Abstract: A surface transverse wave resonator comprises a piezoelectric substrate having at least one surface, wherein said substrate includes a crystalline structure that permits the propagation of transverse waves. The resonator also comprises a transducing set of periodic perturbations which are positioned atop the substrate surface, wherein the transducing set converts electromagnetic energy from an external source into the transverse waves. The resonator further comprises a receiving set of periodic perturbations which are positioned atop the substrate surface remote of the transducing set of periodic perturbations, wherein the receiving set converts the transverse waves into resultant electromagnetic energy. Moreover, the resonator includes a central set of surface-trapping periodic perturbations for maintaining the transverse waves adjacent to the substrate surface, wherein the central set is positioned intermediate the transducing set and the receiving set.

Abstract: The interfering resonances of transverse modes are moade to occur far from the fundamental resonant frequency in a surface acoustic wave (SAW) resonator by connecting a plurality of SAW sub-devices in parallel. The frequency response of this parallel combination is essentially undistorted. Interfering spurious resonances caused by the transverse modes become inconsequential. These devices have a substantially higher power handling capability as compared to conventional resonators with comparable Q. This capability reduces the phase noise of oscillators stabilized by these resonators.

Abstract: A process is provided for trimming a SAW device while the device is energized and operating at its center frequency. By essentially selectively sputter-etching the substrate or the transducer material only, without requiring a masking operation, the center frequency and other electrical characteristics of the SAW device are trimmed in a precise and controlled manner.

Abstract: An integrated optically-controlled 4-port bistable switch having a waveguide directional coupler as one of its elements is disclosed. A photodetector is positioned so as to be sensitive to the optical energy at one output port of the directional coupler and the voltage developed by this photodetector is coupled to electrode elements of the directional coupler. The resulting bistable device permits such functions as remote optical switching to be performed.

Abstract: Acoustical and optical surface wave filters are described wherein the filter characteristic near resonance is provided by cascaded grating resonators. The out-of-band suppression for these resonators is provided by a track changing element that includes a four-port directional coupler having one port connected to receive input energy and a fourth port connected to couple energy into the cascaded grating resonators. Tapered and chirped reflection gratings are positioned so as to selectively reflect energy present at the second and third ports of the directional coupler. In a surface acoustic wave embodiment of the invention, the directional coupler is provided by a multistrip coupler. In an optical embodiment, the directional coupler function is provided by waveguiding structures that are brought sufficiently close to induce 3 dB coupling.