| 摘要 |
<p>A reflectionless surface acoustic wave transducer is proposed which has first and second opposed conductive transducer pads (44,46) on a substrate (42) of piezo-electric material. A plurality of groups (52,54,56,58) of N interdigitated lambda /4 electrodes (48,50) extend from the opposed pads to form an elongate transducer. Each group of N interdigitated electrodes has a spacing within the group of lambda /4 and the spaces between adjacent groups of the interdigitated electrodes are lambda /2 such that adjacent groups cancel reflections from each other thereby establishing a reflectionless surface acoustic wave transducer which may be modified to provide weak unidirectionality.</p> |
