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US5048908A
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Method of producing apparatus comprising a low-reflection optical fiber connection
Assignee: Nokia Bell Labs
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Filing: 1990-02-13
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Granted: 1991-09-17
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Expires: 2010-02-13
Abstract
Abstract It has been discovered that tilted optical fiber endfaces useful in low-reflection optical fiber joints can be produced by cleaving, provided the fiber is twisted through an appropriate twist angle. By way of example, for a particular, commercially available single mode fiber, the normalized twist angle typically is in the range of 5-15 degrees/cm, resulting in a nominal tilt angle of the fiber endface in the approximate range 5-20 degrees.
Inventors
- 👤 Greg E. Blonder
- 👤 Bertrand H. Johnson
- 👤 Carl R. Paola
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:39
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/42; G02B6/4201; G02B6/4204; G02B6/4207; G02B6/241; G02B6/243; G02B6/26; G02B6/262; G02B6/36; G02B6/38; G02B6/3807; G02B6/381; G02B6/3818; G02B6/3822; Y; Y10; Y10S; Y10S83/00; Y10S83/913; Y10T; Y10T225/00; Y10T225/30; Y10T225/307; Y10T225/321; Y10T225/325
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
179 words
Method of producing apparatus that comprises a low-reflection optical fiber joint, the method comprising a) providing a length of optical fiber; b) shaping a first end of the optical fiber such that a tilted fiber endface results; c) incorporating the first end of the optical fiber into the optical fiber joint; and d) completing producing the apparatus; characterized in that step b) comprises applying a torque to the optical fiber at or near the first end such that an end of a portion of the optical fiber is twisted through a predetermined twist angle θ relative to the other end of the portion, applying a predetermined axial tensile force to the fiber such that the portion of the optical fiber is under axial tensile stress, the tensile stress being greater than about 4200 gm/mm 2 , and contacting the fiber with cleaving means such that the fiber separates at a point along the portion of the optical fiber, the value of θ selected such that the resulting tilted endface has a nominal tilt angle φ in the range 3°-20°.
Claim 2
Dependent Claim
179 words
Method of producing apparatus that comprises a low-reflection optical fiber joint, the method comprising a) providing a length of optical fiber; b) shaping a first end of the optical fiber such that a tilted fiber endface results; c) incorporating the first end of the optical fiber into the optical fiber joint; and d) completing producing the apparatus; characterized in that step b) comprises applying a torque to the optical fiber at or near the first end such that an end of a portion of the optical fiber is twisted through a predetermined twist angle θ relative to the other end of the portion, applying a predetermined axial tensile force to the fiber such that the portion of the optical fiber is under axial tensile stress, the tensile stress being greater than about 4200 gm/mm 2 , and contacting the fiber with cleaving means such that the fiber separates at a point along the portion of the optical fiber, the value of θ selected such that the resulting tilted endface has a nominal tilt angle φ in the range 3°-20°.
Claim 3
Dependent Claim
30 words
Method of claim 1, wherein the apparatus comprises a semiconductor laser, and wherein the fiber joint comprises an optical signal-transmissive connection between the laser and the length of optical fiber.
Claim 4
Dependent Claim
34 words
Method of claim 1, wherein the apparatus comprises a semiconductor laser, and wherein the fiber joint comprises an optical signal-transmissive connection between said length of optical fiber and a further length of optical fiber.
Claim 5
Dependent Claim
29 words
Method of claim 1, wherein the value of θ is selected such that reflected optical power is at most -40 db of the optical power incident on the endface.
References Cited (Backward Citations)
US4473942A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-09-16 | 1995-03-18 | 1995-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-09-16 | 1999-03-18 | 1999-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-09-16 | 2003-03-18 | 2003-09-17 | $7700.00 | Window Closed / Lapsed |