Patent US4646169A successfully refreshed from Google Patents.
US4646169A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording device
Assignee: Sony Corp
•
Filing: 1986-03-05
•
Granted: 1987-02-24
•
Expires: 2006-03-05
Abstract
Abstract Described is a magnetic recording device in which digital data are recorded with higher density in such a manner that plural recording tracks are sequentially formed on the magnetic recording medium. In the magnetic recording device, any two adjoining tracks are formed by separate magnetic heads whose azimuth angles are equal to + theta , - theta , with the absolute value of the angle theta being selected to satisfy the relation 16 DEG </= theta </=22 DEG , in a manner so that the crosstalk level between any two neighboring tracks may be reduced without affecting the SN ratio.
Inventors
- 👤 Yoshihide Shimpuku
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:51
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/18; G11B15/46; G11B15/52; G11B5/00; G11B5/02; G11B5/09; G11B5/48; G11B5/488; G11B5/52; G11B5/53; G11B5/531; G11B5/534; G11B5/56
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
136 words
Apparatus for recording digital data on a magnetic recording medium in a plurality of successive parallel recording tracks formed in adjoining relation to respective neighboring tracks, in which upon reproduction a signal representing the digital data reproduced from one said track is subjected to crosstalk from signals reproduced from tracks adjacent thereto and is further subject to digital errors at a block error rate corresponding to a bit rate of recording of said digital data in said tracks, said apparatus comprising first and second magnetic heads for alternately recording said digital data in successive ones of said tracks and having first and second azimuth angles equal to +θ and -θ, respectively, where, in order to minimize the combined effect of said crosstalk and said block error rate, angle θ is selected to satisfy the relation 16°≦θ≦22°.
Claim 2
Dependent Claim
136 words
Apparatus for recording digital data on a magnetic recording medium in a plurality of successive parallel recording tracks formed in adjoining relation to respective neighboring tracks, in which upon reproduction a signal representing the digital data reproduced from one said track is subjected to crosstalk from signals reproduced from tracks adjacent thereto and is further subject to digital errors at a block error rate corresponding to a bit rate of recording of said digital data in said tracks, said apparatus comprising first and second magnetic heads for alternately recording said digital data in successive ones of said tracks and having first and second azimuth angles equal to +θ and -θ, respectively, where, in order to minimize the combined effect of said crosstalk and said block error rate, angle θ is selected to satisfy the relation 16°≦θ≦22°.
Claim 3
Dependent Claim
82 words
Apparatus according to claim 1, in which said first and second magnetic heads each have a head width T W , said tracks are formed on the recording medium with a track pitch T P less than said head width T W such that side edges of each track overlap opposing side edges of the respective neighboring tracks, and in which the ratio λ/T P is selected to be less than 0.2, where λ is a maximum recording wavelength of said apparatus.
Claim 4
Dependent Claim
48 words
Apparatus according to claim 2, in which said first and second magnetic heads are rotated to form said tracks inclined relative to a longitudinal direction of said recording medium, and in which said first and second azimuth angles are selected to be equal to +20° and -20°, respectively.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-02-23 | 1990-08-25 | 1991-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-23 | 1994-08-25 | 1995-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-23 | 1998-08-25 | 1999-02-24 | $7700.00 | Window Closed / Lapsed |