Abstract: A transmission holographic element (30) comprises a holographic material (330) deposited onto a substrate (31) to form a composite substrate structure. The substrate (31) is coated with a mirror coating (32) prior to the deposit of the holographic material (33) which is reflecting at the reading wavelength and non-reflecting at the recording wavelength. This allows the use of substrates that need not be of good optical quality because when the holographic element is exposed to light at the reading wavelength, light is reflected by the mirror coating before passing through the substrate. In addition, the mirror coating is protectred from damage during processing since it is between the substrate (31) and holographic material (33).

Abstract: A programmable optical interconnection apparatus and method in which a plurality of spatial light modulators (SLM) form a plurality of spatially modulated beams from a data signal. A hologram is responsive to the spatially modulated beams for generating at least two destructively interfering coherent beams at a first optical detector to thereby disconnect the data signal therefrom, and for simultaneously generating at least two constructively interfering coherent beams at a second optical detector to thereby connect the data signal beam thereto. The hologram is preferably a computer generated thin hologram which does not rely on Bragg diffraction. A low cost, high density, high efficiency programmable optical interconnect is thereby provided.

Abstract: A decorative substrate consisting of a paper base sheet coated with a thermoplastic material, involving a novel technique for coating and embossing the substrate. The paper sheeting is supplied with a thermoplastic material, as by coating or extrusion. The coated sheet is heated to adequately soften the coating, such as by use of a heated cylinder, and remote heat sources such as infrared heaters. The softened sheet surface is then decorated using an embossing member, to provide a diffraction pattern or hologram. Use of an embossment pattern of lesser depth than the surface roughness of the sheet before embossing provides attractive decorative patterns.

Abstract: A hologram scale is comprised of a hologram grating plate in which a hologram grating is formed, and a protecting substrate on which an origin and/or fixed point detecting scale of the hologram grating is formed, wherein the protecting substrate is bonded to the hologram grating plate so as to cover the hologram grating plate at its surface on which the hologram grating is formed. Also, a hologram scale is comprised of a hologram grating plate in which a hologram grating is formed, an origin and/or fixed point detecting scale substrate on which an origin and/or fixed point detecting scale of the hologram grating is formed, and a protecting substrate to which the hologram grating plate and the origin and/or fixed point detecting scale substrate are both bonded.

Abstract: First and second coherent beams illuminate a common area on an exposure station. A phase detector senses the relative phase between the first and second beams to provide a control signal. There is at least one phase shifter in the path of at least one of the coherent beams. The control signal is coupled to the phase shifter to adjust the phase imparted thereby so that the relative phase between the first and second coherent beams is substantially constant.

Abstract: An article has a light-transparent visual display feature through which a graphic design or a solid object can be seen, the light-transparent visual display feature is a light-transparent film sheet which contains a Lippman-Bragg reflection hologram which has a viewing angle of not more than 20.degree. on either side of a selected viewing axis or axes and a depth of holographic image which is not more than 5 mm on one side or the other of the image plane. When the article is a package, the restricted view is provided around a vertical axis relative to the observer so that as an observer passes the illuminated package laterally witth the hologram on the vertical face, the hologram will suddenly come into view and just as suddenly slip from view as viewing angle is passed. When the article is an identification or credit card, the transparent film material bearing the hologram is laminated to the top surface of the card which bears a graphic design relevant to the holder of the card.

Abstract: Holographic optical elements relatively free of unwanted, secondary fringes are produced using light having a limited coherence. A photosensitive material of a predetermined thickness records the interference between two beams of light. The mutual coherence of the two illumination beams is sufficiently great to form high contrast interference fringes within some portion of the photosensitive medium. The mutual coherence is limited to prevent the formation of high contrast interference with reflections from the various parts of the construction optics. The two illumination beams may be incident from opposite sides of the photosensitive medium forming a reflection holographic optical element or from the same side of the photosensitive medium forming a transmission holographic optical element. A laser generates the first illumination beam. Control of the mutual coherence may be by passing the first illumination beam through a moving diffuser plate or by varying the wavelength of the laser during the exposure.

Abstract: A three-step process is combined with an edge-lit system to provide a self-contained, maximally-compact holographic display. In one embodiment, a hologram is affixed to an upstanding transparent support plate mounted through the top of a housing in which the hologram is edge-illuminated with white light from a source in the housing immediately beneath the plate to generate brilliant, sharp and deep multi-color images which straddle the hologram plane. In another embodiment, the transparent support plate is mounted in a frame which carries the edge-illumination source. All displays may either be free-standing or wall-mounted, as desired.

Abstract: Improved optical holographic apparatuses are disclosed for making white light viewable rainbow holograms in one step utilizing concave mirror optics. On-axis and off-axis configurations are presented for holography of real objects and for reduced image holography of a real image projection from a laser transmission hologram. An optical apparatus and curved recording devices are devised to reduce and/or eliminate certain aberrations introduced by the concave mirror. To yield a wide holographic field of view at low cost, small diameter mirrors are employed in two alternative devices for replacing a single concave mirror in the various embodiments. Two methods are then presented to obtain reduced image size one-step rainbow holograms from a full size object or holographic image.

Abstract: This invention relates to a method and apparatus for exposing a photosensitive film on a holographic plate to fabricate a reflective holographic optical element. The apparatus incorporates compensating means which are adapted to compensate for the effects of refractive index shift of the film due to refractive index variations during the exposure process. In one form of the apparatus, a hologram-mirror arrangement is placed on a table on an accurately controlled stepper motor rotating stage so that the table is progressively tilted. In an alternative arrangement the angle of the exposing radiation beam is changed and directed on to the stationary hologram-mirror arrangement. Where a tuneable holographic filter is required where the exposure angle varies over the hologram aperture angular shift is achieved by simple lateral and linear shift of the hologram. The compensating means can also comprise an arrangement for progressively changing the wavelength of the exposing radiation beam.

Abstract: Highlighting a selected area of a holographic display indirectly by selectively repositioning a small lens within the hologram illumination beam.

Abstract: A holographic stoplight for a vehicle including a stoplight hologram, a source of playback illumination, and a transparent prism for supporting the stoplight hologram and for guiding the playback illumination to the stoplight hologram. The prism with the stoplight hologram is mounted in front of the rear window of a vehicle with the light source beneath the surface of the rear panel that is adjacent the rear window.

Abstract: The present invention comprises hologram combiners that incorporate one of several compositions of material to seal their perimeters and prevent the hologram from being attacked by water. The design of the combiner edge seals are fabricated using a perimeter edge buildup technique. The invention is implemented by the use of a band of polymer film, or a metal film such as aluminum foil, for example, that is adhered to the edge of periphery of the combiner. Adhesion is achieved by the use of a adhesive material that has been filled with a water absorbing material comprising molecular sieves such as crystalline aluminosilicate, zeolites, or calcium oxide. Calculations and accelerated static testing have indicated that the present invention provides for a hologram combiner that meets the most stringent environmental requirements, and is suitable for substantially all applications in which it may be employed.

Abstract: A fundamental method and apparatus for using wave-type energy, such as light, to provide: amplification, energy control, and logic functions including OR, EXCLUSIVE OR, and INVERTER; as well as: bistable information storage; computing; visual display; and dynamic imaging (where images are modified continually as computation proceeds) is disclosed. The method uses modulated input beams that are able to produce interference fringes, that are separated into constructive interference component regions and destructive interference component regions, to provide outputs from individual functions, that result from the interference which occurs in the separated interference-fringe component regions. Many basic functions are interconnected to produce more complex functions including complete digital and analog computers. Holograms made up of many subholograms are used to separate fringe component regions, and to direct function interconnecting beams.

Abstract: A laser light show device and method produces a surface projected or suspended holographic image, and includes multiple image projectors. One image projector provides the object image information representing the primary subject. For surface projections, additional background image projectors provide background image information generated using a wobbler plate-reflected beam diffracted through a spherical lens, a beam unidimensionally diffracted through a rotating cylindrical amorphic dipolyhedral lens, and a beam diffracted through multiple diffraction gratings. A suspended holographic image is produced by parabolically focusing multiple images projected onto a spherical image screen.

Abstract: Electrolessly deposited metal holograms comprising a polymeric substrate having a holographic relief-patterned surface and a metal reflective layer electrolessly deposited to conform to and reproduce the holographic relief patterned. Light incident to the metal surface is reflected to provide an holographic reproduction of an holographic image inherent in said relief-patterned polymeric substrate.

Abstract: A method and system for replicating microstructure surface relief patterns, such as diffraction patterns including holograms, by casting. A liquid casting resin is held between a surface relief master of the microstructure to be replicated and a substrate while the resin is hardened by actinic radiation curing. Application of resin to edges and discontinuities of the master is avoided in order to reduce undesirable build-up of resin on these areas of the master. The hardened resin surface relief replica may optionally be coated with a discontinuous graphical pattern of a clear or colored paint that eliminates the effect of the surface relief pattern in the regions so coated.

Abstract: An apparatus for recording Lippman holographic mirrors comprises an exposing volume optically coupled on one side with an index-matching fluid to the holographic material to be recorded. The volume is exposed on an adjacent side to a light beam expanded in one direction into a plane of light whose projection on the volume is a line. The line of light and the holographic material are moved relative to each other on an interrupted or a continuous basis to expose the holographic material.

Abstract: A holographic method of the type implementing a conoscopic system including a birefrigent crystal inserted between two polarizers and a photosensitive element, wherein the method includes a step consisting in inserting one-dimensional optical means on the path of the light rays such that the conoscopic system only collects light that is parallel or quasi-parallel to a plane including the axis of the conoscopic system. The invention also provides apparatus for implementing the method.

Abstract: A holographic apparatus of the type comprising a conoscopic system including a birefringent crystal inserted between two polarizers, wherein the apparatus also includes an aperture angle limiter inserted on the path of the light rays and wherein one of the birefringent crystal and the aperture angle limiter is disposed off the optical axis of the apparatus.

Abstract: An apparatus for interfacing holographic and electronic data comprises an input/output port for the interfacing of a holographic wavefront interference pattern and an electronic array capable of producing digital electronic information from a holographic wavefront input and for converting electronic information into holographic information using optical fibers, sensors, and optical switches. In one embodiment a plurality of optical fibers having a small end and a large tapered end are operably combined with a plurality of optical sensors wherein each of said optical sensors provide a digital signal of 1 if lit and a digital signal of 0 if unlit.

Abstract: Respective processors for pairs of photodetecting elements are included in an imager used for sensing hologram fringe patterns in an optical interferometer. These processors remove the direct-current pedestal from in-phase and quadrature-phase field images, then perform partial correlations of the resulting field images on a pixel-by-pixel basis, and then sum the partial correlations to complete the image correlation process and to provide imager output signal or the basis therefor. This localized processing greatly reduces the number of samples that have to be brought out of the imager each frame when the imager is used in an optical interferometer to detect phase modulation in an optical signal, allowing for increased frame rates in accordance with a further aspect of the invention. Image correlation is done according to a novel algorithm that avoids actually having to multiply together correspondingly located pixels in each pair of successive fields forming a successive non-overlapping frame.

Abstract: This invention is an optical printer that translates and records visual information that can be seen with ambient light in the first generation holographic printing. The invention permits recording of the information to be made into the light sensitive emulsion as a relief. The result is a stereo-optical, multichannel holographic recording of said information. Applications of the invention may include the commercial photography industry, cinematography, medical, passports, drivers' licenses, security entrance control systems, military, point of purchase advertising, publishing and security as well as other uses connected with all relevant existing holographic technology.

Abstract: A holographic system which contains a multiple image hologram comprised of two or more images at varying focal distances, which when viewed consecutively and in repetition will exercise the ciliary muscle of the eyes. The holographic system will have its own power to illuminate said hologram. The shifting of conditions of the viewer to alternate the viewing of one image and then the other, may involve the physical movement of the user's head, or the system may contain a motor coupled to rotate said system. The system may include a clock-timer to activate said motor, and for periodically illuminating the hologram. The system may include a sound alarm to remind the viewer to utilize the holographic system.