US5426632A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Information recording medium and method for recording information to the same
Assignee: Pioneer Video Corp
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Filing: 1994-08-11
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Granted: 1995-06-20
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Expires: 2014-08-11
Abstract
Abstract An optical information recording medium recordable of the analogue NTSC color video signal under the conditions of a high S/N ratio and a low jitter, and capable of being played by a commercially available LD player. The medium comprises: a transparent substrate on which pre-grooves are formed with a depth of 1450-2050 angstroms; an optical absorbing layer with an absorbance of 0.7-0.9 made of palladium phthalocyanine dye formed on the substrate, the absorbing layer having pits each having a changed reflectivity being duty-cycle modulated in response to a limited waveform which is formed through the steps of: adding at least one of a second FM carrier and a third pulse carrier to a first FM carrier having a first center frequency and a first frequency band, the second FM carrier having a second center frequency lower than the first center frequency and a second frequency band spaced from the first frequency band, the third pulse carrier having a pulse-repetition frequency lower than the second center frequency and a third frequency band spaced from the second frequency band, to form a frequency-division multiplex signal; and symmetrically clipping the multiplex signal to form the limited waveform; and reflecting layer formed on the optical absorbing layer.
Inventors
- 👤 Shigenori Murakami
- 👤 Toshihiko Takishita
- 👤 Kenji Suzuki
- 👤 Kiyohide Ogasawara
- 👤 Hiroshi Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:09
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/242; G11B7/244; G11B7/246; G11B7/248; G11B3/00; G11B3/68; G11B3/70; G11B3/705; G11B3/707; G11B7/004; G11B7/0045; G11B7/00452; G11B7/249; G11B7/2492; G11B7/252; G11B7/257; G11B2007/25705; G11B2007/25706; G11B2007/2571; G11B2007/25715; G11B2007/25718; G11B7/253; G11B7/2533; G11B7/2534; G11B7/254; G11B7/2542; G11B7/2572; G11B7/2575; G11B7/2578; G11B7/258; G11B7/2595
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
189 words
An optical information recording medium comprising: a transparent disk-shape substrate on which pre-grooves are concentrically or helically formed with a depth of 1450-2050 angstroms; an optical absorbing layer with an absorbance of 0.7-0.9 made of a palladium phthalocyanine dye formed on a surface of said substrate, the absorbing layer having a plurality of pits each having a changed reflectivity being duty-cycle modulated in response to a limited waveform which is formed by a recording method comprising the steps of: adding a first FM carrier having a first center frequency and a first frequency band and at least one of a second FM carrier and a third pulse carrier to each other, said second FM carrier having a second center frequency lower than said first center frequency and a second frequency band spaced from said first frequency band, said third pulse carrier having a pulse-repetition frequency lower than said second center frequency and a third frequency band spaced from said second frequency band, to form a frequency-division multiplex signal; and symmetrically clipping said frequency-division multiplex signal to form said limited waveform; and reflecting layer formed on said optical absorbing layer.
Claim 2
Dependent Claim
189 words
An optical information recording medium comprising: a transparent disk-shape substrate on which pre-grooves are concentrically or helically formed with a depth of 1450-2050 angstroms; an optical absorbing layer with an absorbance of 0.7-0.9 made of a palladium phthalocyanine dye formed on a surface of said substrate, the absorbing layer having a plurality of pits each having a changed reflectivity being duty-cycle modulated in response to a limited waveform which is formed by a recording method comprising the steps of: adding a first FM carrier having a first center frequency and a first frequency band and at least one of a second FM carrier and a third pulse carrier to each other, said second FM carrier having a second center frequency lower than said first center frequency and a second frequency band spaced from said first frequency band, said third pulse carrier having a pulse-repetition frequency lower than said second center frequency and a third frequency band spaced from said second frequency band, to form a frequency-division multiplex signal; and symmetrically clipping said frequency-division multiplex signal to form said limited waveform; and reflecting layer formed on said optical absorbing layer.
Claim 3
Dependent Claim
17 words
An optical information recording medium according claim 1, wherein said pre-groove has a width of 0.35-0.55 micrometer.
Claim 4
Independent Claim
241 words
A method for recording information as pits to an optical information recording medium comprising: a transparent disk-shape substrate on which pre-grooves are concentrically or helically formed with a depth of 1450-2050 angstroms; an optical absorbing layer with an absorbance of 0.7-0.9 made of a palladium phthalocyanine dye formed on a surface of said substrate; and a reflecting layer formed on said optical absorbing layer, which comprises steps of: forming a first FM carrier having a first center frequency and a first frequency band, forming at least one of a second FM carrier and a third pulse carrier; said second FM carrier having a second center frequency lower than said first center frequency and a second frequency band spaced from said first frequency band, said third pulse carrier having a pulse-repetition frequency lower than said second center frequency and a third frequency band spaced from said second frequency band, adding at least one of said second FM carrier and said third pulse carrier to said first FM carrier to form a frequency-division multiplex signal; and symmetrically clipping said frequency-division multiplex signal to form a limited waveform; irradiating a laser beam turning on and off in response to said limited waveform onto said optical absorbing layer of said optical information recording medium rotating at a linear velocity of 10.1-11.4 m/sec. along said pre-groove to form a plurality of pits each having a changed reflectivity being duty-cycle modulated in response to said limited waveform.
Claim 5
Independent Claim
241 words
A method for recording information as pits to an optical information recording medium comprising: a transparent disk-shape substrate on which pre-grooves are concentrically or helically formed with a depth of 1450-2050 angstroms; an optical absorbing layer with an absorbance of 0.7-0.9 made of a palladium phthalocyanine dye formed on a surface of said substrate; and a reflecting layer formed on said optical absorbing layer, which comprises steps of: forming a first FM carrier having a first center frequency and a first frequency band, forming at least one of a second FM carrier and a third pulse carrier; said second FM carrier having a second center frequency lower than said first center frequency and a second frequency band spaced from said first frequency band, said third pulse carrier having a pulse-repetition frequency lower than said second center frequency and a third frequency band spaced from said second frequency band, adding at least one of said second FM carrier and said third pulse carrier to said first FM carrier to form a frequency-division multiplex signal; and symmetrically clipping said frequency-division multiplex signal to form a limited waveform; irradiating a laser beam turning on and off in response to said limited waveform onto said optical absorbing layer of said optical information recording medium rotating at a linear velocity of 10.1-11.4 m/sec. along said pre-groove to form a plurality of pits each having a changed reflectivity being duty-cycle modulated in response to said limited waveform.
Claim 6
Dependent Claim
17 words
An optical information recording medium according claim 3, wherein said pre-groove has a width of 0.35-0.55 micrometer.
References Cited (Backward Citations)
US5075146A
Cited
US5200947A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-06-19 | 1998-12-19 | 1999-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-06-19 | 2002-12-19 | 2003-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-06-19 | 2006-12-19 | 2007-06-20 | $7700.00 | Window Closed / Lapsed |