Abstract: A data storage device is disclosed comprising a coarse actuator configured to actuate a first head over a first disk surface and a second head over a second disk surface. A first fine actuator is configured to actuate the first head over the first disk surface, and a second fine actuator is configured to actuate the second head over the second disk surface. A first bias signal is calibrated for the first fine actuator, and a second bias signal is calibrated for the second fine actuator. The first fine actuator is controlled based on the first bias signal and the second fine actuator is controlled based on the second bias signal in order to concurrently access the first disk surface and the second disk surface.

Abstract: The present disclosure generally relates to semiconductor detectors for use in optoelectronic devices and integrated circuit (IC) chips, and methods for forming same. More particularly, the present disclosure relates to integration of semiconductor detectors with Bragg reflectors. The photodetector of the present disclosure includes a substrate, a Bragg reflector disposed on the substrate, and a semiconductor detector disposed on the Bragg reflector. The Bragg reflector includes alternating layers of a semiconductor material and a dielectric material.

Abstract: A method and a system for producing a change in a medium. The method places in a vicinity of the medium at least one energy modulation agent. The method applies an initiation energy to the medium. The initiation energy interacts with the energy modulation agent to directly or indirectly produce the change in the medium. The system includes an initiation energy source configured to apply an initiation energy to the medium to activate the energy modulation agent.

Abstract: A maximum write duration is determined for first and second heat-assisted write transducers of a data storage device. Exceeding the duration results in thermal degradation of the first and second write transducers. A request to write data to a heat-assisted recording medium is received. In response to a time to fulfill the request exceeding the maximum write duration, the data is divided into portions such that a respective writing of each of the portions does not exceed the maximum write duration. Writing successive ones of the portions to the heat-assisted recording medium involves alternating between the first and second write transducers.

Abstract: A light delivery system in a slider includes a channel waveguide, a mode-index refractive surface, a solid immersion mirror, and a near field transducer. The mode-index refractive surface shapes the angular spectrum of the light on its path to the solid immersion mirror in a manner so as to change the distribution of light energy focused on to the near field transducer.

Abstract: Apparatus and method for light source power control during the writing of data to a storage medium. In accordance with various embodiments, a data recording head is provided having a magnetic transducer and a light source. The light source is driven at a first power level to irradiate an adjacent storage medium prior to the writing if data to the medium using the magnetic transducer. The first power level is insufficient to alter a magnetization state of the medium. The light source is subsequently transitioned to a higher, second power level to irradiate the storage medium during the writing of data to said medium using the magnetic transducer, the second power level being sufficient to alter said magnetization state of the medium.

Abstract: A near-field transducer (NFT) has a primary tip that concentrates the oscillating charge of the NFT onto a substrate, such as magnetic recording medium, to heat regions of the medium, and a secondary tip. The secondary tip is located close to a temperature sensor, such as an electrical conductor whose resistance varies with temperature. The temperature sensor senses heat from the secondary tip and thus properties of the substrate like surface topography and the presence or absence of metallic material. The NFT can be part of a bit-patterned media (BPM) thermally-assisted recording (TAR) disk drive. The temperature sensor output is used to control the write pulses from the disk drive's write head so the magnetic write field is synchronized with the location of the magnetic data islands.

Abstract: An apparatus and associated method for a head gimbal assembly for data transduction in a data storage device with a heat assist laser. Various embodiments of the present invention are generally directed to a slider supporting at least a transducing element on an air bearing surface (ABS) and a laser assembly directly attached to a top side of the slider opposite the ABS. The laser assembly is positioned on the top side with no portion of the laser assembly extending past a longitudinal centerline of the slider.

Abstract: The present invention discloses a multilevel recording method and system thereof. The multilevel recording method applied to a recording media comprises the following steps. At First, a plurality of beams are provided to a recording layer of the recording media, and the recording layer has a first structure and a second structure. Then, a first polarized reflected light of the first structure and a second polarized reflected light of the second structure are detected by a detecting unit. Then, a corresponding table is stored by a storing unit. The corresponding table comprises a relationship between the different angle of the polarized reflected light and a level of multilevel recording. Finally, the processing unit looks up the corresponding table to process multilevel recording.

Abstract: The present invention discloses a multilevel recording method and system thereof. The multilevel recording method applied to a recording media comprises the following steps. At First, a plurality of beams are provided to a recording layer of the recording media, and the recording layer has a first structure and a second structure. Then, a first polarized reflected light of the first structure and a second polarized reflected light of the second structure are detected by a detecting unit. Then, a corresponding table is stored by a storing unit. The corresponding table comprises a relationship between the different angle of the polarized reflected light and a level of multilevel recording. Finally, the processing unit looks up the corresponding table to process multilevel recording.

Abstract: An optical head is provided with a light source for emitting a first laser beam having a first wavelength shorter than 430 nm, a two-wavelength light source for emitting a second laser beam having a second wavelength equal to or longer than 430 nm, a flat beam splitter in the form of a single plate for reflecting the first laser beam emitted from the light source, a wedge prism in the form of a single plate for reflecting the first laser beam reflected by the flat beam splitter and transmitting the second laser beam emitted from the two-wavelength light source, and an objective lens for focusing the first laser beam reflected by the wedge prism on an information recording surface of a BD. The light source is arranged such that the optical axis of the first laser beam emitted from the light source is inclined with respect to that of the second laser beam emitted from the two-wavelength light source. By this construction, the miniaturization of the optical head can be realized.

Abstract: An optical pickup for recording a hologram by using an angle multiplexing method. An optical beam is separated into two beams, a signal beam and a reference beam having different convergence/divergence degrees, by using an optical component such as a diffraction lens. The signal and reference beams are made incident upon the same objective, and the optical component or the objective lens is moved in a direction perpendicular to an optical axis, to thereby realize angle multiplex recording. If an optical information recording medium is inclined, the optical component or the objective lens is moved along the direction along which the optical information recording medium moved to change an angle of the reference beam incident upon the optical information recording medium and compensate for degradation of a reproduction signal.

Abstract: The present invention relates generally to the storage of information on magnetic and/or optical storage media by using one or more novel approaches alone or in combination. These novel approaches are capable of using at least one code which may comprise more than two values (i.e., more than a “0” and a “1”). A first series of approaches for the storage of information applies generally to optical storage/retrieval systems (e.g., CD's, DVD's, etc.); while a second series of approaches applies generally to electric and/or magnetic storage/retrieval systems (e.g., magnetic, magneto-optic, etc.). Each series of approaches is capable of storing information in one or more codes, wherein such approaches permit, if desired, the use of at least one higher order code which is different from the traditional binary code of “0's” and “1's” currently utilized for the storage of digital information.

Abstract: The present invention relates generally to the storage and/or retrieval of information on magnetic storage media by using one or more novel approaches alone or in combination. These novel approaches are capable of using at least one code which may comprise more than two values (i.e., more than a “0” and a “1”). A series of approaches applies generally to existing electric and/or magnetic storage/retrieval systems (e.g., magnetic, magneto-optic, etc.) as well as other novel electrical/magnetic systems. Each series of approaches is capable of storing information in one or more codes, wherein such approaches permit, if desired, the use of at least one higher order code which is different from the traditional binary code of “0's” and “1's” currently utilized for the storage of digital information.

Abstract: An optical data storage system writes or reads information with respect to an optical storage medium using an optical pickup including a solid immersion optical system or a solid immersion lens for generating a near-field and emitting a light beam. The optical storage medium includes a recording layer which is formed on a surface of an optical transmissive layer opposite to another surface of the optical transmissive layer which opposes the solid immersion optical system or solid immersion lens. The thickness of the optical transmissive layer is larger than one wavelength of the light beam. The interval between the surfaces of the solid immersion lens or solid immersion optical system and the optical transmissive layer is smaller than one wavelength of the light beam. Thus, the light beam reflected from the inside of an air gap and the inside of the optical storage medium between the air gap and the recording layer does not function as noise with respect to the light reflected from the recording layer.

Abstract: The invention relates generally to store information on magnetic or optical storage media by using one or more novel approaches alone or in combination. These novel approaches are capable of using at least one code which may comprise more than two values (FIG. 4d, 43). A first series of approaches for the storage of information applies generally to optical recording and reproducing system (FIGS. 7-10, optical media 66), while a second series of approaches applies generally to electric or magnetic recording and reproducing systems (FIG. 1-2, magnetic medium 1), Each series of approaches is capable of storing information data in one or more codes (FIG. 4d, 42a, 42b, 42c, 42d) and the use of at least one higher order code which is different from the traditional binary code of “0” and “1”.

Abstract: A method of reading out data from a domain expansion data storage such as a MAMMOS magneto-optic disk (1) which includes a data storage layer in which data is stored in the form of magnetic marks, and an expansion layer capable of copying and expanding domains from the storage layer, the system applying a first radiation beam (7), having a first spot size on the disk, in order to initiate copying of a domain from the storage layer to the expansion layer, and applying a second radiation beam (9), having a second spot size larger than the first spot size on the disk, in order to read out data from the expansion layer.

Abstract: An optical data storage system writes or reads information with respect to an optical storage medium using an optical pickup including a solid immersion optical system or a solid immersion lens for generating a near-field and emitting a light beam. The optical storage medium includes a recording layer which is formed on a surface of an optical transmissive layer opposite to another surface of the optical transmissive layer which opposes the solid immersion optical system or solid immersion lens. The thickness of the optical transmissive layer is larger than one wavelength of the light beam. The interval between the surfaces of the solid immersion lens or solid immersion optical system and the optical transmissive layer is smaller than one wavelength of the light beam. Thus, the light beam reflected from the inside of an air gap and the inside of the optical storage medium between the air gap and the recording layer does not function as noise with respect to the light reflected from the recording layer.

Abstract: A magneto-optical recording medium has magneto-optical recording layers (11, 12, 13) and reproducing layers (21, 22, 23). The information recorded in the reproducing layers are reproduced by means of reproducing light beams (31, 32, 33) of different wavelengths, respectively. In reproduction, magnetic domains (4) recorded in the recording layers are transferred in the reproducing layers formed on the respective recording layers, the transferred magnetic domains (5) are enlarged with an external magnetic field, and the information is reproduced. Since information is recorded and reproduced for each recording layer, the recording density is improved. Further since the reproduction signals are amplified by the magnetic domain enlargement, the C/N is improved.

Abstract: An optical data storage system writes or reads information with respect to an optical storage medium using an optical pickup including a solid immersion optical system or a solid immersion lens for generating a near-field and emitting a light beam. The optical storage medium includes a recording layer which is formed on a surface of an optical transmissive layer opposite to another surface of the optical transmissive layer which opposes the solid immersion optical system or solid immersion lens. The thickness of the optical transmissive layer is larger than one wavelength of the light beam. The interval between the surfaces of the solid immersion lens or solid immersion optical system and the optical transmissive layer is smaller than one wavelength of the light beam. Thus, the light beam reflected from the inside of an air gap and the inside of the optical storage medium between the air gap and the recording layer does not function as noise with respect to the light reflected from the recording layer.

Abstract: A driving circuit for a magnetic head that is used for modulating magnetic field in a magneto-optical disk drive is provided, which reduces power consumption even if the magnetic head has large inductance. The driving circuit comprises a switching circuit for generating pulse-like drive current in synchronization with a timing for applying a pulse of light in accordance with a space between pits to be recorded on a magneto-optical disk, and a conversion circuit for converting the pulse-like drive current into sine-wave current to be supplied to the magnetic head such that the maximum magnetic field can be obtained at the timing for applying a pulse of light.

Abstract: An optical disk recording method of recording data on an optical disk by applying laser light to a track of the optical disk, includes the steps of a) driving a plurality of laser light sources in sequence in a time division manner, and applying a light flux to one track of the optical disk successively, and b) producing a plurality of rows of record marks in the one track.

Abstract: An optical head includes a lens carrier movable at least radially of a magneto-optical disk in facing relation thereto. An object lens is mounted on the lens carrier to converge a laser beam for forming a laser spot on the disk. The object lens has an optical axis and includes a lens surface directed toward the disk. A patterned coil is formed on the lens surface at least in one layer and has a light-passing opening corresponding to the optical axis of the object lens. A light-pervious layer is formed on the lens surface for closing the light-passing opening of the coil.

Abstract: A magneto-optical recording medium has magneto-optical recording layers (11, 12, 13) and reproducing layers (21, 22, 23). The information recorded in the reproducing layers are reproduced by means of reproducing light beams (31, 32, 33) of different wavelengths, respectively. In reproduction, magnetic domains (4) recorded in the recording layers are transferred in the reproducing layers formed on the respective recording layers, the transferred magnetic domains (5) are enlarged with an external magnetic field, and the information is reproduced. Since information is recorded and reproduced for each recording layer, the recording density is improved. Further since the reproduction signals are amplified by the magnetic domain enlargement, the C/N is improved.

Abstract: A reproducing apparatus for a magneto-optical recording medium has, at one end of a swing arm, a magneto-optical head provided with a slider and a solid immersion lens. A reproducing light beam-detecting system is installed to the other end of the swing arm. During reproduction on a magneto-optical recording medium, an alternating magnetic field is applied while radiating a reproducing light beam which is power-modulated to have a low power and a high power in synchronization with a reproducing clock. The reproducing light beam having the low power causes transfer of a magnetic domain in the information-recording layer to the reproducing layer and magnification thereof. The reproducing light beam having the high power extinguishes the magnified magnetic domain. Minute magnetic domains can be individually reproduced at high C/N.

Abstract: An optical disk recording method of recording data on an optical disk by applying laser light to a track of the optical disk, includes the steps of a) driving a plurality of laser light sources in sequence in a time division manner, and applying a light flux to one track of the optical disk successively, and b) producing a plurality of rows of record marks in the one track.

Abstract: An object of the present invention is to make it possible to record information on an optical information recording medium in the form of three dimensional interference patterns so that the information is erasable in part.

Abstract: A magnetic head is configured of a core and a coil wound around the core and passing current through the coil in a variable direction allows the core to have an edge generating an alternating magnetic field Hex1 and another edge generating an alternating magnetic field Hex2. Alternating magnetic fields Hex1 and Hex2 are applied to the respective edges. Furthermore, a laser beam LB1 is directed such that its optical axis L01 matches the edge receiving the alternating magnetic field Hex1, and a laser beam LB2 is directed such that its optical axis L02 matches the edge receiving the alternating magnetic field Hex2. A first magneto-optical signal detected through the alternating magnetic field Hex1 and the laser beam LB1 and a second magneto-optical signal detected through the alternating magnetic field Hex2 and the laser beam LB2 are composited together.