Patent ID: 9236848
Filing Date: 2016-01-12
CPC Classification: H03H

Claim Text:
1. A filter comprising: a primary transducer connected to a primary terminal; a secondary transducer connected to a plurality of secondary terminals; and a coupling transducer for mechanically coupling the primary transducer and the secondary transducer, wherein each of the primary transducer, the secondary transducer, and the coupling transducer comprises an upper electrode, a lower electrode arranged below the upper electrode, and a piezoelectric film interposed between the upper electrode and the lower electrode, wherein the primary transducer and the secondary transducer are arranged on the upper electrode of the coupling transducer, wherein the lower electrode of the primary transducer, the lower electrode of the secondary transducer, and the upper electrode of the coupling transducer are grounded, wherein the primary transducer includes two top electrodes connected in parallel to the primary terminal, wherein the secondary transducer includes a plurality of top electrodes respectively connected to the plurality of secondary terminals, wherein the primary transducer includes two excitation portions, wherein the secondary transducer includes a plurality of excitation portions, and wherein, with respect to the primary transducer and the secondary transducer, respective areas of the two excitation portions and respective areas of the plurality of excitation portions are equal to one another.