US5347408A
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Magnetic recording and reproducing method and apparatus with vertical magnetization component reduction
Assignee: Canon Inc
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Filing: 1992-01-30
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Granted: 1994-09-13
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Expires: 2012-01-30
Abstract
Abstract A digital signal to be recorded is converted into a digital signal having a suppressed low-frequency spectrum and having a shortest recording wavelength greater than half an original shortest recording wavelength, and the converted digital signal is recorded on a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated. The digital signal is reproduced from the magnetic recording medium in which the plurality of metal evaporated films having different crystal-growth directions are laminated. Waveform equalization is performed on the reproduced digital signal, and integration detection is performed on the waveform-equalized digital signal, thereby restoring an original digital signal.
Inventors
- 👤 Makoto Gohda
- 👤 Shinichi Yamashita
- 👤 Yasuyuki Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:26
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; G11B5/85; G11B20/00; G11B20/10; G11B20/10009; G11B5/02; G11B5/09; G11B5/62; G11B5/64; G11B5/66; G11B5/674; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/928; Y10T; Y10T428/00; Y10T428/12; Y10T428/12465
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
91 words
A magnetic recording method comprising the steps of: converting a digital signal to be recorded into a digital signal having a suppressed low-frequency spectrum and having a shortest recording wavelength greater than half an original shortest recording wavelength; and recording the converted digital signal on a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction to a surface thereof are substantially zero in total.
Claim 2
Dependent Claim
91 words
A magnetic recording method comprising the steps of: converting a digital signal to be recorded into a digital signal having a suppressed low-frequency spectrum and having a shortest recording wavelength greater than half an original shortest recording wavelength; and recording the converted digital signal on a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction to a surface thereof are substantially zero in total.
Claim 3
Dependent Claim
62 words
A method according to claim 1, wherein the plurality of metal evaporated films are an even number of metal evaporated films, crystal-growth directions in adjacent ones of the metal evaporated films being opposite to each other with respect to a surface of the magnetic recording medium and making substantially the same angle with respect to the surface of the magnetic recording medium.
Claim 4
Dependent Claim
101 words
A method according to claim 1, wherein the plurality of metal evaporated films are an odd number of metal evaporated films which are not less than three metal evaporated films, crystal-growth directions in adjacent ones of the metal evaporated films being opposite to each other with respect to a surface of the magnetic recording medium, and an angle which a crystal-growth direction in an odd-numbered metal evaporated film makes with the surface of the magnetic recording medium being smaller than an angle which a crystal-growth direction in an even-numbered metal evaporated film makes with the surface of the magnetic recording medium.
Claim 5
Dependent Claim
83 words
A magnetic reproducing method comprising the steps of: reproducing a digital signal from a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total; performing waveform equalization on the reproduced digital signal; and performing integration detection on the waveform-equalized digital signal to restore an original digital signal.
Claim 6
Dependent Claim
83 words
A magnetic reproducing method comprising the steps of: reproducing a digital signal from a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total; performing waveform equalization on the reproduced digital signal; and performing integration detection on the waveform-equalized digital signal to restore an original digital signal.
Claim 7
Dependent Claim
62 words
A method according to claim 4, wherein the plurality of metal evaporated films are an even number of metal evaporated films, crystal-growth directions in adjacent ones of the metal evaporated films being opposite to each other with respect to a surface of the magnetic recording medium and making substantially the same angle with respect to the surface of the magnetic recording medium.
Claim 8
Dependent Claim
101 words
A method according to claim 4, wherein the plurality of metal evaporated films are an odd number of metal evaporated films which are not less than three metal evaporated films, crystal-growth directions in adjacent ones of the metal evaporated films being opposite to each other with respect to a surface of the magnetic recording medium, and an angle which a crystal-growth direction in an odd-numbered metal evaporated film makes with the surface of the magnetic recording medium being smaller than an angle which a crystal-growth direction in an even-numbered metal evaporated film makes with the surface of the magnetic recording medium.
Claim 9
Dependent Claim
111 words
A magnetic recording and reproducing method comprising the steps of: converting a digital signal to be recorded into a digital signal having a suppressed low-frequency spectrum; recording the converted digital signal on a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total; reproducing the digital signal from the magnetic recording medium; performing waveform equalization on the reproduced digital signal; and performing integration detection on the waveform-equalized digital signal to restore an original digital signal.
Claim 10
Dependent Claim
111 words
A magnetic recording and reproducing method comprising the steps of: converting a digital signal to be recorded into a digital signal having a suppressed low-frequency spectrum; recording the converted digital signal on a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total; reproducing the digital signal from the magnetic recording medium; performing waveform equalization on the reproduced digital signal; and performing integration detection on the waveform-equalized digital signal to restore an original digital signal.
Claim 11
Dependent Claim
100 words
A magnetic recording apparatus comprising: (a) inputting means for receiving a digital signal as its input; (b) converting means for converting the digital signal inputted from said inputting means into a digital signal having a suppressed low-frequency spectrum; and (c) recording means for recording the digital signal outputted from said converting means on a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total.
Claim 12
Dependent Claim
100 words
A magnetic recording apparatus comprising: (a) inputting means for receiving a digital signal as its input; (b) converting means for converting the digital signal inputted from said inputting means into a digital signal having a suppressed low-frequency spectrum; and (c) recording means for recording the digital signal outputted from said converting means on a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total.
Claim 13
Dependent Claim
94 words
A magnetic reproducing apparatus comprising: (a) reproducing means for reproducing a digital signal from a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total; (b) waveform equalization means for performing waveform equalization on the reproduced digital signal; and (c) integration detection means for performing integration detection on the waveform-equalized digital signal to restore an original digital signal.
Claim 14
Dependent Claim
94 words
A magnetic reproducing apparatus comprising: (a) reproducing means for reproducing a digital signal from a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total; (b) waveform equalization means for performing waveform equalization on the reproduced digital signal; and (c) integration detection means for performing integration detection on the waveform-equalized digital signal to restore an original digital signal.
Claim 15
Dependent Claim
147 words
A magnetic recording and reproducing apparatus comprising: (a) inputting means for receiving a digital signal as its input; (b) converting means for converting the digital signal inputted from said inputting means into a digital signal having a suppressed low-frequency spectrum; (c) recording means for recording the digital signal outputted from said converting means on a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total; (d) reproducing means for reproducing the digital signal from the magnetic recording medium; (e) waveform equalization means for performing waveform equalization on the reproduced digital signal; and (f) integration detection means for performing integration detection on the waveform-equalized digital signal to restore an original digital signal.
Claim 16
Dependent Claim
147 words
A magnetic recording and reproducing apparatus comprising: (a) inputting means for receiving a digital signal as its input; (b) converting means for converting the digital signal inputted from said inputting means into a digital signal having a suppressed low-frequency spectrum; (c) recording means for recording the digital signal outputted from said converting means on a magnetic recording medium in which a plurality of metal evaporated films having different crystal-growth directions are laminated, wherein magnetization components of the plurality of metal evaporated films of said magnetic recording medium in a vertical direction relative to a surface thereof are substantially zero in total; (d) reproducing means for reproducing the digital signal from the magnetic recording medium; (e) waveform equalization means for performing waveform equalization on the reproduced digital signal; and (f) integration detection means for performing integration detection on the waveform-equalized digital signal to restore an original digital signal.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-09-12 | 1998-03-14 | 1998-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-12 | 2002-03-14 | 2002-09-13 | $3760.00 | Window Closed / Lapsed |
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