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High resolution transducer up to 2000 MHz
The frequency of 2000 MHz is the worldwide highest practical frequency supplied by SAM TEC for acoustic imaging and analysis, which offers resolution values down to 0,3 µm.
SAM TEC provides transducers from 800 - 2000 MHz for different high resolution applications. There are many situations where for thin coating layers the measurement of the elastic properties of the layer structure could be important to understand the properties of coating processes. Even more desirable in some applications is knowledge of stresses in the layer. It is now possible to make measurements by quantitative acoustic microscopy that will yield this kind of information. Accurate elastic measurements by acoustic microscopy were pioneered using cylindrical lenses which brought the acoustic beam to a focus along a line. This means that Rayleigh waves were excited in the surface of the material in one azimuthal direction in the surface only, so that even if the sample was anisotropic only one Rayleigh velocity would be involved. Line-focus-beam lenses give particularly well defined oscillations in the variation of signal with defocus - the so-called V(z) curve - and by suitable Fourier analysis surface wave velocities can be determined from the period of the oscillations with an accuracy which can exceed 0.1 %. The attenuation of surface waves can also be measured.
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