US4667316A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Information recording-reproducing apparatus
Assignee: Canon Inc
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Filing: 1984-03-07
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Granted: 1987-05-19
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Expires: 2004-03-07
Abstract
Abstract An information recording-reproducing apparatus provided with a first light beam for recording information on a recording medium and a monitoring second light beam for reproducing the recorded information simultaneously with the recording is characterized in that when only the reproduction of already recorded information is effected, a focus control signal or a tracking control signal is obtained by the use of the first light beam.
Inventors
- 👤 Shigeyuki Suda
- 👤 Yukichi Niwa
- 👤 Yasuo Ogino
- 👤 Eigo Kawakami
- 👤 Mitsutoshi Ohwada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:55
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B7/12
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
100 words
An information recording-reproducing apparatus comprising: means for generating a first light beam for recording information on a recording medium during a recording; means for generating a monitoring second light beam for reproducing the recorded information simultaneously with the recording; first detecting means for obtaining one of a focus control signal and a tracking control signal from the first light beam during a reproduction time when only reproduction of the recorded information is effected; and second detecting means for obtaining the other of the focus control signal and the tracking control signal from the second light beam during said reproduction time.
Claim 2
Dependent Claim
100 words
An information recording-reproducing apparatus comprising: means for generating a first light beam for recording information on a recording medium during a recording; means for generating a monitoring second light beam for reproducing the recorded information simultaneously with the recording; first detecting means for obtaining one of a focus control signal and a tracking control signal from the first light beam during a reproduction time when only reproduction of the recorded information is effected; and second detecting means for obtaining the other of the focus control signal and the tracking control signal from the second light beam during said reproduction time.
Claim 3
Dependent Claim
43 words
An information recording-reproducing apparatus according to claim 1, wherein when only reproduction is effected, a tracking control signal is obtained by the use of said first light beam and a focus control signal is obtained by the use of said second light beam.
Claim 4
Dependent Claim
54 words
An information recording-reproducing apparatus according to claim 2, wherein said focus control signal is obtained by causing said second light beam to enter so that the principal ray thereof forms a certain angle from a direction perpendicular to the surface of the recording medium and detecting the positional deviation of the reflected light thereof.
Claim 5
Dependent Claim
52 words
An information recording-reproducing apparatus according to claim 3, wherein the beam spot of said second light beam, as compared with the beam spot of said first light beam, is of an elliptical shape elongated in a direction perpendicular to the direction of movement of the beam spot relative to the recording medium.
Claim 6
Dependent Claim
52 words
An information recording-reproducing apparatus according to claim 2, wherein the beam spot diameter of said second light beam, as compared with the beam spot diameter of said first light beam, is large with respect to a direction perpendicular to the direction of movement of the beam spot relative to the recording medium.
Claim 7
Dependent Claim
26 words
An information recording-reproducing apparatus according to claim 1 or 2, wherein a focus control signal is obtained from said second light beam when information is recorded.
Claim 8
Dependent Claim
42 words
An information recording-reproducing apparatus according to claim, 1 or 2, wherein said recording medium is provided with a tracking guide in advance, and a tracking control signal is obtained from said first light beam when information is recorded on said recording medium.
Claim 9
Dependent Claim
24 words
An information recording-reproducing apparatus according to claim 7, wherein a focus control signal is obtained from said second light beam when information is recorded.
Claim 10
Dependent Claim
26 words
An information recording-reproducing apparatus according to claim 1 or 2, wherein a reproducing signal is obtained from said second light beam when only reproduction is effected.
Claim 11
Dependent Claim
26 words
An information recording-reproducing apparatus according to claim 1 or 2, wherein said first light beam and said second light beam differ in wavelength from each other.
Claim 12
Dependent Claim
26 words
An information recording-reproducing apparatus according to claim 10, wherein the wavelength of said second light beam is longer than the wavelength of said first light beam.
Claim 13
Dependent Claim
43 words
An information recording-reproducing apparatus according to claim 1, wherein when only reproduction is effected, a focus control signal is obtained by the use of said first light beam and a tracking control signal is obtained by the use of said second light beam.
Claim 14
Dependent Claim
37 words
An information recording-reproducing apparatus according to claim 12, wherein the beam spot diameter of said second light beam when only reproduction is effected is smaller than the beam spot diameter thereof when recording of information is effected.
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) | 1990-05-18 | 1990-11-17 | 1991-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-18 | 1994-11-17 | 1995-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-18 | 1998-11-17 | 1999-05-19 | $7700.00 | Window Closed / Lapsed |