Abstract: Multiple layer elements for a transducer array are provided. Each element comprises two or more layers of transducer material. Various of the elements include one or more of: (1) multiple-layer, multiple-dimensional arrays where the layers are polymericly bonded together and electrically connected through asperity contact, (2) multiple layer array of elements where air or gas separates at least two elements, (3) an even number of layers where each layer is electrically connected through asperity contact, (4) multiple-layers where each layer comprises transducer material and electrodes in a substantially same configuration, and (5) electrically isolating electrodes on layers by kerfing or cutting after bonding the layers together.

Abstract: An ultrasound transducer assembly is disclosed having a housing, a transducer array mounted in the housing and an electronics assembly mounted in the housing, the electronics assembly including one or more sub-assemblies having heat generating components disposed thereon. The electronics sub-assemblies further include thermal conducting features which conduct heat generated by the heat generating components out of the electronics assembly where it can be further removed by other thermal management techniques. These other thermal management techniques may include techniques utilized to cool the transducer array.

Abstract: Ultrasound transducer temperatures are measured in response to a temperature dependent property of the ultrasound transducer. The temperature is measured without addition of new electronics or hardware retrofits of the transducer. By implementing software and/or hardware on the ultrasound system rather than the transducer, the temperature is measured in order to provide a level of fault protection. The upgraded or new ultrasound system uses either old or new transducers while still providing temperature measurement. For example, the temperature of the lens or window is measured as a function of changes in attenuation or acoustic velocity. The receive beamformer already implemented on many ultrasound systems is used to measure a temperature dependent property of the lens or window. As another example, the dielectric constant or capacitance of one or more transducer elements is measured using additional hardware in the ultrasound system.

Abstract: A multi-dimensional transducer array has pitch along one dimension less than the pitch along a second dimension. The multi-dimensional transducer array with the same or different pitch is manufactured from a plurality of modules. Each of the modules are separately diced and then aligned and combined. Elements of a transducer array are used for isolating a transmit channel from a receive channel. Separate signal lines or traces are provided individually for each element on opposite sides of each element. A transmit channel may connect to one electrode on an element, and the receive channel may connect to an opposite electrode on the element. A multi-dimensional array is provided for time division multiplex processing. A probe houses the multi-dimensional array and a multiplexer.

Abstract: Multiple layer elements for a transducer array are provided. Each element comprises two or more layers of transducer material. Various of the elements are manufactured by one or more of: (1) stacking to form a multiple-layer, multiple-dimensional array where the layers are polymericly bonded and electrically connected through asperity contact, (2) using air or gas to separate at least two elements, (3) stacking an even number of layers where each layer is electrically connected through asperity contact, (4) using multiple-layers where each layer comprises transducer material and electrodes in a substantially same configuration, and (5) electrically isolating electrodes on layers by kerfing or cutting after bonding the layers together.

Abstract: Transducer systems for mode dependent tuning and associated methods are provided. One or more tuning circuits are provided within a transducer probe. The tuning circuit is switchably connected to the transducer. By connecting or disconnecting the tuning circuit, the tuning for the transducer element is varied. Selective tuning of a medical ultrasound transducer allows different tuning for different modes of operation. For example, the frequency response of the transducer is varied between different modes of imaging, such as B-mode and flow-mode imaging. Higher frequency signals are used for higher resolution B-mode imaging, but a stronger response at lower frequency is desired for better penetration during flow-mode imaging and Doppler modes. Mode is used in a general sense, such as associated with an imaging mode as well as a type of operation (e.g. transmit mode versus receive mode operation).

Abstract: An ultrasound transducer assembly is disclosed having a housing, a transducer array mounted in the housing and an electronics assembly mounted in the housing, the electronics assembly including one or more sub-assemblies having heat generating components disposed thereon. The electronics sub-assemblies further include thermal conducting features which conduct heat generated by the heat generating components out of the electronics assembly where it can be further removed by other thermal management techniques. These other thermal management techniques may include techniques utilized to cool the transducer array.

Abstract: Ultrasound transducer temperatures are measured in response to a temperature dependent property of the ultrasound transducer. The temperature is measured without addition of new electronics or hardware retrofits of the transducer. By implementing software and/or hardware on the ultrasound system rather than the transducer, the temperature is measured in order to provide a level of fault protection. The upgraded or new ultrasound system uses either old or new transducers while still providing temperature measurement. For example, the temperature of the lens or window is measured as a function of changes in attenuation or acoustic velocity. The receive beamformer already implemented on many ultrasound systems is used to measure a temperature dependent property of the lens or window. As another example, the dielectric constant or capacitance of one or more transducer elements is measured using additional hardware in the ultrasound system.

Abstract: Images of the heart are formed by using multiple sets of ultrasound data. Each set of data is acquired and processed responsive to a different set of imaging parameters. The imaging parameter sets differ in at least one parameter, such as array position, temporal frequency response or transmit focal depth, so that the images formed using these data sets have, either laterally or axially, different spatial spectra. A set of images is formed responsive to a first imaging parameter set for a first cardiac cycle. Another set of images is formed responsive to a second imaging parameter set for a second cardiac cycle. The two sets of images are temporally aligned so that they correspond to the same set of phases of the cardiac cycle. Since the data acquisition and processing are distributed over multiple cycles of the motion, assuming regular periodic heart cycle, temporal resolution is maintained.

Abstract: Multiple layer elements for a transducer array are provided. Each element comprises two or more layers of transducer material. Various of the elements include one or more of: (1) multiple-layer, multiple-dimensional arrays where the layers are polymericly bonded and electrically connected through asperity contact, (2) multiple layer array of elements where air or gas separates at least two elements, (3) an even number of layers where each layer is electrically connected through asperity contact, (4) multiple-layers where each layer comprises transducer material and electrodes in a substantially same configuration, and (5) electrically isolating electrodes on layers by kerfing or cutting after bonding the layers together.

Abstract: Methods and systems for forming images of heart by using multiple sets of ultrasound data are described. Each set of data is acquired and processed responsive to a different set of imaging parameters. The imaging parameter sets differ in at least one parameter, such as array position, temporal frequency response or transmit focal depth, so that the images formed using these data sets have, either laterally or axially, different spatial spectra. In one of the preferred embodiments, a set of images is formed responsive to a first imaging parameter set for a first cardiac cycle. Another set of images is formed responsive to a second imaging parameter set for a second cardiac cycle. Then the two sets of images are temporally aligned so that they correspond to the same set of phases of the cardiac cycle. The temporally aligned images may also be spatially aligned and combined. This technique can improve contrast resolution and/or field of view.

Abstract: A transducer system and method for harmonic imaging is provided. At least one transducer element is provided. The transducer element comprises two or more stacked piezoelectric layers. Information from each of the layers is independently processed during one of a transmit event, a receive event, and both transmit and receive events. Information from the transducer element is provided to a filter. The filter isolates harmonic information for imaging. By providing a multi-layer transducer element with independent processing for each layer, a wide bandwidth transducer for harmonic imaging is provided. The null associated with most transducers at the second harmonic of a fundamental frequency is removed or lessened.

Abstract: Transducer arrays and methods of manufacturing the transducer arrays are provided. A multi-dimensional transducer array is provided where the element-to-element spacing or pitch along one dimension is less than the element spacing or pitch along a second dimension. For example, the element pitch along an azimuth dimension is ½ of the element pitch along an elevation dimension. The multi-dimensional transducer array with the same or different pitch is manufactured from a plurality of modules. Each of the modules are separately diced and then aligned and combined. Separate dicing allows for individual testing of modules prior to assembly as a transducer array. Elements of a transducer array are used for isolating a transmit channel from a receive channel. Rather than a sheet of electrode acting as a ground plane common to a plurality of elements, separate signal lines or traces are provided individually for each element on opposite sides of each element.

Abstract: An ultrasound transducer assembly having a housing, a transducer array mounted in the housing, and active cooling mechanism positioned adjacent to the transducer array for actively removing heat generated by the array by transport of heat energy from the affected site. The active cooling mechanism comprises a thermo-electric cooler which utilizes active thermal transport to remove heat from the transducer. The thermoelectric cooler may be used alone or in combination with a phase change material or other system to subsequently remove the heat from the thermo-electric cooler. The thermo-electric cooler is coupled with the flex-circuit layers of the transducer to efficiently remove heat generated within the component layers of the transducer.

Abstract: Multiple layer elements for a transducer array are provided. Each element comprises two or more layers of transducer material. Various of the elements include one or more of: (1) multiple-layer, multiple-dimensional arrays where the layers are electrically connected through asperity contact, (2) multiple layer array of elements where air or gas separates at least two elements, (3) an even number of layers polymerically bonded together where each layer is electrically connected through asperity contact, (4) multiple-layers where each layer comprises transducer material and electrodes in a substantially same configuration, and (5) electrically isolating electrodes on layers by kerfing or cutting after bonding the layers together.

Abstract: The use of any micro-mechanical component in an ultrasound system is disclosed. In particular, the use of micro-mechanical ultrasound transducers, micro-relays, micro-switches and inductors in the transducer probe head, in the transducer connector, coupled with the system transducer connector(s) or anywhere else in the system. In an ultrasound system, micro-mechanical components such as micro-mechanical ultrasound transducers, micro-fabricated switches, relays and inductors permit impressive size reduction, cost reduction, signal-integrity enhancement and improved operational flexibility.

Abstract: Multiple layer elements for a transducer array are provided. Each element comprises two or more layers of transducer material. Various of the elements include one or more of: (1) multiple-layer, multiple-dimensional arrays where the layers are electrically connected through asperity contact, (2) multiple layer array of elements where air or gas separates at least two elements, (3) an even number of layers where each layer is electrically connected through asperity contact, (4) multiple-layers where each layer comprises transducer material and electrodes in a substantially same configuration, and (5) electrically isolating electrodes on layers by kerfing or cutting after bonding the layers together.

Abstract: A capacitive microelectromechanical ultrasound transducer array with improved efficiency and durability is provided. Efficiency is provided by stacking CMUTs in the range dimension (i.e. away from the face of the transducer). A plurality of chambers and associated membranes are stacked along a range dimension or parallel to the direction of acoustic radiation. Because the CMUT transducer element is stacked, ultrasound is transmitted through the plurality of chambers, amplifying the response of the transducer element. Durability is increased within the transducer by filling the chamber with a nongaseous filler. A liquid, polymer, solid or plasma fills the chamber or chambers. The nongaseous filler allows movement of the membrane for transducing between acoustic and electrical energies, but prevents collapse or bottoming out of the membrane.

Abstract: Multiple layer elements for a transducer array are provided. Each element comprises two or more layers of transducer material. Various of the elements include one or more of: (1) multiple-layer, multiple-dimensional arrays where the layers are electrically connected through asperity contact, (2) multiple layer array of elements where air or gas separates at least two elements, (3) an even number of layers where each layer is electrically connected through asperity contact, (4) multiple-layers where each layer comprises transducer material and electrodes in a substantially same configuration, and (5) electrically isolating electrodes on layers by kerfing or cutting after bonding the layers together.

Abstract: Multiple layer elements for a transducer array are provided. Each element comprises two or more layers of transducer material. Various of the elements include one or more of: (1) multiple-layer, multiple-dimensional arrays where the layers are polymericly bonded and electrically connected through asperity contact, (2) multiple layer array of elements where air or gas separates at least two elements, (3) an even number of layers where each layer is electrically connected through asperity contact, (4) multiple-layers where each layer comprises transducer material and electrodes in a substantially same configuration, and (5) electrically isolating electrodes on layers by kerfing or cutting after bonding the layers together.