Specific Detail Of Recording Medium Patents (Class 369/13.35)
  • Patent number: 10109309
    Abstract: A heat-assisted magnetic recording (HAMR) medium includes a perpendicular magnetic recording layer (typically a chemically-ordered FePt alloy), a seed/thermal barrier layer (typically MgO) below the recording layer, and a heat-sink layer with anisotropic thermal conductivity below the seed/thermal barrier layer. The in-plane thermal conductivity of the heat-sink layer is greater than its out-of-plane thermal conductivity. The heat-sink layer may be selected from hexagonal boron nitride (h-BN), hexagonal graphite, and the 6H polytype of hexagonal silicon carbide (6H-SiC). If the heat-sink layer is h-BN, the h-BN layer is formed on a seed layer and has its c-axis oriented out-of-plane (substantially orthogonal to the surface of the medium substrate).
    Type: Grant
    Filed: September 1, 2017
    Date of Patent: October 23, 2018
    Assignee: Western Digital Technologies, Inc.
    Inventors: Pierre-Olivier Jubert, Kumar Srinivasan
  • Patent number: 10068829
    Abstract: A power-module substrate unit having at least one power-module substrate including one ceramic substrate, a circuit layer formed on one surface of the ceramic substrate, and a metal layer formed on another surface of the ceramic substrate, and a heat sink on which the metal layer of the power-module substrate is bonded, in which the metal layer is made of an aluminum plate having purity of 99.99 mass % or higher; the heat sink is made of an aluminum plate having purity of 99.90 mass % or lower; and the circuit layer has a stacking structure of a first layer made of an aluminum plate having the purity of 99.99 mass % or higher and being bonded to the ceramic substrate and a second layer made of the aluminum plate having the purity lower than 99.90 mass % and being bonded on a surface of the first layer.
    Type: Grant
    Filed: April 24, 2015
    Date of Patent: September 4, 2018
    Assignee: MITSUBISHI MATERIALS CORPORATION
    Inventors: Sotaro Oi, Tomoya Oohiraki
  • Patent number: 9786304
    Abstract: A method for fabricating a near-field transducer (NFT) for a heat assisted magnetic recording (HAMR) write apparatus is described. The HAMR write apparatus is coupled with a laser for providing energy and has a media-facing surface (MFS) configured to reside in proximity to a media during use. The method includes providing a stack on an underlayer. The stack includes an endpoint detection layer, an optical layer and an etchable layer. The optical layer is between the etchable and endpoint detection layers. The etchable layer is patterned to form a mask. A portion of the optical layer is removed. A remaining portion of the optical layer has a bevel at a bevel angle from the MFS location. The bevel angle is nonzero and acute. The NFT is provided such that the NFT has an NFT front surface adjoining the bevel and at the bevel angle from the MFS location.
    Type: Grant
    Filed: June 30, 2016
    Date of Patent: October 10, 2017
    Assignee: WESTERN DIGITAL (FREMONT), LLC
    Inventors: Shawn M. Tanner, Mingjun Yu, Min Zheng, Kyung Lee, Tsung Yuan Chen
  • Patent number: 8947987
    Abstract: Aspects of the present invention are directed to heat assisted magnetic recording (HAMR) media with a CoCrPtB based capping layer design that is capable of reducing switching field distribution and boosting signal-to-noise ratio of HAMR media. In one embodiment of the invention, a recording medium for heat assisted magnetic recording (HAMR) includes a substrate, a magnetic recording layer on the substrate, and a capping layer on and directly in contact with the magnetic recording layer. The capping layer includes CoCrPtB.
    Type: Grant
    Filed: July 1, 2013
    Date of Patent: February 3, 2015
    Assignee: WD Media, LLC
    Inventors: Bincheng Wang, Alexander S. Chernyshov, Hua Yuan, Tomoko Seki, Antony Ajan, B. Ramamurthy Acharya
  • Patent number: 8885447
    Abstract: An aspect of the present invention relates to glass for a magnetic recording medium substrate, which comprises essential components in the form of SiO2, Li2O, Na2O, and one or more alkaline earth metal oxides selected from the group consisting of MgO, CaO, SrO, and BaO wherein a molar ratio of a content of CaO to a combined content of MgO, CaO, SrO, and BaO (CaO/(MgO+CaO+SrO+BaO)) is equal to or less than 0.20, and which has a glass transition temperature of equal to or higher than 650° C.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: November 11, 2014
    Assignee: Hoya Corporation
    Inventors: Naomi Matsumoto, Kazuaki Hashimoto
  • Patent number: 8760980
    Abstract: Apparatus for recording data and method for making the same. In accordance with some embodiments, a magnetic recording layer is adapted to store data along perpendicular magnetic domains. A protective overcoat layer is formed on the magnetic recording layer to substantially protect the magnetic recording layer from environmental effects. The protective overcoat layer is made of carbon intermixed with at least one transition metal, such as but not limited to chromium.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: June 24, 2014
    Assignee: Seagate Technology LLC
    Inventors: Lihong Zhang, Samuel Gan
  • Patent number: 8724434
    Abstract: A magnetic recording system including follows: a recording head, a recording medium that includes a first recording medium layer, a second recording medium layer, and a substrate. The magnetic recording system includes an electric field applying device applying an electric field and a magnetic field applying device applying a magnetic field to the recording medium, a movement mechanism that moves them to an arbitrary position. The magnetic recording system has a function of controlling an applying direction of at least one of the electric field applying device and the magnetic field applying device, and the recording head is arranged at a position facing the recording medium.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: May 13, 2014
    Assignee: TDK Corporation
    Inventors: Mikio Matsuzaki, Koichi Shinohara, Tatsuo Shibata, Masashi Sahashi, Tomohiro Nozaki
  • Patent number: 8705326
    Abstract: A copy protection method includes the steps of providing an optical storage device having a substrate layer and a data structure layer coated on the substrate layer and containing a set of raw data codes; forming on the data structure layer at least one polarizing layer capable of causing a change in a light beam; and forming on the polarizing layer a scratch protection layer. The polarizing layer is located between the data structure layer and an optical reading device to influence a light beam irradiated thereon by the optical reading device, so that the set of raw data codes being optically accessed is conditionally converted into a different set of physical data codes. By providing the polarizing layer on the optical storage device to change the data codes that can be obtained by the optical reading device, it is able to stop illegal copying of the optical storage device.
    Type: Grant
    Filed: May 22, 2013
    Date of Patent: April 22, 2014
    Inventor: Ko Cheng Fang
  • Patent number: 8631561
    Abstract: The present invention generally relates to fabricating a bond pad for electrically connecting a laser diode to a slider and a TAR head in a HDD. The bond pad is deposited on a surface of the head that is perpendicular to the air bearing surface (ABS). The head is diced and lapped to expose the bond pad on a top surface of the head and mounted on a slider. The laser diode and a sub-mount may be coupled to the top surface of the slider—i.e., the surface opposite the ABS—by connecting to the bond pads. Specifically, both the laser diode and the sub-mount have electrodes thereon that are perpendicular to the bond pads. Conductive bonding material is used to bond the laser diode and the sub-mount to the bond pads.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: January 21, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Christian René Bonhôte, Linden James Crawforth, Toshiki Hirano, Fu-Ying Huang, Neil Leslie Robertson, Barry Cushing Stipe
  • Patent number: 8578593
    Abstract: A method of manufacturing a thermally-assisted magnetic write head is provided. The method includes steps of: forming a laminate structure including the waveguide; the plasmon generator, and the magnetic pole in order; performing a first polishing process to planarize an end surface of the laminate structure; performing a first etching process to remove impurity attached on the end surface of the laminate structure, and to allow the plasmon generator to be recessed from the waveguide and the magnetic pole, thereby forming a recessed region on the end surface of the laminate structure; forming a protection layer on the end surface of the laminate structure such that at least the recessed region is filled; and performing a second polishing process on the end surface of the laminate structure formed with the protection layer until the plasmon generator is exposed, thereby completing the air bearing surface.
    Type: Grant
    Filed: October 12, 2010
    Date of Patent: November 12, 2013
    Assignees: TDK Corporation, SAE Magnetics (H.K.) Ltd.
    Inventors: Kosuke Tanaka, Shinji Hara, Tsutomu Chou, Yasutoshi Fujita
  • Patent number: 8576672
    Abstract: A layer configured for use in a magnetic stack has electrical resistivity greater than about 5×10?8 ?m and thermal conductivity greater than about 1 W/mK. In some arrangements, the magnetic stack includes a substrate with the layer disposed over the substrate, a magnetic recording layer disposed over the layer, and a thermal resist layer disposed between the layer and the magnetic recording layer. In some arrangements, the layer is configured to function as a heat sink and a soft under layer. A system that incorporates the layer can include a magnetic write pole, a near field transducer (NFT) positioned proximate the write pole that radiates energy.
    Type: Grant
    Filed: May 25, 2012
    Date of Patent: November 5, 2013
    Assignee: Seagate Technology LLC
    Inventors: Chubing Peng, Edward Charles Gage, Ganping Ju, Jan-Ulrich Thiele, Kaizhong Gao
  • Patent number: 8472298
    Abstract: An optical information recording and reproducing apparatus includes an irradiation unit of a signal light beam and a reference light beam required for data recording, and a cure irradiation unit having at least one of a pre-cure irradiation that irradiates a predetermined light beam on to a desired position prior to irradiating the reference light bean and the signal light beam on to the desired position when information is recorded in the desired position on an optical information recording medium and a post-cure irradiation that irradiates a predetermined light beam on to the desired position so as to make the desired position non-recordable after the information is recorded in the desired position on the recording medium. The cure irradiation unit is disposed in one driving device in a freely movable manner in the driving device.
    Type: Grant
    Filed: June 2, 2009
    Date of Patent: June 25, 2013
    Assignee: Hitachi, Ltd.
    Inventor: Kenji Akahoshi
  • Patent number: 8441897
    Abstract: An optically-readable disk includes a device that disrupts readability of the disk when the disk is spun at an angular velocity substantially greater than required to play the disk in its intended playing device, or when a defined integral of velocity and time is exceeded. The device may include a fluid container that disperses a data-disruptive fluid. The device may include a membrane or layer that is disrupted when the disk is rotated above a defined angular velocity, or when a defined integral of velocity and time is exceeded. The device may include an electro-optical material that is activated by an electrical signal from a controller in response to an input from a sensor responsive to motion of the disk.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: May 14, 2013
    Inventor: Gary Stephen Shuster
  • Patent number: 8351845
    Abstract: A data receiving and recording method and data receiver are provided for receiving data coded by a predetermined method and copyright information attached to the data. While recording the received data on a predetermined recording medium, the copyright information is recorded into a predetermined area of the recording medium. Preferably, the data consists of audio data of the song, lyrics data of the song and image data relating to the song and the copyright information is allotted respectively to the audio data, lyrics data and image data.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: January 8, 2013
    Assignee: Sony Corporation
    Inventors: Shintaro Tsutsui, Susumu Nagano, Yasushi Katayama
  • Patent number: 8322022
    Abstract: A method for providing energy assisted magnetic recording (EAMR) heads is described. The method comprises bonding a plurality of lasers to a first substrate. The plurality of lasers corresponds to the plurality of EAMR heads and is for providing energy to a plurality of EAMR transducers. The method further comprises fabricating the plurality of EAMR transducers for the plurality of EAMR heads on a second substrate, bonding the first substrate to the second substrate such that the plurality of EAMR transducers and the plurality of lasers reside between the first substrate and the second substrate, removing at least one of the first substrate and the second substrate, and separating a remaining substrate into the plurality of EAMR heads.
    Type: Grant
    Filed: June 28, 2010
    Date of Patent: December 4, 2012
    Assignee: Western Digital (Fremont), LLC
    Inventors: Ge Yi, Hongxing Yuan, Ming Sun, Dujiang Wan
  • Patent number: 8259541
    Abstract: In optical recording and/or reproduction using an SIL optical system that performs a tilt servo using light for recording and/or reproduction, the SIL and an optical recording medium have a high probability of colliding with each other before the tilt servo is started. To prevent the collision, an optical recording/reproduction method performs a gap servo that controls a gap between a surface of an optical recording medium and a bottom surface of an SIL using reflected light that is generated from light traveling from the bottom surface of the SIL and reflecting on the optical recording medium, a focus servo that controls a distance between a focal point of the light and the bottom surface of the SIL, and a tilt servo that controls a tilt of the bottom surface of the SIL relative to the surface of the optical recording medium using the reflected light.
    Type: Grant
    Filed: February 24, 2009
    Date of Patent: September 4, 2012
    Assignee: Panasonic Corporation
    Inventors: Eiichi Ito, Masahiro Birukawa
  • Patent number: 8229270
    Abstract: An audio and video synchronization compensation method and apparatus for smoothly compensating audio and video synchronization in an audio and video system such as a DTV and a DVD player are provided. The apparatus includes a signal decoder unit which extracts time information for reproducing a video and/or audio signal and reference operation time information of a reproduction system from an input compressed stream; a signal synchronization control unit which determines the reproduction state of a signal by comparing reproduction time information of the stream with reference time information of the system, measures the difference between the reproduction time information and the reference time information in the determined signal reproduction state, and adjusts a transition speed used to approach from a signal reproduction interval to a signal synchronization interval according to a reproduction speed value of a pattern corresponding to the difference.
    Type: Grant
    Filed: February 20, 2007
    Date of Patent: July 24, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Seung-hoon Kim, Chang-yong Heo
  • Patent number: 8223598
    Abstract: An optically-readable disk includes a device that disrupts readability of the disk when the disk is spun at an angular velocity substantially greater than required to play the disk in its intended playing device, or when a defined integral of velocity and time is exceeded. The device may include a fluid container that disperses a data-disruptive fluid. The device may include a membrane or layer that is disrupted when the disk is rotated above a defined angular velocity, or when a defined integral of velocity and time is exceeded. The device may include an electro-optical material that is activated by an electrical signal from a controller in response to an input from a sensor responsive to motion of the disk.
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: July 17, 2012
    Inventor: Gary Stephen Shuster
  • Patent number: 8065786
    Abstract: Provided is a manufacturing method of heat-assisted magnetic recording head, in which a light source unit can be easily joined to a slider with sufficiently high accuracy, under avoiding the excessive mechanical stress. The manufacturing method comprises the steps of: moving relatively the light source unit and the slider, while applying a sufficient voltage between an upper electrode of the light source and an electrode layer provided in the slider; and setting the light source unit and the slider in desired positions in a direction perpendicular to the element-integration surface of the slider substrate. The desired positions are positions where the light source just emits due to a surface contact between: the protruded portion of the lower surface of the light source; and the upper surface of the electrode layer, which is a portion of the wall surface of a step formed on the head part.
    Type: Grant
    Filed: April 23, 2008
    Date of Patent: November 29, 2011
    Assignee: TDK Corporation
    Inventors: Koji Shimazawa, Yasuhiro Ito, Eiji Komura, Seiichi Takayama, Kosuke Tanaka
  • Patent number: 8068387
    Abstract: A magneto-optical device is disclosed that includes a non-magnetic support body and a fine particle arrangement layer on the non-magnetic support body. The fine particle arrangement layer includes multiple regularly arranged fine metal magnetic particles. In the magneto-optical device, magnetization is generated by applying an external magnetic field to the fine metal magnetic particles, and linearly polarized light is made incident on the fine metal magnetic particles, so that a magneto-optical effect is increased by the interaction between the incident light on the fine metal magnetic particles and the surface plasmon oscillation of the fine metal magnetic particles.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: November 29, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Tadao Katsuragawa
  • Publication number: 20110235480
    Abstract: A magnetic recording head comprises a write pole having a pole tip adjacent to an air bearing surface, a return pole, an optical near field transducer positioned adjacent the pole tip and an air bearing surface for exposing a portion of a magnetic storage medium to high energy radiation. The energy is directly provided to the near field transducer by a ridge waveguide with tapered coupling elements, by a two dimensional straight or curved waveguide with a beveled end with a metal/dielectric coating for delivering energy to the near field transducer, or by a curved waveguide. The waveguide with tapered coupling elements or with beveled end can be fabricated by means of conventional wafer processing.
    Type: Application
    Filed: March 29, 2010
    Publication date: September 29, 2011
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Arkadi Goulakov, Kaizhong Gao, Xuhui Jin
  • Patent number: 7974158
    Abstract: A small-sized, large-capacity optical disk is provided which is superior in portability. The optical disk has a diameter less than 64 mm and a thickness less than 0.8 mm. Tracks are formed with a pitch less than 0.6 ?m, and the record area is divided into a plurality of zones alone the radium. The optical disk can store more than 650 MB of compressed data.
    Type: Grant
    Filed: April 26, 2000
    Date of Patent: July 5, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takahashi Akira, Terashima Shigeo, Yamaoka Hideyoshi
  • Patent number: 7916581
    Abstract: An optically-readable disk includes a device that disrupts readability of the disk when the disk is spun at an angular velocity substantially greater than required to play the disk in its intended playing device, or when a defined integral of velocity and time is exceeded. The device may include a fluid container that disperses a data-disruptive fluid. The device may include a membrane or layer that is disrupted when the disk is rotated above a defined angular velocity, or when a defined integral of velocity and time is exceeded. The device may include an electro-optical material that is activated by an electrical signal from a controller in response to an input from a sensor responsive to motion of the disk.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: March 29, 2011
    Inventor: Gary Stephen Shuster
  • Patent number: 7804744
    Abstract: An optically-readable disk includes a device that disrupts readability of the disk when the disk is spun at an angular velocity substantially greater than required to play the disk in its intended playing device, or when a defined integral of velocity and time is exceeded. The device may include a fluid container that disperses a data-disruptive fluid. The device may include a membrane or layer that is disrupted when the disk is rotated above a defined angular velocity, or when a defined integral of velocity and time is exceeded. The device may include an electro-optical material that is activated by an electrical signal from a controller in response to an input from a sensor responsive to motion of the disk.
    Type: Grant
    Filed: July 3, 2008
    Date of Patent: September 28, 2010
    Inventor: Gary Stephen Shuster
  • Patent number: 7773086
    Abstract: Rendering with a punching mask is performed without voxelization. A plurality of sub-volumes are identified as a function of the punching mask. The sub-volumes are generally layered in range. Each sub-volume is rendered separately or independently. The renderings from multiple passes or sub-volumes are composited together.
    Type: Grant
    Filed: March 19, 2007
    Date of Patent: August 10, 2010
    Assignee: Siemens Medical Solutions USA, Inc.
    Inventors: Wei Li, Daphne Yu
  • Publication number: 20100097901
    Abstract: In a particular embodiment, an optical transducer includes at least three optically conductive blades arranged symmetrically about a center gap. The optical transducer is adapted to receive polarized light from a light source and to focus the polarized light onto a recording medium while conserving polarization of the polarized light.
    Type: Application
    Filed: October 16, 2008
    Publication date: April 22, 2010
    Applicant: Seagate Technology LLC
    Inventors: William Albert Challener, Julius Kurt Hohlfeld, Adnan Rebei
  • Publication number: 20100074062
    Abstract: Provided is a magnetic recording medium that generates near-field light within itself and enables favorable heat-assisted magnetic recording with this near-field light. The medium comprises: a magnetic recording layer; and an optically changeable layer formed on the opposite side to a substrate relative to the magnetic recording layer, the optically changeable layer being made transparent or a refractive index of the layer being changed when irradiated by light with an intensity not less than a predetermined intensity. By the irradiation, a minute opening or a refractive-index-changed area is formed within the irradiated portion on the optically changeable layer. The light irradiation onto the minute opening or the refractive-index-changed area enables near-field light to be generated, which heats a portion of the magnetic recording layer. Thus, the anisotropic field of the portion is lowered to a writable value, which enables heat-assisted magnetic recording by applying write field.
    Type: Application
    Filed: September 19, 2008
    Publication date: March 25, 2010
    Applicant: TDK Corporation
    Inventors: Akifumi Kamijima, Koji Shimazawa
  • Publication number: 20090274016
    Abstract: A magneto-optical device is disclosed that includes a non-magnetic support body and a fine particle arrangement layer on the non-magnetic support body. The fine particle arrangement layer includes multiple regularly arranged fine metal magnetic particles. In the magneto-optical device, magnetization is generated by applying an external magnetic field to the fine metal magnetic particles, and linearly polarized light is made incident on the fine metal magnetic particles, so that a magneto-optical effect is increased by the interaction between the incident light on the fine metal magnetic particles and the surface plasmon oscillation of the fine metal magnetic particles.
    Type: Application
    Filed: December 27, 2006
    Publication date: November 5, 2009
    Inventor: Tadao Katsuragawa
  • Patent number: 7577079
    Abstract: The present invention provides a master disk with high flexibility and high close contact property with a slave disk to be transferred, which bears information to be transferred by magnetic transfer. When incident angle of X-ray is designated by ?, electroforming is performed such that X-ray diffraction pattern of the master substrate 11 has a 200 plane reflection at 2?=51.0° to 53.0°, and a 220 plane reflection at 2?=75.5° to 76.5°, and the reflection intensity ratio of X-ray diffraction of the 220 plane with respect to the 200 plane is I[220]/I[200]=2 to 30.
    Type: Grant
    Filed: March 17, 2006
    Date of Patent: August 18, 2009
    Assignee: FUJIFILM Corporation
    Inventors: Shiho Kamisawa, Kenji Ichikawa
  • Patent number: 7539110
    Abstract: An optical information recording medium for recording information by a plurality of record mark lengths, wherein the shortest mark length is at most 0.5 ?m, and a crystal state is an unrecorded or erased state and an amorphous state is a recorded state, wherein the erasing is carried out by recrystallization which substantially proceeds by crystal growth from an interface between the amorphous portion or a melt portion and a peripheral crystal portion; and an optical recording method suitable therefore. The medium of the present invention has characteristics that overwriting can be made at a high speed, the jitter of mark edge is small, mark length modulation recording can be made at a high density, and the formed mark is excellent in the stability with the lapse of time.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: May 26, 2009
    Assignee: Mitsubishi Kagaku Media Co., Ltd.
    Inventors: Hironobu Mizuno, Takashi Ohno, Michikazu Horie
  • Publication number: 20090129213
    Abstract: The present invention provides a magnetooptic device, a magnetooptic head, and a magnetic disk drive each capable of performing optically assisted magnetic recording and each having a small size, improved recording density, and a higher transfer rate. In a magnetooptic device, a magnetic circuit including a magnetic gap and a thin film magnetic transducer having a coil portion are stacked on the surface of a semiconductor laser. By the arrangement, optically assisted magnetic recording can be performed, small size and light weight are achieved, and higher transfer rate can be implemented.
    Type: Application
    Filed: December 23, 2008
    Publication date: May 21, 2009
    Applicant: FUJI XEROX CO., LTD.
    Inventor: Kiichi Ueyanagi
  • Patent number: 7532555
    Abstract: In an optical recording method used when information is recorded in a phase-change recording layer of a large-capacity rewritable optical recording medium such as a DVD-RW, one block pulse is used as a recording pulse for forming one recording mark when a recording velocity is higher than a recording linear velocity at which the rewritable optical recording medium can be rewritten, whereas a pulse train comprised of a plurality of short pulses is used as the recording pulse for forming one recording pulse when the recording velocity is within recording linear velocities at which the rewritable optical recording medium can be rewritten, whereby high-velocity recording is realized.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: May 12, 2009
    Assignee: Mitsubishi Kagaku Media Co., Ltd.
    Inventors: Masaaki Mizuno, Hiroyuki Hoshino, Takashi Ohno, Michikazu Horie
  • Publication number: 20090097365
    Abstract: Provided are a magnetic layer, a method of forming the magnetic layer, an information storage device, and a method of manufacturing the information storage device. The information storage device may include a magnetic track having a plurality of magnetic domains, a current supply element connected to the magnetic layer and a reading/writing element. The magnetic track includes a hard magnetic track, and the hard magnetic track has a magnetization easy-axis extending in a direction parallel to a width of the hard magnetic track.
    Type: Application
    Filed: February 29, 2008
    Publication date: April 16, 2009
    Inventors: Sung-chul Lee, Sun-ae Seo, Young-Jin Cho, Kwang-seok Kim
  • Publication number: 20090073817
    Abstract: An optically-readable disk includes a device that disrupts readability of the disk when the disk is spun at an angular velocity substantially greater than required to play the disk in its intended playing device, or when a defined integral of velocity and time is exceeded. The device may include a fluid container that disperses a data-disruptive fluid. The device may include a membrane or layer that is disrupted when the disk is rotated above a defined angular velocity, or when a defined integral of velocity and time is exceeded. The device may include an electro-optical material that is activated by an electrical signal from a controller in response to an input from a sensor responsive to motion of the disk.
    Type: Application
    Filed: July 3, 2008
    Publication date: March 19, 2009
    Inventor: Gary Stephen Shuster
  • Publication number: 20080259743
    Abstract: The present invention relates to a method, apparatus and record carrier for controlling read-out and/or synchronization between an external magnetic field and written data during a reading operation from a magneto-optical recording medium comprising a storage layer and a read-out layer. An expanded domain leading to a pulse in a reading signal is generated in said read-out layer by copying a mark region from said storage layer to said read-out layer upon heating by a radiation power and with the help of the external magnetic field. The waveform of the reading signal is analyzed, and the analyzing result is used for correcting a phase deviation and/or for controlling a copy window size of the mark copying. Thereby, phase errors can be corrected for any size of the copy window. Even small changes in the copy window can be detected and corrected.
    Type: Application
    Filed: March 3, 2008
    Publication date: October 23, 2008
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS, N.V.
    Inventor: COEN ADRIANUS VERSCHUREN
  • Patent number: 7420888
    Abstract: An optical recording medium 10 on which recording/reproducing or reproducing is performed by irradiating a light by means of an objective lens 4 having a numerical aperture equal to or more than 1 wherein an optical recording portion 2 is provided at least at the outer most surface at the irradiation side of the optical recording medium 10 and a relation n?NA is selected when the refractive index of the recording portion 2 is n and the numerical aperture of the objective lens 4 is NA. Accordingly, it can propose an optical recording medium and an optical recording/reproducing method suitable for a near-field optical recording method which uses an objective lens having a numerical aperture equal to or more than 1.
    Type: Grant
    Filed: June 19, 2003
    Date of Patent: September 2, 2008
    Assignee: Sony Corporation
    Inventors: Masataka Shinoda, Kimihiro Saito
  • Patent number: 7414924
    Abstract: An optical disk that includes main information and write-once information recorded on the optical disk. The write-once information is recorded as information unique to the optical disk, and the write-once information stores at least watermark production parameters for producing a watermark.
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: August 19, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mitsuaki Oshima, Shinichi Konishi, Shin-ichi Tanaka, Kenji Koishi, Mitsurou Moriya, Yoshiho Gotoh, Yoshinari Takemura, Norio Miyatake, Motoyoshi Murakami
  • Publication number: 20080074959
    Abstract: A write head for use in a bistable, magnetic optical display comprising one or more conducting coils configured to generate a magnetic field that is substantially perpendicular to the axis of rotation of one or more magneto optical elements of the optical display and parallel to a display viewing plane of the one or more magnetic display elements of the magnetic optical display such that an electrical pulse of less then 150 milliseconds is sufficient to create a magnetic field that alters the bistable state of the magneto optical display such that the display will stay in this new state without the need for ongoing electrical current being applied to the write head.
    Type: Application
    Filed: September 27, 2007
    Publication date: March 27, 2008
    Applicant: TRED Displays Corporation
    Inventors: Charles O. Edwards, James Caruso
  • Patent number: 7313056
    Abstract: The magneto-optical recording medium is comprised of a phase pit substrate/dielectric layer/recording layers/dielectric layer/reflection layer and a ROM and RAM can be simultaneously regenerated. The shape of the phase pit is constructed to be 5<100×Ip/Im<22 where Im is a reflection level on the mirror face and Ip is a phase pit signal output of the shortest mark when a regeneration light having polarization in a direction horizontal to the track direction of the medium is irradiated. Since the jitter of both the magneto-optical recording/regeneration signals and phase pit signals can be suppressed within an optimum range, the quality of the regeneration signals when ROM and RAM are simultaneously regenerated can be improved.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: December 25, 2007
    Assignee: Fujitsu Limited
    Inventor: Tetsuo Hosokawa
  • Publication number: 20070237038
    Abstract: Rendering with a punching mask is performed without voxelization. A plurality of sub-volumes are identified as a function of the punching mask. The sub-volumes are generally layered in range. Each sub-volume is rendered separately or independently. The renderings from multiple passes or sub-volumes are composited together.
    Type: Application
    Filed: March 19, 2007
    Publication date: October 11, 2007
    Applicant: Siemens Corporate Research, Inc.
    Inventors: Wei Li, Daphne Yu
  • Patent number: 7277619
    Abstract: This invention relates to a method for forming a nano-imprinted photonic crystal waveguide, comprising the steps of: preparing an optical film on a substrate; preparing a template having a plurality of protrusions of less than 500 nm in length such that the protrusions are spaced a predetermined distance from each other; heating the film; causing the template to press against the heated film such that a portion of the film is deformed by the protrusions; separating the template from the film; and etching the film to remove a residual layer of the film to form a nano-imprinted photonic crystal waveguide.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: October 2, 2007
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: James E. Ellenson, Timothy S. Hostetler, William M. Tong
  • Patent number: 7251202
    Abstract: A substrate for an optical recording medium includes recording tracks formed in guide grooves on a disc and an address section having an address pit sequence formed between the recording tracks in the guide grooves along an information reading direction of the recording tracks. The recording tracks in the guide grooves are divided into a prescribed number of zones. In each of the zones, the center of the address section corresponding to a recording track in the radially outermost or radially innermost guide groove is disposed so as to shift in a radial direction of the disc in relative relationship to the center of the recording track in the guide groove.
    Type: Grant
    Filed: August 4, 2003
    Date of Patent: July 31, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kenichi Nishiuchi, Shigeaki Furukawa, Tetsuya Akiyama
  • Patent number: 7110346
    Abstract: Techniques and devices based on near-field second surface recording.
    Type: Grant
    Filed: December 23, 2004
    Date of Patent: September 19, 2006
    Assignee: TernStor Corporation
    Inventor: Roger A. Hajjar
  • Patent number: 7102990
    Abstract: An optical information-recording medium comprises (a) a disk-shaped substrate having a first main surface and a second main surface opposite to the first main surface; an incidence surface of the medium being located to be nearer to the first main surface than the second main surface; (b) a recording layer formed on the substrate; and (c) a signal generation layer formed on the substrate in such a way as to be nearer to the incident surface than the recording layer. The signal generation layer allows an incident light beam irradiated to the incidence surface to pass through and allows a reflected light beam from the recording layer to pass through. The signal generation layer includes a transmittance changing region having a transmittance with respect to the incident light beam different from its neighborhood, thereby generating a repeated transmittance change according to rotation of the medium.
    Type: Grant
    Filed: April 2, 2002
    Date of Patent: September 5, 2006
    Assignee: NEC Corporation
    Inventor: Mitsuya Okada
  • Patent number: 6996052
    Abstract: An optical information recording medium for recording information by a plurality of record mark lengths, wherein the shortest mark length is at most 0.5 ?m, and a crystal state is an unrecorded or erased state and an amorphous state is a recorded state, wherein the erasing is carried out by recrystallization which substantially proceeds by crystal growth from an interface between the amorphous portion or a melt portion and a peripheral crystal portion; and an optical recording method suitable therefore. The medium of the present invention has characteristics that overwriting can be made at a high speed, the jitter of mark edge is small, mark length modulation recording can be made at a high density, and the formed mark is excellent in the stability with the lapse of time.
    Type: Grant
    Filed: September 8, 1999
    Date of Patent: February 7, 2006
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Hironobu Mizuno, Takashi Ohno, Michikazu Horie
  • Patent number: 6985373
    Abstract: An element for steering electromagnetic beams. The element includes a phase change material in combination with dielectric and other layers in a multilayer optical stack. The phase change material that is reversibly transformable between two or more structural states, where different structural states differ with respect to refractive index and/or extinction coefficient. The structural state of the phase change material establishes a phase angle state for the element that dictates the direction of propagation of an output beam produced from an incident electromagnetic beam. Depending on the structural state, the element adopts one of two principal phase angle states and a binary beam steering capability is achieved in which an incident electromagnetic beam can be redirected in either of two directions. In a preferred embodiment, the output beam is a reflected beam and the element includes a phase change material sandwiched between two dielectric materials and supported by a metal layer.
    Type: Grant
    Filed: July 27, 2004
    Date of Patent: January 10, 2006
    Assignee: Energy Conversion Devices, Inc.
    Inventor: David Tsu
  • Patent number: 6882460
    Abstract: An element for reflecting, transmitting, focusing, defocusing or wavefront correction of electromagnetic radiation in the terahertz frequency range. The elements include a grid of conductive strips including active regions comprising a chalcogenide phase change material. The chalcogenide material can be in an amorphous, crystalline or partially crystalline state. The dispersive characteristics of the grid (e.g. impedance, admittance, capacitance, inductance) influence one or more of the reflection, transmission, state of focusing or wavefront characteristics of incident electromagnetic radiation through the action of a stored phase taper formed by establishing a crystallinity gradient over a series of active chalcogenide regions or domains in one or more directions of the element.
    Type: Grant
    Filed: September 25, 2003
    Date of Patent: April 19, 2005
    Assignee: Energy Conversion Devices, Inc.
    Inventors: David Tsu, Robert O. Miller
  • Patent number: 6839306
    Abstract: A near-filed optical storage technique based on the “second surface” recording, where the optical storage medium is designed to have the recording layer formed between the reflective layer and the optically transparent substrate, and optical head and the medium maintain the near-filed configuration to achieve a numerical aperture greater than unity at the recording layer.
    Type: Grant
    Filed: July 30, 2001
    Date of Patent: January 4, 2005
    Assignee: TeraStar Corporation
    Inventor: Roger A. Hajjar
  • Publication number: 20040240327
    Abstract: A patterned magnetic recording medium for use in heat assisted magnetic recording comprises an electrically conductive heat sink layer and a plurality of discrete magnetic recording elements positioned adjacent to a first surface of the heat sink layer. Disc drives that include the patterned medium and a method of magnetic recording using the patterned media are also included.
    Type: Application
    Filed: May 29, 2003
    Publication date: December 2, 2004
    Applicant: Seagate Technology LLC
    Inventors: Ibrahim Kursat Sendur, William Albert Challener, Chubing Peng
  • Patent number: RE42824
    Abstract: A magneto-optical device including a substrate which is transparent to light in a visible spectrum region and, a plurality of ferromagnetic layers arranged thereon, each ferromagnetic layer preferably having a width ranging from in an inclusive range of 5 to through 100 nanometers and a thickness ranging from in an inclusive range of 0.1 to through 5 microns. The, wherein said ferromagnetic layers are parallel to each other and separated by a distance ranging from in an inclusive range of 0.2 to through 2 microns. The ferromagnetic layers are arranged preferably on the side walls of grooves formed parallel to each other in the transparent substrate.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: October 11, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Tadao Katsuragawa