Disclosed is a display device. The display device comprising a substrate, a display area including a fingerprint recognition area on the substrate, a support substrate configured to support the substrate, a fingerprint sensor positioned under a rear side of the support substrate and configured to output ultrasonic to the fingerprint recognition area, and an EMI (electromagnetic interference) shield member positioned between the support substrate and the fingerprint sensor.

An imaging system includes: a transceiver cell for generating a pressure wave and converting an external pressure wave into an electrical signal; and a control unit for controlling an operation of the transceiver cell. The transceiver cell includes: a substrate; at least one membrane suspending from the substrate; and a plurality of transducer elements mounted on the at least one membrane. Each of the plurality of transducer elements has a bottom electrode, a piezoelectric layer on bottom electrode, and at least one top electrode on the piezoelectric layer. Each of the plurality of transducer element generates a bending moment in response to applying an electrical potential across the bottom electrode and the at least one top electrode and develops an electrical charge in response to a bending moment due to the external pressure wave.

The present disclosure provides an ultrasonic sensor, a method for driving the same, and a method for manufacturing the same. The ultrasonic sensor includes a back plate, a sounding structure on the back plate and a backing layer on a side of the sounding structure distal to the back plate; the sounding structure includes a plurality of emitting electrodes, an opposite electrode, a piezoelectric layer and a plurality of signal leads, and the plurality of emitting electrodes and the opposite electrode are respectively arranged on two sides of the piezoelectric layer; and the plurality of emitting electrodes are arranged in an array, and each of the emitting electrodes is individually coupled to one of the signal leads. The ultrasonic sensor may achieve an independent control for each patterned electrode such that the ultrasonic sensor may be used as a point sound source.

Provided is a piezoelectric device and an MEMS device whose size can be reduced. The piezoelectric device includes: a first substrate that includes a first surface on which a piezoelectric element and a first electrode coupled to the piezoelectric element are disposed; a second substrate that includes a second surface on which a second electrode configured to be coupled to a control circuit is disposed; and a third substrate that is disposed between the first substrate and the second substrate, and includes a third surface bonded to the first surface and a fourth surface facing the second surface, in which the third substrate has a through hole passing through from the third surface to the fourth surface, and a third electrode provided in the through hole and coupled to the first electrode, and the second electrode is coupled to the third electrode and is electrically coupled to the first electrode via the third electrode.

The present disclosure relates to a flexible vibration film and a display apparatus having the same. A flexible vibration film includes: a vibration layer; a first electrode layer disposed on a bottom surface of the vibration layer; and a second electrode layer disposed on a top surface of the vibration layer, wherein the vibration layer includes: a first vibration unit having a first vibration characteristics; a second vibration unit having a second vibration characteristics; and a flexible insulating part disposed between the first vibration unit and the second vibration unit, and wherein the first electrode layer includes: a first part corresponding to the first vibration unit; and a second part corresponding to the second vibration unit.

An ultrasonic sensing module, an ultrasonic sensing device and a control method thereof, and a display device. The ultrasonic sensing module includes a first electrode layer, a piezoelectric layer, a receiving electrode layer and an emission electrode layer. The first electrode layer is on a first side of the piezoelectric layer; the receiving electrode layer and the emission electrode layer insulated from the receiving electrode layer are on a second side of the piezoelectric layer; and the second side is opposite to the first side.

An ultrasonic sensor and a display device and may drive a plurality of sensing pixels disposed in the ultrasonic sensor simultaneously to transmit an ultrasonic wave, may make a first electrode disposed in a sensing pixel to be floated at a timing receiving a reflected signal to store the signal, and then may perform a sensing sequentially. Therefore, as an accurate sensing may be possible while reducing a duration and a number of an ultrasonic wave transmitting, a sensitivity and an accuracy of a sensing may be maintained while improving a driving efficiency of the ultrasonic sensor.

A piezoelectric element has a diaphragm, a first electrode on the diaphragm, a piezoelectric layer on the first electrode, and a second electrode on the piezoelectric layer. The piezoelectric layer is a stack of multiple piezoelectric films and is made of a perovskite composite oxide containing lead, zirconium, and titanium and represented by the general formula ABO.sub.3, with the molar ratio of the A-site to the B-site (A/B) in the perovskite composite oxide being 1.14 or more and 1.22 or less. In current-time curve measurement, the activation energy calculated from relaxation current using an Arrhenius plot is 0.6 [eV] or less. The relaxation current is the amount of current at the time at which a downward trend in current turns upward.

A haptic stimulator includes a multilayer sheet with a piezoelectric or electroactive polymer layer adapted to mechanically deform upon application of voltage, the multilayer sheet secured to a substrate, and a source of electrical stimulation coupled to drive electrodes on the polymer layer with an AC signal to vibrate the polymer layer. In particular embodiments, the polymer contains polyvinylidene fluoride, and electrodes are patterned to control local electric fields. Another haptic stimulator has first and second electrodes with an air gap and an insulating sheet between first and second electrodes, with an AC voltage driver connecting to the electrodes. In a method of providing haptic stimulation to skin an alternating current supply drives first and second electrodes, the electrodes disposed upon either a piezoelectric or electroactive polymer sheet, vibrating the polymer layer by driving the electrodes; and coupling vibrations of the polymer layer to the sensate skin.

A transceiver includes an array of pMUT elements, where each pMUT element includes: a substrate; a membrane suspending from the substrate; a bottom electrode disposed on the membrane; a piezoelectric layer disposed on the bottom electrode; and a first electrode disposed on the piezoelectric layer. Each pMUT element exhibits one or more modes of vibration.