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US3634616A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for correcting angular errors in color video signals with modulators

Assignee: Bell and Howell Co
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Filing: 1969-10-31
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Granted: 1972-01-11
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Expires: 1989-10-31
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Abstract

Abstract Apparatus for correcting effects of angular errors in a color video signal, wherein a first reference signal is modulated by at least a first portion of the spectrum of the video signal, and a second reference signal is modulated by at least a second portion of the spectrum of the video signal, wherein the second reference signal displays relative to said first reference signal an angular difference reflecting said angular errors, and wherein a composite modulated signal is produced in response to said modulated first and second portions, which composite modulated signal includes sideband components representing chrominance information of said color video signal and being disposed about a frequency which differs from a video picture carrier frequency by a stable frequency difference.

Inventors

  • 👤 Bert H Dann

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 20:47
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/79; H04N9/87; H04N9/898; H04N9/44

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 153 words
In apparatus for correcting effects of angular errors in a color video signal, in combination: first means for providing a first reference signal and a second reference signal displaying relative to said first reference signal an angular difference reflecting said angular error; second means for providing a first modulated signal by modulating said first reference signal with at least a first predetermined portion of the spectrum of said video signal; third means for providing a second modulated signal by modulating said second reference signal with at least a seconD predetermined portion of the spectrum of said video signal; and fourth means connected to said second and third means for producing in response to said first and second modulated signals a composite modulated signal in which sideband components representing chrominance information of said color video signal are disposed about a frequency which differs from a video picture carrier frequency by a stable frequency difference.
Claim 2
Dependent Claim 153 words
In apparatus for correcting effects of angular errors in a color video signal, in combination: first means for providing a first reference signal and a second reference signal displaying relative to said first reference signal an angular difference reflecting said angular error; second means for providing a first modulated signal by modulating said first reference signal with at least a first predetermined portion of the spectrum of said video signal; third means for providing a second modulated signal by modulating said second reference signal with at least a seconD predetermined portion of the spectrum of said video signal; and fourth means connected to said second and third means for producing in response to said first and second modulated signals a composite modulated signal in which sideband components representing chrominance information of said color video signal are disposed about a frequency which differs from a video picture carrier frequency by a stable frequency difference.
Claim 3
Dependent Claim 68 words
Apparatus as claimed in claim 1, wherein said first means for providing said reference signals include: means for providing a pilot signal varying in response to said angular errors; means for providing a substantially stable signal; and means for providing said second reference signal relative to the first reference signal with an angular difference corresponding to the angular difference between said substantially stable signal and said pilot signal.
Claim 4
Dependent Claim 94 words
Apparatus as claimed in claim 1, wherein said first means for providing said reference signals include: means for providing a signal having a time-varying frequency fx representing an angle modulation by said angular errors of a signal oscillating at a standard color subcarrier frequency fc; means for providing a substantially stable signal oscillating at said standard color subcarrier frequency fc; and means for providing said second reference signal relative to the first reference signal with an angular difference of (fc-fx), wherein fc is said standard color subcarrier frequency, and fx is said time-varying frequency.
Claim 5
Dependent Claim 52 words
Apparatus as claimed in claim 1, wherein: a. said second means include means for providing said first modulated signal by modulating said first reference signal with said video signal; and b. said third means include means for providing said second modulated signal by modulating said second reference signal with said video signal.
Claim 6
Dependent Claim 26 words
Apparatus as claimed in claim 1, including means for providing said first predetermined portion of said spectrum predominantly with luminance information of said color video signal.
Claim 7
Dependent Claim 26 words
Apparatus as claimed in claim 1, including means for providing said second predetermined portion of said spectrum predominantly with chrominance information of said color video signal.
Claim 8
Dependent Claim 46 words
Apparatus as claimed in claim 1, including filter means for filtering luminance information from said color video signal, and means connected between said filter means and said second means for applying said luminance information to said second means as said first predetermined portion of said spectrum.
Claim 9
Dependent Claim 46 words
Apparatus as claimed in claim 1, including filter means for filtering chrominance information from said color video signal, and means connected between said filter means and said third means for applying said chrominance information to said third means as said second predetermined portion of said spectrum.
Claim 10
Dependent Claim 99 words
Apparatus as claimed in claim 1, wherein said fourth means include: a. fifth means connected to said second means for extracting from said first modulated signal a component including predominantly luminance information of said color video signal and a picture carrier for said luminance information; b. sixth means connected to said third means for extracting from said second modulated signal a component including predominantly chrominance information of said color video signal; and c. seventh means connected to said fifth and sixth means for combining said component extracted by said fifth means and said component extracted by said sixth means.
Claim 11
Dependent Claim 21 words
Apparatus as claimed in claim 9, including demodulating means connected to said seventh means for demodulating said combined components to baseband.
Claim 12
Dependent Claim 23 words
Apparatus as claimed in claim 9, including modulating means connected to said seventh means for modulating said combined components on a predetermined carrier.
Claim 13
Dependent Claim 27 words
Apparatus as claimed in claim 9, wheRein said first means include means for providing said second reference signal with a higher frequency than said first reference signal.
Claim 14
Dependent Claim 41 words
Apparatus as claimed in claim 1, wherein: a. said color video signal is a signal which has been subjected to modulation for recording purposes; and b. said fourth means include means for effecting a demodulation of said modulation for recording purposes.

References Cited (Backward Citations)

US3141926A Cited
US3347997A Cited
US3504111A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-01-10 1975-07-12 1976-01-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-01-10 1979-07-12 1980-01-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-01-10 1983-07-12 1984-01-11 $7700.00 Window Closed / Lapsed

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