Provided are a haptic feedback fiber body, a haptic feedback fabric, and a wearable device. The haptic feedback fiber body can include a core fiber having a first electrode to surround the outer surface thereof, and a vibrating fiber, provided so as to intermittently contact the outer surface of the core fiber, including a second electrode on the inner surface thereof, wherein a piezoelectric polymer is provided on the outer surface of the first electrode or on the inner surface of the second electrode to generate fretting vibrations when the polymer is in close contact with the first electrode or the second electrode on which the piezoelectric polymer is disposed opposite to each other.

A sonar transmit array (11), comprising: a plurality of transmitters configured to generate an acoustic sonar signal, wherein at least one of the transmitters is a polyvinylidene difluoride, PVDF, piezoelectric device configured to generate at least part of the acoustic sonar signal. Some embodiments, include a receive array (12) and the associated receive array circuitry (14).

This application relates to methods and apparatus for driving a transducer with switching drivers. A driver circuit has first and second switching drivers for driving the transducer in a bridge-tied-load configuration, each of the switching drivers having a respective output stage for controllably switching the respective driver output node between high and low switching voltages with a controlled duty cycle. Each of switching drivers is operable in a plurality of different driver modes, wherein the switching voltages are different in said different driver modes. A controller controls the driver mode of operation and the duty cycle of the switching drivers based on the input signal. The controller is configured to control the duty cycles of the first and second switching drivers within defined minimum and maximum limits of duty cycles; and to transition between driver modes of operation when the duty cycle of one of the switching drivers reaches a duty cycle limit.

Described herein are methods and apparatuses for packaging an ultrasound-on-a-chip. An ultrasound-on-a-chip may be coupled to a redistribution layer and to an interposer layer. Encapsulation may encapsulate the ultrasound-on-a-chip device and first metal pillars may extend through the encapsulation and electrically couple to the redistribution layer. Second metal pillars may extend through the interposer layer. The interposer layer may include aluminum nitride. The first metal pillars may be electrically coupled to the second metal pillars. A printed circuit board may be coupled to the interposer layer.

A display device includes a display panel, a bracket disposed on a first surface of the display panel, and a first vibrating device disposed between the first surface of the display panel and a first surface of the bracket which faces the first surface of the display panel. The first vibrating device is configured to output a first sound and provide a haptic feedback by vibrating the display panel and the bracket.

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.

This application relates to methods and apparatus for driving a transducer with switching drivers. A driver circuit has first and second switching drivers for driving the transducer in a bridge-tied-load configuration, each of the switching drivers having a respective output stage for controllably switching the respective driver output node between high and low switching voltages with a controlled duty cycle. Each of switching drivers is operable in a plurality of different driver modes, wherein the switching voltages are different in said different driver modes. A controller controls the driver mode of operation and the duty cycle of the switching drivers based on the input signal. The controller is configured to control the duty cycles of the first and second switching drivers within defined minimum and maximum limits of duty cycles; and to transition between driver modes of operation when the duty cycle of one of the switching drivers reaches a duty cycle limit.

A piezoelectric polyvinylidene fluoride (PVDF) material, a method for manufacturing the same, and a fingerprint recognition module are provided. The polyvinylidene PVDF material includes PVDF, a first solvent, a second solvent, a fluorosurfactant, and an inducing material. Material of the inducing material is one of carbon nanotubes, carbon black, and gold nanorods. Because of the high anisotropy of the inducing material, molecular orientation of the PVDF material is induced, thereby improving piezoelectric performance of the piezoelectric PVDF material. Problems of conventional piezoelectric PVDF materials, which are used in ultrasonic fingerprint recognition modules, such as poor piezoelectric performance and high-energy loss are improved.

The vibration-type-motor driving apparatus includes a vibration-type motor including a vibrator on which vibration is excited by an electro-mechanical energy conversion element, a shaft that supports the vibrator, and a rotor that contacts the vibrator to be rotated thereby. A first end portion of the shaft is moved with the vibration of the vibrator. The apparatus further includes a housing that houses therein the motor, and a first elastic member that contacts the first end portion of the shaft and is deformable in a direction in which the first end portion vibrates. The first elastic member transfers heat of the shaft to the housing or another member provided inside the housing.

The vibration device includes a diaphragm, and a plurality of piezoelectric films that are arranged at predetermined intervals in a first direction of the diaphragm to face the diaphragm and extend parallel to a second direction orthogonal to the first direction. The diaphragm has at least one slit formed therein and dividing the diaphragm into respective regions. Each of the piezoelectric films are fixed to a respective region of the diaphragm while extending along the second direction in a tensioned state. The piezoelectric films expand and contract in a plane direction when a voltage is applied thereto.