Patent US4807210A successfully refreshed from Google Patents.
US4807210A
Expired / Lapsed
US
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Optical information processing apparatus
Assignee: Hitachi Ltd
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Filing: 1987-07-08
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Granted: 1989-02-21
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Expires: 2007-07-08
Abstract
Abstract An optical information processing apparatus uses an optical disk having correction marks such as mirror surfaces or wobbled pits intermittently arranged along a guide track. In a reproduce mode, tracking control is effected by correcting a tracking signal by a tracking offset component detected by the correction marks. In a record or erase mode, the track offset correction is deactivated and record or erase operation is controlled in accordance with an output level of the detected track offset component so that incomplete eraser of recorded data is prevented.
Inventors
- 👤 Toshimitsu Kaku
- 👤 Kazuo Shigematsu
- 👤 Yoshito Tsunoda
- 👤 Takeshi Maeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:21
CPC Classifications
G; G11; G11B; G11B7/00; G11B27/00; G11B27/10; G11B27/19; G11B11/00; G11B11/10; G11B11/105; G11B11/10502; G11B11/10517; G11B11/1055; G11B11/10576; G11B11/10595; G11B19/00; G11B19/02; G11B19/04; G11B27/28; G11B27/30; G11B27/3027; G11B7/08; G11B7/09; G11B7/0901; G11B7/0938; G11B2220/00; G11B2220/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
157 words
An optical information processing apparatus comprising: a record medium having a guide track and intermittently arranged correction marks; an optical system for focusing light to said record medium; modulation means for changing an intensity of the light between a reproduce mode and a record mode; a detector for detecting a light reflected by said record medium to produce an electrical signal; track error detection means for detecting a tracking signal from said electrical signal; offset detection means for detecting a track offset from said electrical signal when said light irradiates said correction marks; tracking control means connected to said track error detection means and said offset detection means for correcting the tracking signal by the track offset to effect tracking control; and control means for deactivating the correction in a record mode and comparing an output level of said offset detection means with a predetermined level and controlling said modulation means in accordance with the comparison result.
Claim 2
Dependent Claim
157 words
An optical information processing apparatus comprising: a record medium having a guide track and intermittently arranged correction marks; an optical system for focusing light to said record medium; modulation means for changing an intensity of the light between a reproduce mode and a record mode; a detector for detecting a light reflected by said record medium to produce an electrical signal; track error detection means for detecting a tracking signal from said electrical signal; offset detection means for detecting a track offset from said electrical signal when said light irradiates said correction marks; tracking control means connected to said track error detection means and said offset detection means for correcting the tracking signal by the track offset to effect tracking control; and control means for deactivating the correction in a record mode and comparing an output level of said offset detection means with a predetermined level and controlling said modulation means in accordance with the comparison result.
Claim 3
Dependent Claim
16 words
An optical information processing apparatus according to claim 1 wherein said correction marks are mirror surfaces.
Claim 4
Dependent Claim
16 words
An optical information processing apparatus according to claim 1 wherein said correction marks are wobbled pits.
Claim 5
Dependent Claim
19 words
An optical information processing apparatus according to claim 1 wherein said correction marks comprise mirror surfaces and wobbled pits.
Claim 6
Dependent Claim
61 words
An optical information processing apparatus according to claim 1 wherein said control means includes a decision circuit for comparing the output of said offset detection means with the predetermined level and a switching circuit for supplying the output of said offset detection means to said tracking control means and said decision circuit in the reproduce mode and the record mode respectively.
Claim 7
Dependent Claim
87 words
An optical information processing apparatus comprising: an optical disk having correction marks arranged in a guide track thereof; a light source; an optical system for directing a light emitted from said light source to said optical disk; a track offset detection circuit for detecting a track offset from said correction marks; and a decision circuit for checking an output level of said track offset detection circuit; record or erase operation of data to said optical disk being controlled in accordance with the output of said decision circuit.
Claim 8
Dependent Claim
87 words
An optical information processing apparatus comprising: an optical disk having correction marks arranged in a guide track thereof; a light source; an optical system for directing a light emitted from said light source to said optical disk; a track offset detection circuit for detecting a track offset from said correction marks; and a decision circuit for checking an output level of said track offset detection circuit; record or erase operation of data to said optical disk being controlled in accordance with the output of said decision circuit.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-02-21 | 1992-08-22 | 1993-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-21 | 1996-08-22 | 1997-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-21 | 2000-08-22 | 2001-02-21 | $7700.00 | Window Closed / Lapsed |