Abstract: Surface wave filter with a slab-shaped substrate of monocrystalline piezoelectric material, particularly lithium niobate, having input and output transducers optionally coupled by means of a coupler on one substrate side. A plastic and/or elastic damping layer are applied for suppressing reflected waves. The damping layer covers at least in some regions, this substrate side except for the area which is bounded by the transducers, the coupler, the ends of the conductor runs and the regions between the transducers and the coupler. The end face edge of the damping layer increases at least in sections, gradually from zero to the value of the layer thickness.

Abstract: A surface wave filter with a wafer-shaped substrate formed of monocrystalline piezoelectric material having a surface, input and output transducers disposed on the surface of the substrate, a coupler for coupling the transducers being spaced apart from the transducers on the surface of the substrate defining zones therebetween, and electric conductor runs being connected to the transducers on the surface of the substrate and having ends, includes a damping layer formed of photoresist material with a plastic base covering substantially the entire surface of the substrate except for a region bounded by the transducers, the coupler, the ends of the electric conductor runs and the zones between the transducers and the coupler, and a method for manufacturing the filter.

Abstract: Surface wave filter with a slab-shaped substrate of monocrystalline piezoelectric material, particularly lithium niobate, having input and output transducers optionally coupled by means of a coupler on one substrate side. A plastic and/or elastic damping layer are applied for suppressing reflected waves. The damping layer covers, at least in some regions, this substrate side except for the area which is bounded by the transducers, the coupler, the ends of the conductor runs and the reions between the transducers and the coupler. The end face edge of the damping layer increases at least in sections, gradually from zero to the value of the layer thickness.