摘要:
A position sensor detects a position of an objective lens for irradiating light onto an optical disk. An output adjustment of the position sensor is used for correcting characteristics change due the change with the passage of time. The position of an objective lens and the output of a position sensor are measured at a reference time, the ratio at the neutral point is determined in advance, and when the device is used, the position of the objective lens and the output of the position sensor are measured. The output level at the neutral point during using the device is calculated from the measurement result and the ratio at the neutral point.
摘要:
A position sensor detects a position of an objective lens for irradiating light onto an optical disk. An output adjustment of the position sensor is used for correcting characteristics change due the change with the passage of time. The position of an objective lens and the output of a position sensor are measured at a reference time, the ratio at the neutral point is determined in advance, and when the device is used, the position of the objective lens and the output of the position sensor are measured. The output level at the neutral point during using the device is calculated from the measurement result and the ratio at the neutral point.
摘要:
A magnetic disk device performs test write on a test cylinder to check the state of each head before system information is stored in disks. The magnetic disk device then determines the state of each head based on the test write results stored in a test-write-result table. When a head is defective, the magnetic disk device notifies a host of the possibility of the occurrence of a timeout as a fault prediction.
摘要:
A magnetic disk device performs test write to check the state of each of heads before system information is stored in a disk and, based on the result of the test write, stores the system information sequentially with the heads from one in good state. After a predetermined time has elapsed, the magnetic disk device suspends the process of storing the system information.
摘要:
An information storage apparatus includes a mark reading section for reading a mark written on an information storage medium. A recording state changing section is provided for changing a recording state in an adjacent region situated next to a region from which the mark reading section fails to read a mark, so as to reduce cross talk caused by the adjacent region. The mark reading section reads the mark in the failed region again after the recording state changing section changes the recording state in the adjacent region.
摘要:
A storage apparatus uses a light beam to reproduce information from a recording medium having an information region with a recording format which includes a header including position information and a recording field including a data field for recording data. The storage apparatus is provided with a light source for emitting the light beam, and a control section for controlling a power L2 of the light beam in a vicinity of a start of the recording field to become higher than a power L3 at the data field of the recording field.
摘要:
A magnetic disk device performs test write before storing system information to check the state of each head. The magnetic disk device then stores test write results in a test-write-result table of a RAM. The magnetic disk device then determines whether the number of defective heads is equal to or greater than a predetermined number. When the number of defective heads is equal to or greater than the predetermined number, the magnetic disk device suspends the process of storing the system information. When the number of defective heads is less than the predetermined number, the magnetic disk device refers to the test write results stored in the test-write-result table and performs write only with a head determined as normal.
摘要:
A defective sector is processed so that a mark can be normally read in a sector adjacent to a defective sector. A recording state of a sector determined as a defective sector (step S102: Yes) is changed to another recording state in which a level of cross talk is low (step S103).