Abstract: Methods for fabricating high frequency ultrasound transducers are disclosed. The methods include fabricating an acoustic lens layer with a curved center section and two flat side sections. The curved section includes a center portion with a midpoint and an edge. The midpoint has a first thickness, and the edge has a second thickness. The center portion is fabricated so that an average of the first and second thicknesses is approximately equal to an odd multiple of a quarter-wavelength of the center frequency of the ultrasound transducer. The methods can also include bonding the lens layer to a matching layer that is operationally coupled to a transducer layer. The matching layer can include an epoxy layer and another layer. Bonding the lens layer includes bonding the other layer to the lens layer using the epoxy layer such that the other layer is positioned between the epoxy layer and the transducer layer.

Abstract: A high frequency ultrasound array having a number of transducer elements that are formed in sheet of piezoelectric material. A frame having a coefficient of thermal expansion that is similar to that of the piezoelectric material surrounds the piezoelectric material and is separated from the piezoelectric material by a filling material. Kerf cuts that define the individual elements in the sheet of piezoelectric material extend across a full width of the sheet. In some embodiments, sub-dice kerf cuts that divide a single transducer element into two or more sub-elements also extend all the way across the width of the sheet. A lens positioned in front of the transducer elements can have a radius machined therein to focus ultrasound signals.

Abstract: A dual frequency transducer array includes one or more low frequency transducer arrays and a high frequency transducer array. Unfocused ultrasound such as plane waves are transmitted by the one or more low frequency transducer arrays in a number of different directions into an imaging region of the high frequency transducer array. High frequency echo signals produced by excited contrast agent in the imaging region are received by the high frequency transducer array to produce a contrast agent image. In another embodiment, the high frequency transducer produces unfocused ultrasound to excite the contrast agent in the imaging region and the low frequency transducer(s) receives low frequency echo signals from the excited contrast agent. A tissue image is created from echo signals received by the high or low frequency transducer. Echo data from the tissue image and the contrast agent image are combined to produce a combined tissue/contrast agent image.

Abstract: A hydrophone used for measuring acoustic energy from a high frequency ultrasound transducer, or a method of manufacturing the membrane hydrophone. The membrane assembly is supported by the frame and comprises a piezoelectric. The hydrophone also includes an electrode pattern formed within the piezoelectric to define an active area. In addition, the hydrophone includes a built in-situ coaxial layer connected to the active area.

Abstract: A dual frequency ultrasound transducer includes a high frequency ultrasound array and a low frequency transducer positioned behind or proximal to the high frequency ultrasound array. In one embodiment, a dampening material is positioned between a rear surface of the high frequency array and the a front surface of the low frequency array. The dampening preferably is high absorbing of signals at the frequency of the high frequency array but passes signals at the frequency of the low frequency transducer with little attenuation. In additional, or alternatively, the low frequency can angled with respect to the plane of the high frequency transducer to reduce inter-stack multipath reflections. Beamforming delays compensate for the differences in physical distances between the elements of the low frequency transducer and the plane of the high frequency transducer.

Abstract: An ultrasound transducer has an array of transducer elements that are electrically coupled to electrical conductors. In one embodiment, the conductors are included in a flex circuit and engage a conductive surface formed on a number of outwardly extending ribs on a frame that holds the ultrasound array. In one embodiment, the flex circuit includes an alignment feature that engages a corresponding registration feature on the frame so that the traces on the flex circuit align with the ribs on the frame.

Abstract: The disclosed technology features methods for the manufacture of electrical components such as ultrasound transducers. In particular, the disclosed technology provides methods of patterning electrodes, e.g. in the connection of an ultrasound transducer to an electrical circuit; methods of depositing metal on surfaces; and methods of making integrated matching layers for an ultrasound transducer. The disclosed technology also features ultrasound transducers produced by the methods described herein.

Abstract: High frequency ultrasound transducers configured for use with high frequency ultrasound diagnostic imaging systems are disclosed herein. In one embodiment, an ultrasound transducer includes a concave lens having an average thickness in a center portion that that is substantially equal to an odd multiple a ¼-wavelength of the center frequency of the ultrasound transducer.

Abstract: Disclosed is a medical device that includes a phased array ultrasound transducer. The transducer includes a number of transducer elements that are electrically coupled to corresponding electrical conductors. In one embodiment, the conductors are included in a flex circuit and engage corresponding transducer elements though a conductive surface formed on outwardly extending ribs of a frame that holds the ultrasound array. In one embodiment, the phased array is forward facing in the medical device and has an element pitch of 0.75 lambda or less and more preferably 0.6 lambda or less. In one embodiment, the transducer is rotatable over an angle of +/?90 degrees to provide a 360 degree view of tissue surrounding the distal end of the device.

Abstract: The disclosed technology features methods for the manufacture of electrical components such as ultrasound transducers. In particular, the disclosed technology provides methods of patterning electrodes, e.g. in the connection of an ultrasound transducer to an electrical circuit; methods of depositing metal on surfaces; and methods of making integrated matching layers for an ultrasound transducer. The disclosed technology also features ultrasound transducers produced by the methods described herein.

Abstract: Methods of manufacturing high frequency ultrasound transducers configured for use with high frequency ultrasound diagnostic imaging systems are disclosed herein. In one embodiment, methods of manufacturing an ultrasound transducer includes providing a concave lens having an average thickness in a center portion that that is substantially equal to an odd multiple of a ¼-wavelength of the center frequency of the ultrasound transducer.

Abstract: A dual frequency ultrasound transducer includes a high frequency ultrasound array and a low frequency transducer positioned behind or proximal to the high frequency ultrasound array. In one embodiment, a dampening material is positioned between a rear surface of the high frequency array and the a front surface of the low frequency array. The dampening preferably is high absorbing of signals at the frequency of the high frequency array but passes signals at the frequency of the low frequency transducer with little attenuation. In additional, or alternatively, the low frequency can angled with respect to the plane of the high frequency transducer to reduce inter-stack multipath reflections. Beamforming delays compensate for the differences in physical distances between the elements of the low frequency transducer and the plane of the high frequency transducer.

Abstract: A dual frequency ultrasound transducer includes a high frequency ultrasound array and a low frequency transducer positioned behind or proximal to the high frequency ultrasound array. In one embodiment, a dampening material is positioned between a rear surface of the high frequency array and the a front surface of the low frequency array. The dampening preferably is high absorbing of signals at the frequency of the high frequency array but passes signals at the frequency of the low frequency transducer with little attenuation. In additional, or alternatively, the low frequency can angled with respect to the plane of the high frequency transducer to reduce inter-stack multipath reflections. Beamforming delays compensate for the differences in physical distances between the elements of the low frequency transducer and the plane of the high frequency transducer.

Abstract: An ultrasound transducer has an array of transducer elements that are electrically coupled to electrical conductors. In one embodiment, the conductors are included in a flex circuit and engage a conductive surface formed on a number of outwardly extending ribs on a frame that holds the ultrasound array. In one embodiment, the flex circuit includes an alignment feature that engages a corresponding registration feature on the frame so that the traces on the flex circuit align with the ribs on the frame.

Abstract: A hydrophone used for measuring acoustic energy from a high frequency ultrasound transducer, or a method of manufacturing the membrane hydrophone. The membrane assembly is supported by the frame and comprises a piezoelectric. The hydrophone also includes an electrode pattern formed within the piezoelectric to define an active area. In addition, the hydrophone includes a built in-situ coaxial layer connected to the active area.

Abstract: An ultrasound transducer has an array of transducer elements that are electrically coupled to electrical conductors. In one embodiment, the conductors are included in a flex circuit and engage a conductive surface formed on a number of outwardly extending ribs on a frame that holds the ultrasound array. In one embodiment, the flex circuit includes an alignment feature that engages a corresponding registration feature on the frame so that the traces on the flex circuit align with the ribs on the frame.

Abstract: In one aspect, matching layers for an ultrasonic transducer stack having a matching layer comprising a matrix material loaded with a plurality of micron-sized and nano-sized particles. In another aspect, the matrix material is loaded with a plurality of heavy and light particles. In another aspect, an ultrasound transducer stack comprises a piezoelectric layer and at least one matching layer. In one aspect, the matching layer comprises a composite material comprising a matrix material loaded with a plurality of micron-sized and nano-sized particles. In a further aspect, the composite material can also comprise a matrix material loaded with a plurality of heavy and light particles. In a further aspect, a matching layer can also comprise cyanoacrylate.

Abstract: A membrane hydrophone for analyzing high frequency ultrasound transducers has a piezoelectric membrane with electrode patterns created on the surface of the membrane. In one embodiment, the electrode patterns are doubled on each side of the membrane except for an active area of the hydrophone. In one embodiment, the electrodes are formed by removing a conductive coating on the membrane with laser pulses. The laser is set to remove the conductive coating from the piezoelectric membrane from the same side of the membrane in order to accurately align the electrodes in the active area. In one embodiment, the active area of the hydrophone has an area in a range of 900-10,000 square microns.

Abstract: High frequency ultrasound transducers configured for use with high frequency ultrasound diagnostic imaging systems are disclosed herein. In one embodiment, an ultrasound transducer includes a concave lens having an average thickness in a center portion that that is substantially equal to an odd multiple a ¼-wavelength of the center frequency of the ultrasound transducer.

Abstract: A high frequency ultrasound array having a number of transducer elements that are formed in sheet of piezoelectric material. A frame having a coefficient of thermal expansion that is similar to that of the piezoelectric material surrounds the piezoelectric material and is separated from the piezoelectric material by a filling material. Kerf cuts that define the individual elements in the sheet of piezoelectric material extend across a full width of the sheet. In some embodiments, sub-dice kerf cuts that divide a single transducer element into two or more sub-elements also extend all the way across the width of the sheet. A lens positioned in front of the transducer elements can have a radius machined therein to focus ultrasound signals.