Abstract: An ultrasound transducer includes an acoustic layer having a front side and an opposite back side. The acoustic layer is configured to convert electrical signals into ultrasound waves to be transmitted from the front side toward a target. The acoustic layer is configured to convert received ultrasound waves into electrical signals. A lens is connected to the front side of the acoustic layer. A heat sink is connected to the back side of the acoustic layer. A flex circuit is disposed between the acoustic layer and the heat sink. The flex circuit includes a backside matching layer incorporated into a body of the flex circuit. The backside matching layer is connected in thermal communication with the acoustic layer and the heat sink such that the backside matching layer is configured to conduct heat from the acoustic layer to the heat sink.

Abstract: An ultrasound transducer includes an array of acoustic elements, an integrated circuit, and an interposer. The interposer includes conductive elements for electrically connecting the acoustic elements to the integrated circuit. The conductive elements are electrically connected to the integrated circuit. Solder is engaged between the acoustic elements and the conductive elements of the interposer such that the conductive elements of the interposer are electrically connected to the acoustic elements through the solder.

Abstract: An ultrasound transducer includes an acoustic layer having a front side and an opposite back side. The acoustic layer is configured to convert electrical signals into ultrasound waves to be transmitted from the front side toward a target. The acoustic layer is configured to convert received ultrasound waves into electrical signals. A lens is connected to the front side of the acoustic layer. A heat sink is connected to the back side of the acoustic layer. A flex circuit is disposed between the acoustic layer and the heat sink. The flex circuit includes a backside matching layer incorporated into a body of the flex circuit. The backside matching layer is connected in thermal communication with the acoustic layer and the heat sink such that the backside matching layer is configured to conduct heat from the acoustic layer to the heat sink.

Abstract: An ultrasound transducer includes an array of acoustic elements, an integrated circuit, and an interposer. The interposer includes conductive elements for electrically connecting the acoustic elements to the integrated circuit. The conductive elements are electrically connected to the integrated circuit. Solder is engaged between the acoustic elements and the conductive elements of the interposer such that the conductive elements of the interposer are electrically connected to the acoustic elements through the solder.

Abstract: Ultrasound transducers and methods of making ultrasound transducers with improved thermal characteristics are provided. An ultrasound transducer can include: a backing, a piezoelectric element attached to the backing, a first matching layer attached to the piezoelectric element, and a second matching layer attached to the first matching layer. The first matching layer can comprise metal and can have a thermal conductivity of about greater than 30 W/mK. The second matching layer can have a thermal conductivity of about 0.5-300 W/mK. The first matching layer can have an acoustic impedance of about 10-20 MRayl, and the second matching layer can have a lower acoustic impedance. The first matching layer can be thicker than the second matching layer. The ultrasound transducer can include a lens and a matching layer disposed between the piezoelectric element and the lens can be configured to conduct heat from the piezoelectric element to the backing.

Abstract: An acoustical stack for use within an ultrasound transducer that has a center frequency has a poled piezoelectric material layer and at least one impedance matching layer. The poled piezoelectric material layer has top and bottom sides and is formed of poled piezoelectric material that has a first acoustic impedance. The poled piezoelectric material layer has a first thickness and the acoustical stack has an output electrical impedance based on the first thickness. The impedance matching layers are configured to be attached to the top and bottom sides of the poled piezoelectric material layer and have second or third thicknesses. The impedance matching layers are formed of one or more materials that have an acoustic impedance substantially similar to the first acoustic impedance. The poled piezoelectric layer and impedance matching layers form an acoustic resonance thickness. The center frequency of the transducer is based on the acoustic resonance thickness.

Abstract: Ultrasound transducers and methods of making ultrasound transducers with improved thermal characteristics are provided. An ultrasound transducer can include: a backing, a piezoelectric element attached to the backing, a first matching layer attached to the piezoelectric element, and a second matching layer attached to the first matching layer. The first matching layer can comprise metal and can have a thermal conductivity of about greater than 30 W/mK. The second matching layer can have a thermal conductivity of about 0.5-300 W/mK. The first matching layer can have an acoustic impedance of about 10-20 MRayl, and the second matching layer can have a lower acoustic impedance. The first matching layer can be thicker than the second matching layer. The ultrasound transducer can include a lens and a matching layer disposed between the piezoelectric element and the lens can be configured to conduct heat from the piezoelectric element to the backing.

Abstract: The invention uses a transducer and ultrasound system to form and direct ultrasound beams through the blood stream that will detect the Doppler shift in frequency between the beams and the return echo off the blood. The transducer can be secured onto the surface of the patient's skin with a transducer housing holder. A 1-D transducer, subject to an optimized angle with respect to the blood vessel, will generate and direct ultrasound beams electronically through a blood vessel below the skin and analyze the received echo, searching for the maximum signal amplitude of the Doppler frequency shift from the blood. Furthermore, the device continuously controls the direction of the ultrasound beams to achieve maximum return signal amplitude. Then, the condition and trend of the blood flow is recorded and displayed continuously over the desired diagnostic interval the device is in use.

Abstract: An acoustical stack for use within an ultrasound transducer that has a center frequency has a poled piezoelectric material layer and at least one impedance matching layer. The poled piezoelectric material layer has top and bottom sides and is formed of poled piezoelectric material that has a first acoustic impedance. The poled piezoelectric material layer has a first thickness and the acoustical stack has an output electrical impedance based on the first thickness. The impedance matching layers are configured to be attached to the top and bottom sides of the poled piezoelectric material layer and have second or third thicknesses. The impedance matching layers are formed of one or more materials that have an acoustic impedance substantially similar to the first acoustic impedance. The poled piezoelectric layer and impedance matching layers form an acoustic resonance thickness. The center frequency of the transducer is based on the acoustic resonance thickness.

Abstract: A compound flexible circuit for electrically connecting a transducer array and a cable includes a first end configured to be coupled to the transducer array and a plurality of sections. Each section has a pitch and at least one of the plurality of sections has a variable pitch. The compound flexible circuit also includes a second end configured to be coupled to the cable. Various sections and/or portions of the variable pitch section may be removed to provide a pitch appropriate for the particular transducer array.

Abstract: A two-dimensional ultrasonic transducer for forming images. The transducer has a plurality of transducer elements for producing ultrasonic bursts in a predetermined manner, and receiving reflected ultrasound from the subject under examination due to the ultrasonic bursts. The plurality of transducer elements are arranged in an array into columns and rows, the columns of the transducer elements arranged in a scanning plane for scanning the subject under examination in order to form a two-dimensional profile of the subject, and the rows of the transducer elements having groups of symmetrically arranged transducer elements being oriented in a elevational plane. Each of the groups of symmetrically arranged transducer elements are mechanically arranged to have a focus at specified locations distant from the transducer which is within the subject under examination.

Abstract: A two-dimensional ultrasonic transducer for forming images. The transducer has a plurality of transducer elements for producing ultrasonic bursts in a predetermined manner, and receiving reflected ultrasound from the subject under examination due to the ultrasonic bursts. The plurality of transducer elements are arranged in an array into columns and rows, the columns of the transducer elements arranged in a scanning plane for scanning the subject under examination in order to form a two-dimensional profile of the subject, and the rows of the transducer elements having groups of symmetrically arranged transducer elements being oriented in a elevational plane. Each of the groups of symmetrically arranged transducer elements are mechanically arranged to have a focus at specified locations distant from the transducer which is within the subject under examination.