the entire lens to a beamformer;
• and
• a moving mechanism operably coupled to the entire lens when the multi-focus lens is aligned with the concave ultrasound transducer array for moving the multi-focus lens and the concave ultrasound transducer array to one or more radial positions with respect to the object to be imaged thereby generating the multiple images in the azimuthal direction.

A multi-focus lens for focusing ultrasonic pulses at desired locations in an object for generating multiple images of the object in an azimuthal direction when the ultrasonic pulses are transmitted from a concave ultrasound transducer array configured to transmit ultrasonic pulses into an object, wherein the concave ultrasound transducer array includes a plurality of curvilinear concave-shaped transducer rows, wherein each curvilinear concave-shaped transducer row, which includes at least one ultrasonic transducer element, is of the same or different dimension as the other curvilinear concave-shaped transducer rows, said multi-focus compound lens comprises:

• multiple lens rows forming an entire lens comprised of a center lens row and a plurality of uncentered lens rows forming at least two outer lens rows relative to the center lens row when the entire lens is viewed elevationally for focusing ultrasonic pulses from a concave ultrasound transducer array in an elevation direction, wherein each said multiple lens row is configured with an inner surface and outer surface, wherein the inner surface is of a curvilinear concave-shape in the azimuthal direction for azimuthally aligning with a corresponding curvilinear concave-shaped transducer row for covering the transmit/receive area of the corresponding curvilinear concave-shaped transducer row and the ultrasonic transducer element associated therewith and the outer surface is of a convex elevation shape in the azimuthal direction for focusing the concave ultrasound transducer array in an elevation direction at desired locations into an object along a path of ultrasonic pulses when transmitted from a concave ultrasound transducer array in an elevation direction, wherein the inner surface of at least one lens row varies in height in a range direction relative to a lens row of the entire lens to which it is adjacent and wherein when, two or more of said uncentered multiple lens rows are symmetric in an elevation direction with respect to an azimuthal centerline of center lens row, said symmetric uncentered lens rows have the same focal points as one another;
• wherein each said lens row has a constant curvature and a radius when viewed cross-sectionally, wherein the said center lens row has a smaller radius and a larger curvature in size as compared to each of the said radius and each of the said curvature of each said uncentered lens row, so that a center portion of the said center lens row is not coincident with a center portion of an arc formed by any symmetric uncentered lens row, pair, wherein the said lens rows have f-numbers which are essentially constant with one another, and wherein each said lens row is sized to simultaneously deliver all components of an echo received by the entire lens to a beamformer;
• and
• a moving mechanism operably coupled to the entire lens when each of the multiple lens rows is azimuthally aligned with the corresponding curvilinear concave-shaped transducer row, for moving the entire lens and the concave ultrasound transducer array to one or more radial positions with respect to the object to be imaged thereby generating the multiple images in the azimuthal direction.