A method includes transmitting a focused ultrasound wave into a medium to form (i) an ultrasound intensity well within the medium that exhibits a first range of acoustic pressure and (ii) a surrounding region of the medium that surrounds the ultrasound intensity well and exhibits a second range of acoustic pressure that exceeds the first range of acoustic pressure. The method further includes confining an object within the ultrasound intensity well. Additionally, an acoustic lens is configured to be acoustically coupled to an acoustic transducer. The acoustic lens has a varying longitudinal thickness that increases proportionally with respect to increasing azimuth angle of the acoustic lens. Another acoustic lens is configured to be acoustically coupled to an acoustic that increases proportionally with respect to increasing azimuth angle of the segment.

A method includes transmitting a focused ultrasound wave into a medium to form (i) an ultrasound intensity well within the medium that exhibits a first range of acoustic pressure and (ii) a surrounding region of the medium that surrounds the ultrasound intensity well and exhibits a second range of acoustic pressure that exceeds the first range of acoustic pressure. The method further includes confining an object within the ultrasound intensity well. Additionally, an acoustic lens is configured to be acoustically coupled to an acoustic transducer. The acoustic lens has a varying longitudinal thickness that increases proportionally with respect to increasing azimuth angle of the acoustic lens. Another acoustic lens is configured to be acoustically coupled to an acoustic that increases proportionally with respect to increasing azimuth angle of the segment.

An acoustic module with a transducer and a solid waveguide. The transducer and waveguide may be curved to focus the acoustic energy along a focal line. The transducer, the top surface of the waveguide and the bottom surface of the waveguide may extend along coaxial curves. The waveguide may include a recess closely receiving the transducer. The waveguide may include an integral skirt that provides a thermal mass. The acoustic module may include a space to accommodate thermal management options. For example, the acoustic module may include a heatsink, an active ventilation system and/or a phase change material. The ultrasound device may include a controller configured to perform a uniformity scan sweep during supply of operating power to the transducer. The uniformity scan sweep can extend through a frequency range that includes the operating point of the acoustic module and does not exceed an acceptable efficiency loss.

An acoustic module with a transducer and a solid waveguide. The transducer and waveguide may be curved to focus the acoustic energy along a focal line. The transducer, the top surface of the waveguide and the bottom surface of the waveguide may extend along coaxial curves. The waveguide may include a recess closely receiving the transducer. The waveguide may include an integral skirt that provides a thermal mass. The acoustic module may include a space to accommodate thermal management options. For example, the acoustic module may include a heatsink, an active ventilation system and/or a phase change material. The ultrasound device may include a controller configured to perform a uniformity scan sweep during supply of operating power to the transducer. The uniformity scan sweep can extend through a frequency range that includes the operating point of the acoustic module and does not exceed an acceptable efficiency loss.

A curved phononic waveguide. In some embodiments, the curved phononic waveguide includes a sheet including a plurality of standard reflectors and a plurality of divergent reflectors. Each of the standard reflectors is associated with a respective grid point of a grid defined by a plurality of intersecting lines, each grid point being a respective intersection of two of a plurality of intersecting lines, the grid being locally periodic to within 5%, and having a local grid spacing. Each of the standard reflectors has a center separated from the respective grid point of the standard reflector by at most 1% of the grid spacing. The divergent reflectors define a waveguide among the standard reflectors, each of the divergent reflectors being an absent reflector or a reflector that is smaller than one of the standard reflectors.

Among other things, piezoelectric materials and methods of their manufacture are described; particularly methods of forming regions of varying crystal structure within a relaxor piezoelectric substrate. Such methods may including heating the piezoelectric substrate above the transition temperature and below the Curie temperature such that a first phase transition occurs to a first crystal structure; rapidly cooling the piezoelectric substrate below the transition temperature at a cooling rate that is sufficiently high for the first crystal structure to persist; and applying an electric field through one or more selected regions of the piezoelectric substrate, such that within the one or more selected regions, a second phase transition occurs and results in a second crystal structure.

Among other things, piezoelectric materials and methods of their manufacture are described; particularly methods of forming regions of varying crystal structure within a relaxor piezoelectric substrate. Such methods may including heating the piezoelectric substrate above the transition temperature and below the Curie temperature such that a first phase transition occurs to a first crystal structure; rapidly cooling the piezoelectric substrate below the transition temperature at a cooling rate that is sufficiently high for the first crystal structure to persist; and applying an electric field through one or more selected regions of the piezoelectric substrate, such that within the one or more selected regions, a second phase transition occurs and results in a second crystal structure.

A hybrid sensor assembly is configured to be mounted on a vehicle to sense structure borne and airborne noises generated as the vehicle travels over the roads. The sensor assembly includes a housing having a circuit board mounted therein, an accelerometer mounted on the circuit board, a microphone mounted on the circuit board, an acoustic port through the housing and in communication with the microphone, and an acoustic fabric attached to the housing over the port. An acoustic shield covers the acoustic port and substantially deters the entry of fluid and debris into the acoustic port.

A back side of a diamond or other substrate is thinned using plasma etches and a mask situated away from the back side by a spacer having a thickness between 50 μm and 250 μm. Typically, a combined RIE/ICP etch is used to thin the substrate from 20-40 μm to less than 1 μm. For applications in which color centers are implanted or otherwise situated on a front side of the diamond substrate, after thinning, a soft graded etch is applied to reduce color center linewidth, particularly for nitrogen vacancy (NV) color centers.

The acoustic waveguide has a flexible metal rod with a cylindrical waveguide rigidly attached to each end of the same through a conical acoustic concentrator. One cylindrical waveguide is capable of being attached to an electroacoustic transducer and the other cylindrical waveguide is capable of being attached to an acoustic oscillation receiver. The structure provides for the enhanced functional capabilities of the acoustic waveguide by utilizing it in devices operating under conditions of high temperature, radiation, strong electromagnetic interferences and other negative factors.