Manufacture of concentric patterns from spiral source
AssigneeSeagate Technology LLC
InventorsChristopher J. Formato, Neil N. Deeman
Life of this patent
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Abstract
The manufacture of magnetic disks for disk drives requires formation or servo tracks in a concentric pattern on the disk. Certain types of beam apparatuses for forming patterns on disks, however, provide spiral patterns. A ramp type deflection signal therefore is used to deflect the beam so as to form one circular pattern during each rotational cycle, and thereby convert the spiral pattern to a pattern comprising a series of circles.
Claims19
A method of forming at least one circular servo pattern on a disk recording medium, comprising:
- modulating an exposure beam in accord with a pattern of servo regions to be formed on the disk;
- rotating the disk and simultaneously translating the disk, to move the disk relative to the modulated exposure beam, while applying the modulated exposure beam to a surface of the disk during a rotation of the disk;
- and
- deflecting the modulated exposure beam during the rotation of the disk so as to produce a circular track of modulated exposure on the translating disk by the beam.
An electron beam recording system for forming concentric circular servo patterns on a disk recording medium, comprising:
- an electron beam column for generating a modulated electron beam, the electron beam column including deflection plates for controlling deflection of the electron beam in response to a deflection signal;
- a turntable, for rotating the disk and simultaneously translating the disk, to move the disk relative to the electron beam, while applying the electron beam to a surface of the disk during a plurality of immediately successive rotations of the disk;
- and
- a signal generator for supplying the deflection signal to the deflection plates of the electron beam column,
- wherein the deflection signal from the signal generator produces a cyclical deflection of the modulated electron beam sufficient to cause the system to form servo patterns in concentric circles on the disk during successive rotations of the disk.
An apparatus for forming concentric circular servo patterns on a disk recording medium, comprising:
- a beam recording and turntable system, for rotating and translating the disk recording medium past a servo recording beam;
- and
- means for deflecting the servo recording beam so as to convert a spiral pattern of servo exposure by the servo recording beam into the concentric circular servo patterns.
Dependencies are inferred from the claim text.