air-coupled ultrasoundtransducer optimizationimpedance mismatchair-coupled spectroscopymaterials characterizationThe main objective of this study was to apply the air-coupled broad-band ultrasonic spectroscopy in attached transpiring leaves of Vitis vinifera L. to monitor changes in leaf water potential () ...
(either DC-coupled or AC-coupled) and analyzed by an oscilloscope and a spectrum analyzer. An ultrasound transducer (800 kHz) was placed 2 cm above the resonator, aiming at the center of the resonator. (b) Photograph of the capillary-based bottle-shaped ring resonator. (c) Photograph ...
Air-coupled ultrasound has been used to study the manufacture of ceramic components by both slip casting and injection moulding. A capacitance transducer, ... AG Bashford,DA Hutchins - 《Ultrasonics》 被引量: 258发表: 1998年 High-temperature integrated and flexible ultrasonic transducers for nondestr...
Characterization of air-coupled ultrasound transducers in the frequency range 40 kHz–2 MHz using light diffraction tomography M Almqvist, A Holm, HW Persson and K Lindstrom, "Characterization of air- coupled ultrasound transducers in the frequency range 40 kHz-2 MHz using ... M Almqvist,A ...
6) ultrasound transducer 超声换能器 1. Based on the research of inductance capacitance matching circuits of ultrasonic transducer, influence of ultrasound transducer electricity parameter on its matching circuit has been studied. 在研究压电超声换能器电感电容匹配电路原理的基础上,分析换能器工作时,由于...
Transducer housing is a 30 mm diameter Conclusions Passive focusing devices for Air-Coupled Ultrasound (ACU) transducers provide simple methods to concentrate the sound beam into a focus. This helps to improve lateral resolution and increase sensitivity. This work analyzed both theoretical and ...
A reflection non-contact ultrasonic microscope system working both in amplitude and phase difference modes at 2 MHz has been developed using an air-coupled concave transducer made of piezoelectric polymer films of poly(vinylidene fluoride/trifluoroethylene) [P(VDF/TrFE)]. The transducer is composed of...
The transducer, wh... DW Schindel - 《Ultrasonics》 被引量: 298发表: 1998年 Air-coupled ultrasonic estimation of viscoelastic stiffnesses in plates Materials characterization by means of megahertz air-coupled ultrasound is reported in this paper. In plates of composite laminates the reconstruction ...
For the ultrasonic transducer it is provided that the matching layer (A) has an essentially circular cross-section and is bonded to the piezo-electric ceramic (P), which is to be operated in radial resonance, in such a manner, and that the occurring mechanical vibration is coupled out, ...
The frequency of the generated ultrasound is chosen to match the response characteristics of a micromachined air-coupled capacitance transducer for good signal throughput. The system has proven sensitive to surface defects in composite materials, and is well suited for on-line process control ...