Abstract: A guided-wave acoustooptic spectrum analyzer comprises a planar optical waveguide layer with electrodes of a transducer thereon. The electrodes are positioned at the center of a light path under which light is propagated. The light is deflected in response to frequencies of electric signals applied to the electrodes. With the invention, the detectable minimum pulses width of a pulse signal is reduced as compared with the prior art, while the frequency resolution therein is maintained at the same level.

Abstract: In a surface acoustic wave dispersive delay line of the type comprising a substrate made of piezoelectric material along which surface acoustic wave propagates, an input transducer formed on the substrate for producing the surface acoustic wave in response to an input electric signal, a first reflector including a plurality of reflection gatings formed at different spacings on the substrate for reflecting the surface acoustic wave from the input transducer, a second reflector including a plurality of reflection gratings formed at different spacings on the substrate for reflecting the surface acoustic wave reflected by the first reflector, an output transducer for converting the surface acoustic wave reflected by the second reflector into an electric signal, there is provided a device for eliminating concentration of the surface acoustic wave formed by the first and second reflectors.