US5590111A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of controlling recording of optical records
Assignee: Hitachi Consumer Electronics Co Ltd
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Filing: 1993-07-13
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Granted: 1996-12-31
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Expires: 2013-07-13
Abstract
Abstract In a write control method on an optical recording, at least one shift amount selected from the defocus amount of a laser beam on a recording medium, the shift amount of a recording position on a recording track and the shift amount of laser power during recording is controlled such that the selected amount falls within a predetermined range. Subsequently, a trial signal is trially recorded at a plurality of trial zones on the recording medium by using a laser power value as a parameter. The recorded trial signal is read and a difference ΔV between center levels of a highest density waveform and a lowest density waveform is detected. In connection with each trial zone, the laser power value when a reading trial signal which makes the difference ΔV minimum is recorded is defined as an optimum recording power value. Regular data is recorded at a predetermined storage area on the recording medium by using an optimum laser power value determined in connection with a trial zone closest to the predetermined storage area.
Inventors
- 👤 Fumiyoshi Kirino
- 👤 Takeshi Maeda
- 👤 Hiroshi Ide
- 👤 Toshimitsu Kaku
- 👤 Seiichi Mita
- 👤 Kazuo Shigematsu
- 👤 Tsuyoshi Toda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:45
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/12; G11B7/125; G11B7/126; G11B11/00; G11B11/10; G11B11/105; G11B11/10502; G11B11/1053; G11B11/10595; G11B20/00; G11B20/10; G11B20/10009; G11B20/10046; G11B20/10212; G11B20/18; G11B20/1816; G11B7/004; G11B7/0045; G11B7/1267; G11B11/10504; G11B11/10506; G11B11/10508; G11B20/12; G11B20/1217; G11B20/1258; G11B7/24; G11B7/2407; G11B7/24085
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
202 words
A control method of controlling recording and reproducing of optical records in an optical magnetic disk apparatus using a mark length recording method, comprising the steps of: recording a predetermined test pattern on a recording medium; reproducing said predetermined test pattern; controlling at least one shift amount selected from a defocus amount of a laser beam on a recording medium, a position shift amount of a recording position on a track at which recording is performed on said recording medium and a power shift amount of laser power irradiated during recording, to reduce a distortion of the reproduced said predetermined test pattern to less than a first predetermined value; obtaining control information under various environments in which optical recording and reproducing are performed, by repeating said steps of recording, reproducing said predetermined test patterns and controlling; recording general data on said recording medium by setting an optimum pulse width or an optimum laser power for recording on a basis of said control information; and reproducing said general data by subjecting a reproduced said general data to wave-equalizing processing, to reduce a distortion of said general data reproduced to less than a second predetermined value which is less than said first predetermined value.
Claim 2
Dependent Claim
202 words
A control method of controlling recording and reproducing of optical records in an optical magnetic disk apparatus using a mark length recording method, comprising the steps of: recording a predetermined test pattern on a recording medium; reproducing said predetermined test pattern; controlling at least one shift amount selected from a defocus amount of a laser beam on a recording medium, a position shift amount of a recording position on a track at which recording is performed on said recording medium and a power shift amount of laser power irradiated during recording, to reduce a distortion of the reproduced said predetermined test pattern to less than a first predetermined value; obtaining control information under various environments in which optical recording and reproducing are performed, by repeating said steps of recording, reproducing said predetermined test patterns and controlling; recording general data on said recording medium by setting an optimum pulse width or an optimum laser power for recording on a basis of said control information; and reproducing said general data by subjecting a reproduced said general data to wave-equalizing processing, to reduce a distortion of said general data reproduced to less than a second predetermined value which is less than said first predetermined value.
Claim 3
Dependent Claim
57 words
A control method according to claim 1 wherein, in said controlling step, a characteristic to be controlled when recording and reading of said predetermined test pattern are performed is said defocus amount of a laser beam on said recording medium during recording of said test pattern, and said defocus amount is adjusted to ±0.05 μm or less.
Claim 4
Dependent Claim
61 words
A control method according to claim 1 wherein, in said controlling step, a characteristic to be controlled when recording and reading of said predetermined test pattern are performed is said position shift amount of a recording position on a track at which recording is done on said recording medium, and said position shift amount is adjusted to ±0.10 μm or less.
Claim 5
Dependent Claim
55 words
A control method according to claim 1 wherein, in said controlling step, a characteristic to be controlled when recording and reading of said predetermined test pattern are performed is said power shift amount of laser power irradiated on said recording medium during recording, and said power shift amount is adjusted to ±0.20 mW or less.
Claim 6
Dependent Claim
36 words
A control method according to claim 1 wherein a system for providing information to an edge portion of an information recording pit is used as a system for recording said general data on said recording medium.
Claim 7
Dependent Claim
55 words
A control method according to claim 1 wherein for determination of said control information, a predetermined recording pattern is trially recorded in advance of recording, the recorded said predetermined recording pattern is reproduced, and a reproduced said predetermined recording pattern is compared with reference information stored in a predetermined table to determine said control information.
Claim 8
Dependent Claim
74 words
A control method according to claim 1 wherein a medium including a magnetic film having vertical magnetic anisotropy is used as said recording medium to perform recording in a direction of magnetization of said vertically magnetized film, and recorded information is reproduced by using a magneto-optical effect to thereby perform recording and reading, a shape of a magnetic domain to be formed in said recording medium being controlled to control a read-out signal waveform.
Claim 9
Dependent Claim
20 words
A control method according to claim 2, wherein said defocus amount is more specifically adjusted to ±0.30 μm or less.
Claim 10
Dependent Claim
21 words
A control method according to claim 3, wherein said position shift amount is more specifically adjusted to ±0.80 μm or less.
Claim 11
Dependent Claim
21 words
A control method according to claim 4, wherein said power shift amount is more specifically adjusted to ±0.10 mW or less.
References Cited (Backward Citations)
JPS61239441A
Cited
US5410527A
Cited
US4979162A
Cited
JPH0322223A
Cited
US5305297A
Cited
US5329512A
Cited
US5305296A
Cited
US5398227A
Cited
US5381396A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-12-31 | 2000-07-01 | 2000-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-12-31 | 2004-07-01 | 2004-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-12-31 | 2008-07-01 | 2008-12-31 | $7700.00 | Window Closed / Lapsed |