SAW focusing by circular-arc interdigital transducers on YZ-LiNbO/sub 3/

Using the angular spectrum theory and experimental velocity data of surface acoustic waves (SAW) on YZ-LiNbO/sub 3/, the focusing characteristics of a circular-arc interdigital transducer have been demonstrated. The calculated results show that the depth of focus is long and the compressed acoustic beam width is very narrow. The concept of a caustic is shown to be an excellent way of characterizing SAW focusing by a circular-arc interdigital transducer on YZ-LiNbO/sub 3/. Comparison between theoretical and experimental results shows good agreement.<<ETX>>

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