摘要:
According to one embodiment, a perpendicular magnetic recording medium includes a soft magnetic underlayer formed above a substrate, a lower seed layer formed above the soft magnetic underlayer, at least one upper seed layer formed above the lower seed layer, an interlayer formed above the at least one upper seed layer, a perpendicular recording layer formed above the interlayer, and a protective layer formed above the perpendicular recording layer, wherein the at least one upper seed layer comprises Ni or a Ni based alloy including N, and wherein the lower seed layer includes Ni and at least one element selected from a group consisting of: W and Cr. Other embodiments are described herein regarding perpendicular magnetic recording systems and methods of producing perpendicular magnetic media.
摘要:
An information memory device using an electromagnetic-wave resonance phenomenon is provided to achieve both high density and long-period storage of stored data. Memory cells are three-dimensionally arranged in the inside of a solid-like medium which is not contacted with a surface of the medium, and the memory cell has resonance characteristics to electromagnetic waves depending on the space coordinates of the memory cell. For the medium, a material is selected so that an electromagnetic wave having the resonance frequency of the memory cell. By observing absorption spectra of the irradiated electromagnetic wave or emission spectra after the absorption, three-dimensional space coordinates of the memory cell are calculated.
摘要:
An optical disk medium in which high density recording/reproducing is possible, an information recording method and an information reproducing method using it are provided. A pit composed of a phase change material and a recording film different from it are provided on an optical disk. The phase change pit has a pattern of a single frequency. A mark having a size on the same level as the phase change pit can be formed by melting a single phase change pit while recording and controlling the optical absorbance and the temperature of the recording film at the region. A single phase change pit is molten while reproducing. Since the optical characteristics of the molten region are different from the optical characteristics of other regions, only data at the molten region can be reproduced by a super-resolution effect.
摘要:
Provided is a recording and retrieval apparatus for a multi-layer optical disk. A multi-layer optical disk in which a plurality of recording layers and a single servo layer are combined to form a set is used. A spot for the servo layer and a spot for the recording layers are turned on in a time-sharing manner. Servo signal detection areas are formed discretely in the servo layer. The servo signal detection areas and data recording areas are provided so as not to overlap each other when viewed from the spot incident side. Thus, separation of data from each of the layers can be done by even a single photodetector without interference.
摘要:
An information recording medium includes a plurality of layers for recording or reproduction of information by irradiation, wherein each of the layers includes an emboss portion and wobble portion including wobbles of a first frequency and a second frequency that is different from the first frequency. The first frequency is constant in each of the plurality of layers, and a different signal is obtained from the wobbles of the first and second frequencies in each of the plurality of layers.
摘要:
An information recording medium including a plurality of layers for recording or reproduction of information by irradiation of light and information for identifying a tracking error signal for determining a layer number being recorded in each of the plurality of layers. A modulation of the tracking error signal is different in each of the plurality of layers.
摘要:
An information memory device using an electromagnetic-wave resonance phenomenon is provided to achieve both high density and long-period storage of stored data. Memory cells are three-dimensionally arranged in the inside of a solid-like medium which is not contacted with a surface of the medium, and the memory cell has resonance characteristics to electromagnetic waves depending on the space coordinates of the memory cell. For the medium, a material is selected so that an electromagnetic wave having the resonance frequency of the memory cell. By observing absorption spectra of the irradiated electromagnetic wave or emission spectra after the absorption, three-dimensional space coordinates of the memory cell are calculated.
摘要:
Provided is a recording and retrieval apparatus for a multi-layer optical disk. A multi-layer optical disk in which a plurality of recording layers and a single servo layer are combined to form a set is used. A spot for the servo layer and a spot for the recording layers are turned on in a time-sharing manner. Servo signal detection areas are formed discretely in the servo layer. The servo signal detection areas and data recording areas are provided so as not to overlap each other when viewed from the spot incident side. Thus, separation of data from each of the layers can be done by even a single photodetector without interference.
摘要:
Multicolor characters or pictures are written in an optical disk in a visible manner. The optical disk comprises a figure writing layer for writing a visible figure in addition to a data recording layer for recording data. Recording of user data in the data recording layer and the writing of a visible figure in the figure writing layer are performed using the same optical disk drive. In one example, the figure writing layer comprises phase change layers that are formed via protection layers in a region sandwiched between a pair of reflective layers. By writing figure data separated into individual basic colors in the phase change layers individually, a multicolor figure can be made visible.
摘要:
When external and internal environmental variation factors (characteristics of medium, variation in voltage, deterioration of medium and the like) occur, a reproduced signal is varied. In a learning system for reproduction of a voltage layer selection type multi-layer optical disk which making recording or reproducing by irradiation of energy, a level and/or pattern of an application voltage is adjusted in accordance with a reproduced signal at a predetermined position. Even if the reproduced signal, from the reflectivity down, is varied due to the external and internal environmental variation factors (characteristics of medium, variation in voltage, deterioration of medium and the like), the reproduced signal with the high quality can be obtained from the voltage layer selection type medium.