Patent ID: 6525629
Filing Date: 2003-02-25
Classification: H03H

Abstract:
A surface acoustic wave filter comprising:a piezoelectric substrate; an exciting electrode formed on the piezoelectric substrate and exciting a surface acoustic wave; and a receiving electrode receiving the surface acoustic wave, wherein both the exciting and receiving electrodes are provided with interdigital electrode fingers having a period p, wherein one of the exciting and receiving electrodes is constructed of a plurality of interdigital electrode sub-units having substantially the same electrode surface areas occupied by interdigital electrode fingers, and wherein said plurality of interdigital electrode sub-units are disposed in a direction perpendicular to a propagation direction of the excited surface acoustic wave and have a positional relation such that the interdigital electrode sub-units are offset from each other by (nÂ±Â¼)p, wherein n is an integer, in a direction parallel to the propagation direction of the surface acoustic wave.