Abstract: A lensless holographic imaging system having a holographic optical element includes: a coherent light source for outputting a first light beam and a second light beam, wherein the first light beam irradiates a first inspection plane to form first object-diffracted light; a light modulator for modulating the second light beam into reading light having a specific wavefront; a multiplexed holographic optical element, wherein the first object-diffracted light passes through the multiplexed holographic optical element, and the reading light is input into the multiplexed holographic optical element to generate a diffracted light beam as system reference light; and an image capture device for reading at least one interference signal generated by interference between the first object-diffracted light and the system reference light. The lensless holographic imaging system has a relatively small volume and relatively high diffraction efficiency.

Abstract: An optical information storage medium includes a substrate and a multilayer polymeric film. The multilayer polymeric film has a first surface and an opposite second surface that extend the length of the multilayer polymeric film. The second surface is adhered to a surface of the substrate. The multilayer polymeric film includes a plurality of coextruded alternating polymeric active data storage layers and polymeric buffer layers.

Abstract: The techniques disclosed herein may be utilized to detect, measure, and/or compensate for misalignments of a display that may occur after manufacturing. A Talbot sensor is described that includes a diffraction device and an image sensor. Captured images from the image sensor include pixel data values that include bright and dark spots that represent a diffraction pattern associated with the Talbot sensor. A demodulator multiplies the pixel data values with sine and cosine reference images to generate averaged in-phase and quadrature values, which can be used to determine a phase angle for incident light on the Talbot sensor. Phase angle changes over time indicate changes in the alignment of the display, which may be corrected by display parameter manipulation. The resulting devices, systems and methods provide for portable solutions, with reduced cost of manufacturing, reduced part costs, and reduced complexity.

Abstract: In some examples, QR code based test data embedding and transmission may include obtaining, by a test data analyzer that is executed by at least one hardware processor, test data based on operation of a test device to measure a parameter associated with an optical fiber. Based on an analysis of the test data, a report that includes the test data may be generated. A quick response (QR) code generator that is executed by the at least one hardware processor may compress the report that includes the test data to generate a compressed report. The QR code generator may generate, based on an analysis of the compressed report, a QR code that includes the compressed report. A display generator that is executed by the at least one hardware processor may generate a display of the QR code that includes the compressed report.

Abstract: A system for use in imaging in the air, including: an image source, a transflective mirror and a retroreflective element. Light emitted by the image source is irradiated onto the retroreflective element after being reflected by the transflective mirror, the light is reflected on the retroreflective element and emerges in an opposite direction along an original incident path, and after being transmitted by the transflective mirror, then forms a real image. A selective transmissive film is provided on a side of the transflective mirror facing the image source, and a phase delay optical element is provided on a side of the retroreflective element facing the transflective mirror such that first linearly polarized light incident on the retroreflective element from the transflective mirror becomes circularly polarized light after passing through the phase delay optical element.

Abstract: An electro-optical includes, in part, a multitude of phase modulators each of which includes, in part, a p-type semiconductor region, an n-type semiconductor region, and a ?(2) insulating dielectric material disposed between the p-type and n-type semiconductor regions. The electro-optical device may be a phased array in which each phase modulator is associated with a different one of the transmitting elements of the phased array. The ?(2) insulating dielectric material may be an organic polymer. The electro-optical device may further include, in part, a multitude of sensors each associated with a different one of the phase modulators. Each sensor is adapted to receive a phase modulated signal generated by the sensor's associated phase modulator. The electro-optical device may further include, in part, a multitude of amplitude modulators each associated with a different one of the multitude of phase modulators.

Abstract: According to a positioning method for a hologram in a disk-type holographic storage medium, a guide groove is formed in advance in the disk-type storage medium and is scribed with a positioning marker that includes index information, position information and crossing angle information. The positions of a positioning laser beam and a recording/reproducing laser beam are applied to the same medium position. When an optical head accesses a recording/reading position at a high speed, the shift multiplex recording/reading is performed starting from a marker position. A servo system controls the laser beams to move along the guide groove and ensures that a focused beam is focused on the medium. According to the method, the position and angular information can be quickly positioned in process of performing cross-shift multiplex recording/reading, the recording/reading speed of the system is improved, and random access is achieved.

Abstract: A reproduction apparatus dividing a cross section of superposed light into a plurality of regions in a tangential and/or radial direction includes: an optical system configured to generate each of a first set of signal light and reference light having a phase difference of approximately 0°, a second set of signal light and reference light having a phase difference of approximately 180°, a third set of signal light and reference light having a phase difference of approximately 90°, and a fourth set of signal light and reference light having a phase difference of approximately 270°, using a plurality of superposed light beams corresponding to the divided regions; an optical receiver configured to output signals corresponding to the sets of the signal light and the reference light; and a circuit configured to compute signals as differences between the signals, and obtain a reproduction signal by computation from the computed signals.

Abstract: The present invention relates to a holographic storage device and method for simultaneously recording and reading on two sides, and pertains to the technical field of optical holographic storage. The device and method disclosed in the present invention use a characteristic that orthogonal light would not interfere with each other and a Bragg selectivity characteristic for holographic storage, and use two optical heads to constitute two interference fields orthogonal in polarization directions on two sides of a same position of a holographic storage medium, so as to perform two-path simultaneous recording and reading on a hologram. The device and method provided in the present invention implement two-path parallel recording and reading of holographic storage, and combine shift multiplexing and circumferential rotation multiplexing, thereby improving the speed of an information data recording and reading process while increasing a capacity of the holographic storage.

Abstract: For three-dimensional topography measurement of a surface of an object patterned illumination is projected on the surface through an objective. A relative movement between the object and the objective is carried out, and plural images of the surface are recorded through the objective by a detector. The direction of the relative movement includes an oblique angle with an optical axis of the objective. Height information for a given position on the surface is derived from a variation of the intensity recorded from the respective position. Also, patterned illumination and uniform illumination may be projected alternatingly on the surface, while images of the surface are recorded during a relative movement of the object and the objective along an optical axis of the objective. Uniform illumination is used for obtaining height information for specular structures on the surface, patterned illumination is used for obtaining height information on other parts of the surface.

Abstract: A system for braking a trailer pulled by a vehicle. A trailer braking system is provided on a trailer. An electrically actuated motor drives a worm screw against a worm gear. The worm gear drives a brake actuator to push brake pads into a rotor coupled a wheel on the trailer. A wheel speed monitor reduces braking force of the trailer braking system in response to a predetermined change in wheel speed. An anti-lock braking system reduces trailer wheel skid under braking. Multiple trailer braking systems can be applied to multiple wheels on the trailer to provide more or less braking.

Abstract: An imaging display system in the field of augmented reality technology comprises a waveguide structure (14) disposed on an outer surface of an exit surface (7) of a polarization beam splitter (3) of an optical engine module (A). The waveguide structure is tubular. One end (15) of the waveguide structure is connected to the exit surface and together with the exit surface forms a preset angle (?). The other end of the waveguide structure is a free end. The imaging display system expands an eye motion box (EMB) by means of the waveguide structure. The preset angle formed between the waveguide structure and the exit surface causes light (22) incident on the waveguide structure to undergo total internal reflection inside the waveguide structure.

Abstract: A method for reading and writing with holographic system includes the following operations: (a) providing a reference light and a signal light; (b) transferring the reference light and the signal light to an optical recording medium, for recording an interference grating; (c) changing the reference light and the signal light and repeating the operations (a) to (b) until M interference gratings are recorded on the optical recording medium; (d) providing a reading light to the optical recording medium, for reading the M interference gratings at the same time to generate an interference result, wherein the interference result is a result that diffraction signals of the M interference gratings interfere to each other; and (e) changing the reading light and repeating the operation (d), for obtaining N interference results. A holographic storage system is also disclosed herein.

Abstract: A see-through image display system having an Exit-Pupil-Expander (EPE) to enlarge the eyebox of display is disclosed. The EPE uses a hologram functioning as a micro-lens-array as well as collimation lens.

Abstract: The present invention relates to a system and method for high quality speckle-free phase-only computer-generated holographic image projection. The present invention more particularly relates to a holographic image display system comprising a spatial light modulator to phase modulate light from at least one light source configured to illuminate said spatial light modulator and to provide a phase hologram and projection optics to project said phase modulated light to generate an image formed by said displayed hologram onto an image plane.

Abstract: A device and method for producing light-exposed structures on a workpiece having a light-sensitive surface. An optical unit includes a light source and a diffraction grating for producing a strip-shaped illumination pattern having strips extending in a longitudinal direction and having a pattern width extending transversely. A device moves the surface of the workpiece and optical unit relative to each other according to a path sequence, which includes movement longitudinal paths to produce a first and second light-exposed structure having strips, which is oriented parallel to each other on the workpiece surface. The movement paths are mutually spaced apart by less than the pattern width and the light-exposed structures overlap in such a way that strips of the light-exposed structures lie on each other. To obtain good light exposure of the surface by the illumination pattern, the diffraction grating is set oblique to the surface of the workpiece that is light-exposed by the illumination pattern.

Abstract: A light irradiation method includes splitting light from a coherent light source, which outputs the light at a wavelength equal to or less than 300 nm, into a plurality of branch beams. A wavefront of the light is shaped before splitting the light. The light irradiation method also includes causing the branch beams to intersect at an interference angle equal to or less than 20° to generate interfered light, and irradiating a substrate with the interfered light while continuously conveying the substrate relative to the interfered light.

Abstract: Compact optoelectronic modules are described that, in some implementations, can have reduced heights, while at the same time having very little optical crosstalk or detection of stray light. An optoelectronic module having optical channel can include a support on which is mounted an optoelectronic device arranged to emit or detect light at a particular one or more wavelengths. The module has a cover including an optically transmissive portion over the optoelectronic device. The optically transmissive portion is surrounded laterally by sections of the cover that are substantially non-transparent to the one or more wavelengths. A passive optical element is present on a surface of the optically transmissive portion. A spacer separates the support from the cover. The cover can be relatively thin so that the overall height of the module is relatively small.

Abstract: In a method for measuring radiation, the radiation is temporally and/or spatially separated by a modulator to direct at least N different combinations of radiation incident on each region into at least two and fewer than N distinct directions. The total intensity of radiation in each direction is measured with a detector for each modulator configuration and the detector outputs are analyzed statistically to obtain information relating to the spectral properties of the radiation. In this way substantially all of the energy received at the entrance aperture of a measurement device is encoded into multiple outputs and the multiplexed output is received by a small number of detectors.

Abstract: The present invention relates to a full-field reflection phase microscope. In a preferred embodiment, the invention can combine low-coherence interferometry and off-axis digital holographic microscopy (DHM). The reflection-based DHM provides highly sensitive and a single-shot imaging of cellular dynamics while the use of low coherence source provides a depth-selective measurement. A preferred embodiment of the system uses a diffraction grating in the reference arm to generate an interference image of uniform contrast over the entire field-of-view albeit low-coherence light source. With improved path-length sensitivity, the present invention is suitable for full-field measurement of membrane dynamics in live cells with sub-nanometer-scale sensitivity.

Abstract: The method for manufacturing a plurality of optical modules each comprising a first (C1) and a second (C2) optical component comprises the steps of a) providing a first substrate wafer (S1) on which a plurality of the first optical components (C1) is present on a top side of the first substrate wafer; b) providing a second substrate wafer (S2) having a material region which is a continuous laterally defined region in which material of the second substrate is present, wherein a plurality of the second optical components (C2) is present in said material region; c) achieving a lateral alignment of the first (S1) and second (S2) substrate wafers such that each of the first optical components (C1) is present in a laterally defined region not overlapping said material region; d) interconnecting the first and second substrate wafers in said lateral alignment such that the top side of the first substrate wafer faces a bottom side of the second substrate wafer with no further wafer in between.

Abstract: A pattern inspection apparatus includes a first half-wave plate to receive an ultraviolet light linearly polarized in a first electric field oscillation direction, and output a linearly polarized light polarized in a second electric field oscillation direction obtained by rotating by an integer multiple of 90°, a mirror to reflect the linearly polarized light polarized in the second electric field oscillation direction, and output a linearly polarized light polarized in a third electric field oscillation direction parallel or orthogonal to the second electric field oscillation direction, a second half-wave plate to convert the linearly polarized light polarized in the third electric field oscillation direction, which has been reflected, to a linearly polarized light polarized in a fourth electric field oscillation direction by rotating by an angle different from an integer multiple of 90°.

Abstract: The invention is directed at a miniature grism system. The miniature grism system is a single compact device that comprises a grism with collimating and focusing optics. In an aspect, the grism includes at least one prism and a grating. In an aspect, the miniature grism system, and more specifically the grism, includes at least one prism which is placed on either side of the grating. The focusing optics and the collimating optics are found on opposite sides of the grism system, sandwiching the prism and grating of the grism. In an aspect, the miniature grism system is configured to be retained within a filter wheel. The miniature grism system is configured to be used with telescopes having a small focal ratio.

Abstract: This disclosure provides a device for heating to generate a uniform molten pool, including: a source unit for generating an energy beam; a beam expanding/reducing unit positioned in an energy path of the energy beam for adjusting the diameter of the energy beam; a flat-top conical lens set positioned in the energy path and including at least two flat-top axicons, with the beam expanding/reducing unit positioned between the source unit and the flat-top conical lens set; and a focusing lens positioned in the energy path, with the flat-top conical lens set between the beam expanding/reducing unit and the focusing lens, and the energy beam being focused by the focusing lens. This disclosure generates a uniform molten pool to prevent vaporization splash due to overheating of the material during melting.

Abstract: A holographic display (“display”) for a head-mounted display (“HMD”). The display includes a source configured to emit at least partially coherent light and a beam conditioner that conditions the light from the source into one or more beams of light. The display also includes one or more spatial light modulators configured to encode the one or more beams of light using a hologram of a virtual reality image. The display further includes an objective lens and a conversion lens. The objective lens is positioned to create an intermediate image at a Fourier plane, and the intermediate image is a Fourier transform of the hologram. The conversion lens performs a Fourier transform of the intermediate image to generate an output hologram. The conversion lens also magnifies a portion of the output hologram and directs the magnified portion of the output hologram to an exit pupil of the HMD.

Abstract: An error correction block generated by performing error correction coding to the user data is divided into b number of sectors (b: a natural number), each sector having a number of bits (a: a natural number), the sector is divided into c number of sub-sectors (c: a natural number) and bits are distributed to each of the c number of sub-sectors, arrangement order of the bits is randomized for each sub-sector to which the bits are distributed, the c number of sub-sectors in which the arrangement order of the bits is randomized are combined to generate an interleaved sector, the interleaved sector is divided into c/d (d: a natural number, c?d, and c>d) and e number of divided interleaved sectors (e: a natural number, e?b, and b>e) are combined to generate a pre-modulation block, which is modulated by a modulation rule.

Abstract: An optical information recording/reproducing device which records an interference pattern between a reference beam and a signal beam as a hologram in an optical information storage medium or reproduces information from the optical information storage medium, the optical information recording/reproducing device includes a light source unit which emits a light beam, a signal-beam/reference-beam optical unit which generates the signal beam and the reference beam from the light beam and irradiates the optical information storage medium, a spatial light modulator which adds information to the generated signal beam, a photodetection unit which detects a reproduced beam from the optical information storage medium and acquires a reproduced image constituted by a plurality of pixels arrayed in a lattice shape, and a signal processing unit which performs equalization processing to a first pixel of the reproduced image to have a target characteristic.

Abstract: Provided are an optical information reproduction device and a method therefor with which the influence of reference light reflected from the surface of a disk can be reduced, thereby enabling data to be reproduced in a stable manner in an optical information reproduction device that uses holography.

Abstract: A pattern projector disclosed herein generates and projects a structured light pattern suitable for use in a variety of active depth sensing technologies. In one implementation, a structured light pattern is generated by directing a coherent light beam through a pseudorandom diffuser element. Output of the pseudorandom diffuser element is received by a relay optic configured to spatially filter incident light to generate an output speckle illumination and to project the output speckle illumination to a three-dimensional scene.

Abstract: This disclosure provides systems, methods, and apparatus for a photonic chip. The photonic chip includes one or more electronic components in addition to one or more optical components. An optical coupler can be utilized for coupling external optical fibers or sources with the optical components. The optical coupler can include a beam splitter for splitting an incident light having both trans-electric (TE) and trans-magnetic (TM) polarizations into two beams having only TE and TM polarizations. The light beam with TM polarization is incident on a grating coupler on the chip having a horn section, which includes gratings. The light beam is reflected onto the grating coupler such that the direction of TM polarization is within the first plane of incidence, and the first beam of light is incident on the first plurality of gratings at an angle with respect to a normal to the plane of the first grating coupler.

Abstract: The purpose of the present invention is to provide a hologram reproducing apparatus and a hologram reproducing method, which are suitable for reproducing hologram. The purpose can be achieved by means of a hologram reproducing apparatus, which reproduces information signals by irradiating an optical information recording medium with reference light, and a hologram reproducing method for the hologram reproducing apparatus.

Abstract: An optical information recording and reproducing device that records information on a recording medium and/or reproduces information on the recording medium, using holography is configured to include a laser light source that performs irradiation with laser light, a first light-shielding portion which is capable of switching between transmission and shielding of laser light emitted from the laser light source, and a driving circuit that drives the switching between transmission and shielding of the first light-shielding portion, and a first movement portion that moves the first light-shielding portion.

Abstract: Provided is a holographic recording method in which an interference fringe between a reference beam and a signal beam, modulated according to information regarding a plurality of hologram pixels, is recorded on a holographic recording medium, the holographic recording method including multiplexing-recording the interference fringe of the plurality of hologram pixels such that at least a part of the interference fringe recorded of neighboring hologram pixels of the plurality of hologram pixels is overlapped.

Abstract: Disclosed is a method for manufacturing an optical unit, including a step of bringing two side face portions of a ceramic package into contact with two contact portions of a jig, a step of placing plural light-receiving and light-emitting elements in a predetermined region of the ceramic package with reference to the contact portions of the jig, and a step of connecting the plural light-receiving and light-emitting elements to a wiring line part formed in the ceramic package by using a bonding wire, wherein at least one of the plural light-receiving and light-emitting elements is placed between one of the two contact portions of the jig and another one of the plural light-receiving and light-emitting elements in the step of placing the plural light-receiving and light-emitting elements.

Abstract: This recording/reproducing apparatus that records or reproduces information by radiating light to a recording medium is provided with: a medium rotating unit that rotates the recording medium; a moving unit having a movable unit that is capable of moving within a predetermined plane; a rotation angle detecting unit that detects a rotating angle of the recording medium using an angle detection mark that is provided on the recording medium; a position detecting unit that detects a position of the recording medium using an eccentricity detection mark that is provided on the recording medium; and a member for fixing the rotation angle detecting unit and the position detecting unit. With respect to the member, the movable unit relatively moves within a plane substantially parallel to the recording surface of the recording medium, and the medium rotating unit is fixed to the movable unit.

Abstract: The present method includes a data acquisition process and tomographic image generation processes. In the data acquisition process, holograms of an object light and so forth are acquired for each light with a wavelength by changing the wavelengths of the illumination light, off-axis spherical wave reference light, and inline spherical wave reference light. In the tomographic image generation process, a reconstructed light wave of the object light and a reconstructed light wave of the illumination light on a reconstruction surface are generated from these holograms. A reconstruction light wave with adjusted phase is added up for each wavelength to generate a tomographic hologram. From this, an accurate and focused tomographic image without distortion can be generated.

Abstract: The disclosed embodiments provide for checking documents for security compliance when the documents are printed, scanned, or copied. A security status is determined based on security indicators within a document's content. Security indicators can be located within a document's text, figures, watermarks, security marks, and invisible marks. Security indicators can be found by comparing a document's content to a set of stored indicator descriptions. The indicators found are used to determine a document score and security responses are triggered based on the document score.

Abstract: A hologram apparatus and hologram optical system includes: a light source which emits a light beam; a splitter which splits the light beam emitted from the light source into a first light beam and a second light beam; a first lens for exposing an optical information recording medium to convergent light of the first light beam; an optical path angle varying device which causes the second light beam to become incident at substantially the same position as the first light beam in the optical information recording medium and changes an angle of incidence of the second light beam incident on the optical information recording medium; and an optical path shifting element which shifts a position of a light beam incident on the optical information recording medium, according to an angle to the optical information recording medium of the light beam incident on the optical information recording medium.

Abstract: A holographic data reproduction apparatus is provided. The holographic data reproduction apparatus includes: a charged-coupled device (CCD) that photographs diffracted-light from a recording medium irradiated with reference light, wherein the diffracted-light corresponds to a data page, an operation unit that calculates an optimal threshold value by applying a fitness function (Fit) to a genetic algorithm for detecting a number of error bits of the data page corresponding to the diffracted-light, a control unit that determines an output value of each pixel of the data page based on the optimal threshold value, and a decoding unit that decodes and outputs reproduction data according to the output value of the each pixel. Accordingly, it is possible to minimize a bit error rate (BER) and accurately reproduce holographic data.

Abstract: An optical disc information device is an optical disc information device for reproducing and/or recording information with respect to an optical disc including a track in the form of a groove, and capable of recording information in a land portion and in a groove portion of the groove. The optical disc information device includes a laser light source, an objective lens, a transmittance limiting element, a dividing element, a light detector, a central amplifier, at least two end amplifiers, a gain controller, an adder, a reproduction signal processor, and a control signal processor. The transmittance limiting element includes a first central region, and at least two first end regions which interpose the first central region therebetween, and attenuates light passing through at least the first end regions out of a light flux emitted from the laser light source more strongly than light passing through the first central region.

Abstract: A method for improving I/O performance by a storage controller is provided. The method includes receiving a command completion from a storage device and checking for a command stored in a command queue for more than a predetermined time period. If a command has been in the command queue for more than the predetermined time period, then issuing the command and removing the command from the command queue. If no commands have been stored in the command queue for more than the predetermined time period, then determining if there are any uncompleted commands previously issued to the storage device. If there are not any uncompleted commands previously issued to the storage device, then processing a next command in the command queue and removing the next command from the command queue.

Abstract: The present disclosure relates to a digital hologram display device displaying 3D image as a hologram by using a complex modulation. The digital hologram display device comprising a spatial light modulator including a first pixel outputting a first modulation light by modulating a phase of a first plane-polarized light and a second pixel outputting a second modulation light by modulating the phase of the first plane-polarized light, wherein the second pixel is adjacent to the first pixel; and a light combiner changing a path of the first modulation light outputted from the first pixel so that the path of the first modulation light corresponds to a path of the second modulation light outputted from the second pixel for combining the first modulation light with the second modulation light, wherein a phase of the first modulation light is different from a phase of the second modulation light.

Abstract: A hologram reproducing device which reproduces information from a recording medium having information recorded by interfering a signal beam and a reference beam, provided with a first light-angle change unit which changes an irradiation angle of the reference beam; a second light-angle change unit which changes the irradiation angle of the reference beam; a photodetector which detects a reproduction beam; a first light-angle drive-signal output unit which outputs a drive signal of the first light-angle change unit; a first light-angle control unit which controls the first light-angle change unit on the basis of the output of the photodetector; a second light-angle drive-signal output unit which outputs a drive signal of the second light-angle change unit; a second light-angle control unit which controls the second light-angle change unit; and a light-angle interpolation processing unit which controls a control target value of the second light-angle control unit.

Abstract: An RF hologram is divided in a direction perpendicular to a tangent line of an information track of an information recording surface of an optical disc, and includes a central region including an optical axis of laser light as well as a first end portion region and a second end portion region which sandwich the central region, the central region is formed by a binary diffraction grating and generates ±1 order diffracted light, the first end portion region is formed by a blazed diffraction grating and generates first +1 order diffracted light, the second end portion region is formed by a blazed diffraction grating and generates second +1 order diffracted light, and an RF light receiving element receives both the ±1 order diffracted light, the first +1 order diffracted light, and the second +1 order diffracted light.

Abstract: Provided are an optical information recording/reproduction device and an optical information recording/reproduction method with which retry data during verify error detection can be efficiently recorded. In the optical information recording/reproduction device for recording data on an optical information recording media and reproducing data from an optical information recording medium, if verify error data is detected at a first cure unit region on the optical information recording medium, verify error retry data is recorded at a second cure unit region which is different to the first cure unit region.

Abstract: Devices and methods for recording and reproducing a holographic 3D image are provided. The devices for recording the holographic 3D image comprising: a laser generation unit for emitting a laser beam; a beam splitter unit configured to receive the laser beam from the laser generation unit and split the laser beam into a reference beam and an object beam directed to an object to be photographed; a photorefractive crystal configured to receive the reference beam from the beam splitter and the object beam diffused from the object to form a holographic 3D image; and a rotation unit configured to rotate the photorefractive crystal once every time one holographic 3D image is recorded. The holographic 3D image can be recorded and reproduced by the rotate the photorefractive crystal in light paths of recording and reproduction light beams, respectively.

Abstract: A hologram recording and reproducing apparatus including: a coherent light source; a beam splitter which splits a beam emitted from the coherent light source into a signal beam and a reference beam; a signal beam forming unit which modulates the signal beam split and directs the modulated signal beam onto a hologram recording medium; and a reference beam forming unit which directs the reference beam to be irradiated onto a location on the hologram recording medium which overlaps with a location on the hologram recording medium on which the signal beam is incident, wherein the signal beam forming unit includes: a first light guide member which transmits the signal beam split by the beam splitter; a spatial light modulator (SLM) which modulates the signal beam transmitted through the first light guide member; and a holographic Fourier transformation optical device which focuses the modulated signal beam onto the hologram recording medium.

Abstract: An information recording medium manufacturing method includes steps of forming, on a support, a recording layer containing a polymer compound having an azobenzene structure, irradiating the recording layer with first writing light to form a first light-diffracting structure having a three-dimensional relief pattern on the surface of the recording layer, fixing the relief pattern by forming a deformation preventing layer on the surface of the recording layer, and irradiating the recording layer having the fixed relief pattern with second writing light to forcedly inhibit deformation caused by the movement of molecules, thereby forming a second light-diffracting structure having a refractive index change inside the recording layer.

Abstract: An optical information recording apparatus configured to record information into an information recording medium by using holography, the apparatus including: a signal generation unit configured to generate two-dimensional data; and a two-dimensional spatial light modulator unit configured to display the two-dimensional data and to spatially modulate a transmitted or reflected beam, wherein the two-dimensional spatial light modulator unit includes a signal region and an external region, the signal region displays two-dimensional data based on user data, the external region displays two-dimensional data not including the user data, and the signal generation unit generates two-dimensional data in such a manner that a frequency of the two-dimensional data displayed on the external region becomes equal to or larger than a frequency of the two-dimensional data displayed on the signal region.

Abstract: An optical information recording/reproduction device appropriately adjusting a recording condition and a method and a medium therefor are provided in order to cope with a problem that the signal-to-noise ratio (SNR) during reproduction decreases, unless the condition during recording is adjusted, because of variation in the environment during recording, variation of components such as laser output, variation of production of the device, and the like in the optical information recording/reproduction device using holography. In an optical information recording/reproduction device configured to record or reproduce information to an optical information recording medium by using holography, a recording condition is adjusted, before user data are recorded, in an adjustment area provided for recording condition adjustment in an optical information recording medium.