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Color television recording system employing frequency modulation and pulse width modulation

Assignee: US Philips Corp
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Filing: 1975-12-19
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Granted: 1977-08-30
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Expires: 1995-12-19
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Abstract

Abstract A color television system for transmitting a color television signal, specifically for recording on and subsequently reproducing from a record carrier. The color television signal to be transmitted contains a first carrier which is frequency-modulated with the luminance information and a second carrier which is modulated with the chrominance information, whose frequency lies between zero and the first-order lower side band of the modulated first carrier which corresponds to the highest modulation frequency. Said second carrier does not have a fixed frequency, but is locked to the instantaneous frequency of the modulated first carrier by a constant integral ratio. Depending on the characteristics of the transmission medium and the signal processing equipment said ratio is preferably two or three.

Inventors

  • 👤 Leonardus Adrianus Johannes Verhoeven
  • 👤 Maarten Rutger DE Haan
  • 👤 Peter Johannes Michiel Janssen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 19:32
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/79; H04N9/80; H04N9/86

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 97 words
A record carrier on which a color television signal having luminance and chrominance information is recorded with a low frequency chrominance signal having alternately from line to line two different single color components and a first carrier frequency modulated by the luminance information, said frequency modulated carrier being pulse-width modulated by the chrominance signal, said carrier comprising a pattern of blocks alternating with areas disposed along a track direction on said carrier, the blocks having a constant length in the track direction and representing the rising and falling edges of the frequency and pulse-width modulated first carrier.
Claim 2
Dependent Claim 97 words
A record carrier on which a color television signal having luminance and chrominance information is recorded with a low frequency chrominance signal having alternately from line to line two different single color components and a first carrier frequency modulated by the luminance information, said frequency modulated carrier being pulse-width modulated by the chrominance signal, said carrier comprising a pattern of blocks alternating with areas disposed along a track direction on said carrier, the blocks having a constant length in the track direction and representing the rising and falling edges of the frequency and pulse-width modulated first carrier.

References Cited (Backward Citations)

US3535433A Cited
US3852520A Cited
US3902010A Cited
US3778794A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-08-29 1981-02-28 1981-08-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-08-29 1985-02-28 1985-08-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-08-29 1989-02-28 1989-08-30 $7700.00 Window Closed / Lapsed

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