Abstract: Systems and methods for fabricating multi-functional articles comprised of additively formed gradient materials are provided. The fabrication of multi-functional articles using the additive deposition of gradient alloys represents a paradigm shift from the traditional way that metal alloys and metal/metal alloy parts are fabricated. Since a gradient alloy that transitions from one metal to a different metal cannot be fabricated through any conventional metallurgy techniques, the technique presents many applications. Moreover, the embodiments described identify a broad range of properties and applications.

Abstract: An encoded hologram that produces a first image and a second image pursuant to playback illumination, wherein the first image is resolvable by human vision while the second image is not resolvable by human vision when the playback illumination comprises non-coherent broad band illumination, and wherein the second image is machine readable when the hologram is illuminated with playback illumination that is based on the original reference beam.

Abstract: A hologram exposure system for simultaneously exposing a plurality of holograms in a holographic recording layer, including first optical elements for providing a first reference beam and a first object beam that interfere in the holographic recording layer and are coherently matched relative to each other, and second optical elements for providing a second reference beam and a second object beam that interfere in the holographic recording layer and are coherently matched relative to each other but are coherently mismatched relative to the first reference and object beams, whereby the crosstalk holograms formed by interference of (1) the first reference beam with the second object beam, (2) the first object beam with the second reference beam, (3) the first object beam with the second object beam, and (4) the first reference beam with the second reference have reduced efficiencies.