Apparatus and method for performing track search
AssigneeSony Corporation
InventorTakahiro Komazaki
Life of this patent
Estimating the term…
Abstract
Apparatus for providing fine search in a sled movement mechanism employing a stepping motor by controlling the speed with which the head jumps in succession to next neighboring tracts on a disc and by causing pickup movement accurately for a distance corresponding to the distance of movement of the objective lens to realize the fine search in the sled movement mechanism employing the stepping motor. Also, the distance of head movement in the radial direction of the disc can be prescribed and, upon interruption of the head jumping operation, the head can be subsequently transported a distance corresponding to the target number of track jumps.
Claims9
An apparatus for performing a track search operation when reproducing information from a disc, the apparatus comprising:
- a head device movably supported for movement at least along a radial direction of the disc;
- a pickup movably supported on the head device for reproducing information from the disc;
- a stepping motor for moving the head device in the radial direction of the disc toward a target track to be searched;
- traverse pulse generating means coupled to the pickup for detecting a crossing of a track by the head device and for generating a plurality of traverse pulses;
- speed detecting means for detecting an interval between the traverse pulses generated by the traverse pulse generating means;
- and
- control means for generating a drive kick pulse to be supplied to the stepping motor, the control means including traverse signal generating means for generating a traverse signal indicative of a movement of the pickup along the radial direction of the disc and traverse counting means for counting edges of the traverse signal, wherein
- a speed of the head device is kept constant during the track search;
- the stepping motor is rotated one step when a number of edges of the traverse signal corresponding to one step of the stepping motor is detected;
- and
- the stepping motor is rotated by micro-step driving.
A method for performing a track search operation when reproducing information from a disc using a head supported for movement at least along a radial direction of the disc, comprising the steps of:
- driving the head at a constant speed using a stepping motor over a predetermined distance along the radial direction of the disc;
- detecting the distance over which the head has been moved along the radial direction of the disc to control the head movement in the driving step in meeting with the distance;
- movably supporting a pickup on the head;
- detecting a crossing of a track on the disc by the head using a traverse pulse generating means coupled to the pickup that outputs traverse pulses;
- detecting an interval between the traverse pulses generated by the traverse pulse generating means using a speed detecting means;
- generating a traverse signal;
- counting edges of the traverse signal;
- and
- generating tracking drive kick pulses based upon the detected interval, wherein
- the stepping motor is rotated one step when a number of edges of the traverse signal corresponding to one step of the stepping motor is detected;
- and
- the stepping motor is rotated by micro-step driving.
An apparatus for performing a track search operation when recording information from a disc, the apparatus comprising:
- supporting means for movably supporting a head device for movement at least along a radial direction of the disc;
- moving means for moving the head device along the radial direction of the disc at a constant speed toward a target track to be searched;
- traverse pulse generating means coupled to the pickup for detecting a crossing of a track by the head device and for generating a plurality of traverse pulses;
- speed detecting means for detecting an interval between the traverse pulses generated by the traverse pulse generating means;
- and
- controlling means for controlling a rotation angle of the moving means according to a number of tracks on the disc traversed by the pickup for moving the head device toward the target track, the controlling means including traverse signal generating means for generating a traverse signal and traverse counting means for counting edges of the traverse signal;
- wherein
- the head device includes a pickup movably supported on the head device for reproducing information from the disc
- the moving means includes a stepping motor that is rotated by micro-step driving;
- and
- the stepping motor is rotated one step when a number of edges of the traverse signal corresponding to one step of the stepping motor is detected.
Dependencies are inferred from the claim text.