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US4180833A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus and method for reproducing video signals

Assignee: Sony Corp
•
Filing: 1978-02-15
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Granted: 1979-12-25
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Expires: 1998-02-15
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Abstract

Abstract In an apparatus for reproducing video signals which are recorded as modulations of a carrier on a record medium, such as a magnetic tape, in successive, abutting parallel record tracks, with the signals being recorded in alternating tracks with different first and second azimuth angles, first and second magnetic heads are provided for sequentially scanning the tracks in which signals are recorded with the first and second azimuth angles, respectively, and the first and second magnetic heads having azimuth angles corresponding to the first and second azimuth angles of the respective tracks to be scanned thereby. Each of the magnetic heads is dimensioned and guided in the direction transverse to the direction along the respective track being scanned so as to overlap an adjacent track by a distance ΔW=nλ/tan θ(n=1,2, . . .), in which λ is the wavelength of the carrier as modulated by synchronizing signal portions of the video signals recorded in such adjacent track, and θ is the difference between the first and second azimuth angles of the heads. In this manner, cross-talk from the adjacent track is substantially attenuated.

Inventors

  • 👤 Masaru Nishikawa
  • 👤 Toshihiko Numakura
  • 👤 Jun Hirai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 04:44
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/76; H04N5/78; H04N5/782; H04N5/783; G; G11; G11B; G11B23/00; G11B23/0007; G11B5/00; G11B5/48; G11B5/488; G11B5/4893; G11B5/52; G11B5/53; G11B5/531; G11B5/534; H04N5/7824; H04N5/7826; H04N5/78263

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 257 words
An apparatus for reproducing video signals recorded on a record medium in successive parallel record tracks which abut along their longitudinal edges and in which the recorded video signals include information and synchronizing signal portion modulating a carrier, a first set of said record tracks being comprised of every other one of the latter and having video signals recorded therein at a first azimuth angle which is different from a second azimuth angle with which video signals are recorded in the remaining tracks constituting a second set of record tracks, and said synchronizing signal portions of the video signals, as recorded in adjacent tracks, are out of alignment with each other; said apparatus comprising: first and second magnetic heads for sequentially scanning tracks of said first and second sets of tracks, respectively, said first and second magnetic heads having azimuth angles corresponding to said first and second azimuth angles of the respective tracks to be scanned thereby, and each of said heads being dimensioned and guided in the direction transverse to that along the track being scanned so as to span the full width of the track being scanned and to overlap an adjacent track by a distance ΔW=nλ/tanθ (n=1, 2, . . .), wherein λ is the wavelength of the carrier as modulated by said synchronizing signal portions of the video signals in said adjacent track and θ is the difference between said first and second azimuth angles of said heads, so as to substantially attenuate the most troublesome of the cross-talk from said adjacent track.
Claim 2
Independent Claim 257 words
An apparatus for reproducing video signals recorded on a record medium in successive parallel record tracks which abut along their longitudinal edges and in which the recorded video signals include information and synchronizing signal portion modulating a carrier, a first set of said record tracks being comprised of every other one of the latter and having video signals recorded therein at a first azimuth angle which is different from a second azimuth angle with which video signals are recorded in the remaining tracks constituting a second set of record tracks, and said synchronizing signal portions of the video signals, as recorded in adjacent tracks, are out of alignment with each other; said apparatus comprising: first and second magnetic heads for sequentially scanning tracks of said first and second sets of tracks, respectively, said first and second magnetic heads having azimuth angles corresponding to said first and second azimuth angles of the respective tracks to be scanned thereby, and each of said heads being dimensioned and guided in the direction transverse to that along the track being scanned so as to span the full width of the track being scanned and to overlap an adjacent track by a distance ΔW=nλ/tanθ (n=1, 2, . . .), wherein λ is the wavelength of the carrier as modulated by said synchronizing signal portions of the video signals in said adjacent track and θ is the difference between said first and second azimuth angles of said heads, so as to substantially attenuate the most troublesome of the cross-talk from said adjacent track.
Claim 3
Dependent Claim 14 words
An apparatus according to claim 1; in which said video signals are frequency modulated.
Claim 4
Dependent Claim 37 words
An apparatus according to claim 1; in which each of said magnetic heads is guided so that one side of the head moves along a longitudinal edge of the respective one of said record tracks being scanned.
Claim 5
Dependent Claim 44 words
An apparatus according to claim 1; further comprising means for shifting the position of said heads in the direction transverse relative to the longitudinal direction of the respective tracks to be scanned so as to overlap the respective adjacent tracks by said distance ΔW.
Claim 6
Dependent Claim 64 words
An apparatus according to claim 1; in which said heads are rotary, and in which said means for shifting the position of said heads includes servo circuit means for controlling the rotating phase of said heads in response to a phase difference between pulses corresponding to the rotary position of said heads and pulses corresponding to track identifying pulses reproduced from said record medium.

References Cited (Backward Citations)

US3157738A Cited
US3925816A Cited
US3911483A Cited
US3939485A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-12-24 1983-06-25 1983-12-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-12-24 1987-06-25 1987-12-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-12-24 1991-06-25 1991-12-25 $7700.00 Window Closed / Lapsed

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