Ultrasound is used to detect the proximity of an object and whether the object touches a body of an electronic device. A transducer may produce ultrasonic waves to air and to the device body simultaneously. The transducer is connected to the body, allowing a vibration of the ultrasonic waves to travel in the body. The vibration characteristics, for example the decay, change in the body when the body is touched. The decay may be analyzed to detect the touch. The transducer produces the ultrasonic waves to the airspace in proximity to the electronic device. Waves returning from the airspace, for example, after reflecting back from a proximate object, are analyzed and proximity or a gesture of the object may be detected.

An acoustic device includes a micro-machined acoustic transducer element, an acoustically attenuating region, and an acoustic matching region arranged between the acoustic transducer element and the acoustically attenuating region. The acoustic transducer element is formed in a first substrate housing a cavity delimiting a membrane. A second substrate of semiconductor material integrating an electronic circuit is arranged between the acoustic transducer element and the acoustically attenuating region. The acoustic matching region has a first interface with the second substrate and a second interface with the acoustically attenuating region. The acoustic matching region has an impedance matched to the impedance of the second substrate in proximity of the first interface, and an impedance matched to the acoustically attenuating region in proximity of the second interface.

An ultrasonic transducer having a flexible printed circuit board with a thick metal layer and a manufacturing method thereof are disclosed. The ultrasonic transducer, according to an embodiment of the present invention, comprises: an active element that generates an ultrasonic signal, wherein the active element has a thickness of ¼λ or less at the center frequency of the generated ultrasonic signal; and a flexible printed circuit board that includes a metal layer with a predetermined thickness, which is formed on one surface of the active element and is electrically connected to the active element, wherein the metal layer blocks ultrasonic waves that propagate in an opposite direction to a predetermined travel path of the ultrasonic waves.

An ultrasonic transducer for an ultrasonic flow meter, with a transducer housing, with a transducer element for generating and/or for receiving ultrasonic signals and with an emitting element, the emitting element being exposed to ultrasonic signals at least indirectly from the transducer element and emitting the ultrasonic signals via one end face on one front side of the emitting element into the vicinity bordering the ultrasonic transducer and/or the emitting element picking up ultrasonic signals from the vicinity via one end face on one front side of the emitting element and transmitting them at least indirectly to the transducer element. A good directional action in spite of small dimensions is achieved by the emitting element being connected to the transducer housing via a connecting element and being free standing on its periphery on the front side such that it can oscillate freely on the periphery.

Provided is a method for controlling an ultrasonic motor to reduce noise sounding during low-speed rotation in a surveying instrument adopting the ultrasonic motor for a rotary shaft, and a surveying instrument for the same. In a method for controlling an ultrasonic motor according to an aspect of the present invention, in a low-speed rotation range of an ultrasonic motor, a ratio of an acceleration period as a time of application of the drive signal in a control cycle is controlled, and a time to start the acceleration period is randomly shifted for each control cycle. In a method for controlling an ultrasonic motor according to another aspect, a time to start the acceleration period is regularly shifted for each control cycle. In a method for controlling an ultrasonic motor according to still another aspect, second-half acceleration control and first-half acceleration control are alternately repeated.

Transducer assemblies that can be used in acoustophoretic systems are disclosed. The acoustophoretic systems including the transducer assemblies and methods of operating the acoustophoretic systems are also disclosed. The transducer assemblies include a housing, a polymeric film attached to the housing, and a piezoelectric material attached to the polymeric film. The piezoelectric material is not attached to, and does not come in direct contact with, the housing. The piezoelectric material is configured to be driven by a drive signal to create a multi-dimensional acoustic standing wave. The piezoelectric material can be attached to the polymer film by an adhesive coating on the polymer film.

There is provided an ultrasound probe capable of efficiently discharging heat generated in a plurality of piezoelectric elements to the outside. A heat collecting portion that includes at least one heat conducting path and is formed of a material having a higher thermal conductivity than a backing member collects heat from a plurality of piezoelectric elements, and a heat exhausting portion connected to the heat collecting portion discharges the heat collected in the heat collecting portion to the outside. The heat conducting path extends in a thickness direction within the backing member and has a distal end exposed from the top surface of the backing member facing the bottom surface of each of the plurality of piezoelectric elements.

In accordance with embodiments of the present disclosure, systems and methods for improving performance of ultrasonic transducers, particularly those used in borehole environments, are provided. The disclosed ultrasonic transducers all feature a backing element that is a ceramic backing material. The ceramic backing material may include a solid piece of ceramic material that is disposed on a back end of a piezoelectric element used in the ultrasonic transducer. The disclosed ceramic backing material may be used to mechanically match the backing element to the piezoelectric source element, while minimizing the amplitude of reflections of the ultrasonic pulse generated by the piezoelectric element and reflected at the far end of the backing element. This ceramic backing material may provide consistent performance regardless of the surrounding pressure and temperature, making it particularly useful in borehole applications.

An elastic wave device includes a substrate including a piezoelectric material layer and an IDT electrode on the piezoelectric material layer. The IDT electrode includes a Pt film, a Ti film on the Pt film, and an Al-based metal film on the Ti film. The Ti film is quasi-single-crystalline.

An acoustic wave detection probe includes a light projection section that emits measuring light to be projected onto a subject, an acoustic wave transducer disposed adjacent to the light projection section and capable of detecting an acoustic wave, an acoustic lens provided on a detection side of the acoustic wave transducer, and a housing accommodating the light projection section, the acoustic wave transducer, and the acoustic lens, in which the acoustic lens and a surface portion of the housing adjacent to the acoustic lens are formed to have an optical property in which the average diffuse reflection factor is 85% or more and the average absorption factor is 10% or less in a wavelength range of the measuring light.