Abstract: A process for making a multilayer photopolymer hologram structure without intervening adhesive layers between component photopolymer layers.

Abstract: Method and apparatus for monitoring wavelength shift in a holographic light protection filter to determine if the hologram has been damaged by moisture. The hologram is provided with first, second and third areas. The first area is an extra moisture protected area covered by a moisture resistant material. The second area is adjacent to the first area and is recorded at a different wavelength than the bulk of the hologram. The third area is the remainder of the hologram. The user compares light reflections at these specific areas of the hologram and observes color variations to determine if the hologram has been damaged by moisture. In another embodiment, scribe lines are drawn in the hologram through the three areas. The user detects moisture damage by observing the apparent displacement of these scribe lines in the three areas when viewed through a diffraction grating.

Abstract: A hologram exposure system that includes a holographic recording medium, a holographic prism adjacent the holographic recording medium for most efficiently diffracting light of a predetermined wavelength and at a predetermined incidence angle, a first monochromatic beam directed toward the holographic prism at the predetermined incidence angle, and a second monochromatic beam directed toward the holographic prism at an incidence angle that allows the second monochromatic beam to be transmitted by the holographic prism without any diffraction. The holographic prism diffracts the first monochromatic beam and transmits the second monochromatic beam without any diffraction to produce a diffracted first construction beam and a non-diffracted second construction beam which interfere in the holographic recording medium to form holographic fringes therein.

Abstract: A stoplight system that includes a light source for providing a light output, and an array of non-overlapping lenslets comprised of first lenslets and second lenslets, each first lenslet configured to refract a portion of the light output of the light source into a first predetermined angular field comprising a central angular region having vertical and horizontal extent, and each second lenslet configured to refract a portion of the light output of the light source into a second predetermined angular field comprising first and second peripheral angular regions that are horizontally on either side of the central angular region, whereby the portions of the light output of the light source that are refracted by the first and second lenslets form stoplight illumination.

Abstract: A hologram structure including a hologram layer including a half-tone pattern of transparent areas and reflection hologram areas, and a non-hologram half-tone pattern of areas that are substantially opaque to the range of wavelengths that comprises the spectral bandwidth of the holograms areas located adjacent the hologram layer, wherein the hologram areas are superimposed with selected areas of the non-hologram half-tone pattern.

Abstract: A hologram copying system that includes a first reconstruction beam, a second reconstruction beam that is incoherent with respect to the first reconstruction beam, a first master hologram responsive to the first reconstruction beam for producing a first diffracted beam, a second master hologram responsive to the second reconstruction beam for producing a second diffracted beam, and a holographic recording layer responsive to the first and second reconstruction beams and the first and second diffracted beams, whereby a first hologram is formed by interference of the first reconstruction beam and the first diffracted beam, and a second hologram is formed by interference of the second reconstruction beam and the second diffracted beam.

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 structure for use in a holographic center high mounted stoplight system for a vehicle. The hologram structure includes an illumination source for providing a reconstruction beam, a first array of non-overlapping hologram cells and non-hologram cells, and a second array of non-overlapping hologram and non-hologram cells. Each hologram cell of the first array produces a specular image that is viewable in a first predetermined angular field pursuant to diffraction of a portion of the reconstruction beam, and each hologram cell of the second array produces a diffuse image that is viewable in a second predetermined angular field pursuant to diffraction of a portion of the reconstruction beam. The specular images and diffuse images produced by the first and second holograms form stoplight illumination.

Abstract: A hologram structure for use in a holographic center high mounted stoplight system for a vehicle. The hologram structure includes first and second hologram layers laminarly secured to each other, each having a plurality of holographic lenses formed therein, each holographic lens being configured to diffract light into a predetermined solid angular region.

Abstract: A hologram structure including a plurality of holograms having substantially identical reconstruction characteristics disposed on a substrate for rotation about a rotation axis and containing segments of a composite image. The holograms are angularly offset relative to each other about a rotation axis such that the composite image is visible over at least one narrow solid angular region pursuant to rotation of the holograms about the rotation axis and illumination of the holograms with a reconstruction beam.

Abstract: A hologram structure for use in a holographic center high mounted stoplight system for a vehicle. The hologram structure includes first and second hologram layers laminarly secured to each other, each having a plurality of bright hologram cells and dim hologram cells formed therein, and each hologram cell being configured to diffract light into a predetermined solid angular region. The bright hologram cells and the dim hologram cells of each hologram are arranged in a pattern to produce a recognizable pattern of bright and dim areas.

Abstract: A display hologram structure including a display hologram configured for reconstruction with a playback beam having a predetermined wavefront configuration, and a light configuring hologram that provides playback illumination for the display hologram pursuant to diffraction of an off-axis playback beam that does not have the predetermined wavefront configuration, and wherein the playback illumination provided by the light configuring hologram has the predetermined wavefront configuration.

Abstract: An optical parking alignment system that includes at least one projector located on a vehicle for projecting a respective image forwardly of the vehicle, whereby alignment of the vehicle is indicated when each respective image is in focus on a screen disposed in front of the vehicle. The projector cam comprise a transparency and an imaging lens, or a hologram and a narrowband light source.

Abstract: A hologram decal including a hologram layer having first and second surfaces, a first polymer layer secured to the first hologram surface, a second polymer layer secured to the second hologram surface, a pressure sensitive adhesive layer disposed on the non-hologram side of one of the first and second polymer layers, and a release liner covering said pressure sensitive adhesive layer, and techniques for making the hologram decal.

Abstract: A hologram structure for use in a holographic center high mounted stoplight system for a vehicle. The hologram structure includes a hologram layer having a plurality of holographic lenses formed therein, each holographic lens being configured to diffract light into a predetermined solid angular region.

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.

Abstract: A hologram decal including a hologram layer having first and second surfaces, a first polymer layer secured to the first hologram surface, a second polymer layer secured to the second hologram surface, a pressure sensitive adhesive layer disposed on the non-hologram side of one of the first and second polymer layers, and a release liner covering said pressure sensitive adhesive layer, and techniques for making the hologram decal.

Abstract: A holographic recording medium is treated to reduce or eliminate unwanted extraneous diffraction in a volume transmission hologram. Surface regions of the medium are desensitized either before or after a holographic recording to reduce the contrast of the holographic fringe pattern along the surfaces, and thereby to eliminate planar phase grating effects. Treatments include applying a burst of gas or vapor to the surface, irradiating the surfaces with highly absorbed incoherent light, thermally treating the recording medium.

Abstract: Multiple layers or holographic exposures and methods for preparing multiple layers of holographic exposures are described. The multiple layers of holographic exposure combine to form holographic stacks and are fabricated from layers of exposed and processed photosensitive recording films, each of which has at least one independently recorded hologram. The holographic stacks are useful for providing wide bandwidth holograms and holograms having superimposed images.

Abstract: A method for precisely controlling the overall average diffraction efficiency of a hologram including the steps of (a) providing a hologram layer that includes a hologram formed pursuant to hologram forming exposure and development, (b) coating the hologram layer with a photoresist layer, (c) masking the photoresist layer with a mask having opaque and transparent areas wherein the proportion of the opaque areas relative to the transparent areas is selected pursuant to the desired diffraction efficiency, the opaque and transparent areas being sufficiently small so as to have little noticeable effect when the resulting hologram is played back, (d) exposing the photoresist layer to actinic illumination through the mask transparent areas, (e) developing the photoresist layer to remove the photoresist in the areas illuminated by the actinic illumination to uncover the areas of the recording material corresponding to the transparent areas of the mask, (f) etching the recording material to remove the areas thereof t