Patent US3873975A successfully refreshed from Google Patents.
US3873975A
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System and method for authenticating and interrogating a magnetic record medium
Assignee: 3M Co
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Filing: 1973-05-02
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Granted: 1975-03-25
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Expires: 1993-05-02
Abstract
Abstract A magnetic record medium including a sheet having a layer containing magnetically anisotropic particles wherein the particles are permanently physically aligned at selected locations to form a fixed information pattern, is used in an authentication system in which the medium is subjected to magnetizing fields along two transverse directions to differently magnetize the particles depending upon the physical alignment thereof with respect to the field. The different magnetizations are sensed to produce signals representative of the selected locations, which signals are compared to authenticate the medium. The medium is further used in information processing systems in which a substantially unidirectional magnetizing field differently magnetizes the differently physically aligned particles, and in which the different magnetization is sensed to produce a signal representative of the fixed information.
Inventors
- 👤 Richard L Miklos
- 👤 Jack E Blackburn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:11
CPC Classifications
G; G06; G06K; G06K19/00; G06K19/02; B; B05; B05D; B05D3/00; B05D3/20; B05D3/207; G06K7/00; G06K7/08; G07; G07F; G07F7/00; G07F7/08; G07F7/086; B05D5/00; B05D5/06; B05D5/061
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
243 words
A system for authenticating a record medium having a magnetic recording layer containing uniformly dispersed magnetizable material having magnetic anisotropy, wherein the magnetizable material within selected locations of the layer is differently physically aligned from the physical alignment of the material in the remainder of the layer, to provide a magnetically detectable permanent code pattern, which system comprises: means for applying a magnetic field along a track parallel to said physical alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the physical alignment of the material along said track; means for sensing the magnetization of said magnetized material along said parallel track to provide a signal representative of said selected locations; means for applying a magnetic field along a track transverse to said physical alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the physical alignment of the material along said transverse track; means for sensing the magnetization of said magnetized material along said transverse track to provide another signal representative of said selected locations; and means for comparing amplitudes of the signals produced by the sensing means to authenticate the record medium.
Claim 2
Independent Claim
243 words
A system for authenticating a record medium having a magnetic recording layer containing uniformly dispersed magnetizable material having magnetic anisotropy, wherein the magnetizable material within selected locations of the layer is differently physically aligned from the physical alignment of the material in the remainder of the layer, to provide a magnetically detectable permanent code pattern, which system comprises: means for applying a magnetic field along a track parallel to said physical alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the physical alignment of the material along said track; means for sensing the magnetization of said magnetized material along said parallel track to provide a signal representative of said selected locations; means for applying a magnetic field along a track transverse to said physical alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the physical alignment of the material along said transverse track; means for sensing the magnetization of said magnetized material along said transverse track to provide another signal representative of said selected locations; and means for comparing amplitudes of the signals produced by the sensing means to authenticate the record medium.
Claim 3
Dependent Claim
33 words
A system according to claim 1, wherein said means for producing magnetic fields along said parallel and transverse tracks comprise means for providing identical alternating magnetic fields along both of the respective tracks.
Claim 4
Dependent Claim
138 words
A system according to claim 1, for authenticating a record medium in which said selected locations are positioned at intersections of predetermined parallel rows and parallel columns and said columns are parallel to said direction of material alignment in the selected locations, wherein in the system, said means for producing a magnetic field along a said parallel track and said means for sensing said magnetized materials along said parallel track are adapted for producing said fields and for sensing said magnetization respectively along a plurality of tracks corresponding to said columns, and wherein said means for producing a magnetic field along a said transverse track and said means for sensing said magnetized materials along said transverse track are adapted for producing sAid fields and for sensing said magnetization respectively along a plurality of tracks corresponding to said rows.
Claim 5
Dependent Claim
94 words
A system according to claim 3, wherein the means for comparing signal amplitudes further comprises means for producing a code identication signal indicative of a code location whenever a signal derived from a said selected location by magnetizing and sensing a track in a direction parallel to the physical alignment of the material within said selected location has a first amplituide and a signal derived from the same selected location by magnetizing and sensing a track transverse to the physical alignment of the material within said same selected location has a second lower amplitude.
Claim 6
Independent Claim
247 words
A system for authenticating a record medium comprising: a record medium having a magnetic recording layer containing uniformly dispersed magnetizable material having magnetic anisotropy, wherein the magnetizable material within selected locations of the layer is differently physically aligned from the physical alignment of the material in the remainder of the layer to provide a magnetically detectable permanent code pattern; means for applying a magnetic field along a track parallel to said physical alignment of the material within said selected locations to magnetize the material within said at least one selected location and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the physical alignment of the material along said track; means for sensing the magnetization of said magnetized material along said parallel track to provide a signal representative of said selected locations; means for applying a magnetic field along a track transverse to said physical alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the physical alignment of the material along said transverse track; means for sensing the magnetization of said magnetized material along said transverse track to provide another signal representative of said selected locations; and means for comparing amplitudes of the signals produced by the sensing means to authenticate the record medium.
Claim 7
Independent Claim
247 words
A system for authenticating a record medium comprising: a record medium having a magnetic recording layer containing uniformly dispersed magnetizable material having magnetic anisotropy, wherein the magnetizable material within selected locations of the layer is differently physically aligned from the physical alignment of the material in the remainder of the layer to provide a magnetically detectable permanent code pattern; means for applying a magnetic field along a track parallel to said physical alignment of the material within said selected locations to magnetize the material within said at least one selected location and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the physical alignment of the material along said track; means for sensing the magnetization of said magnetized material along said parallel track to provide a signal representative of said selected locations; means for applying a magnetic field along a track transverse to said physical alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the physical alignment of the material along said transverse track; means for sensing the magnetization of said magnetized material along said transverse track to provide another signal representative of said selected locations; and means for comparing amplitudes of the signals produced by the sensing means to authenticate the record medium.
Claim 8
Dependent Claim
80 words
A system according to claim 5, wherein said layer within said record medium contains magnetic particles uniformly dispersed in a flexible binder, wherein the particles are physically aligned in one direction within said selected locations and are aligned perpendicular to the one direction in the remainder of the layer, and wherein the magnetization along a track transverse to said physical alignment of the material within said selected locations is parallel to the physical alignment in the remainder of the layer.
Claim 9
Dependent Claim
12 words
A system according to claim 6, wherein said particles are acicular gamma-Fe2O3.
Claim 10
Dependent Claim
34 words
A system according to claim 5, wherein said material within said selected locations is aligned in one direction and the material in the remainder of the layer is aligned perpendicular to said one direction.
Claim 11
Dependent Claim
108 words
An information processing system for interrogating a record medium, comprising: a magnetic record medium having a magnetic recording layer containing uniformly dispersed magnetizable material having magnetic anisotropy which magnetizable material at selected locations on the layer is differently aligned from the alignment of the magnetizable material in the remainder of the layer to provide a magneticallly detectable permanent fixed information pattern, means for applying a first substantially unidirectional magnetic field to differently magnetize said magnetizable material depending upon the alignment thereof, and sensor means for sensing the magnetization of the differently magnetized material upon traversing said record medium to provide a signal represeNtative of said fixed information pattern.
Claim 12
Dependent Claim
108 words
An information processing system for interrogating a record medium, comprising: a magnetic record medium having a magnetic recording layer containing uniformly dispersed magnetizable material having magnetic anisotropy which magnetizable material at selected locations on the layer is differently aligned from the alignment of the magnetizable material in the remainder of the layer to provide a magneticallly detectable permanent fixed information pattern, means for applying a first substantially unidirectional magnetic field to differently magnetize said magnetizable material depending upon the alignment thereof, and sensor means for sensing the magnetization of the differently magnetized material upon traversing said record medium to provide a signal represeNtative of said fixed information pattern.
Claim 13
Dependent Claim
40 words
A system according to claim 9, further comprising means for demagnetizing said differently magnetized material in inhibit magnetic detection of the selected locations unless and until a said substantially unidirectional magnetic field is again applied to said magnetic recording layer.
Claim 14
Dependent Claim
22 words
A system according to claim 9, further comprising second sensor means for reproducing information recorded onto the record medium for data processing.
Claim 15
Dependent Claim
81 words
A system according to claim 9, further comprising means for applying a second substantially unidirectional magnetic field having its major field component transverse to the direction of said first substantially unidirectional magnetic field to differently magnetize said magnetizable particles depending upon the alignment thereof, means for sensing the magnetization of the differently magnetized particles upon traversing the record medium to provide a second signal representative of said detectable fixed information pattern, and means for comparing the amplitudes of the representative signals.
Claim 16
Independent Claim
230 words
A method for authenticating a record medium having a magnetic recording layer containing uniformly dispersed magnetizable material having magnetic anisotropy, wherein the magnetizable material within selected locations of the layer is differently aligned from the alignment of the material in the remainder of the layer, to provide a magnetically detectable permanent code pattern, which method comprises the following steps: applying a magnetic field along a track parallel to said alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the alignment of the material along said track; sensing the magnetization of said magnetized material along said parallel track to provide a signal representative of said selected locations; applying a magnetic field along a track transverse to said alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the alignment of the material along said transverse track; sensing the magnetization of said magnetized material along said transverse track to provide another signal representative of said selected locations; and comparing amplitudes of the signals produced by the sensing means to authenticate the record medium.
Claim 17
Independent Claim
230 words
A method for authenticating a record medium having a magnetic recording layer containing uniformly dispersed magnetizable material having magnetic anisotropy, wherein the magnetizable material within selected locations of the layer is differently aligned from the alignment of the material in the remainder of the layer, to provide a magnetically detectable permanent code pattern, which method comprises the following steps: applying a magnetic field along a track parallel to said alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the alignment of the material along said track; sensing the magnetization of said magnetized material along said parallel track to provide a signal representative of said selected locations; applying a magnetic field along a track transverse to said alignment of the material within said selected locations to magnetize the material within said selected locations and to differently magnetize at least a portion of the material in said remainder of the layer adjacent said selected locations, depending upon the alignment of the material along said transverse track; sensing the magnetization of said magnetized material along said transverse track to provide another signal representative of said selected locations; and comparing amplitudes of the signals produced by the sensing means to authenticate the record medium.
Claim 18
Dependent Claim
29 words
A method according to claim 13, wherein said steps of producing magnetic fields along said parallel and transverse tracks comprises providing identical alternating magnetic fields along the respective tracks.
Claim 19
Dependent Claim
128 words
A method according to claim 13 for authenticating a record medium in which selected locations are positioned at intersections of predetermined parallel rows and parallel columns, and said columns are parallel to said direction of material alignment in the selected locations, in which method, said step of producing a magnetic field along said parallel track and said step of sensing said magnetized material along said parallel track comprises producing said field and sensing said magnetization respectively along a plurality of tracks corresponding to said columns, and said step of producing a magnetic field along a said transverse track and said step of sensing said magnetized material along said transverse track comprises producing said field and sensing said magnetization respectively along a plurality of tracks corresponding to said rows.
Claim 20
Dependent Claim
91 words
A method according to claim 15, wherein the step of comparing the signal amplitudes further comprises producing a code identification signal indicative of a selected location whenever a signal derived from a said selected location by magnetizing and sensing a Track in a direction parallel to the alignment of the material within said selected location has a first amplitude, and a signal derived from the same selected location by magnetizing and sensing a track transverse to the alignment of the material within said same selected location has a second lower amplitude.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |