Abstract: The present invention relates to a lens system for an apparatus for reading from and/or writing to holographic storage media, and more specifically to a lens system optimized for an apparatus with a coaxial common aperture arrangement of an object beam and a reference beam. According to the invention, the lens system, which Fourier transforms an object beam and focuses a reference beam into a hologram layer of a holographic storage medium, and which focuses a servo beam onto a servo area of the hologram layer, includes a moving part acting on the object beam, the reference beam and the servo beam, and a fixed part acting only on the servo beam.

Abstract: A head mounted display is disclosed that utilizes a single video display screen to transport images to both eyes. Multiple reflections are created by illuminating the display screen form a plurality of directions, or by illuminating the display screen with light beams of differing polarizations. The reflections of the display screen are focused in order to reduce the splitting volume and then redirected by a plurality of reflective surfaces located near the focal point of the display images. Different images may be sent to each eye of a user by interlacing multiple data streams for the display and linking each data stream with a specific illumination direction, or specific polarization.

Abstract: The present invention relates to a holographic storage system, and more specifically to a holographic storage system using a phase spatial light modulator. According to the invention a holographic storage system with a phase SLM for imprinting a 2-dimensional phase data pattern onto an object beam includes a common path interferometer for converting the phase data pattern of the object beam into an intensity data pattern.

Abstract: A head mounted display is disclosed that utilizes a single video display screen to transport images to both eyes. Multiple reflections are created by illuminating the display screen form a plurality of directions, or by illuminating the display screen with light beams of differing polarizations. The reflections of the display screen are focused in order to reduce the splitting volume and then redirected by a plurality of reflective surfaces located near the focal point of the display images. Different images may be sent to each eye of a user by interlacing multiple data streams for the display and linking each data stream with a specific illumination direction, or specific polarization.

Abstract: The invention describes a collinear optical head for a reflection-type holographic recording medium, which is capable of obtaining an increased capacity. The optical head presented here allows for high capacity by combining holographic multiplexing methods, based on a shift and/or phase-coded reference beam, and/or scanned reference beam and/or angle and/or confocal addressing techniques. The parallel reading method and the format of the holographic recording medium ensure high-speed data transfer. Combined multiplexing is implemented in the system by means of a confocal optical arrangement that reduces crosstalk between adjacent holograms by filtering out object beams unintentionally reconstructed from non-addressed holograms.

Abstract: The present invention relates to a lens system for an apparatus for reading from and/or writing to holographic storage media, and more specifically to a lens system optimized for an apparatus with a coaxial common aperture arrangement of an object beam and a reference beam. According to the invention, the lens system, which Fourier transforms an object beam and focuses a reference beam into a hologram layer of a holographic storage medium, and which focuses a servo beam onto a servo area of the hologram layer, includes a moving part acting on the object beam, the reference beam and the servo beam, and a fixed part acting only on the servo beam.

Abstract: A head mounted display is disclosed that utilizes a single video display screen to transport images to both eyes. Multiple reflections are created by illuminating the display screen form a plurality of directions, or by illuminating the display screen with light beams of differing polarizations. The reflections of the display screen are focused in order to reduce the splitting volume and then redirected by a plurality of reflective surfaces located near the focal point of the display images. Different images may be sent to each eye of a user by interlacing multiple data streams for the display and linking each data stream with a specific illumination direction, or specific polarization.

Abstract: A head mounted display is disclosed that utilizes a single video display screen to transport images to both eyes. Multiple reflections are created by illuminating the display screen form a plurality of directions, or by illuminating the display screen with light beams of differing polarizations. The reflections of the display screen are focused in order to reduce the splitting volume and then redirected by a plurality of reflective surfaces located near the focal point of the display images. Different images may be sent to each eye of a user by interlacing multiple data streams for the display and linking each data stream with a specific illumination direction, or specific polarization.

Abstract: There is disclosed a method and apparatus for coding data, for the purpose of preventing unauthorised readout of information. In the method, user information is converted into digital data (UD), and the digital data is recorded in a first data set (CD) and a second data set (HD), where the first data set (CD) is recorded in a first optical storage medium of a data carrier, and the second data set (HD), is recorded in a second, holographic storage medium of the data carrier. According to the method, the digital data (UD) is divided between the first and second data sets (CD,HD) in a manner so that a part of the user information is contained only in the first data set (CD), and another part of the user information is contained only in the second data set (HD), and the relative proportion of the user information in the data sets is selected so that the information contained in any one of the data sets is insufficient by itself to restore the complete user information (UD) contained in both data sets.

Abstract: A mechanism for adjusting an apparatus for the inter-pupilar distance of a user is disclosed. Example embodiments of the disclosed mechanism use gears that link the movements of eye-optics and reflectors placed along the optical path. When the eye-optics are adjusted, this movement causes a movement in the linked reflectors that maintains a constant length for the optical path.

Abstract: A method and apparatus for improving the quality of light emitted from an HMD lightsource. A backlight-type lightsource is disclosed that utilizes a reflective end-wall 17 to reflect light within the lightguide. Light emitted from an illumination source and reflected from the end-wall 17 combine within the lightguide to produce light with high contrast and homogeneity. A microprism array, consisting of microprisms of uniform height and equidistant spacing, is positioned along the bottom surface of the lightguide. A portion of the combined light incident upon the microprism array is reflected in a direction substantially perpendicular to the lightguide top surface, which comprises an aperture. Light having increased brightness and homogeneity passes through the aperture. Light incident upon the top surface outside of the aperture is reflected within the lightguide so that it may subsequently be transmitted through the aperture.

Abstract: The invention describes a collinear optical head for a reflection-type holographic recording medium, which is capable of obtaining an increased capacity. The optical head presented here allows for high capacity by combining holographic multiplexing methods, based on a shift and/or phase-coded reference beam, and/or scanned reference beam and/or angle and/or confocal addressing techniques. The parallel reading method and the format of the holographic recording medium ensure high-speed data transfer. Combined multiplexing is implemented in the system by means of a confocal optical arrangement that reduces crosstalk between adjacent holograms by filtering out object beams unintentionally reconstructed from non-addressed holograms.

Abstract: The present invention relates to a holographic storage system, and more specifically to a holographic storage system using a phase spatial light modulator. According to the invention a holographic storage system with a phase SLM for imprinting a 2-dimensional phase data pattern onto an object beam includes a common path interferometer for converting the phase data pattern of the object beam into an intensity data pattern.

Abstract: The object of the invention is a high data density holographic data storage method. The holograms are written into the volumetric data storage layer or layers, and during the writing process the accurate places of holograms in the data carrier structure are determined by the intersection domain of the object and reference beam or beams, and during the reading process the selection of holograms simultaneously illuminated by the reference beam or beams, the read-out of the addressed hologram, and the suppressing of un-addressed holograms are carried out by a spatial filter located confocally with the addressed hologram and/or by satisfying the Bragg condition. The optical arrangement for recording and reading out holograms has three dedicated planes in confocal arrangements, where the addressed hologram is in the middle dedicated plane in the storage material, and in the two outer dedicated planes there are spatial filters. The optical arrangement is a 12f optical System consisting of three pairs of objectives.

Abstract: A head mounted display is disclosed that utilizes a single video display screen to transport images to both eyes. Multiple reflections are created by illuminating the display screen form a plurality of directions, or by illuminating the display screen with light beams of differing polarizations. The reflections of the display screen are focused in order to reduce the splitting volume and then redirected by a plurality of reflective surfaces located near the focal point of the display images. Different images may be sent to each eye of a user by interlacing multiple data streams for the display and linking each data stream with a specific illumination direction, or specific polarization.

Abstract: A mechanism for adjusting an apparatus for the inter-pupilar distance of a user is disclosed. Example embodiments of the disclosed mechanism use gears that link the movements of eye-optics and reflectors placed along the optical path. When the eye-optics are adjusted, this movement causes a movement in the linked reflectors that maintains a constant length for the optical path.

Abstract: A head mounted display is disclosed that utilizes a single video display screen to transport images to both eyes. Multiple reflections are created by illuminating the display screen form a plurality of directions, or by illuminating the display screen with light beams of differing polarizations. The reflections of the display screen are focused in order to reduce the splitting volume and then redirected by a plurality of reflective surfaces located near the focal point of the display images. Different images may be sent to each eye of a user by interlacing multiple data streams for the display and linking each data stream with a specific illumination direction, or specific polarization.

Abstract: A head mounted display is disclosed that utilizes a single video display screen to transport images to both eyes. The image of this display screen is focused in order to reduce the splitting volume and then split by a plurality of reflective surfaces located near the focal point of the image.

Abstract: There is disclosed a method and apparatus for coding data, for the purpose of preventing unauthorised readout of information. In the method, user information is converted into digital data (UD), and the digital data is recorded in a first data set (CD) and a second data set (HD), where the first data set (CD) is recorded in a first optical storage medium of a data carrier, and the second data set (HD), is recorded in a second, holographic storage medium of the data carrier. According to the method, the digital data (UD) is divided between the first and second data sets (CD,HD) in a manner so that a part of the user information is contained only in the first data set (CD), and another part of the user information is contained only in the second data set (HD), and the relative proportion of the user information in the data sets is selected so that the information contained in any one of the data sets is insufficient by itself to restore the complete user information (UD) contained in both data sets.

Abstract: A head mounted display is disclosed that utilizes a single video display screen to transport images to both eyes. The image of this display screen is focused in order to reduce the splitting volume and then split by a plurality of reflective surfaces located near the focal point of the image.