Abstract: An optical recording method includes providing an optical recording medium capable of forming both a refractive index grating and an absorption grating by light irradiation; Fourier transforming with the same lens a signal beam that represents binary digital data with a brightness image and a reference beam such that they are focused at a point outside the optical recording medium; irradiating the Fourier transformed signal beam and reference beam simultaneously onto the optical recording medium and forming a diffraction grating at the optical recording medium according to an interference fringe between the signal beam and the reference beam, or according to an interference fringe within the signal beam itself, and recording the signal beam as a hologram.

Abstract: An acoustical holographic imaging method and apparatus for introducing a reference wave into a hologram surface such that the reference wave does not interfere with an object placed adjacent to or in close proximity to the hologram surface. More particularly, the ultrasonic holographic imaging system may use a reference wave introduced on the side of a thin (3 element) detector that acts as a wave guide; to introduce the reference wave to a liquid-to-gas interface or alternatively, from the topside of the detecting surface through a liquid-to-liquid interface. The system eliminates the acoustic lens system, thereby reducing the size and cost of the system. Further, an object may be placed at the detecting surface, increasing the depth of field of the resultant image and reducing the energy needed from the object source. The system may additionally utilize multiple reference sources.

Abstract: A diffuse reflector comprises a substrate (20) having an asymmetric, reflective, periodic surface relief microstructure formed such that, under illumination by a multiplicity of wavelengths in a plane of incidence or illumination lying along the axis of asymmetry, substantially all the said wavelengths are preferentially scattered or guided into a single, common viewing zone offset from the direction of specular reflection hereinebefore defined.

Abstract: A method of generating a Computer Generated Hologram (CGH) using the diffraction specific algorithm allows a curved wavefront to be produced from a single hogel, rather than the planar waves of the prior art. This allows a wavefront from a singel hogel to generate a point in the image volume. An imaginary wavefront is transmitted from each point in the image volume and sampled at a plurality of points over the hogel. These samples are used to produce a set of complex Fourier coefficients that can be used to approximate the original waveform.

Abstract: An independent mouse or trackball device assembly uses a keyboard as an operational relay providing for the wired or wireless coupling of the mouse or trackball device to the keyboard assembly.

Abstract: A holographic storage apparatus for recording data in a holographic medium includes at least one light source for generating a reference beam and a signal beam. The reference beam is preferably a phase beam of unchanging phase content. The apparatus also includes a holographic medium placed in a path of the reference beam and a path of the signal beam. The holographic medium has a first face and both the reference beam and the signal beam enter the holographic medium through the first face. The holographic medium also includes a data reflective surface. The reference beam and the signal beam interfere in the holographic medium to create a hologram only after at least one of the reference beam and the signal beam have reflected off of the data reflective surface.

Abstract: The present invention relates to systems and methods for managing images and related information. In one implementation, geographic information system (GIS) layer information is registered or aligned to an image using digital watermark information embedded within the image.

Abstract: In an example holographic data storage medium, which has a polymer film which serves as a storage layer and can be changed locally by heating, the polymer film is set up as a top layer of the data storage medium. Arranged underneath the polymer film is an absorber layer which has an absorber dye. The absorber dye is set up to at least partly absorb a write beam serving to put information in and to discharge the heat produced in the process at least partly locally to the polymer film. In an advantageous refinement of the example data storage medium, there is an adhesive layer underneath the absorber layer and a partly transparent reflective layer between the polymer film and the absorber layer.

Abstract: A mirror angle measurement and a servo control apparatus for a Holographic Digital Data Storage (HDDS) system is disclosed. The mirror angle measurement apparatus includes a first mirror having a first reflecting surface by which the reference beam is reflected toward the holographic medium, and a second reflecting surface by which a control beam is reflected to adjust the incident angle of the reference beam; a transmission unit for causing control beam to the second reflecting surface; a second mirror for returning the control beam to the second reflecting surface; and a photo detector unit for detecting the amounts of the control beam. The angle of the first mirror is adjusted based on a comparison result between the amounts of the control beam detected by the photo detector unit.

Abstract: A method, apparatus, and system provide the ability for storing holograms at high speed. A single laser diode emits a collimated laser beam to both write to and read from a photorefractice crystal. One or more liquid crystal beam steering spatial light modulators (BSSLMs) or Micro-Electro-Mechanical Systems (MEMS) mirrors steer a reference beam, split from the collimated laser beam, at high speed to the photorefractive crystal.

Abstract: A recording medium including a storage part to hold a medium identifier intrinsic to each recording medium, and a hologram generated using a reference beam modulated with the medium identifier. Preferably, the hologram is fixed on a surface of the recording medium.

Abstract: The present invention provides a multi-channel tunable filter and methods for making such a filter. In one embodiment, the filter comprises a bank of gratings imprinted into a filter material, such as Lithium Niobate. In another embodiment, the filter comprises a bank of gratings imprinted on a thin-film filter. An optical read-head comprising a pair of lenses is configured to pass light from within an optical fiber carrying multiple wavelengths through an appropriate grating to extract or drop a specific wavelength. To ensure continuous data transmission, the filter is tuned to a wavelength by configuring the read-head to move in a hitless manner. In one embodiment, the gratings are recorded by the interference of two beams. A first plane wave reflects off a first mirror stack and a second plane wave reflects off a second mirror stack. In another embodiment, the gratings are recorded by a phase masking method.

Abstract: An electro-holographic lens device comprising: an active layer made from a transparent photo-refractive material, whose refractive index may be locally modified by locally applying an electric field; an array of electrodes in a predetermined density, provided adjacent the active layer for locally providing electric fields across an array of predetermined locations in the active layer; and a control unit for applying and controlling application of electric fields in a dynamically controllable predetermined locations for creating a holographic fringe pattern across the active layer.

Abstract: The present invention provides a method and apparatus for a multilayer optical articles. A method comprises forming a first multilayer article with a first substrate and a second substrate with a first adherent disposed between the first and second substrate. A first surface of a third substrate is then grasped with a first holder and a second adherent is then disposed on one or more surfaces selected from a second surface of the third substrate and a surface of the first multilayer article while the multilayer article is grasped by a second holder. The second adherent is then at least partially cured while the first and second holders maintain their grasp and while the inner surfaces of the first and second holders are in the selected angular relationship to form a second multilayer article.

Abstract: A temperature compensated apparatus for filtering light is comprised of a holographically recorded grating defined in a photosensitive layer for providing optical filtration for light incident on the grating with a predetermined angle of incidence, and an angulation means responsive to temperature for tilting the grating relative to the angle of incidence of the light as a function of temperature of the grating so that changes in the filtration by the grating compensate for changes in temperature of the grating to maintain effective filtration of the light approximately constant.

Abstract: A method for impressing holographic images or holograms in the surface of metal objects such as aluminum cans, sheet metal or metal foil. The surfaces of metal shims and print rolls bearing holograms are hardened as by coating them with thin amorphous diamond coatings or diamond like coatings so the holograms can be embossed into many thousands of metal objects with clarity and consistency.

Abstract: An optical pickup apparatus having laser light sources emit a first light beam having a relatively shorter wavelength for a DVD and a second light beam having a longer wavelength for a CD-R, an objective lens having a focal length of an information recording surface in the DVD, an optical path control unit controls the light beams so that the light beam emitted from one of the laser light sources is directed to the objective lens and the light output from the objective lens is directed to the optical detection unit, and a phase shift unit between the optical path control unit and the objective lens and which shifts a phase of the second light to reduce the size of a beam spot which is formed the information recording surface in the CD-R.

Abstract: A reconfigurable optical add/drop module (ROADM) for dynamically adding or dropping various wavelengths of an optical signal without having to physically replace the module with a wavelength-specific add/drop module, and corresponding methods. A multiplexed optical signal in an optical network enters the reconfigurable optical add/drop module. Filters on the module separate various wavelengths of the optical signal along the module's various waveguides and a reconfigurable switching matrix directs the various wavelengths of the optical signal to be added, dropped and/or combined with other wavelengths.

Abstract: To reduce the cost while maintaining the real time environment in receiving ultrasonic waves in an ultrasonic receiving apparatus which is capable of reducing changes in detection sensitivity due to environmental changes in the ultrasonic detecting element. The ultrasonic receiving apparatus comprises a light source for generating broadband light, an ultrasonic detecting element including an ultrasonic sensing portion that expands and contracts in response to a received ultrasonic wave and has optical reflectance that changes in accordance with expansion and contraction thereby performing intensity modulation on the light, spectrum-separating means for spectrum-separating the light, first photo-detecting means having a plurality of photoelectric conversion elements for detecting the light for plural wavelength components, and second photo-detecting means for detecting a selected wavelength component included in the light on the basis of a detection result of the first photo-detecting means.

Abstract: The present invention relates to a method for producing an optical recording medium. In the method, on the surface of a recording layer formed by spin-coating a first coating solution containing a photo-isomerizable component, a second coating solution that contains a photo-isomerizable component that can be isomerized by radiation having the same wavelength as radiation used for isomerizing the photo-isomerizable component contained in the recording layer and incapable of dissolving the recording layer is spin-coated to form an intermediate layer. Since the intermediate layer thus formed cannot be dissolved by the first coating solution, a recording layer is further laminated on this layer. Thus, it becomes possible to make the recording layer thicker and also to provide a high-density recording characteristic.

Abstract: A band-pass filter has a reflecting optical element having a fixed reflection angle selection region for wavelengths of a given region, and has an optical path such that reflection is performed at least once and transmission is performed at least once at the reflecting optical element.

Abstract: A security document, such as a banknote, includes an optical security area having a first periodic optical structure and a security sign provided on the security area and configured to circumscribe a second periodic optical structure which is disposed in offset relationship to the first periodic optical structure. Arranged on the security area is a see-through element for enhancing recognizability of the security sign on the security area. The see-through element defines hereby a viewing zone which covers part of the security sign so as to render this part of the security sign visible by the naked eye.

Abstract: A volume hologram for modifying a characteristic of an input microwave beam and a method for manufacturing thereof are disclosed. The hologram is fabricated from a multi-layer artificial dielectric wherein each layer is made of a dielectric material and includes a lattice of inclusions, for example metal disks disposed on one side thereof, and wherein a pre-determined three-dimensional grating pattern of dielectric perturbations is induced by spatial modulating the lattice of the inclusions. The hologram can be designed for efficiently steering, reshaping, combining or splitting microwave beams.

Abstract: An optical pickup apparatus having laser light sources emit a first light beam having a relatively shorter wavelength for a DVD and a second light beam having a longer wavelength for a CD-R, an objective lens having a focal length of an information recording surface in the DVD, an optical path control unit controls the light beams so that the light beam emitted from one of the laser light sources is directed to the objective lens and the light output from the objective lens is directed to the optical detection unit, and a phase shift unit between the optical path control unit and the objective lens and which shifts a phase of the second light to reduce the size of a beam spot which is formed the information recording surface in the CD-R.

Abstract: A holographic ROM system includes an alignment apparatus for aligning a holographic medium for storing data and a mask with patterns of the data. The alignment apparatus has a beam irradiating unit for irradiating a light beam to alignment marks of the holographic medium and the mask; an alignment mechanism for moving at least one of the holographic medium and the mask in response to a control signal; a photo detecting unit for detecting the beam passing through the alignment marks of the holographic medium and the mask while the holographic medium and/or the mask being moved; and a control unit for generating the control signal, the control unit controlling the alignment mechanism based on intensity of the beam detected by the photo detecting unit.

Abstract: The invention relates to a holographic viewing device that enables a given pattern to be properly viewed in place of light sources in a scene and is easy to fabricate and assemble with consistent characteristics, and a computer-generated hologram for the same. The invention provides a holographic viewing device in which computer-generated holograms 2 and 3 each constructed as a transmission Fourier transform hologram is fitted in a frame member 1. At least one of phase information and amplitude information recorded in a certain predetermined peripheral site of the computer-generated hologram 2, 3 relative to an input pattern reconstructible from the computer-generated hologram is removed.

Abstract: An image detected by a CCD image sensor 108 when only a non-modulated signal light is applied to a holographic memory 120 in which data is not recorded is ensured as a noise pattern. When data is reproduced, the previously obtained noise pattern is subtracted from a reproduced image detected by the CCD image sensor 108.

Abstract: A recording material for holograms includes a metal oxide porous body with an oxygen donor substance in the pores. In addition, a method manufactures a recording material for holograms that include a metal oxide porous body with an oxygen donor substance in the pores. The method includes forming a metal oxide porous body from a metal oxide precursor, and supplying an oxygen donor substance to the pores of the metal oxide porous body.

Abstract: The invention relates to a hologram carrier having a hologram surface and a reference surface to facilitate the acquisition of the hologram surface by a device. In this case, provision is made for the reference surface to comprise at least one step, which is arranged to interengage with a complementary formation on the device in order to align said device.

Abstract: A method for monitoring diffraction while recording a hologram includes: generating a source beam; generating a data beam by projecting a first component of the source beam through a data source, the data beam having a first polarization; generating a reference beam by adjusting a polarization of a second component of the source beam to provide a second polarization; recording a hologram in a holographic medium from an interference between the data beam and the reference beam; and measuring an offset component in an output arm of the data beam.

Abstract: A hologram screen 1 displays an image by diffracting and scattering image light 31 projected from an image projection apparatus 2. An upward/downward light scattering device 13, which scatters light incident from an upward/downward specific angle range spreading obliquely upward or downward, is placed on the image projection apparatus side of a hologram device 12 in the hologram screen 1. A leftward/rightward light scattering device 14, which scatters light incident from a leftward/rightward specific angle range spreading obliquely leftward and rightward, is placed between the hologram device 12 and the scattering device 13. The construction is such that the upward/downward specific angle range contains the incidence angle of the image light 31 on the hologram screen 1, and thus provides a hologram screen having good color reproducibility and which permits viewing of the background.

Abstract: A holographic imaging system and method includes a radiation source for generating radiation. A data base has a set of elements, each element is indicative of a trajectory of a light ray exiting a point in a recorded scene. A spatial light modulator is receptive of the radiation from the radiation source and the elements of the data base mapped to the spatial light modulator, thereby projecting from the spatial light modulator an optical signal in the nature of a two dimensional bitmap of the recorded scene. A diffractive optical element includes a set of basis fringes receptive of the projected optical signal from the spatial light modulator for diffracting the optical signal in a specified direction. A multiplexer is receptive of the elements of the data base for multiplexing the elements of the data base to the spatial light modulator. A timing device synchronizes multiplexing the elements of the data base to the spatial light modulator and diffracting the optical signal in a specified direction.

Abstract: A holographic screen for displaying images by diffracting and dispersing an image beam projected by an image projector comprises a main hologram for diffracting and dispersing an incident image beam from one of an upward angle and a downward angle, and a directional dispersion hologram, disposed on an image projector side of the main hologram, for dispersing and transmitting part of the image beam within a predetermined angle range centered on a direction of incidence thereof, and directly transmitting another part of the image beam, thereby providing a holographic screen that can maintain the brightness and improve the color reproducibility of a displayed image.

Abstract: A holographic storage apparatus for recording data in a holographic medium includes at least one light source for generating a reference beam and a signal beam. The reference beam is preferably a phase beam of unchanging phase content. The apparatus also includes a holographic medium placed in a path of the reference beam and a path of the signal beam. The holographic medium has a first face and both the reference beam and the signal beam enter the holographic medium through the first face. The holographic medium also includes a data reflective surface. The reference beam and the signal beam interfere in the holographic medium to create a hologram only after at least one of the reference beam and the signal beam have reflected off of the data reflective surface.

Abstract: A distributed system for producing holographic stereograms (holograms). A data acquisition station is typically remote from image processing, printing, and replicating stations. The data acquisition station is designed to maximize customer convenience, and may be the customer's own personal computer. The data acquisition station is further designed to accept a wide variety of source data and to perform whatever processing is required to deliver image data to the image processing station in an acceptable format. The data acquisition station further has processing capability to display preview images, which may be assembled by programming executing at the data acquisition station or downloaded from a server.

Abstract: In accordance with teachings of the present invention, a device accomplishes the task of reducing or preventing reflections of the reference beam off a diffuser from striking the holographic recording material. First, the device absorbs a large percentage of the reference beam power so that portion of the reference beam never reaches the diffuser. Second, the device blocks the small amount of reference beam that is incident on the diffuser and reflects back toward the film. Thus, the proposed device operates as an absorber-blocker (AB) for the reference beam.

Abstract: The invention relates to a holographic viewing device that enables a bright reconstructed pattern to be viewed in place of light sources in a scene while a spot due to zero-order transmitted light is kept unnoticeable, and a computer-generated hologram for the same. The invention provides a holographic viewing device comprising a frame and a computer-generated hologram fitted in the frame. The computer-generated hologram is constructed as a transmission Fourier transform hologram.

Abstract: An image projection system capable of projecting images to multiple screens or viewing surfaces. The system uses a moveable mirror to direct the projected images to the screens. The moveable mirror may work in concert with one or more fixed mirrors to reflect the projected images to screens in a variety of configurations relative to the projector.

Abstract: In one embodiment, holographic data storage medium includes a first thermoplastic substrate portion having a thickness less than approximately 2 millimeters and a second thermoplastic substrate portion having a thickness less than approximately 2 millimeters. A holographic recording material may be sandwiched between the first and second thermoplastic substrate portions. By making thermoplastic substrate portions sufficiently thin, edge wedge problems can be avoided.

Abstract: In a storing mode of an apparatus for storing and retrieving a sequence of digital page data, a first/second complex reference beam and a modulated signal beam converge on a storing location to generate a sequence of first/second interference patterns to be sequentially stored on a holographic medium. A shift selectivity of the first complex reference beam is larger than that of the second complex reference beam so that the second interference pattern is used as a servo pattern to sequentially determine where the first interference patterns have been stored.

Abstract: There are provided a hologram laminate and a hologram label which do not involve any problem in the production process per se of forging preventive labels using a volume hologram, can provide a reliable process of the attainment of forgery preventive effect, and can make difficult to notice the signs of the forgery preventive processing. In applying a protective film 108 onto a hologram 107 through a second pressure-sensitive adhesive 109, the adhesive strength is partially varied. By virtue of this construction, upon separation of the protective film 108, the second pressure-sensitive adhesive 109 is partially left on the hologram 107, so that the fact of the separation can be found out.

Abstract: An optical add/drop filter is formed using a hologram which is tuned to a wavelength in an optical signal. The diffraction condition of the hologram may be varied to vary the in add or drop content.

Abstract: In a storing mode of an apparatus for sequentially storing and retrieving digital page data, a first and second complex reference beams and a modulated and second signal beams converge on a first/second location to generate a sequence of first and second interference patterns to be sequentially stored on a holographic medium. A shift selectivity of the first complex reference beam is larger than that of the second complex reference beam so that the second interference pattern is used as a servo pattern to sequentially determine where the first interference patterns have been stored.

Abstract: A rain sensor for a motor vehicle, having a transmitter emitting radiation, a receiver, and a holographically embodied diffractive element that has a linear-grating-like structure.

Abstract: The invention provides a hologram plate which is used with the double-focus replication process, and which is integrated with a spacer to impart marring resistance thereto, and is integrated with a light absorbing layer to allow zero-order light and first-order light to have substantially the same intensity. This hologram plate 42 comprises an array of collective element holograms for diffracting parallel light incident thereon at a specific wavelength and a specific incident angle in such a way that the light is converged onto a specific focal length position. The hologram plate 42 is a multilayer structure made up of a first transparent substrate 31, a hologram layer 32, an adhesive layer 33 and a second transparent substrate 41. The second transparent substrate 42 defines a surface in contact with a hologram photosensitive material 53 during hologram replication.

Abstract: The invention relates to an optical element with variable optical properties, which ensures that the amount of light available is increased, and an optical device using the same. In a liquid crystal variable hologram element 3, polymer layers 18 and liquid crystal layers 19 are alternately arranged between transparent substrates 16 and 17, with liquid crystal particles 20 lining up in each liquid crystal layer 19. When voltages are applied on transparent electrodes 21 and 22, liquid crystal molecules 23 have their longitudinal directions oriented vertically with respect to the electrodes, so that the refractive index of the polymer layers 18 is substantially equal to that of the liquid crystal layers 19, resulting in no development of hologram. When the voltages are held off, the refractive index of the polymer layers 18 is different from that of the liquid crystal layers 19. This repetition gives rise to an interference fringe action, by which a hologram can be developed.

Abstract: The present invention provides a hologram screen which is capable of preventing separation, and damage to, a hologram film and which permits the hologram film to be reused easily. The present invention relates to a hologram screen that is comprised of a hologram film having the function of diffracting the light projected from a projector, and first and second transparent members that together sandwich the hologram film from the front and back surfaces thereof so as to cover the same.

Abstract: The present invention provides a multi-channel tunable filter and methods for making such a filter. In one embodiment, the filter comprises a bank of gratings imprinted into a filter material, such as Lithium Niobate. In another embodiment, the filter comprises a bank of gratings imprinted on a thin-film filter. An optical read-head comprising a pair of lenses is configured to pass light from within an optical fiber carrying multiple wavelengths through an appropriate grating to extract or drop a specific wavelength. To ensure continuous data transmission, the filter is tuned to a wavelength by configuring the read-head to move in a hitless manner. In one embodiment, the gratings are recorded by the interference of two beams. A first plane wave reflects off a first mirror stack and a second plane wave reflects off a second mirror stack. In another embodiment, the gratings are recorded by a phase masking method.

Abstract: An interior rearview mirror assembly suitable for use in a vehicle includes a variable reflectance reflective element, which includes an electrochromic medium, a first information display positioned to the rear of the variable reflectance reflective element, and a second information display. The mirror assembly further includes a single control for adjusting the luminous intensity of the first information display and the second information display and at least one light sensor, with the output of the control being generated responsive to a light level sensed by the at least one light sensor. In addition, the luminous intensity of the first information display and of the second information display increases responsive to the output of the control to compensate for any decrease in transmission of the electrochromic medium.

Abstract: The invention relates to a holographic viewing device that has a high diffraction efficiency, enables bright patterns with less noticeable conjugate or higher-order images to be viewed in place of light sources in a scene and is easy to fabricate with consistent characteristics. The holographic viewing device comprises a frame and a computer-generated hologram constructed as a transmission Fourier transform hologram and fitted in the frame. The computer-generated hologram 20 comprises minuscule cells having pitches &dgr;x and &dgr;y, with a reconstruction image area 30 defined by a range of spreading of ± first-order diffracted light of given wavelength from a diffraction grating having grating pitches 2&dgr;x and 2&dgr;y that are twice as large as the pitches of cells, and an input image pattern, reconstructed at that wavelength in a range of up to ⅔ of the reconstruction image area 30, is recorded in the computer-generated hologram.