A new treatment of the well-known Sommerfeld solution of the problem of plane-wave diffraction from a perfectly conducting half-plane is reported. We show, in both theory and experiment, that the diffraction field (E-polarization) can be represented as a superposition of real physically existing waves, in contrast to geometrical and boundary waves postulated in Sommerfeld's representation. Our representation includes two pairs of wave components: one pair propagates along the direction of the incident wave, and the other in a mirror-reflected direction. Each wave pair consists of a plane-wave component with an amplitude half that of the incident wave and a nearly plane-wave component with an infinitely extended edge dislocation. On the basis of the proposed interpretation, all features of the half-plane diffraction are explained.

UDC 535.2:621Using a rigorous theory of diffraction, we explain the origin and analyze the structure of a wideangle illuminated area observed when a limited beam is diffracted by the sharp edge of an opaque screen. It is shown that the formed plume has the structure of a cylindrical wave traveling from the screen edge and its amplitude is proportional to the beam amplitude at this edge. The observed structure is Young's boundary wave produced by diffraction of the limited beam.

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Each hologram: optical, digital and computer generated represents the phase and amplitude of an object. Therefore the process of object reconstruction may rely on one of two alternative procedures: optoelectronic direct reconstruction of hologram, which is represented by diffractive structure intensity, and recombining of object phase and amplitude as calculated from wavefront propagation process (here the method is based on singular wave component that is derived from a rigorous Sommerfeld's solution) or numerical reconstruction of digital hologram.In the paper we present the comparison of these two ways of optoelectronic reconstruction. The pros and cons for application of these procedures from image quality point of view are given. The experimental systems based on a Twyman-Green interferometer with two phase and amplitude LCOS or on a single digital hologram or computer generated hologram reconstruction setup are presented. The conclusions of these experiments will be utilized for optimizing of the process of production of security holograms with use of LCOS modulators.

We propose a structure based on combination of multilayer stack of dielectric films and thin metal layer for excitation and enhancement of both s- and p-polarized evanescent waves. It is shown that two different mechanisms of evanescent wave excitation may occur at the same angle of light beam incidence on the structure. Application for evanescent wave polarization holographic recording with the help of this structure is discussed.

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We propose and demonstrate experimentally super-collimation of light beams by an axisymmetric diffractive metamirror—an axisymmetric concentric dielectric ring structure positioned in front of a mirror at a distance of several micrometers. By super-collimation, we mean the formation of a well-collimated beam characterized by a substantial enhancement of its axial component in the far-field domain. In the reported experiments, the axial intensity of the field was enhanced by around six times. Such axisymmetric super-collimators could be especially useful for improving the emission spatial quality of micro-lasers, when integrated as one (or both) resonator mirrors.