Saw device with deflection of undesired components - has waveguide to tap-off components propagating obliquely to interdigitated electrodes

摘要

On a piezoelectric substrate (1) are a pair of interdigitated electrodes (2a,2b) and a waveguide device (5-7). The waveguide provides a deflection to at least one of those components of the surface acoustic wave signal which propagates essentially in non-perpendicular directions to the longitudinal direction of the fingers of the comb electrodes (2a,2b). Pref. the waveguide has a structure with a pattern that forms an acoustic cut-point with reference to the substrate. This pattern may be non-parallel to the electrodes to reflect the component. USE - E.g. for TV receiver IF stage filter.