US4525822A
Expired / Lapsed
US
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Optical data recordation and reproduction system
Assignee: Fujifilm Business Innovation Corp
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Filing: 1982-03-04
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Granted: 1985-06-25
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Expires: 2002-03-04
Abstract
Abstract An optical data recordation and reproduction system comprising a first optical means modulates a light beam with digitized data and impacts this modulated light beam onto a photosensitive material, producing discontinuities in the photosensitive material corresponding to the data. A second optical means then directs a beam of unmodulated light onto this photosensitive material, and converts the resulting modulated light into an electric signal. An electric circuit then differentiates and samples the signal, producing the recorded digitized data via self-locking.
Inventors
- 👤 Nobuo Nishimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:28
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/2407; G11B7/24085; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1423
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
120 words
An optical data recordation and reproduction system, comprising: first optical means including modulation means wherein a beam of light from a source is frequency modulated by digital data such that a recording signal is produced corresponding to said digital data having a pulse width equal to at least a signal period, said modulated light impacting upon a photosensitive recording medium to produce discontinuities in said medium which correspond to the data to be recorded; a second optical means, in which a beam of unmodulated light directed onto said photosensitive medium is received and is converted to an electrical signal; and an electrical circuit comprising a differentiator in which said electrical signal is differentiated and sampled to uncover said recorded data.
Claim 2
Dependent Claim
120 words
An optical data recordation and reproduction system, comprising: first optical means including modulation means wherein a beam of light from a source is frequency modulated by digital data such that a recording signal is produced corresponding to said digital data having a pulse width equal to at least a signal period, said modulated light impacting upon a photosensitive recording medium to produce discontinuities in said medium which correspond to the data to be recorded; a second optical means, in which a beam of unmodulated light directed onto said photosensitive medium is received and is converted to an electrical signal; and an electrical circuit comprising a differentiator in which said electrical signal is differentiated and sampled to uncover said recorded data.
Claim 3
Dependent Claim
32 words
An optical data recordation and reproduction system as in claim 1, wherein said light beam used in both said first optical means and said second optical means originates from a common source.
Claim 4
Dependent Claim
35 words
An optical data recordation and reproduction system as in claim 1, in which said second optical means includes an electrical means which continually stabilizes said unmodulated light beam during operation of said second optical means.
Claim 5
Dependent Claim
46 words
An optical data recordation and reproduction system as in claim 1, further comprising modulation means for modifying the frequency modulation of said light in which the pulse width of a recording signal corresponding to said digital data is set equal to at least a signal period.
Claim 6
Dependent Claim
53 words
An optical data recording and reproduction system of claim 1 wherein said beam of unmodulated light is reflected from said recording medium and onto said second optical means, a photodector coupled to said second optical means for converting said reflected beam into an electrical signal or variations in intensity of said reflected beam.
Claim 7
Dependent Claim
130 words
An optical data recordation and reproduction system, comprising: first optical means, in which a beam of light from a source is modulated by digital data to be recorded and impacts upon a photosensitive recording medium such that discontinuities in said medium are created which correspond to the data to be recorded; a second optical means, in which a beam of unmodulated light directed onto said photosensitive medium is received and is converted to an electrical signal; an electrical circuit comprising a differentiator in which said electrical signal is differentiated and sampled to uncover said recorded data; and modulation means for modifying the frequency modulation of said light in which the pulse width of a recording signal corresponding to said digital data is set equal to at least a signal period.
Claim 8
Dependent Claim
130 words
An optical data recordation and reproduction system, comprising: first optical means, in which a beam of light from a source is modulated by digital data to be recorded and impacts upon a photosensitive recording medium such that discontinuities in said medium are created which correspond to the data to be recorded; a second optical means, in which a beam of unmodulated light directed onto said photosensitive medium is received and is converted to an electrical signal; an electrical circuit comprising a differentiator in which said electrical signal is differentiated and sampled to uncover said recorded data; and modulation means for modifying the frequency modulation of said light in which the pulse width of a recording signal corresponding to said digital data is set equal to at least a signal period.
Claim 9
Dependent Claim
32 words
An optical data recordation and reproduction system as in claim 6, wherein said light beam used in both said first optical means and said second optical means originates from a common source.
Claim 10
Dependent Claim
34 words
An optical recordation and reproduction system as in claim 6, in which said second optical means includes an electrical means which continually stabilizes said unmodulated light beam during operation of said second optical means.
Claim 11
Dependent Claim
53 words
An optical data recording and reproduction system of claim 6, wherein said beam of unmodulated light is reflected from said recording medium and onto said second optical means, a photodetector coupled to said second optical means for converting said reflected beam into an electrical signal or variations in intensity of said reflected beam.
Claim 12
Dependent Claim
165 words
An optical data recordation and reproduction system, comprising: first optical means including modulation means wherein a beam of light from a source is frequency modulated by digital data such that a recording signal is produced corresponding to said digital data having a pulse width equal to at least a signal period, said modulated light impacting upon a photosensitive recording medium to produce discontinuities in said medium which correspond to the data to be recorded; a second optical means, in which a beam of unmodulated light directed onto said photosensitive medium is received and is converted to an electrical signal; and an electrical circuit, in which said electrical signal is differentiated and sampled to uncover said recorded data, comprising a low pass filter receiving said electrical signal, said filter producing an output to a differentiator and a limiter respectively, clock means receiving the output of said limiter and, discriminator means for comparing the output of said differentiator and a sampling signal from said clock means operation.
Claim 13
Dependent Claim
165 words
An optical data recordation and reproduction system, comprising: first optical means including modulation means wherein a beam of light from a source is frequency modulated by digital data such that a recording signal is produced corresponding to said digital data having a pulse width equal to at least a signal period, said modulated light impacting upon a photosensitive recording medium to produce discontinuities in said medium which correspond to the data to be recorded; a second optical means, in which a beam of unmodulated light directed onto said photosensitive medium is received and is converted to an electrical signal; and an electrical circuit, in which said electrical signal is differentiated and sampled to uncover said recorded data, comprising a low pass filter receiving said electrical signal, said filter producing an output to a differentiator and a limiter respectively, clock means receiving the output of said limiter and, discriminator means for comparing the output of said differentiator and a sampling signal from said clock means operation.
Claim 14
Dependent Claim
174 words
An optical data recordation and reproduction system, comprising: first optical means, in which a beam of light from a source is modulated by digital data to be recorded and impacts upon a photosensitive recording medium such that discontinuities in said medium are created which correspond to the data to be recorded; a second optical means, in which a beam of unmodulated light directed onto said photosensitive medium is received and is converted to an electrical signal; an electrical circuit, in which said electrical signal is differentiated and sampled to uncover said recorded data comprising a low pass filter receiving said electrical signal, said filter producing an output to a differentiator and a limiter respectively, clock means receiving the output of said limiter and, discriminator means comparing the output of said differentiator and a sampling signal from said clock means operation; and modulation means for modifying the frequency modulation of said light in which the pulse width of a recording signal corresponding to said digital data is set equal to at least a signal period.
Claim 15
Dependent Claim
174 words
An optical data recordation and reproduction system, comprising: first optical means, in which a beam of light from a source is modulated by digital data to be recorded and impacts upon a photosensitive recording medium such that discontinuities in said medium are created which correspond to the data to be recorded; a second optical means, in which a beam of unmodulated light directed onto said photosensitive medium is received and is converted to an electrical signal; an electrical circuit, in which said electrical signal is differentiated and sampled to uncover said recorded data comprising a low pass filter receiving said electrical signal, said filter producing an output to a differentiator and a limiter respectively, clock means receiving the output of said limiter and, discriminator means comparing the output of said differentiator and a sampling signal from said clock means operation; and modulation means for modifying the frequency modulation of said light in which the pulse width of a recording signal corresponding to said digital data is set equal to at least a signal period.
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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) | 1988-06-24 | 1988-12-24 | 1989-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-24 | 1992-12-24 | 1993-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-24 | 1996-12-24 | 1997-06-25 | $7700.00 | Window Closed / Lapsed |