A squirter sonar transducer is provided as a body having a first end and a second end. The body is a cylindrical wall having a length and an inner diameter with a piezoelectric ring actuator disposed within the cylindrical wall. A baseplate is connected to the first end of the body and caps the first end. The second end of the body is open to define a resonator cavity within the body. The baseplate is made of a solid mass having a thickness of approximately fifty percent of the length of the cylindrical wall and has a recess approximately fifty percent of the thickness with a recess diameter equal to the inner diameter of the cylindrical wall.

A system for producing sound waves in a medium, the system comprising: at least two first free-flooded ring transducers centered about a first axis, the first free-flooded ring transducers being substantially cylindrical and having an axial gap of height g therebetween such that they form a first column; and at least one cylindrical body centered about the first axis nested in the first column, such that the cylindrical body is aligned with the axial gap. The cylindrical body may be a tweeter free-flooded ring transducer. This provides for improved wideband performance in a free flooded ring array.

Injectable acoustic tags and a process of making are described for tracking host animals in up to three dimensions. The injectable acoustic tags reduce adverse biological effects and have a reduced cost of manufacture compared with conventional surgically implanted tags. The injectable tags are powered by a single power source with a lifetime of greater than 30 days. The injectable tags have an enhanced acoustic signal transmission range that enhances detection probability for tracking of host animals.

A multi-element fiber scanner for scanning electromagnetic imaging radiation includes a base having a base plane and a longitudinal axis orthogonal to the base plane and a first fiber link passing through the base in a direction parallel to the longitudinal axis. The first fiber link is operatively coupled to at least one electromagnetic radiation source. The multi-element fiber scanner also includes a plurality of additional links joined to the base and extending from the base and a retention collar disposed a predetermined distance along the longitudinal axis from the base. The first fiber link and the plurality of fiber links are joined to the retention collar.

An imaging unit includes an outermost layer lens, a housing, a vibrator, a piezoelectric element, an inner layer lens, a fixing portion, an imaging element, an imaging control substrate, and a case. The vibrator vibrates the outermost layer lens held by the housing. The piezoelectric element is provided on at least one surface of the vibrator. The case is joined to the housing and houses at least the imaging element and the imaging control substrate. Wiring electrically connected to the piezoelectric element extends from an inside of the housing so as to pass a plane including a mounting surface of the imaging control substrate on which the imaging element is mounted.

An electroacoustic transducer includes: a housing; an oscillating structure including at least one disk-shaped piezoelectric element having first and second surfaces; an acoustic transmitter; and electrical connecting element contacting electrodes of the piezoelectric element. The acoustic transmitter has parallel first and second surfaces, which first surface is joined to the first surface of the piezoelectric element, and which second surface is suitable for emitting and/or receiving sound waves. The distance between the second surface of the acoustic transmitter and the second surface of the piezoelectric element corresponds to of the resonance oscillation wavelength of the oscillating structure. The piezoelectric element is connected to the housing with the aid of a bearing structure which allows transverse strains of the piezoelectric element.

Systems and methods for monitoring organisms within an aquatic environment are described. According to one aspect, an injectable acoustic transmission device includes a body configured to be injected inside of an organism, a transducer within the body and configured to convert a plurality of electrical signals into a plurality of data transmissions which are transmitted externally of the body and the organism, a plurality of circuit components within the body and configured to use electrical energy from a power source to generate the electrical signals which are provided to the transducer, and wherein the transducer defines an internal volume and at least one of the circuit components is provided within the internal volume of the transducer.

A system includes a transducer configured to emit ultrasound in response to receiving an electrical signal from a driving circuit. The transducer includes a first dimension that determines a frequency of the ultrasound and a second dimension that determines an impedance of the transducer. The frequency is independent of the second dimension.

Methods, apparatus, systems are described in conjunction with a watertight housing designed for ultrasonic lens cleaning. An example apparatus includes a transducer having a surface and an opening; a bracket having a first surface, a second surface, a third surface, and an opening, the first surface of the bracket coupled to the surface of the transducer, the opening of the bracket aligned with the opening of the transducer; and a lens having a first surface and a second surface, the first surface of the lens is coupled to the second surface of the bracket, the second surface of the lens coupled to the third surface of the bracket, the lens covering the opening of the transducer and the opening of the bracket.

The ultrasonic transducer includes a case, a piezoelectric vibrator disposed in the case, a wiring member overlapped with the piezoelectric vibrator in the case and inputting signals for vibrating the piezoelectric vibrator received from the outside to the piezoelectric vibrator, and a damper portion provided in the wiring member and adjacent to the piezoelectric vibrator when viewed from the thickness direction of the piezoelectric vibrator.