US4028081A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacturing helical optical fiber
Assignee: AT&T Inc
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Filing: 1976-09-28
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Granted: 1977-06-07
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Expires: 1996-09-28
Abstract
Abstract An optical cable which is relatively immune to the effects of bending and/or tension comprises a helical optical fiber loosely confined within a protective sheath. Apparatus is disclosed for fabricating the helical fiber. For example, as the fiber is drawn from a heated preform the fiber is subjected to periodic, pulsating jets of an inert gas, such as nitrogen, which physically deform the fiber into the desired helical configuration.
Inventors
- 👤 Enrique Alfredo Jose Marcatili
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:27
CPC Classifications
C; C03; C03B; C03B37/00; C03B37/01; C03B37/02; C03B37/025; C03B37/027; C03B37/022; C03B37/02718; C03B37/03; C03B37/032; C03B37/10; C03B37/14; C03C; C03C25/00; C03C25/10; C03C25/104; C03C25/106; G; G02; G02B; G02B6/00; G02B6/44; G02B6/4479; G02B6/448; B; B29; B29C; B29C70/00; B29C70/68; B29C70/685; B29C70/687; C03B2203/00; C03B2203/02; C03B2203/06; C03B2203/10; C03B2203/18; C03B2203/20; C03B2203/36
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
88 words
A method of manufacturing an optical fiber in the form of an elongated helix, comprising the steps of: heating the lower extremity of a substantially vertically disposed preform to soften the preform; and drawing the optical fiber from said softened preform, said method being characterized by the further steps of: passing said optical fiber, while still in a softened state, through at least one pair of eccentrically rotatable rollers; and rotating said rollers in synchronism with the rate at which said fiber is drawn from the softened preform.
Claim 2
Independent Claim
88 words
A method of manufacturing an optical fiber in the form of an elongated helix, comprising the steps of: heating the lower extremity of a substantially vertically disposed preform to soften the preform; and drawing the optical fiber from said softened preform, said method being characterized by the further steps of: passing said optical fiber, while still in a softened state, through at least one pair of eccentrically rotatable rollers; and rotating said rollers in synchronism with the rate at which said fiber is drawn from the softened preform.
Claim 3
Dependent Claim
57 words
The method according to claim 1 wherein said fiber passing step comprises: passing said fiber through at least one pair of eccentrically rotatable rollers, each of said rollers having a diameter such that, as the rollers deform the fiber, a helical fiber is formed having a pitch l o and a diameter d, where l o >>d.
Claim 4
Independent Claim
117 words
A method of manufacturing an optical fiber in the form of an elongated helix which comprises the steps of: heating the lower extremity of a substantially vertically disposed preform to soften the preform; and drawing the optical fiber from said softened preform, said method being characterized by the further steps of: positioning an upper portion of said preform within an aperture formed in a fixed member; positioning a lower portion of said preform within an aperture formed in a movable member; and moving said movable member in an oscillatory manner with respect to said fixed member whereby a corresponding oscillatory movement is induced in said preform, which oscillatory movement generates the desired helical configuration for the fiber.
Claim 5
Independent Claim
117 words
A method of manufacturing an optical fiber in the form of an elongated helix which comprises the steps of: heating the lower extremity of a substantially vertically disposed preform to soften the preform; and drawing the optical fiber from said softened preform, said method being characterized by the further steps of: positioning an upper portion of said preform within an aperture formed in a fixed member; positioning a lower portion of said preform within an aperture formed in a movable member; and moving said movable member in an oscillatory manner with respect to said fixed member whereby a corresponding oscillatory movement is induced in said preform, which oscillatory movement generates the desired helical configuration for the fiber.
Claim 6
Dependent Claim
88 words
The method according to claim 3 wherein first and second transducers are mounted between said fixed and movable members and symmetrically disposed with respect to said preform, the method being characterized by the further steps of: applying a sinusoidal signal to the first transducer to energize the same; and simultaneously applying a sinusoidal signal to the second transducer to energize the same, the signal applied to said second transducer being of the same frequency as the signal which is applied to said first transducer but 180° out-of-phase therewith.
Claim 7
Dependent Claim
83 words
The method according to claim 4 wherein third and fourth transducers are mounted between said fixed and movable members and symmetrically disposed with respect to said preform but orthogonally oriented with respect to said first and second transducers, the method being characterized by the further steps of: applying sinusoidal signals to said third and fourth transducers which are 180° out-of-phase with one another but which have a fixed, 90° phase-shift with respect to the sinusoidal signals applied to said first and second transducers.
Claim 8
Independent Claim
99 words
A method of manufacturing an optical fiber in the form of an elongated helix, comprising the steps of: heating the lower extremity of a substantially vertically disposed preform to soften the preform; and drawing the optical fiber from said softened preform, characterized in that said preform heating step comprises: rotating a heat-source about said preform, the axis of rotation of said heat-source being parallel to, but spaced apart from, the longitudinal axis of said preform whereby said preform is asymmetrically heated, thereby to induce preferential melting of the preform and the desired helical configuration of the fiber drawn therefrom.
Claim 9
Independent Claim
99 words
A method of manufacturing an optical fiber in the form of an elongated helix, comprising the steps of: heating the lower extremity of a substantially vertically disposed preform to soften the preform; and drawing the optical fiber from said softened preform, characterized in that said preform heating step comprises: rotating a heat-source about said preform, the axis of rotation of said heat-source being parallel to, but spaced apart from, the longitudinal axis of said preform whereby said preform is asymmetrically heated, thereby to induce preferential melting of the preform and the desired helical configuration of the fiber drawn therefrom.
Claim 10
Dependent Claim
25 words
The method according to claim 6 characterized in that said heat-source rotating step comprises rotating a focused beam of coherent, collimated radiation onto said preform.
Claim 11
Independent Claim
66 words
A method of converting a conventional optical fiber into an optical fiber having the configuration of a helix, characterized by the steps of: advancing said fiber past a source of heat to soften the fiber; passing said softened fiber through at least one pair of eccentrically rotatable rollers; and rotating said rollers in synchronism with the rate at which said fiber is drawn from the preform.
Claim 12
Independent Claim
66 words
A method of converting a conventional optical fiber into an optical fiber having the configuration of a helix, characterized by the steps of: advancing said fiber past a source of heat to soften the fiber; passing said softened fiber through at least one pair of eccentrically rotatable rollers; and rotating said rollers in synchronism with the rate at which said fiber is drawn from the preform.
Claim 13
Independent Claim
99 words
A method of converting a conventional optical fiber into an optical fiber having the configuration of a helix, characterized by the steps of: advancing said fiber past a source of heat to soften the fiber; passing said fiber through an aperture in a first guide means positioned upstream of said heat-source; passing said softened fiber through an aperture in a second guide means positioned downstream of said heat-source; and rotating said second guide means in a plane which is normal to the longitudinal axis of said fiber thereby rotating said aperture and inducing a helical twist in said fiber.
Claim 14
Independent Claim
99 words
A method of converting a conventional optical fiber into an optical fiber having the configuration of a helix, characterized by the steps of: advancing said fiber past a source of heat to soften the fiber; passing said fiber through an aperture in a first guide means positioned upstream of said heat-source; passing said softened fiber through an aperture in a second guide means positioned downstream of said heat-source; and rotating said second guide means in a plane which is normal to the longitudinal axis of said fiber thereby rotating said aperture and inducing a helical twist in said fiber.
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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) | 1980-06-06 | 1980-12-06 | 1981-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-06 | 1984-12-06 | 1985-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-06 | 1988-12-06 | 1989-06-07 | $7700.00 | Window Closed / Lapsed |