Patent ID: 7361456

Claim:
A method of manufacturing a master disk, comprising: a step of rotating a master disk about a center point of the master disk, the master disk being mounted on a support arm having a rotational center other than the center point of the master disk; a step of moving said support arm about the rotational center of the support arm to thereby move the center point of the master disk in a rotational orbit, the moving causing a beam applied to the master disk to trace along an arc to move to a first position; a step of reading a moving distance of the master disk; a step of calculating a radial distance of the beam from the first position to the center point of the master disk; a step of determining a difference between the moving distance and the radial distance; and a step of controlling a position of the beam depending on the determined difference to move the beam to a new position on the arc to thereby facilitate uniformity in track pitches of the master disk.