US3737236A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetooptic readout system utilizing optical waveguide fibers
Assignee: Corning Glass Works
•
Filing: 1972-01-03
•
Granted: 1973-06-05
•
Expires: 1992-01-03
Abstract
Abstract Optical waveguide fibers are utilized in a magnetooptic readout system for magnetic disk file applications to maintain high resolution capabilities of plane polarized light beams. In one type of system, a first waveguide fiber transmits the light beam from a source to a magnetized storage medium and a second waveguide fiber transmits the reflected light beam from the magnetized storage medium to a combination analyzer-detector. The waveguide fibers may be of the self-focusing type with the point of focus being maintained at the magnetized medium. In another type of system, a single waveguide fiber is utilized to transmit the light beam from the source and back to the analyzer-detector. The end of the waveguide fiber adjacent the magnetized medium is coated with a magnetic film having a low coercive field. The light beam is reflected from the film which lies within the flux lines generated by the magnetized medium and undergoes a polarization reversal.
Inventors
- 👤 N Borrelli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:28
CPC Classifications
G; G11; G11C; G11C13/00; G11C13/04; G11C13/06; G02; G02F; G02F1/00; G02F1/01; G02F1/09; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/10502; G11B11/10515; G11B11/10532; G11B11/10541; G11B11/10543; G11B11/10545; G11B11/10547; G11B11/1055; G11B11/1058; G11B7/00; G11B7/12; G11B7/122
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
108 words
A system for the magnetooptic readout of information stored on a magnetized medium comprising: a source of a plane polarized light beam directed toward said magnetized medium, the plane of polarization being rotated in response to the magnetization representing the information stored on said magnetized medium; a means for determining the rotation of said plane of polarization upon receiVing said light beam from said magnetized medium; and an optical wave guide means positioned in the path between said source and said means for determining the rotation of said plane of polarization, said wave guide maintaining the resolution of said light beam to permit readout of said stored information.
Claim 2
Independent Claim
108 words
A system for the magnetooptic readout of information stored on a magnetized medium comprising: a source of a plane polarized light beam directed toward said magnetized medium, the plane of polarization being rotated in response to the magnetization representing the information stored on said magnetized medium; a means for determining the rotation of said plane of polarization upon receiVing said light beam from said magnetized medium; and an optical wave guide means positioned in the path between said source and said means for determining the rotation of said plane of polarization, said wave guide maintaining the resolution of said light beam to permit readout of said stored information.
Claim 3
Dependent Claim
26 words
The system of claim 1 wherein said wave guide means comprises a fiber having a core for transmitting said light beam and cladding surrounding said core.
Claim 4
Dependent Claim
21 words
The system of claim 2 wherein said wave guide means does not alter the plane of polarization of said light beam.
Claim 5
Dependent Claim
48 words
The system of claim 2 wherein said optical wave guide means comprises a first wave guide extending from said source substantially to said magnetized medium and a second wave guide extending substantially from said magnetized medium to said means for determining the rotation of said plane of polarization.
Claim 6
Dependent Claim
76 words
The system of claim 4 wherein said first wave guide and said second wave guide are of the self-focusing type having a refractive index profile in the radial direction such that the light is continually being brought to a focus within said first wave guide and said second wave guide, the end of said first wave guide adjacent said magnetized medium being spaced from said magnetized medium so as to focus said beam on said medium.
Claim 7
Dependent Claim
90 words
The system of claim 2 wherein said wave guide means comprises a single wave guide coated at the end adjacent said magnetized medium with a magnetic film having a low coercive field, said film lying within the flux lines of said magnetized medium, said light beam traveling through said wave guide toward said magnetized medium, being reflected by said film, and traveling through said wave guide away from said film, the plane of polarization of said light beam being rotated at said film under the influence of said flux lines.
Claim 8
Dependent Claim
51 words
The system of claim 6 further comprising a beam splitter located at the end of said wave guide remote from said magnetized medium, said beam splitter separating the portion of said light beam traveling to said film from the portion of said light beam reflected by and traveling from said film.
Claim 9
Independent Claim
178 words
A system for the magnetooptic readout of a bit of information stored on a limited area of a magnetized surface, said system comprising: a source including a focusing lens of a plane polarized light beam directed toward said magnetized surface, said source being located a large distance from said magnetic surface relative to the size of said limited area; a means including an analyzer and a detector for determining the rotation of said plane of polarization of said light beam after said beam has passed through the magnetic flux lines in the vicinity of said limited area on said magnetic surface, said means receiving said beam in a highly resolved state a large distance from said magnetized surface relative to the size of said limited area; and an optical wave guide means extending along the path of said light beam from said source, through said flux lines, and to said means for determining the rotation of said polarization, said wave guide means maintaining a high degree of resolution of said light beam without altering the plane of polarization.
Claim 10
Independent Claim
178 words
A system for the magnetooptic readout of a bit of information stored on a limited area of a magnetized surface, said system comprising: a source including a focusing lens of a plane polarized light beam directed toward said magnetized surface, said source being located a large distance from said magnetic surface relative to the size of said limited area; a means including an analyzer and a detector for determining the rotation of said plane of polarization of said light beam after said beam has passed through the magnetic flux lines in the vicinity of said limited area on said magnetic surface, said means receiving said beam in a highly resolved state a large distance from said magnetized surface relative to the size of said limited area; and an optical wave guide means extending along the path of said light beam from said source, through said flux lines, and to said means for determining the rotation of said polarization, said wave guide means maintaining a high degree of resolution of said light beam without altering the plane of polarization.
Claim 11
Dependent Claim
31 words
The system of claim 8 wherein said wave guide means comprises a core surrounded by cladding, said core having a cross sectional area at least as small as said limited area.
Claim 12
Dependent Claim
51 words
The system of claim 8 wherein the distance between said wave guide means and said magnetized surface is small relative to the distance between said source and said magnetized surface and relative to the distance between said means for determining the rotation of said plane of polarization and said magnetized surface.
References Cited (Backward Citations)
US3434774A
Cited
US3614197A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |