Patent ID: 6175538
Filing Date: 2001-01-16
Classification: G11B

Abstract:
A method of adjusting the initial position of a pickup of a disk recording or playback device, the device comprising a pickup movable along a signal recording surface of a disk for detecting addresses on the disk, and a sensor switch for detecting the pickup as moved to an inner peripheral side of the disk, the initial position adjusting method comprising the steps of:providing within a lead-in area at an inner peripheral portion of the disk a target region in which the pickup is to be positioned initially,moving the pickup from an inner periphery of the disk toward an outer periphery thereof and causing the pickup to overrun a distance corresponding to a predetermined period of time further toward the disk outer periphery after the sensor switch detects the passage of the pickup,reading an address A on the disk on completion of the overrun, returning the pickup to the disk inner periphery and halting the pickup upon the sensor switch detecting the passage of the pickup,correcting the overrun time to a shorter period if the address A is closer to the disk outer periphery than the target region, or correcting the overrun time to a longer period if the address A is closer to the disk inner periphery than the target region, repeating the movement of the pickup toward the disk outer periphery again and storing the overrun time enabling the pickup to reach the target region,repeating shortening of the overrun time, reversing the direction of overrun when the overrun time becomes not longer than a reference time t1 and if the address A then read is closer to the disk outer periphery than the target region, moving the pickup toward the disk inner periphery, repeating shortening or lengthening of the overrun time and storing the overrun time eventually enabling the pickup to be positioned in the target region, andoutwardly moving the pickup as returned to a position closer to the disk inner periphery than the sensor switch to move the pickup from the position of detection of the pickup by the sensor switch a distance corresponding to the stored overrun time when recording or playback is to be started again.