BRANCHING FILTER

摘要

PROBLEM TO BE SOLVED: To provide an acoustic wave element for increasing the pass band width in amplitude characteristic of a filter.SOLUTION: An acoustic wave element 10 has a piezoelectric substrate 11 with a principal front face 12 and a rear face 13 of which are mirror polished. The principal front face 12 includes: an input interdigital electrode 14 and an output interdigital electrode 15 formed thereon. A bulk wave 16 emitted from the input interdigital electrode 14 is reflected on the rear face 13 and is received by the output interdigital electrode 15. At least one of the input interdigital electrode 14 and the output interdigital electrode 15 is processed with an intersection width weighting.