EP0409574A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Optical information recording and reproducing apparatus
Assignee: Canon Inc
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Filing: 1990-07-17
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Granted: —
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Expires: 2010-07-17
Abstract
Abstract The present invention provides an optical information recording and reproducing apparatus wherein a light beam spot is properly illuminated onto a recording medium by detecting a tracking error signal and/or a focus error signal at a time shared mode and by activating a tracking actuatorand/or a focus actuator, thereby performing the recording and reproducing of information, comprising: means for supposing an error signal on the basis of a plurality of error signals previously detected, when any error signal cannot be detected during an error signal detecting operation.
Inventors
- 👤 Tsukasa Ogino
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 09:03
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/09
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
86 words
An optical information recording and reproducing apparatus in which a light beam spot is properly illuminated onto a recording medium by detecting a tracking error signal and/or a focus error signal at a time shared mode and by activating a tracking actuator and/or a focus actuator, thereby performing the recording and reproducing of information, comprising: means for supposing an error signal on the basis of a plurality of error signals previously detected, when any error signal can not be detected during an error signal detecting operation.
Claim 2
Dependent Claim
86 words
An optical information recording and reproducing apparatus in which a light beam spot is properly illuminated onto a recording medium by detecting a tracking error signal and/or a focus error signal at a time shared mode and by activating a tracking actuator and/or a focus actuator, thereby performing the recording and reproducing of information, comprising: means for supposing an error signal on the basis of a plurality of error signals previously detected, when any error signal can not be detected during an error signal detecting operation.
Claim 3
Dependent Claim
64 words
An optical information recording and reproducing apparatus according to claim 1, wherein said supposition of an error signal is effected on the basis of an equation: Sn = (Sn-1 - Sn-2) + Sn-1 where, Sn is an error signal to be supposed Sn-1 is an error signal obtained by the prior detection, and Sn-2 is an error signal obtained by two steps prior detection.
Claim 4
Dependent Claim
80 words
An optical information recording and reproducing apparatus according to claim 1, wherein said supposition of an error signal is effected on the basis of an equation: Sn = (Sn-3 + Sn-2 + Sn-1)/3 + (Sn-1 - Sn-3) where, Sn is an error signal to be supposed, Sn-1 is an error signal obtained by the prior detection, Sn-2 is an error signal obtained by the two steps prior detection, and Sn-3 is an error signal obtained by three steps prior detection.
Claim 5
Dependent Claim
20 words
An optical information recording and reproducing apparatus according to claim 2, further including memory means for storing the error signals.
Claim 6
Dependent Claim
20 words
An optical information recording and reproducing apparatus according to claim 3, further including memory means for storing the error signals.
References Cited (Backward Citations)
No citation records indexed.
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