US4842359A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical star coupler and method of manufacturing the same
Assignee: Hitachi Ltd
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Filing: 1987-12-09
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Granted: 1989-06-27
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Expires: 2007-12-09
Abstract
Abstract An optical star coupler having a biconically tapered optical star coupler suspensively inserted in a protection tube and the method for manufacturing the same are disclosed, and the manufacturing method is that an optical fiber bundle is inserted into a protection tube such as hollow glass tube, then the optical fiber bundle is twisted and pulled while it is indirectly heated through the protection tube, thereby to form a twisting, fusing and pulling portion, and both ends of the protection tube are sealed with an adhesive agent to fix the optical fiber bundle to the protection tube. This optical star coupler can be constructed so as to be connected in tandem without any splicing. The optical star coupler of the present invention, naturally in the case of an optical star coupler using multi-mode optical fiber, particularly in the case of one equally divided optical star coupler using single-mode optical fiber, also provides low insertion loss, less power deviation and low manufacturing cost.
Inventors
- 👤 Katsuyuki Imoto
- 👤 Minoru Maeda
- 👤 Masayoshi Kameyama
- 👤 Yasushi Ikuta
- 👤 Hiroshi Araki
- 👤 Shigeru Oho
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:19
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/26; G02B6/28; G02B6/2804; G02B6/2856; G02B6/2821; G02B6/2835; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
72 words
An optical star coupler comprising: a protection tube; a plurality of optical fibers suspended in said protection tube, having a twisting, fusing and pulling portion at a central portion of said optical fibers and twisting and fusing portions on both sides, of said twisting, fusing and pulling portion; and means for fixing said optical fibers on both ends of said protection tube, wherein said optical fibers are further covered with plastic material.
Claim 2
Dependent Claim
72 words
An optical star coupler comprising: a protection tube; a plurality of optical fibers suspended in said protection tube, having a twisting, fusing and pulling portion at a central portion of said optical fibers and twisting and fusing portions on both sides, of said twisting, fusing and pulling portion; and means for fixing said optical fibers on both ends of said protection tube, wherein said optical fibers are further covered with plastic material.
Claim 3
Dependent Claim
31 words
An optical star coupler as claimed in claim 1, wherein the diameter of said protection tube is thinner in substantially the center of said protection tube than at other portions thereof.
Claim 4
Dependent Claim
26 words
An optical star coupler as claimed in claim 1, wherein the outer diameter at both ends of said protection tube is thinner than other portions thereof.
Claim 5
Dependent Claim
17 words
An optical star coupler as claimed in claim 1, wherein said protection tube is a semicircular tube.
Claim 6
Independent Claim
104 words
A method of making an optical star coupler, comprising the steps of: inserting a plurality of optical fibers into a protection tube so as to be suspended therein; twisting said optical fibers; fusing substantially the central portion of said optical fibers by heating said optical fibers through said protection tube; pulling said optical fibers while heating said optical fibers through said protetion tube; fusing both sides of said substantially the central portion of said optical fibers by heating said optical fibers through said protection tube; fixing said optical fibers on both ends of said protection tube; and covering said optical fibers with plastic material.
Claim 7
Independent Claim
104 words
A method of making an optical star coupler, comprising the steps of: inserting a plurality of optical fibers into a protection tube so as to be suspended therein; twisting said optical fibers; fusing substantially the central portion of said optical fibers by heating said optical fibers through said protection tube; pulling said optical fibers while heating said optical fibers through said protetion tube; fusing both sides of said substantially the central portion of said optical fibers by heating said optical fibers through said protection tube; fixing said optical fibers on both ends of said protection tube; and covering said optical fibers with plastic material.
Claim 8
Dependent Claim
40 words
A method of making an optical star coupler as claimed in claim 5, wherein said step of twisting said optical fibers includes the step of rotating chucks around the axis of said optical fibers in opposite directions to each other.
Claim 9
Dependent Claim
39 words
A method of making an optical star coupler as claimed in claim 5, wherein said step of pulling said optical fibers includes the step of moving headstocks using headstock driving mechanisms in opposite directions for pulling the optical fibers.
Claim 10
Dependent Claim
48 words
An optical star coupler comprising: a protection tube; a plurality of optical fibers suspended in said protection tube, having a twisting, fusing and pulling portion covered with plastic material separate from said protection tube; and means for fixing said optical fibers on both ends of said protection tube.
Claim 11
Dependent Claim
48 words
An optical star coupler comprising: a protection tube; a plurality of optical fibers suspended in said protection tube, having a twisting, fusing and pulling portion covered with plastic material separate from said protection tube; and means for fixing said optical fibers on both ends of said protection tube.
Claim 12
Dependent Claim
31 words
An optical star coupler as claimed in claim 8, wherein the diameter of said protection tube is thinner in substantially the center of said protection tube than at other portions thereof.
Claim 13
Dependent Claim
26 words
An optical star coupler as claimed in claim 8, wherein the outer diameter of both ends of said protection tube is thinner than other portions thereof.
References Cited (Backward Citations)
US4087157A
Cited
US4123138A
Cited
US4291940A
Cited
US4360248A
Cited
US4449781A
Cited
US4330170A
Cited
US4457581A
Cited
EP0171479A1
Cited
US4726643A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-06-26 | 1992-12-26 | 1993-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-26 | 1996-12-26 | 1997-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-26 | 2000-12-26 | 2001-06-27 | $7700.00 | Window Closed / Lapsed |