Method and apparatus for determining position of optical pick-up head
AssigneeMediatek Inc.
InventorTun-Hsing Liu
Life of this patent
Estimating the term…
Abstract
The displacement of a pick-up head along the radial direction of an optical disk is detected, and the absolute position of the pick-up head is determined by the accumulation of the displacement, hence the apparatus knows which area on the optical disk the pick-up head currently stays. After obtaining control signals for a motor to drive the pick-up head to move along the radial direction, the apparatus calculates the displacement of the pick-up head during every stroke according the control signals. Afterward, the absolute position is determined by the accumulation of the displacement during all strokes.
Claims21
A method for determining the position of a pick-up head, comprising the steps of:
- designating a basic point on a radial line of an optical disk;
- obtaining the information of displacement of the pick-up head from control signals for driving the pick-up head to move, wherein the information of displacement is based on a relative position between the pick-up head and the basic point during each stroke of the pick-up head;
- and
- determining a representative position value of the pick-up head on the radial line of the optical disk according to the obtained information of displacement.
An apparatus for determining the position of a pick-up head, wherein the pick-up head is mounted on a lead screw and a motor drives the lead screw to move the pick-up head along a radial line of an optical disk, comprising:
- a position calculation unit obtaining the information of displacement of the pick-up head from control signals for driving the pick-up head to move and calculating a distance along the radial line between the position of the pick-up head and a basic point according to the information of displacement, wherein the information of displacement is based on a relative position between the pick-up head and the basic point during each stroke of the pick-up head.
An apparatus for determining the position of a pick-up head, wherein the pick-up head is mounted on a lead screw and a motor drives the lead screw to move the pick-up head along a radial line of an optical disk, comprising:
- a position calculation unit obtaining the information of displacements of the pick-up head and calculating a distance along the radial line between the position of the pick-up head and a basic point according to the information of displacement, wherein the distance is function of a pulse number applied to the motor during a stroke, a lead pitch of the lead screw, and a stepping angle of the motor.
A method for determining the position of a pick-up head, comprising the steps of:
- designating a basic point on a radial line of an optical disk;
- obtaining the information of displacement of the pick-up head relative to the basic point along the radial line of the optical disk for a pick-up head during each stroke;
- calculating a distance of each stroke based on the information of displacement, wherein the distance is a function of a pulse number applied to a motor powering the pick-up head during a stroke, a lead pitch of a lead screw driving the pick-up head, and a stepping angle of the motor;
- and
- determining the representative position value of the pick-up head on the radial line of the optical disk according to the distance.
Dependencies are inferred from the claim text.