Abstract: A method of computing a computer generated hologram (CGH) for use in displaying a holographic image of a replay object. The method comprising the steps of generating a first computer generated hologram corresponding to the desired replay object (step 1); subdividing the first computer generated hologram into a plurality of blocks, each representing a sub CGH (step 2); for each block or sub CGH, calculating the corresponding replay sub-image hereafter called target wavefront data set (step 3); and generating for each target wavefront data set a second constrained modulation computer generated hologram wherein that second CGH is modulated within constrained values (step 5); and combining the plurality of second constrained modulation computer generated holograms to provide a third complete constrained modulation computer generated hologram (step 6).

Abstract: The invention relates to a holographic display for storing and reducing a spatial structure, having a holographic screen forming the master hologram, and having a projection device which illuminates the holographic screen in order to reproduce the spatial structure. The invention, for the holographic display to be constructed from a plurality of holographic screens which are respectively assigned to a dedicated projection device.

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 hologram laminate allows traces of separation of the hologram to be clearly left on both the adherend and the hologram label and hence makes it possible to prevent reuse of the hologram and is excellent in graphical design function and suitable for certification purposes. A hologram label used for the fabrication of the hologram laminate is also provided. The hologram laminate has a metal thin-film layer, a release pattern, a transparent film, a hologram layer and a surface protective layer laminated on an adherend in the order mentioned. The hologram laminate is separable between the adherend and the transparent film. When the hologram is separated, the metal thin-film layer is left on the adherend in a pattern corresponding to the release pattern. The hologram label has a release sheet in place of the adherend in the hologram laminate.

Abstract: A single-axis illumination system for a multiple-axis imaging system, particularly an array microscope. A single-axis illumination system is used to trans-illuminate an object viewed with an array of imaging elements having multiple respective axes. The numerical apertures of the imaging elements are preferably matched to the numerical aperture of the illumination system. For Kohler illumination, the light source is placed effectively at the front focal plane of the illumination system. For critical illumination, the light source is effectively imaged onto the object plane of the imaging system. The light from a single axis source is separated by a holographic element into fields of view corresponding to respective imaging elements of the array microscope so as to match the numerical aperture thereof.

Abstract: In a system for security marking a product, a surface of the product 10 is covered by a layer 14 of light-transmitting material which exhibits variations in refractive index throughout the material such that for most angles of view the material acts as a conventional diffuser of light and thereby conceals or obscures a marking 12 applied to a surface of the product and covered by layer 14, but for a critical angle of view, or a limited range of angles close to that critical angle, the layer is effectively transparent allowing unimpeded viewing of the marking. In a variant, the marking is itself incorporated in the layer in the form of refractive index variations in the layer.

Abstract: An optical structure 3 having a plurality of minute optical unit areas 4 is formed on a base 2. Each of the minute optical unit areas 4 has a plurality of minute areas A and B storing depth information representing multiple-valued phase information about a Fourier transformation image obtained through the Fourier transformation of an original image. In another embodiment of the present invention, the two adjacent minute optical unit areas 4 have a plurality of minute areas A and B storing depth information representing multiple-valued phase information about Fourier transformation images obtained through the Fourier transformation of different original images, respectively.

Abstract: In one embodiment, an imaging apparatus includes a light modulator array having modulators arranged in a loosely-packed configuration. For example, the modulators may be arranged in columns at a first pitch, and the columns may be spaced at a second pitch. The optically active areas of the modulators may form a repeating pattern including a hexagonal pattern, a rectangular pattern, or a diamond pattern. In one embodiment, the modulators are diffractive light modulators.

Abstract: An optical tracking system for use in an optical receiver of an optical communication system includes a first focus unit, a tracker, and an optical fiber having an angled tip. The first focus unit receives an optical signal to be tracked and focuses it on the angled tip of the fiber. The fiber is connected to a communications detector of the optical communication system. In addition, the angled tip of the fiber reflects a portion of the focused optical signal to the tracker. The tracker processes the reflected portion of the optical signal to correct for any misalignment between the optical signal and the optical receiver.

Abstract: Optical infinite impulse response (IIR) filters are efficient polarization mode dispersion (PMD) compensators, requiring fewer stages than finite impulse response (FIR) filters. IIR filter architectures incorporating allpass filters allow the phase and magnitude compensation to be addressed separately. An IIR filter PMD compensator comprising a polarization beam splitter, allpass filters, polarization rotation devices, a 2×2 filter, and a polarization beam combiner optically coupled is described.

Abstract: Multilayer polymeric films and other optical bodies are provided which is useful in making colored mirrors and polarizers. The films are characterized by a change in color as a function of viewing angle.

Abstract: A holographic shrink wrap element containing a shrink wrap film and a layer on the shrink wrap film, wherein the layer contains a holographic image. A process for preparing a holographic shrink wrap element includes providing, in the following order, a holographic polymer film having a holographic surface, a layer on the holographic surface and a shrink wrap film, and removing the holographic polymer film, leaving the holographic image on the layer.

Abstract: A method and system for generating a hologram include a computer (104) connected to a printer (108). A mathematical description (102) of an object, including for example the physical dimensions of the object, is provided to the computer (104). The computer (104) computes a holographic interference pattern based on the mathematical description (102) of the object, and than transmits the computed holographic interference pattern data (106) to the printer (108). The printer (108) prints or otherwise fixes the holographic interference pattern to a print medium (107) to produce a holograph (110). A holographic (three-dimensional) image (114) of the object can then be produced by directing a light beam (118) from a light source (112) onto a surface of the hologram (110), so that the light will interfere with the pattern to generate the holographic image (114).

Abstract: A light bulb, composed of an envelope and an interiorly disposed light source, generates colored light to an observer by providing a reflective holographic optical element (HOE) diffraction grating associated with the envelope. The envelope also has an outer non-light transmissive area in which is disposed a light transmissive aperture. The HOE diffraction grating is oriented to receive and diffract light from the light source and reflect the diffracted light to the aperture for generating a select color of light to the observer. Such light bulb is made by disposing an apertured envelope of a light transmissive aperture disposed within a non-light transmissive area. A reflective holographic optical element (HOE) diffraction grating is associated with the envelope non-light transmissive area. The HOE diffraction grating is oriented to receive and diffract light from the light source and to reflect the diffracted light to the aperture for generating a select color of light to the observer.

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 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: The image data generator 1 produces image data for recording into a holographic stereogram. The image data generator 1 combines a stereo image model being at least a part of a three-dimensional object image prepared in advance with a separately captured image to provide a synthetic image and produces a parallax image train from the synthetic image. The three-dimensional object image prepared in advance and stereo image model being the part of the three-dimensional object are supplied from the 3D image source 4 to the image data generator 1. The image data generator 1 is also supplied with a two-dimensional image separately captured from the photographic unit 5 such as a digital still camera for example.

Abstract: A light conduction structure that generates short range projection for an object to create aesthetic sense of vision by emitting dazzling, fantastic and colorful lights; includes an inner layer provided with a reflective outer side in while; a middle layer made of color, translucent material in dazzling colors and making light passing through it to become gender, wraps up the outer side of the inner layer; an outer layer made of see-through material wraps up the outer side of the middle layer; and a light conduction holder wrapping up the outer peripheries of the inner, the middle and the outer layers contains an insertion channel to accommodate a plurality of light emission devices.

Abstract: An information carrier includes information in the form of a hologram. In order to increase protection against copying and/or as a simple recognizable additional security feature of this information carrier, the hologram is the combination of a transmission hologram and a reflection hologram.

Abstract: The present invention provides a production process of, duplication plate material for duplication of, and medium provided with an optically diffractive structure such as a hologram and diffraction grating having excellent optically diffractive effect, wherein the optically diffractive structure has a surface configuration having plural corrugation-like convexo-concave shapes, and the convexo-concave shapes of the final medium is formed by using a duplication plate material. The convexo-concave shapes of the duplication plate material have a cross-sectional surface which is crosswise to the peaks of the convexo-concave shapes, and a salient section defined by a salient line and a middle line has a smaller area than that of an adjacent reentrant section defined by a reentrant line and the middle line. Herein, the middle line is drawn by connecting midpoints of the height of the convexo-concave shapes.

Abstract: An image display apparatus comprises a hologram screen 2 formed by bonding a hologram element 20 to light-transmissible films 21 and an illumination device 11 for irradiating image light 10 onto the hologram screen and reproducing an image on the hologram screen 2. The light-transmissible film 21 positioned on the irradiation side of the image light 10 relative to the hologram element 20 has an angle deviation of not greater than 45 degrees between a direction of the light-transmissible film 21 that gives the highest thermal shrinkage ratio and an axial direction in the hologram screen 2. Therefore, the image display apparatus can provide high-quality images without the superposition of an interference pattern on the images on the hologram screen.

Abstract: In a storing mode of an apparatus for sequentially storing and retrieving digital page data, a first/second complex reference beam and a modulated/second signal beam converge on a first/second 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: 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: A privacy filter for use on an electronic display screen, such as a PDA display screen or a laptop display screen, is constructed using holographic imaging technology. The privacy filter consists of a flexible, optically clear photopolymer film having a plurality of holographic images formed thereon. The key aspect of the present disclosure is constructing the master holographic images by imaging the master holographic recording plates at a severe side angle “off angle”. By shooting the hologram at this “off angle”, the resulting hologram is not visible to a person looking directly (perpendicularly) at the resulting hologram. However, the holograms are visible within the remaining fields of view to the right and to the left of center. Creation of the holograms in this manner creates an effective blocking tool for use in the context of a privacy filter.

Abstract: A holographic element (HOE) with multiple apertures formed in a single substrate for use an optical communication system. The multi-aperture HOE can be use instead of an optics unit having one or more separate optical elements for each aperture needed by an optical transmitter, receiver or transceiver. The single substrate reduces complexity and cost relative to conventional system that the use separate optical elements to implement the optics unit.

Abstract: A holographic device, which has first and second roughly coplanar and superposed holograms, which are illuminated by the same non-polarized light beam with at least first and second spectral compositions, the holograms each being recorded in a manner such that in its middle, the axis of the diffracted beam is perpendicular to the direction of the incident beam in this medium, the diffracted beams forming first and second angularly separated light beam with the same polarization, and having different spectral compositions.

Abstract: The invention relates to a method of providing an article with identifying information, in which a hologram is provided from which at least first and second hologram patterns separated physically from each other can be reproduced. In this case, provision is made for the hologram to be produced in such a way that the first and second hologram patterns can generally be reproduced in one and the same direction but in different planes.

Abstract: A microscope system comprises: a control means (18) capable of generating electric control signals (18a); a spatial modulator means (7) having an illuminated surface (7a) to be illuminated by light emitted by a light source (1), and capable of receiving the electric control signal and of spatially modulating reflection characteristic or transmission characteristic of the illuminated surface by a spatial frequency specified by the electric control signal; an illuminating optical means (8, 11) for illuminating a specimen (12) with light spatially modulated by the spatial modulator means; an image detecting means (15) for detecting a signal image formed by signal light emitted by the specimen illuminated by the illuminating optical means; and an arithmetic means (16) for processing signal images formed by using the spatial frequency of at least three different phases set by the control means and detected by the image detecting means to obtain an optical sectioned image.

Abstract: A system and method for detecting differences between complex images are disclosed. The method includes acquiring a first complex image and a second complex image and determining if an aberration value difference exists between the first and second complex images. The aberration value difference is corrected by iteratively modifying the first complex image by an aberration function and comparing the modified first complex image with the second complex image in a high frequency range. The method further determines if the modified first complex image matches the second complex image by modifying the second complex image with a low frequency ratio to replace low frequency components of the second complex image with low frequency components of the first complex image. The high frequency components of the modified first complex image and the modified second complex images are then compared to determine if the first complex image matches the second complex image.

Abstract: A holographic recording material coupled to a plastic substrate can be exposed to an interference pattern formed by at least one coherent light source, and subsequently processed, thereby eliminating the need to transfer the holographic recording material from a glass substrate to the plastic substrate. Additionally, by performing a post-exposure heating step in a liquid bath, the formation of unwanted bubbles between the plastic substrate and the holographic recording material is at least in part prevented.

Abstract: An optical detection type ultrasonic receiving apparatus in which S/N ratio of the detection signal is increased while preventing the apparatus from increase of size and cost. The ultrasonic receiving apparatus includes a light source for generating broadband light, an ultrasonic detecting element including an ultrasonic sensing portion to perform intensity modulation of the light, a spectrum-separating unit for spectrum-separating the modulated light, a photo detecting unit having a plurality of photoelectric converting elements for detecting the spectrum-separated light for each of plural wavelength components to generate at least a first detection signal of a first wavelength component and a second detection signal of a second wavelength component, and processing unit for carrying out processing operation using the first detection signal and the second detection signal to obtain information about the ultrasonic wave received by the ultrasonic detecting element.

Abstract: A substrate surface 10 having a photo-sensitive material surface thereon is simultaneously exposed to four plane waves of light at angles of incidence &thgr;, −&thgr;, &phgr; and −&phgr; subtending from the normal of the surface. The four plane waves create an interference pattern on the substrate so as to cause the formation of a periodic structure on the photo-sensitive material surface of the substrate.

Abstract: There are provided a volume hologram laminate and a label for the preparation of a volume hologram laminate which, when kept in the pressed state, for example, during storage, is less likely to cause spotty hologram defects in the volume hologram layer. The volume hologram laminate comprises a substrate 2 and, stacked on the substrate 2 in the following order, a first pressure-sensitive adhesive layer 3, a volume hologram layer 5, a second pressure-sensitive adhesive layer 4, and a surface protective film 6, the volume hologram layer being such that a hologram has been recorded on a recording material comprising a matrix polymer and a photopolymerizable compound, the volume hologram layer having a glass transition point of 30 to 70° C. and a dynamic storage modulus of 5×105 Pa to 5×107 Pa as measured at a measuring frequency of 6.28 rad/sec and a temperature of 50° C., the pressure-sensitive adhesive layer having a dynamic storage modulus of not less than 2.

Abstract: An optical disk has a holographic security label applied in a recessed portion of the disk. An associated method of applying a holographic label to a recessed portion of an optical disk is also described.

Abstract: The invention provides systems and methods for generating and displaying computational holographic stereograms having a hologram surface and a spatially distinct image surface. A three-dimensional object or scene is captured or synthesized as a stack of views. The holographic stereogram is computed by obtaining a diffractive fringe vector e and a pixel slice v through the stack of views, and generating the holopixel representation f=ev. The holographic stereogram is displayed using one or more image surfaces that are spatially distinct from the hologram surface. the surfaces can be any two-dimensional structures defined on a three-dimensional space, including, but not limited to planar, cylindrical, spherical, or other surfaces. The holographic stereograms are adjustable through variations in an image surface depth, an image surface resolution, a number of image surfaces, and a scene parallax resolution.

Abstract: An optical element is disclosed that is resistant to pressure-induced defects and which contains a hologram, an optical diffuser, a microlens array or a lens. The optical element is useful as a component in liquid crystal displays (LCDs) or other types of displays.

Abstract: Disclosed is a device for producing colored light and an image generating apparatus including such a device. The device includes a switchable light-directing apparatus configured to receive light and a first control circuit coupled to the switchable light-directing apparatus. The first control circuit provides control signals to the switchable light-directing apparatus. In response to the switchable light-directing apparatus receiving a control signal, the switchable light-directing apparatus directs a first portion of the received light to a first region of a plane. Additionally, the switchable light-directing apparatus directs a second portion of the received light to a second region of the plane, and directs a third portion of the received light to a third region of the plane. The second region is positioned between the first and third regions of the plane.

Abstract: The object of the present invention is to provide a holographic notch filter which can favorably reject and remove a narrow, desired range of wavelengths of the incident light and a method of easily manufacturing the holographic notch filter. For achievement of the above object of the present invention, a multi-structure holographic notch filter 2 having a holographic recording material 4 arranged on which modulations of the refractive index are recorded by two-beam interference is provided as characterized in that a thin-film filter element 6 is fabricated from a thin form of the holographic recording material 4 in which modulations of the refractive index are recorded by the two-beam interference and a plurality of the thin-film filter elements 6 are joined together to develop a layer arrangement.

Abstract: An optical system including one or more switchable holographic optical elements is described for use with a pancake window display system. Each of the switchable holographic optical elements of the optical system operates between active and inactive states in accordance with control signals provided by a control logic circuit. In the active state, each switchable holographic optical element operates to reflect and collimate a narrow band of incident light thereon. In the inactive state, the switchable holographic optical element operates to transmit a substantial portion of light thereon without substantial alteration.

Abstract: A free space (FSO) receiver includes an illumination sensing unit with multiple illumination apertures. The illumination sensing unit is used in deriving alignment information from portion(s) of a received FSO signal that are incident on the illumination apertures. The FSO receiver provides this information to the FSO transmitter that transmitted the FSO signal so that the FSO transmitter can adjust the direction it is pointing. The illumination apertures can be formed in a holographic optical element on a single substrate. Further, transmission, reception, tracking and/or spotting scope apertures may be formed in the single substrate.

Abstract: An optical disk has a holographic security label applied in a recessed portion of the disk. An associated method of applying a holographic label to a recessed portion of an optical disk is also described.

Abstract: The present invention relates to a method and apparatus for display of three-dimensional images and production of mega-channel phase-encoded optical communications. In certain embodiments, the device of the present invention allows for the creation and display of real-time, three-dimensional moving holograms. In the present invention, a computed image or virtual model of a real object is stored in a computer or dedicated digital signal processor (DSP). The stored image or model is then converted by the computer or DSP into its Fourier, or holographic, transform. The holographic transform is displayed on a light modulation device that is illuminated by a one portion of a laser emission. The remaining portion of the same laser emission is combined with the holographic transform at a plane to create a three-dimensional image.

Abstract: Disclosed is an apparatus and method of illuminating an image display via an electrically switchable holographic optical element. The method includes a first electrically switchable holographic optical element (ESHOE) receiving illumination light. The first ESHOE comprises oppositely facing front and back surfaces. The first ESHOE focuses a first component (e.g., p-polarized blue light) of the illumination light while transmitting the remaining components of the illumination light without substantial alteration. An image display is provided and receives the focused first component. In response to receiving the focused first component, the image display emits image light. The first ESHOE receives and transmits this image light without substantial alteration. In one embodiment, the focused first component emerges from the first ESHOE at the back surface thereof, and the first ESHOE receives the image light at the back surface.

Abstract: A hologram recording medium comprises a hologram recording layer for recording a hologram, and a wedge substrate for varying the propagating direction of a reference light and an object light incident upon the hologram recording medium. By rotating the hologram recording medium comprising the hologram recording layer and the wedge substrate, the propagating direction of the reference light and the object light are varied, whereby angle multiplex recording of holograms can be realized with ease.

Abstract: A composite sheet having the capability of having embossed therein a holographic image or diffraction grating image has a structure of multiple layers including a plastic film carrier, lacquer, metal and, optionally, a lacquer overlay. It may be adhered to a substrate without the necessity of removing the plastic film carrier and may have a holographic image embossed therein during the step of adhering or in a separate operation at a different time and may have printing applied to the layer of metal or to the lacquer overlay.

Abstract: Holographic lines are formed directly on products by holding a holographic plate and a block under a lip on a frame and mounting the frame for limited movement within a recess in a mold half. As a mold cavity is filled, the frame, block and plate and heating tubes connected to the block move in the recess. As the product sets, springs push the frame, block and plate toward the shrinking product controlling the fine holographic lines. Lateral frame recesses receive bolt ends to limit frame travel. Partially withdrawing bolts and removing the tubes releases the frame for withdrawing the block and replacing the holographic plate.

Abstract: A single photographic subsystem 2 photographs an original image for a hologram and provides an image information file Fp. In addition, this subsystem provides a management information file Fm for storing management information about the image information file Fp. An image processing section 4 generates a composite image file Fs by applying specified image processing to the image information file Fp and the management information about the management information file Fm provided from the single photographic subsystem 2 via a transmission system 3a. A hologram printer 5 receives the composite image file Fs generated in the image processing section 4 and prints a holographic stereogram based on this composite image file Fs.

Abstract: A method and apparatus for making holograms includes a technique for exposing a film substrate or other light-sensitive medium to consecutive two dimensional images, together representative of a physical three-dimensional system, to generate a three dimensional hologram of the physical system. Low beam ratios are employed to superimpose multiple (20-300) images on the substrate. Each image is relatively weak, but the combination of the series of weak images ultimately appears as a single clearly defined hologram.

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 hologram forming layer, transparent evaporated layer, colored layer, adhesion anchor layer, and adhesive layer are sequentially laminated on the under surface of a base member. The laminated body is used as a seal by the presence of the adhesive layer. It is preferable for the base member to have adequate rigidity (flexibility, tensile strength) and surface flatness. The hologram forming layer has a relief type hologram image. The transparent evaporated layer is a multi-layered ceramic layer constructed by alternately laminating high-refractive index layers and low-refractive index layers and the thickness thereof is preferably set to 1 &mgr;m or less. In the transparent evaporated layer, the color of visible light in predetermined wavelength range is changed according to the viewing angle when it is transmitted therethrough or reflected therefrom.