Various methods and systems are provided for a multi-frequency transducer array. In one example, the transducer array may be fabricated via a wafer scale approach, where a first comb structure, with a first type of element, is formed by dicing a first acoustic stack and a second comb structure, with a second type of element, is formed by dicing a second acoustic stack. Combining the first and second comb structures may form a multi-frequency transducer array.

A sensor device, including a sensor having a sound transducer to emit sonic waves and convert received sonic waves to electrical signals. A sensor evaluation unit carries out surrounding-area monitoring during a normal operation of the sensor, by evaluating electrical signals of the sound transducer. During a monitoring mode of the sensor, a monitoring unit of the sensor device measures an impedance of the sound transducer for different excitation frequencies of excitation signals produced with a signal generator of the sensor device. The sensor device includes a first and a second signal path, which are each connected to the sound transducer and are connectable to the signal generator. To reset the sensor from normal operation to the monitoring mode, a first control unit of the sensor device is configured to decouple the signal generator from the first signal path and to connect it to the second signal path.

A surgical instrument includes a transducer assembly with a housing having a conduit section and a base portion. A fluid passageway is defined through the conduit and base portion, an ultrasonic transducer including a plurality of piezoelectric elements and a plurality of electrodes are arranged in a stack configuration, where an electrode is located between each pair of piezoelectric elements. A first borehole is defined through the ultrasonic transducer and an end mass having a second borehole defined therethrough. A surface of the end mass is positioned adjacent a first end of the ultrasonic transducer, the end mass is configured to engage with the housing, and the conduit section of the housing is configured to pass through the second borehole of the end mass. The end mass is configured to compress the ultrasonic transducer against a surface of the housing when the end mass is engaged with the housing.

Methods, systems and devices are disclosed for controlling self-induced acoustic interference. In one embodiment, a first piezoelectric transducer to which a first excitation signal is applied, generates back side acoustic waves that are transmitted from a back side of the first piezoelectric transducer into a backing material layer. A second piezoelectric transducer coupled to a back side of the backing material layer generates a first calibration response to the back side acoustic waves. An interference signal profile is generated based, at least in part, on the first calibration response and may be used to filter interference signal components and/or to generate a control signal to be applied to the second piezoelectric transducer during measurement cycles.

An ultrasonic transducer module including a first electrode layer, a second electrode layer, a first piezoelectric material layer, a third electrode layer, a fourth electrode layer, a second piezoelectric material layer, and an insulation layer is provided. The first piezoelectric material layer is disposed between the first electrode layer and the second electrode layer. The second electrode layer is disposed between the first piezoelectric material layer and the third electrode layer. The second piezoelectric material layer is disposed between the third electrode layer and the fourth electrode layer. The insulation layer is disposed between the second electrode layer and the third electrode layer.

An apparatus may include an ultrasonic sensor system having a first layer stack and a second layer stack. The first layer stack may include a first ultrasonic transmitter and the second layer stack may include a second ultrasonic transmitter. The first layer stack and/or the second layer stack may include an ultrasonic receiver. A frequency splitting layer may reside between the first layer stack and the second layer stack.

A structure of an acoustic transducer array probe for transmission of acoustic waves from a front radiation surface into an acoustic load material, where said acoustic waves can have frequencies in a high frequency (HF) band and further lower frequency (LF1, . . . , LFn, . . . , LFN) bands with N1, arranged in order of decreasing center frequency. The acoustic waves are transmitted from separate high and lower frequency arrays stacked together with matching layers in a thickness dimension into a layered structure, with at least a common radiation surface for said high and lower frequency bands. At least for said common radiation surface at least one lower frequency LFn electro-acoustic structure (n=1, . . . , N) comprises a piezoelectric array with an acoustic isolation section to its front face. The acoustic isolation section includes to the front a section composed of a sequence of L3 matching layers with interchanging low and high characteristic impedances, where the front layer of said section is one of i) a lower characteristic impedance layer, and ii) a higher characteristic impedance layer, and where at least one lower characteristic impedance layer is made of a homogeneous material.

A touch feedback and sensing device includes a circuit board, a piezoelectric ceramic actuator on the circuit board; and at least one strain sensor on the circuit board. The piezoelectric ceramic actuator includes a piezoelectric ceramic block, a cathode and an anode on the piezoelectric ceramic block. Different voltages are applied to the cathode and the anode to vibrate the piezoelectric ceramic block. The circuit board vibrates with vibration of the piezoelectric ceramic block. The at least one strain sensor is configured to detect and monitor vibration of the circuit board.

A dual frequency ultrasound transducer includes a high frequency ultrasound array and a low frequency transducer positioned behind or proximal to the high frequency ultrasound array. In one embodiment, a dampening material is positioned between a rear surface of the high frequency array and the a front surface of the low frequency array. The dampening preferably is high absorbing of signals at the frequency of the high frequency array but passes signals at the frequency of the low frequency transducer with little attenuation. In additional, or alternatively, the low frequency can angled with respect to the plane of the high frequency transducer to reduce inter-stack multipath reflections. Beamforming delays compensate for the differences in physical distances between the elements of the low frequency transducer and the plane of the high frequency transducer.

Provided is an ultrasonic transducer and a preparation method thereof. The ultrasonic transducer includes a housing. A piezoelectric layer is disposed in the housing and includes at least two piezoelectric array elements. A frequency interval between the piezoelectric array elements is 50 kHz to 1.2 MHz. An acoustic lens is disposed at a front end of the piezoelectric layer and is used for ensuring that the piezoelectric array elements having different frequencies have a common focus.