System for recording and/or reproducing information, magnetic write head for use in the system, magnetic tape for use in the system, cassette for use in the system, and arrangement for formatting the magnetic tape
AssigneeKoninklijke Philips Electronics N.V.
InventorStephen Rodney Cumpson
Life of this patent
Estimating the term…
Abstract
A system for recording and/or reproducing information, including a magnetic tape formatted by means of a magnetic write head which is movable in a longitudinal direction (x) and which forms “buried” servo tracks of different widths. The amplitude of the servo read signals as a function of the position of the magnetic read/write head of the apparatus with respect to the “buried” servo tracks of the magnetic tape in the width direction (y) is substantially the same for the all the read/write units of the read/write head in spite of the width differences.
Claims12
A system for recording and/or reproducing information, comprising a magnetic tape (10) formatted with the aid of a magnetic write head which is movable in a longitudinal direction (x) with respect to said magnetic tape and including an apparatus having a magnetic read/write head having magnetic read/write units for writing data tracks into a magnetic tape which is movable in a longitudinal direction (x) with respect thereto, which read/write head is movable in a width direction (y) with respect to the longitudinal direction (x) of the magnetic tape by means of an actuator, the magnetic tape being previously provided with a pattern of buried servo tracks (STn) by means of the write head, which buried servo tracks extend in the longitudinal direction (x) and which alternately contain a different servo signal, at least one group of juxtaposed servo tracks of a width (w1) being provided and at least one servo track of greater width being provided, which apparatus further includes control means for controlling the actuator by means of a control signal, which control means receive servo read signals which originate from servo signals embedded in adjacent servo tracks and read by the read/write units of said magnetic read/write head and process said servo read signals in a processing unit so as to form said control signal for the actuator, characterized in that
- the amplitude of the servo read signal as a function of the position of the magnetic read/write head of the apparatus with respect to the magnetic tape in the width direction (y) is substantially equal for all the read/write units of the read/write head.
A system as claimed in any one of the preceding Claims, characterized in that
- the buried servo signals in the servo tracks alternately consist of a servo signal (Sa) and a servo signal (Sb),
- the servo signals (Sa and Sb) substantially consist of sinusoidal signals of the same frequency but of opposite phase, and
- the amplitudes of the servo signals (Sa and Sb) are substantially equal to one another.
A magnetic tape provided with a pattern of buried servo tracks, comprising
- buried servo tracks of a first type containing a first servo signal (Sa), and
- buried servo tracks of a second type containing a second servo signal (Sb), which servo tracks extend substantially in a longitudinal direction (x) and which track pattern, in a transverse direction (y) perpendicular to the longitudinal direction (x), alternately comprises a servo track of the first type and a servo track of the second type, at least one group of servo tracks having a width w1 and at least one servo track of a greater width being present, which magnetic tape is intended for cooperation with a magnetic read/write head of a given type which is movable by an actuator in a width direction (y) with respect to the longitudinal direction (x) of the magnetic tape, characterized in that
- during cooperation with said magnetic read/write head of the given type the amplitude of the servo read signals as a function of the position in the width direction (y) of the magnetic read/write head with respect to the magnetic tape is substantially the same for all the read/write units of the read/write head.
An arrangement for formatting a magnetic tape, including a magnetic write head and means for scanning a magnetic tape by means of the magnetic write head, in which:
- the write head has a head face having a longitudinal direction (x) which corresponds to the longitudinal direction of movement of a magnetic tape with respect to the write head, and a width direction (y) which is perpendicular to the longitudinal direction and extends parallel to a generatrix of the head face,
- a structure of integrated write units has been provided in the write head,
- the write units are juxtaposed and extend in the width direction (y), and
- each of the write units has at least one write gap which terminates in the head face and has a dimension in the width direction, which dimension corresponds to the width of the corresponding servo track, and
- at least one group of juxtaposed write units of a width w1 being provided and at least one write unit of greater width being provided, characterized in that
- each write unit of greater width consists of a set of write sub-units with a spacing between each pair of adjacent write sub-units, each write sub-unit having the width of a signal-carrying sub-track and the spacing having the width of an empty sub-track.
Dependencies are inferred from the claim text.