| 摘要 |
<p>A surface acoustic wave device comprises, on a lithium tetraborate substrate (10), a central interdigital transducer (21, 31), and first and second interdigital transducers (22, 23, 32, 33) disposed adjacently on both sides of the central interdigital transducer (21, 31) in a propagation direction of surface acoustic waves, or comprises a first such row of transducers (20) and a second such row of transducers (30) connected in cascade to each other. A sum Nc+Ns of a number of the central interdigital transducer pairs Nc, and a total number of the first and second interdigital transducers pairs Ns is set at a suitable range. The surface acoustic wave device has flat group delay times, relatively wide specific band widths, small insertion losses and large attenuation outside the pass band. <IMAGE></p> |
