Abstract: An optical switch is disclosed which relies only on a rotatable, reflective concave surface (3) to couple light between an optical source (1) and a preselected one of a plurality of optical receptors (6). The switch is bidirectional, i.e., the position of the source(s) and receptor(s) can be interchanged. Optical fibers may be used as the source(s) and receptor(s). The source, however, may also be chosen from such devices as lasers, light-emitting diodes or any other optical source known to those skilled in the art. Similarly, avalanche photodiodes or the like may be used as optical receptors.The above switch structure requiring only a reflective element is particularly suitable for switching light signals in telecommunication applications. The elimination of the need for a refractive element, such as a lens, provides a structure in which the output signal is independent of wavelength and index of refraction.

Abstract: The present invention relates to a method for reducing the grating lobes associated with phased array antenna arrangements. The present invention, which may be employed with any phased array antenna arrangement, consists of disposing a filtering means capable of blocking the grating lobes at any real focal point in the focal plane of the antenna arrangement. The size of the central region of the filter is determined by the desired field of view at the far-field, and may be adjusted so as to reduce the grating lobes to an admissible level with minimal gain degradation of the main beam.