An acoustic standing wave is utilized to separate components from a multi-component fluid, such as animal cells from fluid-cell mixture, in a fluid flow scheme with an acoustophoresis device. For example, the flow scheme and device allows for trapping of falling cells as the cells coalesce, agglomerate, and the weight of the agglomerated mass overcomes the drag and ultrasonic standing wave forces in the device.

A vibration device that includes a first elastic plate having a first end portion and a second end portion, and a first surface and a second surface facing each other and connecting the first and second end portions. A second elastic plate is laminated to the second end portion of the first elastic plate, and a piezoelectric vibration element is provided on at least one of the first surface and the second surface of the first elastic plate. On a portion where the first elastic plate and the second elastic plate are laminated, a first bonding portion and a second bonding portion that bond the first elastic plate and the second elastic plate to each other are provided. The second bonding portion is located closer to the first end portion than the first bonding portion.

An ultrasonic transducer and an ultrasonic probe including the same are provided. The ultrasonic transducer includes a piezoelectric layer configured to convert an electric signal and an ultrasound into each other, and a dematching layer having a uniform thickness, the dematching layer being arranged on a partial region of the piezoelectric layer and configured to reflect the second ultrasound wave that is incident on the dematching layer.

Separation of particles or droplets from a host fluid may be achieved using a transducer and/or reflector that is a thin, non-planar structure. The thin non-planar structure improves operation of an acoustic standing wave generated by an acoustic transducer. The structure may operate as a pressure release boundary and may be constructed as plastic film.

Acoustophoretic devices and methods for separating biological cells (particularly T-cells) from other fluids/materials using multi-dimensional acoustic standing waves are disclosed. The devices include an inlet, at least two outlets, and a flow chamber having an ultrasonic transducer-reflector pair. Specifically, T cells, B cells, or NK cells can be separated from other blood components. A dual-pass acoustophoretic system including two acoustophoretic devices arranged in series and fluidly connected to one another is also illustrated. Means for pre-chilling the mixture prior to separation in the devices or system can be used to improve retention, concentration, and clarification and to prevent outgassing.

Rotational intravascular ultrasound (IVUS) imaging devices, systems, and methods are provided. Some embodiments are directed to transducer mounting configurations that enable polymer piezoelectric micro-machined ultrasonic transducers (PMUTs) to be used with a Doppler color flow rotational IVUS imaging system. In one embodiment, a rotational intravascular ultrasound (IVUS) device includes: a flexible elongate body; a piezoelectric micromachined ultrasound transducer (PMUT) coupled to a distal portion of the flexible elongate body; and an application-specific integrated circuit (ASIC) coupled to the distal portion of the flexible elongate body. The ASIC is electrically coupled to the PMUT and includes a pulser, an amplifier, a protection circuit, and timing and control circuitry for coordinating operation of the pulser, amplifier, and protection circuit. The PMUT transducer is mounted with a tilt angle such that the IVUS catheter can be used to collect Doppler ultrasound blood flow data in conjunction with the IVUS imaging.

Apparatus for controlling algae and bio-organisms in bodies of fluids, such as water. The algae control system includes a power unit and a transducer unit that includes a sonic head that radiates in multiple directions. The power unit connects to various power sources, including a mains supply connection, a solar panel array, and/or a battery. The power unit is electrically connected to the transducer unit. The sonic head includes a driver and a transducer subassembly. The driver excites the transducer subassembly to emit ultrasonic waves at various frequencies in the water surrounding the sonic head. Emissions at a high density of frequencies are enabled by the transducers. The frequencies include the critical structural resonant frequency for each microorganism to be controlled. The power unit and driver each include a processor in communication with each other. The processors store and execute a program for a selected application configuration.

Acoustophoretic devices for separating particles from a non-flowing host fluid are disclosed. The devices include a substantially acoustically transparent container and a separation unit, with the container being placed within the separation unit. An ultrasonic transducer in the separation unit creates a planar or multi-dimensional acoustic standing wave within the container, trapping particles disposed within the non-flowing fluid and causing them to coalesce or agglomerate, then separate due to buoyancy or gravity forces.

An acoustophoretic device is disclosed. The acoustophoretic device includes an acoustic chamber, an ultrasonic transducer, and a reflector. The ultrasonic transducer includes a piezoelectric material driven by a voltage signal to create a multi-dimensional acoustic standing wave in the acoustic chamber emanating from a non-planar face of the piezoelectric material. A method for separating a second fluid or a particulate from a host fluid is also disclosed. The method includes flowing the mixture through an acoustophoretic device. A voltage signal is sent to drive the ultrasonic transducer to create the multi-dimensional acoustic standing wave in the acoustic chamber such that the second fluid or particulate is continuously trapped in the standing wave, and then agglomerates, aggregates, clumps, or coalesces together, and subsequently rises or settles out of the host fluid due to buoyancy or gravity forces, and exits the acoustic chamber.

An electroacoustic transducer is provided that combines the properties and advantages of the known concepts of the thickness mode transducer and of the bending transducer with each other. For this purpose, an electroacoustic transducer is provided, which includes a housing and an oscillating structure. The oscillating structure is formed by at least one piezoelectric element, a diaphragm, and an acoustic transmitter. It is provided that the diaphragm is designed as a bending transducer, and the acoustic transmitter is designed as a thickness mode transducer.