Takekuma
Akira Takekuma, Tokyo JP
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20080217642 | LIGHT EMITTING DIODE WITH A STEP SECTION BETWEEN THE BASE AND THE LENS OF THE DIODE - [Problem to be Solved]It is to be made easy to arrange light emitting diodes, each including a lens having a hemispherical light emitting surface, and cover the base of the light emitting diodes with resin material. | 09-11-2008 |
Ikuko Takekuma, Kanagawa JP
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20090073599 | Perpendicular magnetic recording medium and magnetic recording and reproducing apparatus using the same - Embodiments of the present invention provide a perpendicular magnetic recording medium suitable for high density recording. According to one embodiment, a magnetic recording layer comprises four layers in which a first magnetic layer, a magnetic coupling layer, a second magnetic layer, and a third magnetic layer are formed above a substrate. The first magnetic layer and the second magnetic layer are perpendicular magnetization films containing an oxide, and ferromagnetically coupled with each other by way of the magnetic coupling layer, and they are, more preferably, a Co alloy layer containing an oxide. The third magnetic layer is ferromagnetically coupled with the second magnetic layer. The concentration of the oxide contained in the third magnetic layer is lower than the concentration of the oxide in the second recording layer, or the third magnetic layer does not contain the oxide. In this case, magnetic property is set for the anisotropic magnetic field Hk1 of the first magnetic layer and the anisotropic magnetic field Hk2 of the second magnetic layer, so as to satisfy: Hk1>Hk2. | 03-19-2009 |
20090116137 | Perpendicular magnetic recording medium and magnetic storage apparatus using the same - Embodiments of the present invention provide a perpendicular magnetic recoding medium capable of decreasing exchange coupling between crystal grains while suppressing increase in the crystal grain size of the magnetic recording layer. According to one embodiment, a perpendicular magnetic recoding medium is formed by stacking a seed layer, an intermediate layer, a magnetic recording layer, and a protecting layer all above a substrate. The magnetic recording layer has a granular structure constituted of a plurality of columnar grains comprising a CoCrPt alloy and a grain boundary containing an oxide. The seed layer is formed by stacking a first seed layer, a second seed layer, and a third seed layer in which the first seed layer comprises Ti or Ti alloy having a hexagonal close-packed structure, the second seed layer comprises Cu, Ag, or Al having a face-centered cubic structure or an alloy containing at least one element selected therefrom, and the third seed layer comprises an Ni alloy having a face-centered cubic structure. | 05-07-2009 |
20090195924 | Perpendicular magnetic recording medium and magnetic recording/reproducing apparatus using the same - Embodiments of the present invention help allow accurate control of the magnetization reversal in a magnetic recording layer in small reversal units, whereby high-density recording can be achieved. According to one embodiment, by forming an intermediate layer having a granular structure similar to that of the magnetic recording layer below the magnetic recording layer, a continuous crystal grain boundary is formed at the interface between the magnetic recording layer and the intermediate layer, thereby preventing incomplete formation of the crystal grain boundary found in the initial growth layer of the magnetic recording layer. The intermediate layer comprises a non-magnetic alloy comprising Co and Cr as its main components and an oxide such as Al, Cr, Hf. Mg, Nb, Si, Ta, Ti and Zr. Further, the average content of the oxygen element in the intermediate layer is in the range from 6 at % to 20 at %. | 08-06-2009 |
20150017480 | PERPENDICULAR MAGNETIC RECORDING MEDIUM - A magnetic recording medium includes an amorphous buffer layer, a hybrid layer including a barrier layer, and a texture control layer. The magnetic recording medium also includes a heat sink layer, an under layer, and a perpendicular recording layer. | 01-15-2015 |
Ikuko Takekuma, Yokohama JP
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20120214021 | MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING APPARATUS - There is provided a magnetic recording medium including an MgO underlayer that can be formed by a mass production process and has a thickness of 3 nm or less as well as including a magnetic recording layer made of an L1 | 08-23-2012 |
20120225325 | MAGNETIC RECORDING MEDIUM - Surface flatness of magnetic recording medium to which a magnetic recording layer made of L1 | 09-06-2012 |
Ikuko Takekuma, Yokohama-Shi JP
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20140334039 | PERPENDICULAR MAGNETIC RECORDING MEDIA HAVING NOVEL SEED LAYER - A magnetic medium for perpendicular magnetic data recording, having improved magnetic properties through use of a novel seed layer. The magnetic medium includes a substrate having a seed layer, a magnetic under-layer and a magnetic recording layer formed there-over. The seed layer includes an element selected from a first group of Cr, Co, Fe and Ni, and at least one element that is selected from the other elements of the first group or from a second group consisting of W, Mo and Ru. A buffer layer may be included between the substrate and the seed layer. | 11-13-2014 |
20140355156 | PERPENDICULAR MAGNETIC RECORDING MEDIA HAVING NOVEL MAGNETIC UNDER-LAYER STRUCTURE - A magnetic medium for perpendicular magnetic data recording having improved corrosion characteristics and reduced surface roughness. The magnetic medium includes an under-layer and a perpendicular magnetic recording layer formed over the under-layer. The under-layer can be formed of MgO and has an oxygen concentration that is greater at the perpendicular magnetic recording layer than it is away from the perpendicular magnetic recording layer. | 12-04-2014 |
Noritoshi Takekuma, Ishikawa JP
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20110118083 | MOTOR GRADER - A motor grader includes an engine, a torque converter, a drive wheel, an engine revolution detector, and a control unit. The torque converter, including a lock-up clutch, transmits driving force from the engine. The drive wheel is rotationally driven by the driving force from the engine. The engine revolution detector detects engine revolution. When the lock-up clutch is engaged, the control unit is configured to: maintain the engaged state of the lock-up clutch when the engine revolution is greater than a predetermined lock-up release revolution lower than a low idle revolution; and switch the lock-up clutch into a disengaged state when the engine revolution is less than or equal to the predetermined lock-up release revolution. | 05-19-2011 |
Toshitsugu Takekuma, Ebina-Shi JP
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20090015289 | SIGNAL TRANSMITTING DEVICE SUITED TO FAST SIGNAL TRANSMISSION - A signal transmitting circuit includes a circuit block having a driving circuit and an intra-block transmission line for transmitting a signal from the driving circuit, a circuit block having a receiving circuit and an intra-block transmission line for transmitting the signal to said receiving circuit, and a main interblock transmission line for propagating a signal between the driving and receiving circuit blocks. The inter-block transmission line is terminated by a resistor having substantially the same impedance as the interblock transmission line. The intra-block transmission lines are provided with a resistance element having a resistance substantially equal to a value derived by subtracting half of an impedance of the inter-block transmission line from an impedance of the intra-block transmission line, to lower signal amplitude and suppress reflections of a signal at branch points along the main interblock transmission line, thereby enabling a high-speed signal transfer. | 01-15-2009 |
20100289522 | SIGNAL TRANSMITTING DEVICE SUITED TO FAST SIGNAL TRANSMISSION - A signal transmitting circuit includes a circuit block having a driving circuit and an intra-block transmission line for transmitting a signal from the driving circuit, a circuit block having a receiving circuit and an intra-block transmission line for transmitting the signal to said receiving circuit, and a main interblock transmission line for propagating a signal between the driving and receiving circuit blocks. The inter-block transmission line is terminated by a resistor having substantially the same impedance as the interblock transmission line. The intra-block transmission lines are provided with a resistance element having a resistance substantially equal to a value derived by subtracting half of an impedance of the inter-block transmission line from an impedance of the intra-block transmission line, to lower signal amplitude and suppress reflections of a signal at branch points along the main interblock transmission line, thereby enabling a high-speed signal transfer. | 11-18-2010 |