Patent ID: 8614534
Filing Date: 2013-12-24
Classification: H03H

Abstract:
1. Transducer having natural unidirectionality for surface acoustic waves, in which the interdigital electrode structure is disposed on a piezoelectric crystal substrate ( 1 ) that is built up from interdigital transducers ( 2 ) that consist of collector electrodes ( 3 ; 4 ) and prongs ( 21 ; 22 ; 23 ; 24 ), whereby at least two of the prongs ( 21 ; 23 ) ( 22 ; 24 ) form a transducer cell that has at least one excitation center for exciting an electrical potential wave and at least one reflection center for reflecting electrical potential waves, wherein a) the prongs ( b) the derivation dv/dθ=0 holds true for the direction R, where v is the phase velocity of the surface wave and θ is an angle deviation of the perpendicular to the prong direction from this direction R, whereby, however, the directions perpendicular to the mirror plane of the substrate crystal are excepted,