摘要:
The invention is directed to a piezo-electric transducer having electrodes that adhere well both to ceramic as well as to plastics and that are composed of intrinsically conductive plastic. The invention is also directed to a method for the manufacture thereof. A conductive polymer layer is produced on the surface of a piezo-ceramic component by chemical or anodic oxidation of a monomer. The monomers are selected from the class of 5-member heterocycles containing sulfur or nitrogen as heteroatom, or aniline, azuline, or derivatives of the said compounds. The components provided with the economical electrodes can be advantageously composed to form sandwich-like transducers having plastic intermediate layers that exhibit good electro-acoustical properties.
摘要:
A method for the manufacture of a linear or annular ultrasonics antenna array for the megahertz range, which consists in providing a laminate of alternating layers of unsintered ceramic and spacing layers, the spacing layers being composed of a filler material which is heat fugitive at the sintering temperature of the ceramic, the spacing material also including refractory grains distributed therein of a size which corresponds to the spacing desired between the ceramic layers, sintering the laminate to thereby liberate the filler material and leave voids between the refractory grains, impregnating the resulting laminate with a polymerizable resin to bond the sintered ceramic layers together, and separating the resulting laminate into individual transducer elements.
摘要:
The invention provides an electrode for piezoelectric composites having high acoustic attenuation. The electrode is composed of a first layer having high elasticity and lower conductivity and of a second layer lying thereabove that has higher conductivity. The invention also provides a method for the manufacture thereof. The first layer is an intrinsically conductive plastic directly deposited on the ceramic whose polymerization is initiated by chemical or anodic oxidation of the corresponding monomers. The second layer is fashioned of adequately conductive metal and is preferably first sputtered on or vapor-deposited in a thinner layer and is then subsequently electrolytically reinforced. Piezoelectric composites that exhibit high acoustic attenation and, thus, prevent an acoustic crosstalk between the individual transducer elements can be manufactured from piezoelectric ceramic lamina or foils provided with such electrodes. Such composites also withstand higher mechanical distortion (for example, due to thermal expansion), even if the ceramic is highly porous.
摘要:
A material is disclosed for use as an adaptation layer in ultrasonic transducer units of the type which have a piezo-ceramic transducer. The material is porous, and the acoustic impedance of the material can be adjusted (in one embodiment, to 12.times.10.sup.6 kg/cm.sup.2 s) by adjusting the porosity of the material. In preferred embodiments, the material is piezo-electric and may have a porosity gradient.
摘要翻译:一种材料被公开用作具有压电陶瓷换能器类型的超声换能器单元中的适配层。 该材料是多孔的,并且可以通过调节材料的孔隙率来调节材料的声阻抗(在一个实施例中为12×10 6 kg / cm 2·s)。 在优选的实施方案中,材料是压电的并且可以具有孔隙度梯度。
摘要:
A piezoelectric ceramic powder is, together with a binder, processed to a granulate. This granulate is mixed with a pearl polymer to a mixture. The mixture is pressed to a suitable shape, and then in a first firing step the binder and the pearl polymer are fired out. Preferably the first firing process is followed by a second firing step for sintering. Thereafter mechanical fabrication may take place, to give the end product its shape. The firing out of the pearl polymer results in a porous piezoelectric ceramic, with which, when used in an ultrasonic transducer, a high transducer effectiveness, sharp ultrasonic pulses with little edge radiation as well as a good electric and acoustic adaptation can be achieved.
摘要:
A composite ultrasound transducer (array) contains piezoelectric ceramic transducer elements which radiate substantially in the longitudinal direction, and are embedded in a polymer matrix. The transducer elements have such a geometrical structure, and are arranged relative to each other, so that the development of oscillation modes perpendicular to the longitudinal direction of the transducer elements is suppressed. A method for manufacturing the composite ultrasound transducer includes the steps of filling a plastic form, having a "negative" of the desired shape of the transducer elements, with ceramic slurry, and pyrolyzing the plastic form after the slurry dries therein. The resulting voids between the hardened ceramic elements are filled with polymer to create the overall composite transducer. The transducer elements can thus be given an arbitrary shape and arrangement, such as hexagonal or irregular square structures, having a trapezoidal cross-section in planes parallel to the longitudinal axis of the transducer elements.
摘要:
An ultrasound array has a number of oscillator elements arranged side-by-side, each oscillator element having a trapezoidal cross-section. The oscillator elements are separated from each other by incisions having non-parallel walls, which are co-planar with surfaces of the piezoelectric material comprising the oscillator element. The incisions terminate in a damping member, to which all of the oscillator elements are attached. The incisions are produced with an excimer laser whose laser beam is focused onto a prepared layered material, with the incisions proceeding along a line.
摘要:
A device for detecting at least one substance of a fluid includes at least one piezo-acoustic resonator with at least one piezo layer, an electrode arranged on the piezo-electric layer, at least one other electrode arranged on the piezo-electric layer and a surface section used for sorption of the substance of the fluid. The piezo-electric layer, the electrodes and the surface section are disposed in such a way that electric control of the electrodes leads to an oscillation of the resonator at a resonance frequency which depends upon the amount of the substance which is sorbed on the surface section. The thickness of the pioelectric layer is in the region of 0.5 to 20 μm and the resonance frequency of the oscillation ranges from 500 MHz to 2 GHz. The device is a mass sensor with a piezo-acoustic high-frequency thin film resonator.
摘要:
Biochip for capacitive stimulation and/or detection of biological tissues. The biochip has a carrier structure, at least one stimulation and/or sensor device, which is arranged in or at the carrier structure, and at least one dielectric layer, one layer area of which is arranged at the stimulation and/or sensor device and the opposite layer area of which forms a stimulation and/or sensor area for capacitive simulation and/or detection of biological tissues, wherein the dielectric layer comprises TiO2.
摘要:
A thin-film technology multi-layer capacitor with enhanced capacitance and/or reduced space requirement. The dielectric layers of which are alternately disposed between electrode layers on a substrate. Through alternate electrode layer connections, parallel interconnection of the individual capacitor layers is obtained. The result is that the individual capacitances are additive, while the temperature response can be optimized by a suitable choice or combination of different dielectric layers.