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 poymericly 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: Spiral, sparse spiral, substantially spiral or substantially sparse spiral transducer arrays comprising capacitive micromachined ultrasonic transducer elements disposed on a silicon substrate, and ultrasound imaging systems employing same. The transducer elements are respectively coupled to a plurality of amplifiers. Imager electronics are coupled to each of the amplifiers and drives the transducer elements and/or generates an output of the spiral transducer array. The amplifiers may be located in the silicon substrate containing the transducer elements, or on a separate substrate that is interconnected to the substrate containing the transducer elements using bumps, for example. Electrical interconnection to the transducer elements may readily be achieved without interfering with the acoustic output of the transducer elements.

Abstract: A method for improving the coupling of an acoustic window or lens to a RFI shield by modifying the surface of the shield to promote adhesion. The surface of the shield can be chemically modified with an epoxy and/or mechanically modified by creating an unsmooth top surface.

Abstract: A method and system for coherent ultrasound imaging of induced, distributed source, bulk acoustic emissions. First, bulk acoustic emissions are induced from distributed sources within an object from a single transmit event of non-acoustic energy. Next, coherent signals are stored for each of a selected number of transducer elements of a transducer array receiving the induced bulk acoustic emissions. The stored coherent signals can then be focused to form an ultrasound image. Additionally, motion of an imaged object can be detected using induced, distributed source, bulk acoustic emissions.

Abstract: A method and structure for improving the coupling of an acoustic window or lens to a RFI shield by modifying the surface of the shield to promote adhesion. The surface of the shield can be chemically modified with an epoxy and/or mechanically modified by creating an unsmooth top surface.

Abstract: There is provided a broadband transducer array for use in an acoustic imaging system having a plurality of transducer elements disposed on a preformed support. The support has a non-planar top surface on which are disposed a plurality of elevationally curved transducer elements. Kerfs separate each transducer element from one another. The depth of the kerf with reference to the non-planar top surface of the support may be uniform or non-uniform.

Abstract: According to the present invention, an ultrasonic probe for use with a remote ultrasonic imaging system is provided, having a multielement transducer with an upper surface and a lower surface. An ultrasonically attenuative backing material adjoins the lower surface of the multielement transducer. The attenuative backing material is disposed within a container. A circular track is mounted to the container, and a flexible assembly and a carrier band are attached to the container. The carrier band may be operable to rotate the multielement transducer about an axis defined by the circular track. Alternatively, the circular track may be operable to rotate the multielement transducer. Additionally, a method of forming near real-time images of an object in a plane that is oblique to the axis of rotation of the multielement transducer is provided.

Abstract: According to the present invention, an ultrasonic imaging system having a remote ultrasound console and a probe connected thereto for inspecting an interior region of a body is provided. The ultrasonic imaging system includes a scanhead housing disposed at a distal end of the probe. A transducer is mounted upon a support structure within the scanhead housing and is electrically connected to the ultrasonic imaging system. The present invention also includes a magnetic position sensor located within the scanhead housing and coupled to the ultrasonic imaging system. The magnetic sensor may be attached to the support structure. In addition, the present invention may include a piezomotor mounted within an ultrasound probe, the piezomotor being mechanically coupled to an acoustic device within the probe.

Abstract: According to the present invention, an ultrasonic probe for use with a remote ultrasonic imaging system is provided, having a multielement transducer with an upper surface and a lower surface. An ultrasonically attenuative backing material adjoins the lower surface of the multielement transducer. The attenuative backing material is disposed within a container. A circular track is mounted to the container, and a flexible assembly and a carrier band are attached to the container. The carrier band may be operable to rotate the multielement transducer about an axis defined by the circular track. Alternatively, the circular track may be operable to rotate the multielement transducer. Additionally, a method of forming near real-time images of an object in a plane that is oblique to the axis of rotation of the multielement transducer is provided.

Abstract: A transducer has tapered piezoelectric layer sides in order to reduce the sidelobe levels. In addition, matching layers disposed on the piezoelectric layer may similarly be tapered to further increase performance. Alternative to tapering the piezoelectric layer, the top electrode and/or the matching layers may be reduced in size relative to the piezoelectric layer such that they generate a wave which destructively interferes with the undesirable lateral wave. There are also described methods for manufacturing a reduced sidelobe transducer.

Abstract: An ultrasound transducer comprising an array of individual piezoelectric transducer elements mounted upon an improved backing comprising rigid polymeric or polymer-coated particles fused into a macroscopically rigid structure having remnant tortuous permeability to provide high acoustic attenuation and to permit fluid passage into the backing structure during fabrication.

Abstract: A method is described for making a piezoelectric composite for building an acoustic transducer from two or more pieces of piezoelectric material. Each piece of material is cut to form slots or trenches having a uniform pitch spacing and material portions of uniform width such that the material portions of one piece may be received within the slots or trenches of the other. The pieces are then interdigitated and joined to make the piezoelectric composite.

Abstract: Methods for characterizing acoustic transducers and using a characterized acoustic transducer for measuring cement impedance of a cased well are disclosed. The method for characterizing the acoustic transducer generally comprises: arranging the acoustic transducer a predetermined distance from a calibration target of known thickness; transmitting a pulse from the acoustic transducer through a known medium and toward the calibration target and measuring a return signal received therefrom; and fitting, via minimization, a return signal calculation generated by a model of the return signal which has a limited number of parameters, to the received return signal to determine a value for at least one of the parameters and thereby characterize the transducer. The preferred parameters for characterization are the transducer radius and stand-off, such that the transducer may be characterized as having an effective stand-off and an effective radius.