An ultrasonic actuator with increased radiating surface is presented. The increased radiating surface is provided by a plurality of piezoelectric stacks that are each compressed by action of a respective bolt against a common backing structure of the actuator. According to one aspect, each of the stacks includes a plurality of stacked piezoelectric rings with the respective bolt arranged through the central opening of the rings. According to another aspect, one or both of the backing structure and the horn of the actuator include tuning grooves and/or tuning slots to produce amplitude uniformity of displacement through the actuator. According to another aspect, the radiating surface has a symmetrical shape about an axial direction of the actuator with a lateral dimension that is in a range between one quarter and one half of the wavelength of operation of the actuator.

An ultrasonic actuator with increased radiating surface is presented. The increased radiating surface is provided by a plurality of piezoelectric stacks that are each compressed by action of a respective bolt against a common backing structure of the actuator. According to one aspect, each of the stacks includes a plurality of stacked piezoelectric rings with the respective bolt arranged through the central opening of the rings. According to another aspect, one or both of the backing structure and the horn of the actuator include tuning grooves and/or tuning slots to produce amplitude uniformity of displacement through the actuator. According to another aspect, the radiating surface has a symmetrical shape about an axial direction of the actuator with a lateral dimension that is in a range between one quarter and one half of the wavelength of operation of the actuator.

An apparatus and system for deploying an acoustic sensor are disclosed. In some embodiments, an acoustic sensor includes a transducer comprising a piezoelectric material layer having a front side from which the transducer is configured to transmit acoustic sensing signals and an opposing back side. A backing material layer comprising an acoustic damping material is coupled at a front side to the back side of the piezoelectric material layer. An acoustic reflector such as may comprise a cavity containing gaseous or liquid fluid is disposed between the front side and a back side of the backing material layer.

A method of forming parts uses a forming tool having a forming surface, and an ultrasonic transducer array on the forming surface.

A vibration device that includes a vibration unit that has a vibrator which vibrates in a plane direction; and a sensor arranged on at least a portion of the vibration unit around the vibrator in a plan view of the vibration unit, and the sensor is constructed to detect a pressing operation in a direction normal to a pressing surface of the vibration device.

A system includes sensor-actuator units fixed onto a plate to be actuated according to at least one predetermined vibratory mode, each sensor-actuator unit having an electromechanical actuator and a deformation or vibratory speed sensor, wherein the electromechanical actuator and the sensor are colocated on the surface, that is to say that the measurement by the sensor is performed in immediate proximity to the electromechanical actuator, this proximity being such that the actuator and the sensor can respectively actuate and measure the same predetermined vibratory mode.

An ultrasonic includes: a piezoelectric layer; an absorbing layer disposed at a lower portion of the piezoelectric layer, configured to absorb an acoustic signal; and a connection part disposed between the piezoelectric layer and the absorbing layer. The connection part may deform at least partially so that a plurality of acoustic signals radiated from the piezoelectric layer due to the connection part have different magnitudes. In the case of the ultrasonic probe, since the magnitude of the acoustic energy radiated from the center of the ultrasonic probe is larger than the magnitude of the acoustic energy radiated from the side of the ultrasonic probe, the directivity of the ultrasonic signal is improved and a side lobe is decreased. In addition, an apodization effect capable of suppressing overlapping between adjacent phases can be obtained by using a difference in the magnitude of the acoustic energy to be radiated.

An ultrasonic device according to an aspect of the present disclosure includes a substrate in which an opening section piercing through the substrate in a thickness direction is provided, a vibration plate provided on the substrate to close the opening section, a piezoelectric element provided in a position corresponding to the opening section on a first surface at the opposite side of the substrate side of the vibration plate, and an elastic layer provided in contact with a second surface at the substrate side of the vibration plate at the inner side of the opening section of the substrate. The elastic layer includes a curved surface recessed to the vibration plate side at the opposite side of the vibration plate side.

An ultrasonic device may include an electromechanical ultrasonic system defined by a predetermined resonant frequency, in which the system may include an ultrasonic transducer coupled to an ultrasonic blade. A method of estimating a state of an end effector of the ultrasonic device may include applying a drive signal defined by a magnitude and a frequency to the ultrasonic transducer, sweeping the frequency of the drive signal from below a first resonance to above the first resonance of the electromagnetic ultrasonic system, measuring and recording, impedance/admittance circle variables R.sub.e, G.sub.e, X.sub.e, and B.sub.e, comparing, the measured impedance/admittance circle variables R.sub.e, G.sub.e, X.sub.e, and B.sub.e to reference impedance/admittance circle variables R.sub.ref, G.sub.ref, X.sub.ref, and B.sub.ref, and determining, a state or condition of the end effector based on the result of the comparison. An electromechanical ultrasonic system may include a control circuit to effect the method.

An MEMS device includes: a first member; a second member forming a sealed space with the first member therebetween; and a third member disposed between the first member and the second member and joined to the first member and the second member, in which the third member has lower rigidity than rigidity of the first member and the second member, and the third member is provided with a communication portion that establishes communication between the sealed space and an external space.