Scanning method and apparatus for performing track jump operations in disk player

Claim 2

In a disk player comprising a slider for carrying a pickup movably in the radial direction of a recorded disk, said pickup having a tracking actuator for adjusting a relative position of an information detecting point in a direction substantially perpendicular to a recorded track on said recorded disk, tracking error signal generating means for generating a tracking error signal corresponding to an amount of deviation of said information detecting point from said recorded track, a tracking servo loop for driving said tracking actuator so as to make said tracking error signal a minimum, and signal processing means for reproducing a readout signal obtained from said pickup when said tracking servo loop is closed, a scanning method comprising the steps of: opening said tracking servo loop in response to a scanning command; driving said tracking actuator to perform a jump operation until a number of tracks detected by a track counter for detecting a number of tracks jumped by said information detecting point reaches a designated value; and, if said scanning command continues at a point of time after a lapse of predetermined period from completion of said jump operation, performing said jump operation again.

Claim 3

The scanning method for a disk player of claim 1, wherein said designated value is determined in such a manner that a picture scanning speed for said jump operation is constant and independent of a radial position of said information detecting point to said disk.

Claim 4

The scanning method for a disk player of claim 2, wherein, for a constant linear velocity disk, said designated value is equal to N-(T-T j )/2T v for a jump operation in a forward direction and N+(T-T j )/2T v for a jump operation in a reverse direction, where T is a period of actuation of the jump operation, T j is a period of time for jumping one track, T v is a field period of recorded picture information, and N is equal to N o R o /R, where N o is a number of tracks jumped over per jump operation at an innermost circumference of said disk, R o is an innermost radius of information recorded on said disk, and R is a radius of the present position of said information detecting point.

Claim 5

The scanning method for a disk player of claim 2, wherein, for a constant angular velocity disk, said designated value is a constant value.

Claim 6

The scanning method for a disk player of claim 1, further comprising the steps of: providing a speed error signal indicative of an amount of deviation of a speed of said pickup from a predetermined value during said jump operation; supplying said speed error signal as a control signal to a tracking actuator driving circuit for driving said tracking actuator; integrating said speed error signal; and supplying said speed error signal as a control signal to a slider motor driving circuit for driving said slider.

Claim 7

A disk player comprising: a pickup and a slider for carrying said pickup movably in the radial direction of a recorded disk, said pickup comprising a tracking actuator for adjusting a relative position of an information detecting point in a direction substantially perpendicular to a recorded track on said recorded disk; tracking error signal generating means for generating a tracking error signal corresponding to an amount of deviation of said information detecting point from said recorded track; a tracking servo for driving said tracking actuator so as to make said tracking error signal a minimum; signal processing means for reproducing a read-out signal obtained from said pickup when said tracking servo loop is closed; means for opening said tracking servo loop in response to a scanning command; a track counter for detecting a number of tracks jumped during a jump operation; driving means for driving said tracking actuator to perform a jump operation until a number of tracks detected by said track counter reaches a designated value; detecting means for detecting the presence of said scanning command for a predetermined time period after the completion of said jump operation; and means responsive to said detecting means for causing said driving means to perform said jump operation again.

Claim 8

A disk player comprising: a pickup and a slider for carrying said pickup movably in the radial direction of a recorded disk, said pickup comprising a tracking actuator for adjusting a relative position of an information detecting point in a direction substantially perpendicular to a recorded track on said recorded disk; tracking error signal generating means for generating a tracking error signal corresponding to an amount of deviation of said information detecting point from said recorded track; a tracking servo for driving said tracking actuator so as to make said tracking error signal a minimum; signal processing means for reproducing a read-out signal obtained from said pickup when said tracking servo loop is closed; means for opening said tracking servo loop in response to a scanning command; a track counter for detecting a number of tracks jumped during a jump operation; driving means for driving said tracking actuator to perform a jump operation until a number of tracks detected by said track counter reaches a designated value; detecting means for detecting the presence of said scanning command for a predetermined time period after the completion of said jump operation; and means responsive to said detecting means for causing said driving means to perform said jump operation again.

Claim 9

The disk player of claim 6, wherein said designated value is determined in such a manner that a picture scanning speed for said jump operation is constant and independent of a radial position of said information detecting point to said disk.

Claim 10

The disk player of claim 7, wherein, for a constant linear velocity disk, said designated value is equal to N-(T-T j )/2T v for a jump operation in a forward direction and N+(T-T j )/2T v for a jump operation in a reverse direction, where T is a period of actuation of the jump operation, T j is a period of time for jumping one track, T v is a field period of recorded picture information, and N is equal to N o R o /R, where N o is a number of tracks jumped over per jump operation at an innermost circumference of said disk, R o is an innermost radius of information recorded on said disk, and R is a radius of the present position of said information detecting point.

Claim 11

The disk player of claim 7, wherein, for a constant angular velocity disk, said designated value is a constant value.

Claim 12

The disk player of claim 6, further comprising: a tracking actuator driving circuit for driving said tracking actuator; a slider motor driving circuit for driving said slider; means for providing a speed error signal indicative of an amount of deviation of a speed of said pickup from a predetermined value during said jump operation, said speed error signal being supplied as a control signal to said tracking actuator driving circuit; means for integrating said speed error signal, said speed error signal being supplied as a control signal to said slider motor circuit.