Abstract: A conformal identification apparatus is disclosed. The apparatus presents to an observer through an aided eye at least first and second representational objects corresponding to first and second actual objects. The apparatus includes a map that contains the first and second representational objects; a magnifier disposed between the map and the aided eye that presents a magnified image of a portion of the map including the first and second representational objects; and a support structure that supports the map and the magnifier. The apparatus enables the observer to view the first and second actual objects through an unaided eye simultaneously with viewing the magnified image with the aided eye.

Abstract: A diffraction grating structure in the form of a substrate having a grating portion at an input surface thereof and a solid portion at an output surface thereof. A plurality of diffracting elements are formed in the grating portion, the diffracting elements having grooves, the depths thereof depending on the wavelength of incoming radiation impinging on the diffraction elements. The diffracting elements are formed at a selected slant angle with reference to a direction orthogonal to the plane of the input surface of the grating portion of the structure. The incoming radiation is redirected through the grating structure in a selected direction so as to be effectively concentrated at a selected spatial region.

Abstract: An apparatus for constructing a hologram of one or more two-dimensional images by displaying the images on a variable-reflectance device. An object beam of coherent radiation is directed at the variable-reflectance device to be redirected by the device to a holographic plate, and a reference beam of coherent radiation is directed at the holographic plate to produce, in combination with the redirected object beam, a holographic interference pattern on the plate to form a hologram on the plate. A masking device, preferably electronic, may be provided to selectively expose successive portions of the plate corresponding to successive ones of the images to form a multiplex hologram on the plate.

Abstract: A diffraction grating responds to incoming radiation incident thereon within a given range of incidence angles and re-directs such incident radiation from the structure in a selected direction within relatively limited confines. A liquid crystal material is positioned in contact with the diffracting surface of said at least one diffraction structure, the liquid crystal material, when inactivated, having a refractive index substantially the same as that of the diffraction structure. Activation means place the liquid crystal material in an activated state so that the refractive index thereof is substantially different from that of the diffraction structure whereby incoming radiation within a given range of incidence angles is transmitted through the structure and exits in the selected direction.