A combination of computer generated Fresnel holograms and light guide substrate with diffractive optical elements for optical display and sighting system

Currently, diffractive optical elements with light guide substrates are used in miniature display systems especially in systems for vehicles, aircraft, and systems, where the observed image overlaps with the real scene. It is possible to get rid of the double image and zero order (this feature is inherent in computer generated hologram Fourier) as a result of synthesis of complex Fresnel hologram. As a result, we can synthesize a complex hologram that is free of the twin image and the zero-order light using a single spatial light modulator. The holograms are recorded with a spatial light modulator in a projection mode. This configuration consists of glass substrate with computer generated holograms Fresnel and diffraction gratings, as a diffractive optical element, for input and output of radiation. Reconstructing beam is incident on the computer generated holograms Fresnel, and then through diffraction grating 1 radiation is introduced into the plate at an angle of TIR and spread in it. When the light reaches the surface of the substrate with a diffraction grating 2, part of the light emerges from it. diffraction gratings are two diffraction gratings, which should have different diffraction to ensure uniform brightness of the observed image. It should be noted that to ensure the non-uniform diffraction efficiency of diffraction grating exit area was divided into multiple zones. Thus, the zonal diffraction grating was recorded with its exposure value. Light beams diffracted on computer generated holograms Fresnel enter and then multiple output from substrate, thus forming for observer an increased image of the test object.