US3838446A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi layer magnetic recording technique
Assignee: NEC Corp
•
Filing: 1972-11-08
•
Granted: 1974-09-24
•
Expires: 1992-11-08
Abstract
Abstract According to this multi-layer recording technique, a relatively low-frequency signal track is recorded on a magnetic tape in the direction of the tape''s motion. A relatively shallow portion of the first recorded track along the surface of the magnetic tape is erased, and a plurality of second relatively high-frequency signal tracks that traverse the first track are recorded. The first track may contain audio information while the second track contains video information.
Inventors
- 👤 T Konishi
- 👤 H Otsuka
- 👤 N Manabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:15
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/76; H04N5/78; H04N5/782; H04N5/7824; H04N5/7826
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
120 words
A magnetic recording apparatus comprising: first recording means for recording at least one relatively low frequency signal on a magnetic tape so as to form at least one first recording track thereon which may extend to a substantial depth of the magnetic coating of said tape; means for erasing a shallow portion of said first recorded track along the surface on which it was recorded, said erased portion having a constant predetermined depth; and second recording means for scanning the surface on which the erasure was made to record a relatively high frequency signal within the erased portion and in a direction traversing said first recorded track so as to form a second recorded track traversing said first recorded track.
Claim 2
Dependent Claim
120 words
A magnetic recording apparatus comprising: first recording means for recording at least one relatively low frequency signal on a magnetic tape so as to form at least one first recording track thereon which may extend to a substantial depth of the magnetic coating of said tape; means for erasing a shallow portion of said first recorded track along the surface on which it was recorded, said erased portion having a constant predetermined depth; and second recording means for scanning the surface on which the erasure was made to record a relatively high frequency signal within the erased portion and in a direction traversing said first recorded track so as to form a second recorded track traversing said first recorded track.
Claim 3
Dependent Claim
31 words
The apparatus of claim 1, wherein said relatively high frequency signal is a video signal, and said second recording means comprises four heads mounted in quadrature relationship on a rotatable disc.
Claim 4
Dependent Claim
39 words
The apparatus of claim 2, wherein said first recording means comprises a plurality of magnetic recording heads for recording a plurality of speech signals in different languages with a plurality of recorded tracks assigned to each respective speech signal.
Claim 5
Independent Claim
108 words
A method of recording signals on a magnetic tape comprising: recording At least one relatively low frequency signal on said magnetic tape in the direction in which the tape is transported so as to form at least one first track thereon; erasing a shallow portion of said first track along the surface on which it was recorded, said erased portion having a constant predetermined depth; and recording a relatively high frequency signal by scanning the surface on which the erasure was made to record said second track within the erased portion and in a direction traversing said first track so as to form a second recorded track thereon.
Claim 6
Independent Claim
108 words
A method of recording signals on a magnetic tape comprising: recording At least one relatively low frequency signal on said magnetic tape in the direction in which the tape is transported so as to form at least one first track thereon; erasing a shallow portion of said first track along the surface on which it was recorded, said erased portion having a constant predetermined depth; and recording a relatively high frequency signal by scanning the surface on which the erasure was made to record said second track within the erased portion and in a direction traversing said first track so as to form a second recorded track thereon.
Claim 7
Dependent Claim
28 words
The method of claim 4, wherein said relatively high frequency signal is a video signal and is recorded by rotating four heads in quadrature relationship to each other.
Claim 8
Dependent Claim
14 words
The method of claim 5, wherein said low frequency signal is an audio signal.
Claim 9
Dependent Claim
31 words
The method of claim 5, wherein more than one low frequency signal is recorded, each signal containing a different language and each speech signal being recorded by a different mangetic head.
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) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |