Abstract: The invention relates to a color hologram display an image of a three-dimensional object and a hologram image of a pattern of plane characters, images or the like are recorded in the same volume type hologram photosensitive material in a superposed or multiplexed fashion. A color hologram display 27? comprising a combined reflection and volume type of single layer, wherein a color pattern 29g of plane characters, images or the like and a color three-dimensional subject image O? are reconstructably recorded while spatially superposed one upon another.

Abstract: A security hologram is disclosed that is invisible to a human eye or to various optical detectors until the hologram is optically coupled to a suitable modifier (e.g., a prism). Also disclosed is a method of recording the security hologram and a method of using the hologram in security applications to establish authenticity of article(s).

Abstract: Direct patterning of nanometer scale features by interferometric lithography using a 46.9 nm laser is described. Multiple exposures using a Lloyd's mirror interferometer permitted printing of arrays having 60 nm FWHM features.

Abstract: A holographic printer, a hologram copier and a combined holographic printer and hologram copier system is disclosed. The printer, copier and combined system comprise a pulsed RGB laser system comprising three short cavity oscillators. With the holographic printer digital image data is encoded onto three LCOS reflective SLM displays. The combined holographic printer and hologram copier system comprises a single RGB laser system.

Abstract: A method of recording an exposure pattern in a recording layer of a holographic mask, using an original reticle that has the exposure pattern formed therein, the recording method comprising: illuminating a first recording light and a first reference light to the recording layer simultaneously, the first recording light being illuminated through an original reticle placed opposite to the holographic mask with a first gap therebetween, the first reference light being illuminated to the recording layer at a first incident angle; and illuminating a second recording light and a second reference light to the recording layer simultaneously, the second recording light being illuminated through the original reticle placed opposite to the holographic mask with a second gap therebetween, the second gap being different from the first gap, the second reference light being illuminated to the recording layer at a second incident angle.

Abstract: A method is provided for replicating (copying) a multicolor hologram (e.g., a two-color hologram) into a photosensitive layer by masking to produce a copy (replicate) of the hologram in a manner such that the copy is an accurate and true replication of the hologram (e.g., master hologram) and the copy is characterized to possess a high brightness level and color fidelity comparable to that of the multicolor hologram that was replicated.

Abstract: An apparatus for replicating holographically recorded data, comprising a holographic master media having holographically recorded data thereon; a holographic copy media; a light source for generating a master reference beam and a copy reference beam, coherent with the first object beam, the first master reference beam incident on the holographic master media, the holographic master media diffracting the master reference beam to provide a first object beam; the copy reference beam incident on the holographic copy media; and a first optical relay system, disposed between the holographic master media and the holographic copy media, for relaying the first object beam from the holographic master media to the holographic copy media, the holographic copy media recording an interference pattern between the first object beam and the copy reference beam, thereby replicating at least a portion of holographically recorded data.

Abstract: A recording medium is stacked on a master recording body, to which reference beams are applied each at an incident angle. The interference between diffracted beams diffracted in the data storage sections of the master recording body and the reference beams in the recording medium occurs such that the data are transferred to the recording medium. The use of plural compact light sources for emitting the reference beams allows the recording device to be compact while reducing the power consumption.

Abstract: A single method and apparatus for producing many of the most common types of hologram from digital data is disclosed. The data are generated entirely by a computer as a 3-D (animated) model or from multiple 2-D camera images taken of a real 3-D (moving) object or scene from a plurality of different camera positions. The data are digitally processed and displayed on a small high resolution spatial light modulator (SLM). A compact low energy pulsed laser, is used to record composite holograms. The present invention permits the creation of restricted or full parallax master transmission or reflection type composite holograms, known as H1 holograms, that can be copied using traditional methods. Alternatively the same invention and apparatus permits the direct writing of hologram without the need to pass through the intermediate stage of the H1 transmission hologram.

Abstract: Three-dimensional holographic elements are disclosed. Three-dimensional Bragg gratings recorded on bulks of optical material are included in the disclosure. Such elements may be manufactured by placing a three-dimensional bulk of optical material directly behind a recorded master hologram, directing a reference beam onto a master hologram such that a replica of the master hologram is recorded in the optical material. The replica may form the three-dimensional holographic element. The master hologram may be Bragg grating formed on a surface of a transparent substrate.

Abstract: HROM replication methods, devices or systems are disclosed herein. Also disclosed herein are articles comprising conical reference (reconstruction) beam hologram elements to generate conical or conical like reference (reconstruction) beams which may be used in such HROM replication methods, devices or systems. Further disclosed herein are articles comprising a target medium which may be used in such HROM replication methods, devices or systems.

Abstract: A reproducing apparatus, reproducing method, recording and reproducing apparatus, recording and reproducing method, recording apparatus, and recording method are provided.

Abstract: An apparatus for replicating holographically recorded data, comprising a holographic master media having holographically recorded data thereon; a holographic copy media; a light source for generating a master reference beam and a copy reference beam, coherent with the first object beam, the first master reference beam incident on the holographic master media, the holographic master media diffracting the master reference beam to provide a first object beam; the copy reference beam incident on the holographic copy media; and a first optical relay system, disposed between the holographic master media and the holographic copy media, for relaying the first object beam from the holographic master media to the holographic copy media, the holographic copy media recording an interference pattern between the first object beam and the copy reference beam, thereby replicating at least a portion of holographically recorded data.

Abstract: A method for storing data including: providing a first substrate having a plurality of micro-holograms therein, the micro-holograms being indicative of the data; providing a second hologram-supporting substrate; illuminating the plurality of micro-holograms in the first substrate through the second substrate, thereby producing a holographic pattern in the second substrate indicative of reflections of the plurality of micro-holograms in the first substrate; providing a third hologram-supporting substrate; and, illuminating the holographic pattern in the second substrate through the third substrate, thereby substantially replicating the plurality of micro-holograms in the first substrate in the third substrate.

Abstract: A single method and apparatus for producing many of the most common types of hologram from digital data is disclosed. The data are generated entirely by a computer as a 3-D (animated) model or from multiple 2-D camera images taken of a real 3-D (moving) object or scene from a plurality of different camera positions. The data are digitally processed and displayed on a small high resolution spatial light modulator (SLM). A compact low energy pulsed laser, is used to record composite holograms. The present invention permits the creation of restricted or full parallax master transmission or reflection type composite holograms, known as H1 holograms, that can be copied using traditional methods. Alternatively the same invention and apparatus permits the direct writing of hologram without the need to pass through the intermediate stage of the H1 transmission hologram.

Abstract: A postprocessing apparatus for conducting postprocessing on an image forming member, including a receiving unit for receiving an image forming member having an image formed thereon, and an attaching unit for attaching a hologram recording medium in which a hologram can be written, to the image forming member. The postprocessing apparatus further includes a recording unit for writing related information corresponding to image formed on the image forming member, onto the hologram recording medium.

Abstract: A hologram recording apparatus (100) includes a record angle change device (19) capable of relatively changing the record angle of a hologram recording medium (200) relative to signal light (L3) and reference light (L2); and a control device (18). The control device sets a record angle for recording a specific angle record plane as a standard record angle among a plurality of angle record planes on the hologram recording medium. Furthermore, the control device controls the record angle change device so as to change and fix the record angle after then by a predetermined angle from the set standard record angle.

Abstract: A method of writing a single or double parallax composite 1-step hologram is disclosed. Digital data is acquired from a real or virtual object and is described by a luminous intensity tensor. A single mathematical transformation is performed to convert the luminous intensity tensor into a mask tensor. The single mathematical transformation transforms the digital data whilst integrally correcting the digital data for the finite distortion of an optical objective. Corrected data, described by the mask tensor, is written on to a spatial light modulator. A laser beam is directed on to the spatial light modulator so that at least a portion of the laser beam is spatially modulated to form a spatially modulated laser beam. The spatially modulated laser beam is then passed through an optical objective having a finite distortion and in combination with a reference recording beam forms a composite hologram.

Abstract: A hologram record apparatus (100) includes a parameter set device (19), a move device (20), and a control device (18). The parameter set device (19) modifies parameters for multiple recordings such as a record angle and a focal depth in relation to at least one of signal light (L3) and reference light (L2) and can fix the parameters. The move device (20) relatively moves the focus position of the signal light and the reference light in the direction along the record surface of a hologram record medium. The control device (18) performs control so that the parameter for the last recording used for recording at the m-th focus position is used as the parameter for the first recording at the m+1-th focus position.

Abstract: A planar light source unit includes a light guide plate having an upper surface, a lower surface, and a peripheral edge surface extending between the peripheral edges of the upper and lower surfaces. A part of the peripheral edge surface is a light-receiving surface, and the upper surface is a light-emitting surface. The upper surface of the light guide plate includes an anisotropic diffusion surface and a smooth flat surface.

Abstract: A method of recording an exposure pattern in a recording layer of a holographic mask, using an original reticle that has the exposure pattern formed therein, the recording method comprising: illuminating a first recording light and a first reference light to the recording layer simultaneously, the first recording light being illuminated through an original reticle placed opposite to the holographic mask with a first gap therebetween, the first reference light being illuminated to the recording layer at a first incident angle; and illuminating a second recording light and a second reference light to the recording layer simultaneously, the second recording light being illuminated through the original reticle placed opposite to the holographic mask with a second gap therebetween, the second gap being different from the first gap, the second reference light being illuminated to the recording layer at a second incident angle.

Abstract: A method for aligning an exposure mask, comprises: using a plurality of hologram masks, on which alignment marks are formed,; aligning position of the hologram masks toward an object, which is exposed and on which alignment marks are also formed, a plurality of times by using both alignment marks, wherein a first straight line connects a first area on the object to be exposed for a pattern exposure with the alignment mark for aligning with a holographic mask that is used in an exposure onto the first area and a second straight line connects the other area, adjacent to the first area, on the object to be exposed for a pattern exposure with the other alignment mark for aligning with a holographic mask that is used in an exposure onto the another area, and the first straight line and the second straight line are intersected each other.

Abstract: A method for aligning an exposure mask comprises: using a plurality of hologram masks, on which an alignment mark is formed; aligning position of the hologram masks toward an object to be exposed and on which an alignment mark is also formed, with a plurality of times by using both alignment marks; and pattern-exposing the object, wherein, while aligning at least three consecutive times, an alignment mark for third time aligning on the object is set in between alignment marks respectively for second time aligning and first time aligning, or at a position on an opposite side to a side in which the alignment mark for second time aligning is located with respect to the alignment mark for first time aligning.

Abstract: A method for forming fine concavo-convex patterns by using a relief formation material 3 having a relief formation layer 2 composed of a resin having thermoplasticity and a relief pattern sheet 6 having on a surface thereof fine concavo-convex patterns 5, wherein a photothermal conversion layer 7 is formed in the relief formation material 3 or the relief pattern sheet 6; the photothermal conversion layer 7 is irradiated with light 8 to make the photothermal conversion layer 7 generate heat in the state that the relief formation layer 2 is brought into contact with the fine concavo-convex patterns 5; and the fine concavo-convex patterns 5 are formed on the relief formation layer 2.

Abstract: Information recorded as a hologram in a predetermined position of an optical recording medium is reproduced, and subsequently the reproduced information is re-recorded and retained in the same position as the predetermined position as a hologram. Alternatively, information recorded as a hologram in a predetermined position of an optical recording medium is reproduced, and subsequently the reproduced information is re-recorded and retained in a position different from the predetermined position as a hologram easily.

Abstract: A method of fabricating a hologram having a pattern made up of pixels in which a photosensitive material for forming a hologram is stacked on either a reflection-type hologram or a transmission type hologram. According to one aspect of the invention, the photosensitive material is stacked on a reflection-type relief hologram and reconstructing illumination light of a given wavelength is struck on the reflection-type relief hologram through the photosensitive material, so that interference fringes produced by interference of the light diffracted from the reflection type relief hologram and the incident light are recorded in the photosensitive material.

Abstract: System and method for providing gain and thresholding to a holographic data parallel recording and replication system incorporating independent angular address assignment. A plurality of information bearing light beams in an information bearing light beam arm of a data recording system and a plurality of reference light beams in a reference light beam arm of the data recording system are mutually interfered to store a plurality of spatially separate, spatially modulated light intensity patterns in a holographic data storage medium in a data recording operation. During the data recording operation, the plurality of information bearing light beams are repeatedly circulated through the holographic data storage medium using a resonant cavity formed along the information bearing light beam arm of the holographic recording system.

Abstract: A holographic printer is disclosed which produces an intermediate hologram H3 and uses the intermediate hologram H3 to produce a white light viewable hologram H2.

Abstract: A system and method capable of providing high data rate data copying and recording in holographic data storage while maintaining the copied data's signal-to-noise ratio. This is achieved by using optically-based parallel signal processing. In one preferred embodiment, the present invention uses a plurality of optical resonating cavities to provide thresholding and gain functions via positive feedback.

Abstract: A wavelength multiplexed holographic system includes a wavelength tunable blue-violet laser and a controller for wavelength multiplexing. A method of holographic data recording includes providing a holographic medium, providing a tunable blue-violet laser for wavelength multiplexing, and tuning the laser wavelength to record a hologram at a set wavelength and recording holographic data at the set wavelength on the holographic medium. A method for retrieving holographic data includes providing a holographic medium, providing at least one tunable blue-violet laser, tuning the blue-violet laser to a set wavelength, and retrieving holographic data at the set wavelength.

Abstract: A method of fabricating a holographic mask includes the steps of providing an illumination source and a non-opaque object mask. The source is for generating a coherent illumination beam directed along an axis. The object mask is capable of transmitting a portion of the illumination beam as undiffracted reference wavefronts. The object mask has one or more substantially transparent elements for creating overlapping object wavefronts when the illumination beam is incident thereon. The object mask is disposed in the illumination beam. A holographic recording medium is provided in the illumination beam in line optically with the object mask. The object mask is illuminated with the illumination beam, thereby causing the object mask to allow undiffracted reference wavefronts to pass therethrough. The illumination directed along the axis causes the one or more substantially transparent elements to create object wavefronts which interact with the undiffracted reference wavefronts to create an interference pattern.

Abstract: The present invention relates to a method and an apparatus for forming a hologram from a mask. According to the invention a photoresist is used as the holographic recording medium and the planes of polarisation of the object and reference beams incident on the holographic recording medium are arranged such that their polarisation vectors are substantially mutually orthogonal in the holographic recording medium and such that the polarisation vectors of the incident and totally internally reflected reference beams are also substantially orthogonal. Preferably, just the transmission hologram is formed in the holographic recording layer.

Abstract: A hologram duplicating apparatus (10) includes a first optical system (30) for carrying out exposure recording of holographic stereogram image on a recording medium for hologram to produce an original H1, a second optical system (60) for carrying out exposure recording of image recorded on the original H1 on a recording medium for hologram disposed at a predetermined distance from the original H1 by using diffracted light obtained by illuminating the original H1 to produce intermediate hologram H2, and a third optical system (70) for carrying out exposure recording of image recorded on the intermediate hologram H2 on a recording medium for hologram disposed at a predetermined distance from the intermediate hologram H2 by using diffracted light obtained by illuminating the intermediate hologram H2 to produce edge lit hologram H3.

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: A diffractive optical element such as a diffuser, diffraction grating, and/or hologram, can be manufactured by using a surface relief pattern on a surface of a surface relief tool. A layer of curable material is physically contacted with the surface relief pattern on the surface of the surface relief tool to thereby imprint the pattern on a surface of the layer. Diffractive features are formed in the layer by propagating energy through the surface relief tool and into the layer such that refractive index variations corresponding to the pattern are created in the layer. The resultant product is a diffractive optical element comprising a layer of material having diffractive features formed by a predetermined pattern of refractive index variations. The diffractive features originate at an undulating boundary and extend only from one side of the boundary into the material. The undulating boundary has an undulating pattern that corresponds to the predetermined pattern of refractive index variations.

Abstract: The present invention relates to a method for producing light-scattering elements by holographic illumination of a layer (10) of a photo-sensitive material on a support plate (1) and subsequent development of the layer (10) in order to generating a surface structure. The method is distinguished in that the illumination occurs using at least two mutually coherent luminous beams (2,3) which have passed through one or a plurality of primary diffusers (8,9) respectively were reflected at one or a plurality of primary diffusers, the luminous beams (2,3) being irradiated from different directions and being at least partially superimposed on the layer (10) while forming an interference pattern. This method permits producing diffusers having a leveled scatter profile in a simple manner.

Abstract: An image display device comprising a holographic screen and an image projection device for projecting an image beam onto the holographic screen at an upward or downward angle is provided, wherein a forward view color difference &Dgr;u′v′ between a chromaticity value (u′, v′) at the center of the holographic screen when a white image is projected onto the holographic screen by the image projection device and a standard chromaticity value (u′o, v′o) is 0.04 or less when the projection angle of the image beam onto the center of the holographic screen is set to any angle within a specified projection angle range of 20 to 45°, whereby a image display device and holographic screen can be provided wherein the range of the projection angle of the image beam, in which an image with excellent color reproducibility can be displayed, is wide.

Abstract: A method is disclosed for replicating (copying) a master hologram into a photosensitive layer to produce a copy of the hologram in a manner such that the copy of the hologram is an accurate and true replication of the master hologram with minimum interface-related defects. A holographic element containing a master hologram for use in contact copying is also disclosed.

Abstract: A holographic data storage system having high recording density and compact memory architecture is disclosed. The system includes a laser light source, a spatial light modulator (40) for data input, a beam splitter (50) for separating out part of the parallel laser beams as reference beam, and a beam steering system (60). Parallel laser beams passing through the spatial light modulator (40) form a two-dimensional signal beam carrying digital data. Unique patterns are then generated from interference of the signal beam and the reference beam, which can be recorded into the volume holographic medium (10) with unique incident position {grave over ()} angle and cross sectional phase distribution of reference beam.

Abstract: Disclosed is an optical switch for transmitting or shutting down an input light signal in accordance with a set switching state. The optical switch comprises first and second optical amplifiers connected in cascade. When an optical fiber amplifier comprising EDFs (11 and 12) and pumping sources (31 and 32) is used as the first and second optical amplifiers, the switching is accomplished by switching on or off the pumping sources (31 and 32) in accordance with control signals supplied from a control circuit (300). One input light signal can be dropped through a first optical branch (51) located on the input side of the optical switch, while another input light signal can be added through a second optical branch (53).

Abstract: Disclosed are holographic storage systems and lenses for holographic storage systems. The lens units can be of a two-component design. The lenses can be used to both record to photorefractive storage media and to read from photorefractive storage media.

Abstract: The invention relates to a liquid crystal display device which enables a visual field range to be made wide and luminance drops to be reduced, so that bright displayed images can be presented, and provides a liquid crystal display device comprising, in order from a side of backlight 11, backlight 11, scatter plate 12, and liquid crystal element 20, wherein a transmission type of hologram scatter plate 13 is located in front of a display surface of liquid crystal display element 20. Hologram scatter plate 13, because of having been fabricated by means of single-step or two-step exposure, enables light more or less scattered through scatter plate 12 to be limitedly scattered within a given wide visual field range, so that bright displayed images can be presented over a wide visual field range yet with a reduced luminance drop. Scatter plate 12 may be omitted.

Abstract: A method of recording a surface relief microstructure in a record medium includes: i) causing a coherent reconstruction or replay beam to impinge on a holographic optical element assembly, the holographic optical element assembly including a holographic optical element (HOE), the assembly causing selected portions of the beam to interfere at a focal region after diffraction by the holographic optical element so as to reconstruct a real image of an aperture previously used to construct the HOE; ii) locating a record medium at the focal region so that the real image is recorded; and, iii) causing relative movement between the record medium and the interfering beam portions and repeating steps i) and ii) so that the real image is recorded at a plurality of locations or pixels on the record medium.

Abstract: In the manufacture of an array total internal reflection hologram for printing a pattern of high-quality microfeatures over a large area, a mask defining just a part of the pattern is used to record an array of sub-holograms, the holographic recording medium or the mask being moved with respect to each other subsequent to the recordal of each sub-hologram, thereby building up a hologram of the complete pattern to be printed.

Abstract: The present invention offers increased efficiency and quality in the duplication of a master hologram utilizing an improved method of contact printing. This improved method of contact printing employs a polymer-dispersed liquid crystal (PDLC) recording medium as the duplication blank and/or the master hologram material. The optical qualities of the PDLC material described herein provide an improved method of duplication using single beam contact printing regardless of the material comprising the master hologram. Thus, master holograms originally recorded using highly complex optical geometries (e.g., computer generated holograms) are capable of duplication without the need for multiple beam power/intensity balancing and long recording times. The improved hologram contact printing method described herein works with virtually any type of master hologram, including both reflection and transmission holograms.

Abstract: A hologram recording film has a hologram image of an object recorded in a volume hologram photosensitive material by holographic duplication and further has a hologram image of an additional information pattern, e.g. a character or an image, recorded superimposedly in the same volume hologram photosensitive material simultaneously with the holographic duplication so that the additional information pattern is reconstructable in a plane with a depth from the hologram plane. Reflection type additional information is recorded in the hologram recording film so as to be reconstructable simultaneously in superimposition with a reconstructed image from the volume hologram. In addition, transmission type additional information that is in mirror image relation to the reflection type additional information is recorded in the hologram recording film so as to be reconstructable simultaneously in superimposition with the reconstructed image from the volume hologram.

Abstract: A simplified method is provided for recording identification information, such as a serial number or the like, in a hologram-recorded film simultaneously with hologram duplication. The method includes the steps of coupling a hologram recording film with a master hologram plate having a master hologram, the master hologram plate having a reflective area adjacent the master hologram; and directing laser beams towards the master hologram plate to induce interference between incident laser light and diffraction laser light from the master hologram in the recording film, at least some of the laser beams radiating the reflective area through a transmission type controllable display device to record a pattern in the hologram recording film corresponding to a pattern displayed at the transmission type controllable display device.

Abstract: A method is disclosed for reconstructing an image from a total internal reflection hologram that includes the steps of arranging the hologram in relation to the first face of a coupling body, generating a substantially collimated illumination beam, directing the beam through a second face of the coupling body so that it reconstructs the image recorded in the hologram, recycling at least once the light in the illumination beam that is reflected from the hologram by redirecting it through the second face of the coupling body so that it also reconstructs the image recorded in the hologram, and scanning the illumination and recycled beams across the hologram, for the purpose of increasing the effective reconstruction efficiency of the total internal reflection hologram.

Abstract: A method is provided for producing a holographic optical element that is comprised of at least one primary hologram (as defined herein) and at least one complementary hologram (as defined herein). The holographic optical element is useful as a security device, since it is relatively easily produced and yet is uncopyable in total. Also disclosed are methods for establishing the authenticity of the holographic optical element.

Abstract: The present invention entails a phase mask for producing a plurality of volume gratings for use as optical couplers and method for creating the phase mask. The phase mask is produced by creating a plurality of volume gratings having predetermined characteristics which allow the phase mask, when excited by a coherent light wave, to produce a plurality of volume gratings in a recording material.