TRANSDUSER DAN FILTER GELOMBANG AKUSTIK PERMUKAAN TIPE REFLEKSI BALIK

摘要

PROBLEM TO BE SOLVED: To provide the structure of an IDT electrode, which improves attenuation quantity on a high pass side of a passband neighbor hood and the spurious signal of the region and an SAW device that uses it. ;SOLUTION: This surface wave converter arranges an electrode finger 1 of a width W1, and an electrode finger 2 of a width W2 in a gap g1 and an electrode finger 3 of a width W3 in a gap g2 as one base section (λ) on a piezoelectric substrate and also drives with the fingers 1 and 3 in-phase and the finger 2 out of phase, and furthermore, setting W1=W3, g1=g2. Thus, it is possible to form a filter, which improves the attenuation frequency of a passband neighborhood drastically by cascade connection of a vertical connection multiple mode SAW filter, that is configured by using a normal IDT and a vertical connection multiple mode SAW filter that is configured by using an IDT electrode. Consequently, it exhibits a striking effect at producing of a SAW filter.;COPYRIGHT: (C)1999,JPO