Abstract: A spatial light modulator system includes a concentration layer including an array of optical concentrators, such that each concentrator concentrates a portion of an input light beam. A modulation layer includes an array of light modulators each in optical communication with one of the optical concentrators for modulating the portion of the input light beam. The light modulators are spaced apart from one another in the modulation layer to form gaps between adjacent ones of the light modulators. A coil of each light modulator can surround a Faraday element or core containing a Faraday material to control a magnetic state of a Faraday material responsive to control signals.

Abstract: A semiconductor memory device includes a first electrode film, a second electrode film separated from the first electrode film in a first direction, a third electrode film separated from the second electrode film in the first direction, a fourth electrode film separated from the third electrode film in the first direction, and a first and a second semiconductor members extending in the first direction. The second electrode film includes a first conductive portion, an insulating portion, and a second conductive portion arranged along a second direction. The first semiconductor member pierces the first, third and fourth electrode films and the insulating portion of the second electrode film. The second semiconductor member pierces the first, third and fourth electrode films, and the first conductive portion or the second conductive portion of the second electrode film.

Abstract: A prism coupled waveguide-fed solar collector array optimized for geometric fill factor. An integrated linear array of prisms is arranged with their input faces in a common plane. The exit faces of the prisms each feds a corresponding optical waveguide and detector.

Abstract: Techniques are presented to reduce the amount of read disturb on partially written blocks of NAND type non-volatile memory, both for when determining the last written word line in a block and also for a read operation, including post-write verify reads. Non-selected word lines that are unwritten are biased with a lower read-pass voltage then is typically used. The determination of the last written word line of a block can be done in a coarse-fine search, where the word lines are divided into a number of zones to find the zone with the last written word line, which is in turn sub-divided for a finer search.

Abstract: According to an embodiment of the invention, a method of making a magnetic random access memory device includes: forming a magnetic tunnel junction on an electrode, the magnetic tunnel junction comprising a reference layer positioned in contact with the electrode, a tunnel barrier layer arranged on the reference layer, and a free layer arranged on the tunnel barrier layer; depositing an encapsulating layer on and along sidewalls of the magnetic tunnel junction; depositing an interlayer dielectric layer on the encapsulating layer disposed on the magnetic tunnel junction; annealing the magnetic tunnel junction; and implanting hydrogen in a portion of the magnetic tunnel junction. According to another embodiment of the invention, implanting of hydrogen in a portion of the magnetic tunnel junction occurs after forming a magnetic tunnel junction trench. An MRAM device with hydrogen atoms incorporated in a portion of the magnetic tunnel junction is also disclosed.

Abstract: The invention encompasses beam expanders and methods of using such beam expanders. A beam expander according to the present invention may advantageously be used with an interferometer. Beam expanders according to the present disclosure contain at least an input and an output lens, with the output lens having a plano-convex arrangement such that the surface of the output lens is optically flat and can be used as the reference surface in a Fizeau interferometer. The beam expander may also encompass a housing, a partially reflective coating and an anti-reflective coating.

Abstract: A holographic system for storing data on an interference pattern in a hologram storage medium includes a light source for emitting a laser beam, a beam splitter, modulating means and a refractive material. The beam splitter divides the laser beam into a reference beam and a signal beam and the modulating means modulates the signal beam to generate a modulated signal beam. The refractive material refracts the reference beam to generate a refracted reference beam, wherein the refracted reference beam interferes with the modulated signal beam in the hologram storage medium to generate the interference pattern.

Abstract: An optical memory device includes a plurality of optical memory cells, each optical memory cell including at least one wavelength filter, at least one read/write/erase filter, and a plurality of optical strands, wherein each optical memory cell stores and transmits data in optical form. The optical memory device interacts with an array of photon detectors, an array of lasers, and at least one central processing unit. A method of optically storing data in an optical memory device includes providing an optical memory device including a plurality of optical memory cells, each optical memory cell including at least one wavelength filter, at least one read/write/erase filter, and a plurality of optical strands; and storing and transmitting data in optical form in at least one of the plurality of optical memory cells.

Abstract: A reverse bias voltage in combination with selective illumination can selectively write data into optical memory. The writing process can be completed quickly since parallel writing of data may be performed. The writing process generates an avalanche current that is used to change an element. The change can be destruction of the element or may be the alteration of property such as conductance or work function.

Abstract: A high memory capacity with relatively low demands on the optical quality of the components used is possible in accordance with the invention by the means to generate the at least two light rays and/or the memory element and/or means to guide the light rays are designed in such a way that the spatial orientation of the interference sample generated in the memory element by the light rays can be changed in any spatial direction over the spatial orientation of an interference pattern stored in the memory element and/or a light diffracting structure present in the memory element. The invention further relates to a device for the readout of optical information and a method for the optical recording and for the optical readout of information.

Abstract: A ultra-high density memory device utilizing a photoinductive ferromagnetic thin film. A photoinductive ferromagnetic thin film is formed on a GaAs substrate, and a tip is arranged so as to face the photoinductive ferromagnetic thin film. The GaAs substrate is disposed on an xyz scanner, and the three-dimensional positional relationship between the GaAs substrate and the tip is changed by the xyz scanner. Blue light is radiated onto the thin film in order to make the magnetization orientation of molecules uniform. Through application of a relatively high voltage, a relatively large current is caused to flow between the tip and the substrate, so that randomization of the magnetization orientation of molecules of the photoinductive ferromagnetic thin film; i.e., writing operation is carried out.

Abstract: An optical memory stores data in an optical data layer capable of selecting altering light such as by changeable transmissivity. Data is organized into a plurality of regions or patches (called pages) in which each page contains a field of data spots storing binary data as the presence or absence of a hole. The data is illuminated by controllable light sources and an array of single element diffractive imaging lenslets, one for each data page, projects the image onto a common array of light sensors. By selective illumination of each data page, one of the single element lenslets images the selected data page of holes onto the light sensors. By selecting a hole size and using a certain range of restricted acceptance angle grooves on the diffractive elements, the data image is optimized for a single diffractive element lens.

Abstract: A compact memory uses magnetic bubble technology for providing data storage. A three-dimensional arrangement, in the form of stacks of magnetic bubble layers, is used to achieve high volumetric storage density. Output tracks are used within each layer to allow data to be accessed uniquely and unambiguously. Storage can be achieved using either current access or field access magnetic bubble technology. Optical sensing via the Faraday effect is used to detect data. Optical sensing facilitates the accessing of data from within the three-dimensional package and lends itself to parallel operation for supporting high data rates and vector and parallel processing.

Abstract: A method of this invention is a non-overwritable method of recording information on a magnetooptical recording medium in which at least two layers including a first layer comprising a magnetic thin film having a perpendicular magnetic anisotropy, and a second layer comprising a magnetic thin film having a perpendicular magnetic anisotropy, and having a Curie temperature higher than or almost equal to a Curie temperature of the first layer are stacked to be exchange-coupled to each other, and a direction of magnetization of only the second layer can be aligned in a predetermined direction by a first external field at a room temperature while a direction of magnetization of the first layer is left unchanged. The medium which has already been set in a state wherein the direction of magnetization of the second layer is aligned in the predetermined direction, and a interface magnetic wall is formed between the first and second layers is prepared. A beam is radiated on the prepared medium while rotating the medium.

Abstract: A three-dimensional combined magneto-optic memory and logic processor consisting of layers of magnetic bubble material spaced from and parallel to one another. Each layer has a pattern of magnetic bubbles formed under the control of an external data processing system. A laser beam is directed through the layers, and binary signals corresponding to the overall patterns of the magnetic bubbles on all the layers which intersect the beam are detected by a first detector array. Data and logic functions are programmed on to each layer by appropriate control of the magnetic bubbles by the external processing system. Wave guides are provided to reflect light from the magnetic bubbles to a second detector array. In this manner, the two detector arrays may be caused to generate electric signals representing data and logic functions, thereby eliminating the bottle-neck between processor and memory which is prevalent in prior art data processing systems.

Abstract: Disclosed is an improved magnetic bubble recording device for optically effecting writing, reading and erasure of information with respect to magnetic bubbles. The magnetic bubble recording device has a basic structure in which a first magnetic film for forming a magnetic bubble therein and a second magnetic film for imparting a bias magnetic field to the first magnetic film to stably hold the maganetic bubble in the first magnetic film are provided on a substrate on which is formed a transfer pattern for transferring a magnetic bubble along the transfer pattern, thereby providing a portable magnetic bubble recording device at low cost and with a simple structure. In addition, an alignment pattern for aligning the device with a light beam applied to the device is formed on the device, thereby permitting accurate writing and reading. The peripheral edge portion of the pattern of a transfer channel has a surface inclined with respect to the substrate surface so as to transfer the magnetic bubble favorably.

Abstract: A solid state memory device has a thin film for bubble memory, a laser light source, and optical means using a laser light emitted from the laser light source to cause information to be stored in the form of bubbles on the thin film for bubble memory and reproduce the stored information.

Abstract: There is disclosed a method of recording and/or reproducing in/from a Bloch line memory, including the step of: radiating or guiding a light beam to a vicinity of a distal end of a magnetic domain capabable of forming a Bloch line therein or on an extending line thereof.

Abstract: A magnetic memory has a substrate, a magnetic film provided on the substrate including a recording medium capable of producing a recording carrier, and a light waveguide layer on the magnetic film or on that surface of the substrate which is opposite to a surface on which the magnetic film is present. Recording and reproduction of information are effected relative to the magnetic film by a light propagated through the light waveguide layer.

Abstract: An optical system, useful as a magnetometer and as a polarization contoller, is disclosed. The system includes a source of electromagnetic radiation, a detector of electromagnetic radiation, and a magnetizable medium via which the source and detector communicate with one another. The system further includes apparatus for forming at least two adjacent magnetic domains separated by at least one domain wall.

Abstract: A hologram transducer using the Faraday effect in magnetic bubble devices for recording and reproducing the amplitude and phase distributions over a section of a beam of coherent light is disclosed. The transducer spatially modulates the intensity, by using linear polarization, and the phase, by using circular polarization, of light transmitted through a magnetic bubble device. Using linear polarization and a single magnetic bubble domain to traverse in a sequence the possible storage positions in the magnetic bubble device, the transducer samples at each of these positions the intensity of the transmitted light. Using in addition a coherent reference beam of light to interfere with the light being measured, the transducer samples the phase in the half range of 0 through .pi. radians at these positions. Further, using a quarter cycle phase shift in the reference beam, the transducer resolves the phase values over the full range of 0 through 2.pi. radians.

Abstract: A three-dimensional magnetic bubble memory apparatus formed of at least two arrays of sheets, with the sheets of each array being mounted in spaced and parallel relationship and with the sheets of the two arrays being perpendicular to one another, and with each sheet being formed of light-transparent material producing magnetic bubble domains, and with a multiplicity of bubble generators being located along one edge of each sheet and being responsive to selected input signals for producing arrays of magnetic bubbles for movement along parallel channels on each sheet to selected positions representative of binary data to be stored in the memory apparatus, and which includes a light source positioned on one side of each array for directing a polarized light beam to the corresponding array, and a multiplicity of photocells positioned on the other side of each array respectively aligned with the locations on the sheets of the corresponding array at which magnetic bubbles are selectively positioned so that the amp

Abstract: A region (21) having different magnetic energy from that of other portion is formed in a layer (1b) of soft magnetic material which has an easy axis of magnetization normal to the layer surface and is magnetized in one direction by applying an external bias magnetic field. By irradiating a light beam on the layer surface, a cylindrical magnetic domain b magnetized in the direction opposite to the magnetization direction is formed at a first stable position of the region (21). This cylindrical magnetic domain is moved to a second stable position by a second cylindrical magnetic domain c.multidot.b formed by the irradiation of light beam or by a temperature gradient whereby stable recording, reading thereof and accurate calculation function can be carried out.

Abstract: A thermomagnetic recording method is capable of recording information on a layer of soft magnetic material which has an axis of easy magnetization normal to the surface of the layer and in which magnetic bubble domains are generated by application of a bias magnetic field. Information is recorded by radiating the layer with pulses of a focused beam so as to form a magnetic bubble domain having a magnetization opposite to a direction of the bias magnetic field. Recorded information is stable but can be easily erased.

Abstract: A magnetic domain device has at least one post element formed from a material that exhibits magnetic domain characteristics and that is positioned on a nonmagnetic substrate material. A pair of electrical drive lines associated with a post element permit coincident current selection of the post element to nucleate a magnetic domain reversal, and an additional current introduced into an adjacent drive line establishes an additive magnetic field to assist the propagation of a domain wall associated with the nucleated magnetic domain reversal so that the direction of magnetization of the post element is reversed.

Abstract: In a detector of an magnetic bubble memory device of the type comprising a magnetic bubble memory element having a detector, a source of constant current for passing constant current through the detector for producing a bubble output signal according to the magnetoresistive effect of a detector, a preamplifier for amplifying the output signal, a DC regenerator for regenerating an output signal of the preamplifier and a discriminator for converting the DC regenerated signal into a binary code, there is provided a holding circuit connected between the DC regenerator and the discriminator for holding a peak value of the DC regenerated signal for a predetermined time.

Abstract: This invention relates to a magneto-optical storage and playback process for travelling information carriers, by recording on a magnetizable information carrier (1) in the form of a tape, disc or roller while the carrier is in motion, said information carrier having information areas which are larger than 0.2 .mu.m and smaller than 20 .mu.m in one direction of the information plane, the process being carried out by the production of a geometrical structure (4) by the action of the magnetic fields of the recorded information on particles whose greatest length is less than 0.1 .mu.m, preferably 0.02 .mu.m, and by optical scanning of these structures in which light of wavelength 0.38 to 0.8 .mu.m is diffracted on the surface of the moving information carrier (1) and diffraction images are produced which serve for the interpretation of the information.

Abstract: A magnetic to optic transducer based upon magnetic bubble technology is provided. A magnetic sheet with a thin magnetic film guide pattern creating a bubble path thereon responds to external magnetic fields to position magnetic bubbles along the path. A varying magnetic field in the plane of the sheet displaces bubbles which are optically sensed by a fiber light conductor contacting both sides of the magnetic sheet at a location in the bubble path. A polarized light source transmits light through the fiber and a polarizing filter on one side of the magnetic sheet to a light detector on the other side of the sheet. The presence or absence of the magnetic bubble at the fiber position thereby affects the polarization of the light transmitted through the sheet and provides a detectable signal for reading the nature of the external magnetic field. The transducer may comprise permanent magnetic field generating means which do not require continuous energization.

Abstract: A small, highly reliable and inexpensive switching equipment, in which digital signals to be switched, stored as the presence or absence of magnetic domains in a first magnetic sheet or applied as the presence or absence of light to a flat plane formed by bundles of optical fibers, are switched by switching condition determining signals stored as the presence or absence of magnetic domains in a second magnetic sheet.

Abstract: A magnetic memory device in which information is stored in the form of strip domains in a layer of magnetic material supported by a layer of ferromagnetic material. The ferromagnetic material contains a pattern of alternately magnetized strips for sustaining a magnetic field periodically varying in a first coordinate direction and directed transverse to the domain layer. The device also includes a generator for receiving and converting data into configurations of the strip domains in the plate.

Abstract: A pick-up device for reading out information which has been recorded on a magnetic medium. The device comprises a substrate and a layer of soft magnetic material overlying a surface of the substrate, the easy axis or direction of magnetization being normal to the surface and the magnetic material having properties capable of having magnetic bubble domains generated and propagated therein, so that when the pick-up device is used to read out information from a magnetic medium, patterns of magnetic domains are formed in the layer of magnetic material corresponding to the patterns of the recorded information. Although the magnetic material is of the type capable of having magnetic bubble domains generated and propagated therein, there is no need to provide the usual bias field for maintaining the bubble domains or for providing domain-transport or domain-annihilating fields.

Abstract: A method and an apparatus for characterizing magnetic materials especially LPE garnet films for magnetic bubble memory applications are described. The method and apparatus comprises in the first embodiment passing monochromatic linearly polarized light through a magnetic film, under no applied external field (Ha=0) with a randomly oriented stripe domain structure to produce a single diffraction grating, then (1) the angle of the first order diffracted beam is deduced by directly comparing the currents produced by a linear position photodetector and an ordinary intensity photodetector and (2) next a magnetic field (Ha) is applied normal to the surface of the film and the field is increased until intensity of the second order diffraction beam is maximized. In the second embodiment of the method so that higher signals can be detected for the first order diffracted beam, the film is magnetized so that the stripe domain configuration is parallel and the foregoing steps followed.

Abstract: A method of and an apparatus for improving the selective positioning of single wall domains or bubble domains in a bubble domain memory system is disclosed. The method includes the use of slotted intersecting digit and word drive lines that form memory areas, each memory area being defined by the inside opposing edges of the slotted drive lines at each intersection. Each memory area has four quadrants, three of which are effectively optically blocked by an opaque shield--a bubble domain in the one unblocked quadrant provides the desired Faraday rotation of a plane polarized coherent light beam to generate a beamlet that is optically detected as a binary digital signal. The slotted drive lines are formed below the surface of the bubble domain supporting layer whereby the so-provided magneto static barriers prevent bubble domain sticking in a selected one quadrant of the four quadrants of the memory area and prevent bubble domain escape from the memory area itself.

Abstract: Magnetographic printing apparatus having scan magnetization of the recording surface. A bubble plate is provided adjacent the recording surface upon which bubble magnetic domains are propagated in a direction perpendicular to the direction of movement of the recording medium. A row of electromagnetic recording heads on the opposite side of the recording medium from the bubble plate are energized to produce a magnetic field which, when added to the magnetic field of the bubbles, is sufficiently high to cause magnetization of selected portions of the recording medium. In a second embodiment, a belt having magnetically permeable vanes mounted thereon is positioned on the side of the recording medium opposite the electromagnets. The vanes concentrate the magnetic field from the electromagnets to a sufficiently high value to magnetize the recording medium.

Abstract: A display arrangement including a source of polarized radiation; a magnetic material capable of supporting magnetic bubble domains in the path of the polarized beam, for producing a modulated beam; a device for representing an image encoded signal by means of the magnetic bubble domains; and a display device in the path of the modulated polarized beam for providing a visual display of the encoded image.