The present disclosure relates to a medical device with respectively at least one hard part with fluid paths for guiding a medical fluid, for example, blood, through the hard part. The medical device also includes a converter and a device for determining a characteristic of the device. The converter is arranged to measure the characteristic of the fluid, while the fluid is present in one of the fluid paths. The characteristic may be geometric characteristic, for example, a fluid path.

Disclosed is a thermo-mechanical actuator comprising a piezo-electric module, the piezo-electric module comprising at least one piezo-electric element, wherein the thermo-mechanical actuator is configured to receive a thermal actuation signal for controlling a thermal behaviour of the piezo-electric module, or provide a thermal sensing signal representative of a thermal state of the piezo-electric module. The thermo-mechanical actuator is configured to receive a mechanical actuation signal for controlling a mechanical behaviour of the piezo-electric module, or provide a mechanical sensing signal representative of a mechanical state of the piezo-electric module. And wherein the thermal actuation signal is configured to create a heat flux within the piezo-electric module and wherein the mechanical actuation signal is configured to deform the piezo-electric module.

In an embodiment a device includes a piezoelectric transducer element and a support connected mechanically to each other thereby forming an assembly, wherein the piezoelectric transducer element and the support are configured to be jointly deformed under an action of a first force, wherein the support includes a neutral fiber arranged inside the support, the neutral fiber configured to not undergo any change in length during a bending of the assembly, and wherein the piezoelectric transducer element includes a ferroelectric polymer layer or a layer having a composite material including a ceramic material and a piezoelectric polymer matrix.

There is disclosed herein a transducer for acoustic communications through a series arrangement of fluid and solid media, the transducer comprising: a signal processor configured to implement a communications scheme at and around a center frequency of at least 1 MHz; a piezoelectric element for activation in accord with the communications scheme; an electrode electrically connected to the signal processor, and being attached to the piezoelectric element; and a substrate, having the piezoelectric element mounted thereon, wherein an aspect of the electrode at the piezoelectric element is approximately equal to the acoustic wavelength of an acoustic wave in the substrate at the center frequency. There is further disclosed a remote monitoring device employing at least one of the transducers described, in concert with a further transducer. Still further, there is disclosed a method of communicating using the transducer described herein.

Micromachined ultrasonic transducer (MUT) arrays capable of multiple resonant modes and techniques for operating them are described, for example to achieve both high frequency and low frequency operation in a same device. In embodiments, various sizes of piezoelectric membranes are fabricated for tuning resonance frequency across the membranes. The variously sized piezoelectric membranes are gradually transitioned across a length of the substrate to mitigate destructive interference between membranes oscillating in different modes and frequencies.

A piezoelectric actuator part which generates a driving force to rotate a mirror part about a rotation axis includes a first actuator part and a second actuator part having a both-end supported beam structure in which base end parts on both sides in an axial direction of the rotation axis are fixed. Upper electrodes and lower electrodes of the first actuator part and the second actuator part are divided to correspond to a stress distribution of principal stresses in a piezoelectric body during resonance mode vibration, a piezoelectric portion corresponding to positions of a first piezoelectric conversion part and third piezoelectric conversion parts and a piezoelectric portion corresponding to positions of second piezoelectric conversion parts and a fourth piezoelectric conversion part generate stresses in opposite directions.

A transducer configured to be used in a downhole tool includes a radiating face to emit or receive an acoustic signal, a front electrode, a central layer behind the front electrode, and a back electrode behind the central layer, having a back face coupled to a backing material. The central layer has a substantially constant thickness throughout and includes a piezo-composite body and an insulating material. A configuration between the piezo-composite body and the insulating material variably reduces the central layer to reduce generation of side lobes.

An ultrasound sensor includes a substrate on which an opening portion is formed; a diaphragm which is provided on the substrate so as to block the opening portion; and ultrasound elements which include a first electrode, a piezoelectric layer and a second electrode and which are laminated on an opposite side to the opening portion of the diaphragm, a portion in which the first electrode, the piezoelectric layer and the second electrode are overlapped is referred to as an active portion, and a portion which is a range to the extent that the diaphragm is oscillatable by driving the active portion is referred to as a movable portion, the active portion is arranged opposite to the movable portion; a resonance frequency adjustment portion is provided on a lateral side of the active portion, at least in a region opposite to the movable portion.

An angular velocity sensor includes a substrate, a lower electrode on the substrate, a piezoelectric body on the lower electrode, and an upper electrode on the piezoelectric body. The piezoelectric body includes a first portion and a second portion above the first portion. The first portion has a side surface connected to a lower surface of the piezoelectric body. The second portion has a side surface connected to an upper surface of the piezoelectric body. A supplementary angle of an angle formed between the upper surface and the side surface of the second portion of the piezoelectric body is smaller than an angle formed between the lower surface and the side surface of the first portion of the piezoelectric body. This angular velocity sensor can effectively prevent stress from concentrating to the piezoelectric body.

A piezoelectric module includes an element substrate that includes a plurality of piezoelectric bodies (piezoelectric elements) arranged in an array, and a plurality of connection electrodes (lower connection electrode and upper connection electrode) that are connected to the piezoelectric body (piezoelectric element) and are drawn between the piezoelectric body (piezoelectric element) and an adjacent piezoelectric body (piezoelectric element), an input and output circuit that is provided on one surface side of the element substrate and independently inputs and outputs a signal from and to each of the connection electrodes (lower connection electrode and upper connection electrode), and columnar electrodes (first through electrode and second through electrode) each of which is provided between each of the connection electrodes (lower connection electrode and upper connection electrode) and the input and output circuit and connects each of the connection electrodes (lower connection electrode and upper connection electrode) and the input and output circuit to each other.