Data storage device, apparatus and method for using same

A card and card writer/reader system comprising:

• a magnetically encodeable card having a body having upper and lower surfaces and side and end edges, said body including on at least one of said upper and lower surfaces a data storage device adapted to interact with a data processing station when said card and said data processing station are moved relative to each other, said data storage device including at least one thin film layer of high density, high coercivity magnetic material having a predetermined magnetic field orientation for storing data;
• a diamond-like hardness, abradeable protective coating formed on said thin film magnetic material layer and being selected to have a thickness between a maximum thickness which would materially attenuate magnetic signals passing between said magnetic material layer and a transducer and a minimum thickness enabling said protective coating to be abraded by usage in an ambient natural atmosphere operating environment for removing therefrom a known quantity of the protective coating;
• a first transducer for reading said magnetically encoded signals from said data storage device during relative movement of said card relative to the data processing station to enable data flow between said data storage device and said transducer;
• and
• a second transducer for writing magnetically encoding signals in said data storage device as magnetically encoded signals during relative movement of said card relative to the data processing station to enable data flow between said data storage device and said transducer.

A method for reading a card with a card reader comprising the steps of:

• forming on a substrate of a card a data storage section adapted to interact with a data processing station when said card and said data processing station are moved relative to each other to at least one of write encoding signals in said data storage section as encoded signals and read encoded signals from said data storage section;
• forming a relatively hard, abradeable protective coating on said data storage section wherein said protective coating has a thickness between a maximum thickness which would materially attenuate encoding and encoded signals passing between said data storage section and a transducer and a minimum thickness enabling said protective coating to be abraded by usage in an ambient natural atmosphere operating environment for removing therefrom a known quantity of the protective coating;
• and
• moving said card and data processing station relative to each other to interface said data storage section relative to a transducer to enable data flow therebetween.

A method for reading a card with a card reader comprising the steps of

• forming on a substrate of a card a data storage section including a thin film of magnetic material having a predetermined magnetic orientation for storing data in a predetermined axis;
• forming on said data storage section a bendable, diamond like hardness protective coating having a thickness which allows passage of magnetic signals in an ambient natural atmospheric operating environment through said protective layer and said thin film layer, said protective layer being formed of a material which resists at least one of chemical, magnetic and mechanical degradation of the data storage device;
• and
• moving said card and data processing station relative to each other to interface said data storage section relative to a transducer to enable data flow therebetween.

A magnetic signal processing apparatus comprising:

• a magnetic recording medium having a high density magnetically coercive material for storing magnetic signals with the coercive material axes of magnetization oriented in a predetermined direction:
• a non-magnetic material disposed on said high density magnetically coercive material for defining a exchange break layer;
• a bendable, relative hard, protective coating including a magnetically permeable, magnetically saturable material disposed on said exchange break layer and being responsive through said exchange break layer to the coercive material axes of magnetization to produce a magnetic image field in a direction opposite to said predetermined direction, said protective coating being selected to have a thickness between a maximum thickness which would materially attenuate magnetic signals passing between said magnetic material layer and a transducer and a minimum thickness enabling said protective coating to be abraded by usage in an ambient natural atmosphere operating environment for removing therefrom a known quantity of the protective coating;
• a magnetic transducer positioned relative to a surface of said recording medium for transferring signals with respect to the recording medium;
• a drive member operatively coupled to at least one of said transducer and said recording medium to provide relative movement therebetween;
• and
• a magnetic control device having a bias field adapted to increase through said protective coating the reluctance of said magnetic saturable, magnetically permeable material to enable a magnetic signal to pass between said high density magnetically coercive material through said exchange break layer and said protective coating to said magnetic transducer.

In a method of processing magnetic signals using a magnetic recording medium having a high density magnetically coercive material for storing magnetic signals with the coercive material axes of magnetization oriented in a predetermined direction comprising the steps of:

• providing a layer of a non-magnetic material disposed on said high density magnetically coercive material for defining a exchange break layer;
• providing a protective coating including a magnetically permeable, magnetically saturable material which is disposed on said exchange break layer and responsive through said exchange break layer to the coercive material axes of magnetization to produce a magnetic image field in a direction opposite to said predetermined direction, said protection coating being formed of a material which resists at least one of chemical, magnetic and mechanical degradation of the magnetic recording medium;
• and
• generating with a magnetic control device having a bias field adapted to increase through said protective coating and said exchange break layer the reluctance of said magnetic saturable, magnetically permeable material to enable the magnetic signal to pass between said high density magnetically coercive material through said exchange break layer and said protective coating to a magnetic transducer.

A system comprising:

• a magnetic recording medium having a high density magnetically coercive material for storing magnetic signals with the coercive material axes of magnetization oriented in a predetermined direction;
• a non-magnetic material disposed on said high density magnetically coercive material for defining a exchange break layer;
• a relatively hard, abradeable protective coating formed on said magnetic material layer and being selected to have a thickness between a maximum thickness which would materially attenuate magnetic signals passing between said a high density magnetically coercive material and a transducer and a minimum thickness enabling said protective coating to be abraded by usage in an ambient natural atmosphere operating environment for removing therefrom a known quantity of the protective coating;
• a magnetic transducer positioned relative to a surface of said recording medium for transferring signals with respect to the recording medium;
• a drive member operatively coupled to at least one of said transducer and said recording medium to provide relative movement therebetween;
• a magnetic control device having a bias field adapted to increase through said protective coating the reluctance of said magnetic saturable, magnetically permeable material to enable the magnetic signal to pass between said high density magnetically coercive material through said exchange break layer and said protective coating to said magnetic transducer;
• and
• a programmable control device operatively connected to said magnetic control device to cause said bias field to be applied to said recording medium when a selected magnetic image is located substantially adjacent said transducer.