Integrated-optics implementation of an interferometric spectrum analyser

An improved interferometric spectrum analyser system with direction finding capabilities for an emitting source, the type having a holographic element to provide a laser beam source for the system. The laser beam from the source is focused on a light waveguide within which are arranged in asymetrical configuration with respect to the direction of the laser beam source a plurality of antenna signal transducers and a plurality of reference signal transducer, the antenna signal transducers and the reference signal transducers respectively being arranged in adjacent rows in such a manner as to provide acoustic signals propagating in the same direction within the transducer. A lens assembly is positioned with respect to the light waveguide so as to provide a one-dimensional Fourier transform signal on the X-axis of the waveguide by causing the mixing of the Fourier transform signal of the antenna signal and the Fourier transform signal of the reference signal. The analyser according to the present invention is more compact and less sensitive to vibration than currently available systems.