Patent US3903360A successfully refreshed from Google Patents.
US3903360A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reduction by polarization noise techniques
Assignee: Panasonic Holdings Corp
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Filing: 1973-10-05
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Granted: 1975-09-02
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Expires: 1993-10-05
Abstract
Abstract An apparatus for recording and reproducing signals in which a reference flux of coherent light and each of two kinds of fluxes of light separated from the reference flux of light are interfered with one another so as to form a multiple recording through a slit on a moving recording medium, and fluxes of reproduction light diffracted from said multiple recorded medium are individually converted into electrical signals which are then electrically superposed to give a time series signal.
Inventors
- 👤 Kosey Kamisaka
- 👤 Makoto Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:34
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/004; G11B7/0065
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
306 words
Apparatus for recording signals on and reproducing signals from an optical image recording medium, comprising: means for generating a beam of coherent light for recording signals on said recording medium; means located in the path of said coherent light beam for splitting said beam into primary and secondary beams and for directing said primary beam onto said recording medium; means for generating a time-series electrical signal; electro-optical means coupled to the output of said time-series signal generating means and located in the path of said secondary beam for modulating said secondary beam as a function of said time-series signal; further means located in the path of said secondary beam for splitting said modulated beam into first and second parts and for directing said first and second modulated beam parts onto said recording medium at predetermined angles with respect to each other and to said primary beam; first and second analyzer located in the paths of said first and second modulated secondary beam parts, respectively, and having respective polarization angles theta 1 and theta 2 relative to the plane of polarization of said secondary beam; means comprising a slit located in front of said recording medium through which said primary beam and said modulated secondary beam parts pass to produce an interference pattern on said recording medium between said primary beam and said modulated secondary beam parts after the latter have passed through said analyzers; means for generating a reproducing beam of coherent light and projecting said producing beam onto said recording medium; first and second photoelectric transducing means for detecting poRtions of the reproduced light beam corresponding to said recorded first and second secondary beam parts, respectively, and generating electrical signals corresponding to said detected beams; and means for combining the outputs of said photoelectric transducing means for reproducing said time-series signal from said recording medium.
Claim 2
Dependent Claim
306 words
Apparatus for recording signals on and reproducing signals from an optical image recording medium, comprising: means for generating a beam of coherent light for recording signals on said recording medium; means located in the path of said coherent light beam for splitting said beam into primary and secondary beams and for directing said primary beam onto said recording medium; means for generating a time-series electrical signal; electro-optical means coupled to the output of said time-series signal generating means and located in the path of said secondary beam for modulating said secondary beam as a function of said time-series signal; further means located in the path of said secondary beam for splitting said modulated beam into first and second parts and for directing said first and second modulated beam parts onto said recording medium at predetermined angles with respect to each other and to said primary beam; first and second analyzer located in the paths of said first and second modulated secondary beam parts, respectively, and having respective polarization angles theta 1 and theta 2 relative to the plane of polarization of said secondary beam; means comprising a slit located in front of said recording medium through which said primary beam and said modulated secondary beam parts pass to produce an interference pattern on said recording medium between said primary beam and said modulated secondary beam parts after the latter have passed through said analyzers; means for generating a reproducing beam of coherent light and projecting said producing beam onto said recording medium; first and second photoelectric transducing means for detecting poRtions of the reproduced light beam corresponding to said recorded first and second secondary beam parts, respectively, and generating electrical signals corresponding to said detected beams; and means for combining the outputs of said photoelectric transducing means for reproducing said time-series signal from said recording medium.
Claim 3
Dependent Claim
37 words
The recording and reproducing apparatus according to claim 1, wherein said combining means comprises clipping circuits coupled to the outputs of said photoelectric transducing means and a differential amplifier coupled to the outputs of said clipping circuits.
Claim 4
Dependent Claim
23 words
The recording and reproducing apparatus according to claim 1, wherein said combining means comprises a differential amplifier coupled to said photoelectric transducing means.
Claim 5
Dependent Claim
34 words
The recording and reproducing apparatus according to claim 1, wherein said polarization angles theta 1 and theta 2 are approximately +45* and -45*, respectively, relative to the plane of polarization of said secondary beam.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-01 | 1979-03-03 | 1979-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-01 | 1983-03-03 | 1983-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-01 | 1987-03-03 | 1987-09-02 | $7700.00 | Window Closed / Lapsed |