Surface acoustic wave device

摘要

A surface acoustic wave device including a piezoelectric substrate having NSPUDT behavior and a directionality reversed electrode structure including positive electrode, negative electrode and floating electrode. Positive and negative electrode fingers each having a width of lambda /8 are arranged interdigitally at a pitch of lambda and floating electrode fingers having a width of 3 lambda /8 are arranged between successive positive and negative fingers with an edge distance of lambda /8. A directivity due to NSPUDT behavior of the substrate can be reversed. Positive and negative electrode fingers are arranged interdigitally at a pitch of lambda and between successive positive and negative electrode fingers are arranged floating electrode fingers having a reflecting coefficient different from that of the positive and negative electrodes.