Electroacoustic transducer for a surface wave operating component

An electroacoustic transducer comprising:

• a first electrode having first fingers connected to a first bus bar;
• a second electrode having second fingers connected to a second bus bar, wherein the first and second fingers interdigitate;
• an active region and edge regions, the edge regions being between the active region and one of the bus bars;
• wherein at least one end of each of the first and second fingers abuts at least one of plural gaps;
• and
• floating metal structures in at least some of the gaps;
• wherein an acoustic wave of wavelength λ is excitable at a resonant frequency, the acoustic wave having a longitudinal and a transverse excitation profile and a longitudinal and a transverse energy density profile, the longitudinal excitation profile being approximately constant and different from the longitudinal energy density profile, and the transverse excitation profile substantially corresponding to the transverse energy density profile;
• wherein the active region has a transverse length W, where W is at least 3λ;
• wherein an edge region has a transverse length D, where λ<D<W;
• wherein transverse positions of the gaps relative to a bus bar vary in order to obtain the transverse excitation profile;
• wherein the first and second fingers comprise finger groups comprised of at least four fingers, each finger group spanning a length of at least two wavelengths;
• wherein each finger group has a finger group pattern comprised of at least one of transverse position size and shape of at least one of the gaps and the floating metal structures,
• the finger groups comprising a first finger group and a second finger group;
• wherein finger group patterns of the first group and the second group substantially coincide;
• and
• wherein the finger group pattern of the first and the second finger group are displaced with respect to one another in a transverse direction.

An electroacoustic transducer comprising:

• a first electrode having first fingers connected to a first bus bar;
• a second electrode having second fingers connected to a second bus bar, wherein the first and second fingers interdigitate;
• an active region and edge regions, the edge regions being between the active region and one of the bus bars;
• wherein at least one end of each of the first and second fingers abuts at least one of plural gaps;
• and
• floating metal structures in at least some of the gaps;
• wherein an acoustic wave of wavelength λ is excitable at a resonant frequency, the acoustic wave having a longitudinal and a transverse excitation profile and a longitudinal and a transverse energy density profile, the longitudinal excitation profile being approximately constant and different from the longitudinal energy density profile, and the transverse excitation profile substantially corresponding to the transverse energy density profile;
• wherein the active region has a transverse length W, where W is at least 3λ;
• wherein an edge region has a transverse length D, where λ<D<W;
• wherein transverse positions of the gaps relative to a bus bar vary in order to obtain the transverse excitation profile;
• wherein the first and second fingers comprise finger groups comprised of at least four fingers, each finger group spanning a length of at least two wavelengths;
• wherein each finger group has a finger group pattern comprised of at least one of transverse positions, sizes and shapes of at least one of the gaps and the floating metal structures;
• wherein the finger group patterns in all finger groups substantially coincide;
• and
• wherein variations in the finger group pattern occur periodically in a longitudinal direction.