488results about "Hologram nature/properties" patented technology

A device for holographic reconstruction of three-dimensional scenes includes optical focusing means which directs sufficiently coherent light from light means to the eyes of at least one observer via a spatial light modulator that is encoded with holographic information. The device has a plurality of illumination units for illuminating the surface of the spatial light modulator (SLM); each unit comprises a focusing element (21 / 22 / 23 or 24), and a light means (LS1 / LS2 / LS3 or LS4) that emits sufficiently coherent light such that each of these illumination units illuminates one separate illuminated region (R1 / R2 / R3 or R4) of the surface, whereby the focusing element and the light means are arranged such that the light emitted by the light means (LS1-LS4) coincides close to or at the observer eyes.

An apparatus and method to produce a hologram of an object includes an electromagnetic radiation assembly configured to receive a received electromagnetic radiation, such as light, from the object. The electromagnetic radiation assembly is further configured to diffract the received electromagnetic radiation and transmit a diffracted electromagnetic radiation. An image capture assembly is configured to capture an image of the diffracted electromagnetic radiation and produce the hologram of the object from the captured image.

Provided are an optically addressable spatial light modulator (OASLM) divided into a plurality of segments, and an apparatus and method for displaying a holographic three-dimensional (3D) image using the OASLM. The holographic 3D image display apparatus includes a first light source which emits a write beam, an electric addressable spatial light modulator (EASLM) which modulates the write beam emitted from the first light source according to hologram information regarding a 3D image, a second light source which emits a read beam, an OASLM which receives the write beam modulated by the EASLM and modulates the read beam emitted from the second light source according to hologram information included in the modulated write beam, a scanning optical unit which projects the write beam modulated by the EASLM onto the OASLM, and a Fourier lens which focuses the read beam modulated by the OASLM onto a predetermined space to form the 3D image.

A holographic display device comprising at least one magneto-optical spatial light modulator (MOSLM). The holographic display device may comprise a first MOSLM and a second MOSLM, the first and second MOSLMs encoding a hologram and a holographic reconstruction being generated by the device. An advantage of the device is fast encoding of holograms.

A holographic display comprising light sources (L51, L52, . . . ) in a 2D light source array, lenses (L1, L2, . . . ) in a 2D lens array, a spatial light modulator (SLM) and a beamsplitter, in which there are m light sources per lens, and the light sources are in m-to-one correspondence with the lenses. The beamsplitter splits the rays leaving the SLM into two bundles, one of which illuminates the virtual observer windows for m left eyes (VOWL) and the other illuminates the virtual observer windows for m right eyes (VOWR). In one example, m=1. An advantage is 2D-encoding with vertical and horizontal focusing and vertical and horizontal motion parallax.

A light modulating device comprises a spatial light modulator and a homogenizing element. A group of at least two adjacent pixels of the spatial light modulator form a macropixel: The spatial light modulator is of a type such that its pixels comprise a variable content. Each macropixel is used to represent a numerical value which is manifested physically by the states of the pixels of the spatial light modulator which form the macropixel. For each macropixel a homogenizing element is present in the optical path after the macropixel. The homogenizing element comprises an optical input and an optical output. The homogenizing element is adapted such that output light of the macropixel is entering the optical input of the homogenizing element and is mixed within the homogenizing element and is output at the optical output of the homogenizing element.

A holographic recording apparatus having a source of illumination, a master hologram containing at least one hologram lamina overlaying, a copy substrate containing a holographic recording medium, and a voltage generator for applied a voltage across at least one of the master hologram and the copy substrate. The master hologram diffracts the illumination light into zero order light and diffracted light which interfere in the copy substrate to form a copy of the master hologram. The source of illumination is applied for a predefined exposure time during which the voltage varies the refractive index modulation of at least one of the master hologram and the copy hologram.

Thin film-like material that has printability, that can have unique surface patterns of various kinds, and that can have a design having an effect that has been never produced, and process of producing it are provided. The thin film-like material has a laminated structure in which an adhesive layer and a metal thin layer are laid in this order on the entire surface or parts of the surface of one or each of opposite sides of a base material A surface of the metal thin layer is formed by transfer process as a smooth surface having a mirror pattern, a surface having a mat pattern, a surface having a hairline pattern, a surface having an embossed pattern, a surface having a hologram pattern or a surface having two or more of those patterns combined appropriately.

A polarization-selective diffractive optical element includes a liquid crystal polymer film supported by a substrate. The liquid crystal polymer film includes an array of pixels, each pixel encoded with a fixed liquid crystal director such that each liquid crystal director is aligned in a common plane perpendicular to the liquid crystal polymer film and provides a predetermined pattern of out-of-plane tilts. A size of the pixels in the array and the predetermined pattern are selected such that the liquid crystal polymer film forms a phase hologram for diffracting light polarized parallel to said common plane and a zeroth order diffraction grating for light polarized perpendicular to the said common plane. The non-etched and flat phase hologram is suitable for a wide range of applications.

The present invention relates to a method and an apparatus for 3-D display based on random constructive interference. It produces a number of discrete secondary light sources by using an amplitude-phase-modulator-array, which helps to create 3-D images by means of constructive interference. Next it employs a random-secondary-light-source-generator-array to shift the position of each secondary light source to a random place, eliminating multiple images due to high order diffraction. It could be constructed with low resolution liquid crystal screens to realize large size real-time color 3-D display, which could widely be applied to 3-D computer or TV screens, 3-D human-machine interaction, machine vision, and so on.

The present invention relates to a counterfeit-proof volume hologram multilayer structure capable of securely preventing a counterfeiter from replicating a volume hologram recorded therein. The multilayer structure comprises a transparent surface protective layer, a volume hologram layer, and an adhesive layer which are sequentially laminated and is characterized in that particles having particle diameter of 350 nm or more are dispersed in at least one of the transparent surface protective layer, the volume hologram layer, and the adhesive layer and that the refractive index ratio (nF / nB) is set to be not less than 1.05 or not greater than 0.95, wherein nF is the refractive index of the particles and nB is the refractive index of the medium in which the particles are dispersed, or characterized in that at least either the refractive index ratio (nP / nH) between the transparent surface protective layer and the volume hologram layer or the refractive index ratio (nH / nA) between the volume hologram layer and the adhesive layer is set to be not less than 1.08, wherein nP is the refractive index of the transparent surface protective layer, nH is the refractive index of the volume hologram layer, and nA is the refractive index of the adhesive layer.

An intermediate transfer recording medium is comprised by providing a transfer portion having a receptor layer on a substrate film. The transfer portion is printed with the image and thereafter transferred on a surface of a transfer-receiving material. In the first aspect of the intermediate transfer recording medium, the transfer portion is provided with plural hologram patterns 21 with a hologram mark 22 allocated to each the hologram pattern. According to the first aspect of the invention, since an image is formed on the receptor layer through positioning process using the hologram mark and then the transfer portion is transferred to the surface of the transfer-receiving material, no joint of a print plate appears in the hologram pattern and accuracy of transfer is remarkably excellent. On the other hand, In the second aspect of the intermediate transfer recording medium, peeling strength required to peel the transfer portion from the substrate film at the time when transferring the transfer portion to the transfer-receiving material is controlled in the range of 10 to 150 gf / inch. According to the second aspect of the invention, any transfer failure such as tail-extension or chip of the transfer portion is not caused.

Security element 2, 4 to be embedded in or applied to a security document so that it is visually recognizable from both sides of security document 1 is of multilayer construction and includes interference element I with a color shift effect and diffraction structures 8. Depending on the arrangement of the layers and existing diffraction structures 8 on transparent substrate S the color shift effect and / or the diffractive effects are perceptible from one or both sides of security element 2, 4. The security element is suitable in particular as two-sided windowed thread 4 and as label or transfer element 2 over hole 3.

A 3D content generation system comprising a content generating party that generates 2D content and sends that content to a remote intermediary. The remote intermediary processes the content to facilitate subsequent holographic reconstruction and sends the processed content to a holographic display device which locally generates a 3D holographic reconstruction of the content. An advantage is that 2D content may be processed remotely to provide 3D holographic content.

Photo-thermo-refractive (PTR) glass is a multi-component silicate glass having photosensitivity in rear UV region. A novel process is disclosed for PTR glass sensitization to visible region by means of two-step illumination followed by thermal development. This disclosed process utilizes a first illumination at approximately 325 nm followed by a second illumination with radiation in the visible spectral region out of the region of original photosensitivity of the PTR glass which enables fabrication of complex holographic optical elements for visible region such as plane elements, lenses, curved mirrors, combinations of complex elements and optical correlators. The same process provides a positive increment of refractive index in the bulk of the PTR glass and, therefore, can be used for refractive optical elements recording, such as lenses and waveguides.

In-line holography to create images of a specimen, such as one or more particles dispersed in a transparent medium. Analyzing these images with results from light scattering theory yields the particles' sizes with nanometer resolution, their refractive indexes to within one part in a thousand, and their three dimensional positions with nanometer resolution. This procedure can rapidly and directly characterize mechanical, optical and chemical properties of the specimen and its medium.

A method for the elimination of image speckles in a scanning laser projection is suggested, in which a phase hologram is used for dividing the illumination beam of the projector into partial beams. The partial beams are heterodyned again on the image screen within the image element (pixels) to be projected in such a way that differing speckle patterns are formed which average each other out in the eye of the viewer over time and / or space. Thus, a device is provided especially for the laser projection which substantially eliminates or reduces the speckles at the viewer. However, the beam form and the beam density are hardly or not changed.

Provided is a holographic display that realizes a high-resolution three-dimensional (3D) image as a spatial light modulation panel system having a fast response time and enabling the formation of high-density pixels is developed. The holographic display includes, a spatial light modulator using a polymer thin film or a dielectric thin film that enable the formation of high-density pixels and has a fast response time, a fine displacement panel system sequentially moving the spatial light modulator in synchronization with a hologram fringe signal, and an optical system including a coherent light source, a spatial light modulation panel system, and an optical element that are efficiently disposed. The holographic display has a feature that realizes a high-resolution 3D image in a scheme that integrates and displays an image while sequentially moving a spatial light modulator simply or overlaps a hologram fringe pattern.

The invention relates to a holographic viewing device that enable printing or the like to be directly applied to a transmission hologram substrate without recourse to any frame for supporting and reinforcing a transmission hologram, thereby simplifying construction while enhancing aesthetic and decorative attributes, and a holographic viewing card incorporating it. The holographic viewing device enables a given image or message to be viewed near the positions of point light sources upon viewing the point light sources through a hologram, and comprises a transparent substrate 41, a hologram-formation layer 42 and a printing layer 45. The hologram-formation layer 42 may be any one of a phase type diffractive optical element having a relief structure 43 on its surface, a phase type diffractive optical element having a refractive index profile in its layer, and an amplitude type diffractive optical element having a transmittance profile in its layer.

Holographic display device comprising a first EASLM and a second EASLM, the pair permitting independent modification of phase and amplitude, in which holographic reconstruction is visible through one or more virtual observer windows. An advantage is that an observer may view a holographic reconstruction through one or more virtual observer windows from a device housing a pair of EASLMs which permit independent modification of phase and amplitude.

This invention relates to holographic image display systems, and to related methods and processor control code. We describe a method of displaying an image holographically, the method including: inputting display image data defining said image for display; processing said image data to determine first image data representing a first spatial frequency portion of said image data and second image data representing a second spatial frequency portion of said image data, wherein said second spatial frequency is higher than said first spatial frequency; displaying a hologram of said first image data on a spatial light modulator (SLM) to form a holographically-generated intermediate real image; modulating said intermediate real image using said second image data to display said image.

An image reproducing method and apparatus whereby an image with a wide angle of visibility can be reproduced from a holographic stereogram in a manner less susceptible to blurring. For reproducing an image from a holographic stereogram 80 of an edge lit system, a holographic stereogram 80 is arranged on a lateral side of a cylindrically-shaped light-introducing block 81 and a reproducing illuminating light beam 82 is illuminated on the holographic stereogram 80 via the light-introducing block 81. A reproduced image 85 is produced by a diffracted light beam obtained on diffraction of the reproducing illuminating light beam 82 transmitted through the holographic stereogram 80.

A spatial light modulator for modulating light field amplitude comprises a surface relief grating adapted to act as a diffractive lens, where a material is used to fill at least one groove of a surface grating structure, such that a controllable refractive index birefringence of the material inside the surface relief grating is controlled by an electric field, which leads to a controllable intensity at a fixed focal point.

An authenticating pattern 20 for valuable objects is fabricated as an integrated structure of a substrate layer 21 and a transparent overcoat layer 22 with a viewable interface therebetween containing a light diffracting structure 10. Unique parameters are randomly defined in the light diffracting structure by anisotropic process steps not under full control of the producer during the manufacturing of the diffracting structure to prevent copying or creating an exact replica thereof. The resultant uniquely colored authenticating pattern can be verified by simple observation with the naked eye which is a prerequisite for ubiquitous verification.

A holographic display device comprises a first OLED array writing onto a first OASLM, the first OLED array and the first OASLM forming adjacent layers, and a second OLED array writing onto a second OASLM, the second OLED array and the second OASLM forming adjacent layers. The first and the second OASLMs encode a hologram and a holographic reconstruction is generated by the device when an array of read beams illuminates the first and second OASLMs and the first and second OASLMs are suitably controlled by the first and second OLED arrays. Advantages include that this device permits independent control of phase and amplitude, and the device lends itself to compactness.

According to the present invention, video image data is converted into spatial frequency information using Fourier transformation. The spatial frequency information is provided to information display unit. The spatial frequency information as a phase distribution is displayed on the information display unit, light is irradiated onto the information display unit using a light source, the amount of light that is irradiated by the light source is adjusted based on the video image data. And diffraction light, which is irradiated by the light source and modulated as the spatial frequency information by the information display unit is projected onto projecting unit.

The nature of a volume hologram limits its use in security and sensing applications. Accordingly, a volume hologram segregated into a first and second region recording a first and second image, respectively, and wherein the second region is responsive to stimulus while the first region is protected physically from stimulus is provided. Also provided is a volume hologram with a functional cover disposed thereon to regulate how the volume hologram interacts with the stimulus when in the presence of stimulus. A volume hologram with a removable cover disposed thereon to permit a first recorded image to be viewed, to protect the volume hologram from physical damage, to prevent the volume hologram from interacting with the stimulus, and to be removed, thereby permitting the volume hologram to interact with the stimulus is provided as well. In these ways, the usability of volume holograms in security and sensing applications is increased.

A holographic recording medium having a polymer matrix comprising a developer, wherein the holographic recording medium is capable of recording a latent hologram and the developer is capable of developing the latent hologram into a readable hologram by activation of the developer is disclosed. The holographic recording medium is capable of storing large numbers of holograms in the same volume with better signal resolution than previous holographic media by first recording a multitude of latent (or very weak) holograms in the same volume of space, then applying preferably a non-chemical fixing step to develop the latent holograms into readable holograms. The holographic recording medium and method of this invention cause the holograms to increase in diffraction efficiency, thus preventing complications caused during recording of holograms whereby previously recorded holograms interfere with latter recorded holograms in the same volume of space within the media.