摘要:
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. As such, an alternating magnetic field can be applied to a magneto-optical recording medium at a predetermined angle to an in-plane direction of the recording medium to accurately enlarge a magnetic domains for reproduction.
摘要:
When recording a recorded signal consisting of “01011001110” in a magnetooptical recording medium, (1,1) corresponding to a domain of 2T is converted to (1,0,1), and (0,0) is converted to (0,1,0) in the recorded signal. In other words, the first “1” of (1,1) is converted to unit bits “1,0” and the first “0” of (0,0) is converted to unit bits “0,1”. Similarly, the first “1” of (1,1,1) corresponding to a domain of 3T is converted to unit bits “1,0”, and the second “1” is converted to unit bits “1,0”. “1” or “0” of the final unit bit is not converted but recorded as such. Consequently, a signal can be correctly reproduced by extension ally transferring domains having different domain lengths from a recording layer to a reproducing layer under the same reproducing conditions.
摘要:
A magneto-optical recording medium of magnetic domain enlarging/reproducing system including a recording layer and a reproducing layer, a gate layer selectively extracting each magnetic domain within the recording layer is formed on the recording layer, a magnetic field reinforcement layer reinforcing a leakage magnetic field reaching the reproducing layer is formed on the gate layer, and a blocking layer blocking an exchange coupling force from the magnetic field reinforcement layer to the reproducing layer is formed on the magnetic field reinforcement layer.
摘要:
A reproducing apparatus reproduces a signal recorded in a magneto-optical disk. The magneto-optical disk includes a layered structure having a recording layer, an intermediate layer and a reproducing layer. Laser light is illuminated from an optical head to the magneto-optical disk in such an intensity that no magnetic domain is transferred from the recording layer to the reproducing layer only by the laser light. In this state, alternating magnetic field is applied through a magnetic head to the magneto-optical disk, thereby concurrently causing transfer and expansion of a magnetic domain to the reproducing layer. As a result, transfer of the magnetic domain is effected with expansion.
摘要:
A reproducing apparatus reproduces a signal recorded in a magneto-optical disk. The magneto-optical disk includes a layered structure having a recording layer, an intermediate layer and a reproducing layer. Laser light is illuminated from an optical head to the magneto-optical disk in such an intensity that no magnetic domain is transferred from the recording layer to the reproducing layer only by the laser light. In this state, alternating magnetic field is applied through a magnetic head to the magneto-optical disk, thereby concurrently causing transfer and expansion of a magnetic domain to the reproducing layer. As a result, transfer of the magnetic domain is effected with expansion.
摘要:
The present invention provides smooth and adequate recording/reproducing on a recording medium employing a biodegradable material as a substrate material. The present invention relates to storing on a recording medium, information, structure, or the like indicating that a substrate is formed of a biodegradable material. When the present invention is applied to CD, CD-R, and CD-RW, identification information indicating a substrate formed of a biodegradable material is included in a free area of TOC data in a lead-in area shown in FIG. 4. An optical disc apparatus reads the identification information to identify whether or not a disc loaded into the apparatus has a substrate of a biodegradable material. When the loaded disc has a substrate of a biodegradable material, the optical disc apparatus: measures a temperature inside a drive; stops a recording/reproducing operation on the disc when the temperature approaches a glass transition temperature of a substrate material; and ejects the disc to outside of the apparatus.
摘要:
On a dielectric layer of SiN a reproduction layer, a non-magnetic layer of SiN and a recording layer of TbFeCo are formed to provide a magneto optical recording medium. The reproduction layer is formed of a first layer corresponding to a Gd layer, a second layer formed of GdFeCo and a third layer corresponding to a Gd layer. As such, the magneto optical recording medium, with the non-magnetic layer formed in contact with the reproduction layer, can prevent the non-magnetic layer from affecting the reproduction layer and thus prevent the reproduction layer from having a degraded characteristic.
摘要:
A magneto-optical recording medium including a substrate, a reproducing layer formed on the substrate, an intermediate layer formed on the reproducing layer, a recording layer formed on the intermediate layer and a high magnetization layer formed on the recording layer. The intermediate layer is made of a non-magnetic material, and set at a prescribed thickness so that a leakage magnetic field from the recording layer to the reproducing layer is so distributed that the intensity thereof is increased from an end to the center of its domain. The high magnetization layer is made of an alloy or a multilayer film of a noble metal and a transition metal having saturation magnetization stronger than that of the recording layer under a reproducing temperature. At room temperature, the coercive force of the recording layer is larger than that of the high magnetization layer. Consequently, transfer/enlargement from the recording layer to the reproducing layer is readily caused in this magneto-optical recording medium.
摘要:
A magneto-optical recording medium which includes a reproducing layer. When a laser beam is irradiated to the magneto-optical recording medium, a magnetic domain in a recording layer is transferred, through enlargement, to a reproducing layer increased in temperature. The magneto-optical recording medium further includes a calibration area that has a calibration magnetic domain recorded in a predetermined pattern in the recording layer. In a reproducing apparatus, a laser beam of an optical head is adjusted in output depending upon a reproduced signal obtained by reproducing the calibration magnetic domain.
摘要:
A magneto-optical recording medium includes a recording layer and a reproducing layer respectively formed by magnetic layers on a substrate. A record magnetic domain is formed within the recording layer by using a magnetic head, which is transferred into a reproducing layer by irradiating a laser beam upon reproduction. The physical length in recording a unit bit is taken as a unit domain length. Where the unit domain length is 1T and “1” is recorded in 1T, “1” is recorded in a former half 1T/2 and “0” is in a latter half 1T/2 by applying one period of an alternating magnetic field to the unit domain length.