Abstract: A recording apparatus for holographic recording medium having an alignment mark and designed to irradiate a recording light beam onto a recording region of holographic recording medium to record information as a hologram. This apparatus comprises a recording laser recording the hologram onto the medium, an alignment laser irradiating an alignment light beam onto the medium, the alignment light beam being less absorbed than the recording light beam by the medium, and being reflected by the medium, a first lens converging the recording light beam and directing it toward the medium, a second lens converging the alignment light beam and directing it toward the medium, a photodetector detecting a light intensity of the alignment light beam reflected from the medium to recognize the alignment mark, and a driving mechanism adjusting a region to be irradiated with the recording light beam relative to the medium based on the alignment mark.

Abstract: There is provided an optical recording medium comprising a recording layer containing a charge-generating material capable of generating a first electric charge and a second electric charge by beam irradiation, the second electric charge having a different polarity from that of the first electric charge, a charge-transport material enabling at least the first electric charge to be transported to isolate the first electric charge and the second electric charge, and a trapping material retaining the first electric charge. The optical characteristics of the recording layer is changed in accordance with changes in spatial distribution of the first and second electric charges, and the trapping material is provided with a conjugated system and with at least one nitrogen-containing heterocyclic group, and bonded through an unsaturated carbon atom of the heterocyclic group to the conjugated system.

Abstract: A hologram recording medium includes: first and second translucent substrates; and a recording layer, which is formed between the first and second substrates, contains a three-dimensionally crosslinked polymer matrix, a radical polymerizable compound and a photoradical polymerization initiator, shows a rubber-like elasticity at the room temperature, and has a durometer hardness within a range of A45 to A85.

Abstract: A holographic recording medium includes a transparent layer having a servo surface and a light incidence surface which face each other; a reflecting layer formed on the servo surface-side transparent layer; and a holographic recording layer formed on the light illuminating-side transparent layer. The transparent layer includes resin films laminated so that adjacent resin films differ in stretching direction by 90 degrees.

Abstract: A hologram recording/reproducing apparatus includes a recording/reproducing optical system that guides at least one of an information beam and a reference beam to an optical recording medium; a spatial light modulator that is arranged in an optical path of the recording/reproducing optical system, and spatially modulates a beam guided via the recording/reproducing optical system to generate the information beam; a first misalignment detecting unit that detects a first misalignment between the recording/reproducing optical system and the spatial light modulator using a beam for detecting the first misalignment; and a first misalignment correcting unit that corrects the first misalignment based on the first misalignment detected by the first misalignment detecting unit.

Abstract: The optical information recording apparatus includes a laser light source for radiating a light beam, a spatial light modulator disposed on an optical path of the light beam, a power density control mechanism disposed on the optical path, an interference fringe formation mechanism. The spatial light modulator has pixels arranged in a two-dimensional array at which a central section of the light beam is radiated. The spatial light modulator spatially modulates the light beam. The power density control mechanism is set such that the transmittance with respect to the light beam at a portion where the central section is radiated is lower than that at which a peripheral section of the light beam is radiated. The interference fringe formation mechanism forms interference fringes from the central section and the peripheral section on the optical information recording medium disposed downstream on the optical path.

Abstract: Information is recorded/reproduced by focusing a light beam in/from an optical recording medium capable of forming therein marks for information recording in a plurality of three-dimensional directions including an arbitrary directions and at least depth direction. Specifically, the optical beam is sequentially focused at a recorded mark position adjacent an optically recorded mark position, at which a recording/reproducing operation is started, in any directions regardless of the directionality of the plurality of three-dimensional directions, to cause the focused position of the light beam to describe a predetermined locus having a predetermined rule to rapidly and continuously record/reproduce the information.

Abstract: Disclosed is a holographic recording medium and methods of manufacturing the holographic recording medium. The example of the medium has a recording layer containing a three dimensionally cross-linked polymer matrix including an epoxy resin, a radically polymerizable monomer, and a photo radical polymerization initiator. The radically polymerizable monomer comprises both N-vinylcarbazole (VC) and N-vinylpyrrolidone (VP) or N-vinylcarbazole alone. The weight ratio of N-vinylcarbazole (VC) to the sum of N-vinylcarbazole (VC) and N-vinylpyrrolidone (VP), i.e., (VC/(VC+VP)), is not smaller than 0.75 and not larger than 1.0.

Abstract: Provided is a technique for reproducing information recorded on a holographic recording medium including a reflecting layer and a recording layer. When reproducing, a reproducing reference light is focused on a reflecting surface of the reflecting layer to produce a phase conjugate reproduced light and an ordinary reproduced light, and the phase conjugate reproduced light and the ordinary reproduced light are guided to a sensing surface of an image sensor to produce on the sensing surface a first reproduced image and a second reproduced image smaller than the first reproduced image, respectively. An intensity of the ordinary reproduced light on the sensing surface is higher than an intensity of the phase conjugate reproduced light on the sensing surface. An output of the image sensor corresponding to a non-overlapping portion of the first reproduced image which does not overlap the second reproduced image is utilized for reproducing the information.

Abstract: Disclosed is a holographic optical recording medium, comprising a recording layer containing a three dimensionally cross-linked polymer matrix, a radically polymerizable compound, and a photo radical polymerization initiator, the three dimensionally cross-linked polymer matrix comprising a cured material of a reaction product between a diglycidyl ether and an amine, the diglycidyl ether being selected from the group consisting of 1,6-hexanediol diglycidyl ether and diethylene glycol diglycidyl ether.

Abstract: An optical recording medium has a recording layer recording information as hologram by receiving a beam of light corresponding to the information. The recording layer includes a plurality of recording areas which are physically separated in a direction, the direction is substantially parallel to a surface that the beam of light enters and a boundary area provided between the recording areas to separate the respective recording areas.

Abstract: Disclosed is an optical recording medium comprising a recording layer. The recording layer contains: a charge generation material generating an electron and a hole by light irradiation; a charge transport material transporting one of the electron and the hole; a charge trap which traps the transported one of the electron and the hole to separate the electron and the hole; and a non-linear optical material which changes optical properties of the recording layer in accordance with electric field formed by the electron and the hole being separated from each other. The non-linear optical material has an asymmetrical carbon atom and a cyclic group. Or, it is a cyclic-group-containing constituent having: an inversion symmetric pi-electron system; at least one of an electron donating group and an electron accepting group which are bonded to the inversion symmetric ?-electron system; and an asymmetrical carbon atom.

Abstract: A method for storing holographic data in a medium having a reflection layer and a recording layer comprises: recording, rotating and repeating. An interference pattern is recorded at a recording position of the recording layer of the medium in a stationary state. The interference pattern is formed by an interference between an object beam and a reference beam which are irradiated into the recording layer from an opposite side of the reflection layer. The medium is rotated so as to shift the recording position by a distance of n×Sh where n is a positive integer and Sh is a predetermined recording shift amount. The recording and the rotating are repeated alternately.

Abstract: Disclosed is a holographic optical recording medium comprising a recording layer having a skeleton structure represented by following general formula (A): where R1 denotes an atomic group selected from the group consisting of a linear or branched alkylene group having 1 to 10 carbon atoms and an arylene group having 1 to 10 carbon atoms, it being possible for a halogen atom or an alkoxy group to be substituted in R1, and each of p and q is 0 or 1.

Abstract: Disclosed is a recording medium comprising a recording layer including a photo-acid generating agent that generates an acid upon irradiation with an actinic radiation and a polymer having a polymerizable substituent group bonded to a main chain of the polymer via a functional group that cleaves in the presence of the acid.

Abstract: A holographic recording medium includes a transparent layer having a servo surface and a light incidence surface which face each other; a reflecting layer formed on the servo surface-side transparent layer; and a holographic recording layer formed on the light illuminating-side transparent layer. The transparent layer includes resin films laminated so that adjacent resin films differ in stretching direction by 90 degrees.

Abstract: A hologram recording medium has a transparent substrate having an incidence surface, on which a write beam and a reference beam are made incident, and a servo surface opposite to the incidence surface, the servo surface including a header section and a data section, a reflecting layer formed on the servo surface of the transparent substrate, and a hologram recording layer provided on the incidence surface of the transparent substrate, the servo surface having intermittent tracking grooves in the data section except for recording positions, and a width of the tracking grooves being set at a value to less than an e?2 diameter of the reference beam.

Abstract: Provided is a holographic recording medium including a recording layer in which information is to be holographically recorded, and a light-shielding layer which faces a main surface of the recording layer. The transmittance of the light-shielding layer for a recording light is increased on increasing intensity of the recording light. Alternatively, the light-shielding layer selectively transmits the recording light.

Abstract: The optical information recording medium according to the present invention includes a transparent substrate having a first surface and a second surface, a recording layer that is arranged on the first surface of the transparent substrate, and a reflection layer arranged on the second surface of the transparent substrate. A hologram is recorded in the recording layer when a signal light and a reference light are incident from an incident side opposite to the transparent substrate. An optical density of the recording layer corresponding to the signal light decreases from the incident side toward the transparent substrate.

Abstract: A holographic optical recording medium includes a plastic substrate, a first inorganic intermediate layer formed on the plastic substrate, and an organic recording layer on which information is recorded by using holography. The organic recording layer is formed on the first inorganic intermediate layer.