§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
US5404415A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical fiber coupler and method for preparing same

Assignee: Shin-Etsu Chemical Co Ltd
•
Filing: 1994-01-25
•
Granted: 1995-04-04
•
Expires: 2014-01-25
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In an optical fiber coupler comprising a plurality of optical fibers bundled together and a light-coupling portion which is formed by partially fusing and drawing these bundled fibers and which permits branching of light rays incident upon one of these fibers into the other fibers at a predetermined branching ratio, the optical fiber coupler has a difference between the branching ratio thereof determined immediately after the fusing and drawing operation and that determined after accommodating the coupler in a protective case and then adhering it to the case, equal to or less than 5%. Such an optical fiber coupler can be produced by bundling a plurality of optical fibers 1 and 2, fusing and drawing a part of the bundled optical fibers with heating, fixing the relative positions of these optical fibers 1 and 2 immediately after the fusing and drawing operation and then accommodating in and fixing to a protective case. If the foregoing difference in the branching ratio is not more than 5%, the difference between the branching ratios determined after the fusing and drawing operation and determined after the coupler is subjected to a thermal shock test is reduced to a level of not more than 2%. Therefore, the coupler does not suffer from any substantial change in properties even after the thermal shock test and thus can practically be used with high reliability.

Inventors

  • 👤 Tsuneo Mori
  • 👤 Kazuo Koya

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 05:02
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/26; G02B6/28; G02B6/2804; G02B6/2821; G02B6/2835

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 94 words
An optical fiber coupler comprising a plurality of optical fibers bundled together and a light-coupling portion which is formed by partially fusing and drawing these bundled fibers and which permits branching of light rays incident upon one of these fibers into the other fibers at a predetermined branching ratio, wherein the optical fiber coupler has a difference between the branching ratio thereof determined immediately after the fusion and drawing operation and that determined after accommodating the coupler in a protective container and then adhering it to the case, equal to or less than 5%.
Claim 2
Dependent Claim 94 words
An optical fiber coupler comprising a plurality of optical fibers bundled together and a light-coupling portion which is formed by partially fusing and drawing these bundled fibers and which permits branching of light rays incident upon one of these fibers into the other fibers at a predetermined branching ratio, wherein the optical fiber coupler has a difference between the branching ratio thereof determined immediately after the fusion and drawing operation and that determined after accommodating the coupler in a protective container and then adhering it to the case, equal to or less than 5%.
Claim 3
Independent Claim 122 words
A method for producing an optical fiber coupler which comprises the steps of bundling a plurality of optical fibers, optically coupling a part of the bundled optical fibers by fusing and drawing a part thereof with heating and accommodating the product thus obtained in a protective case, wherein the relative positions of these optical fibers are fixed immediately after the fusing and drawing operation and then the optical fiber coupler thus fixed is accommodated in the protective case, said optical fiber coupler having a difference between the branching ratio thereof determined immediately after the fusion and drawing operation and that determined after accommodating the coupler in a protective container and then adhering it to the case, equal to or less than 5%.
Claim 4
Independent Claim 122 words
A method for producing an optical fiber coupler which comprises the steps of bundling a plurality of optical fibers, optically coupling a part of the bundled optical fibers by fusing and drawing a part thereof with heating and accommodating the product thus obtained in a protective case, wherein the relative positions of these optical fibers are fixed immediately after the fusing and drawing operation and then the optical fiber coupler thus fixed is accommodated in the protective case, said optical fiber coupler having a difference between the branching ratio thereof determined immediately after the fusion and drawing operation and that determined after accommodating the coupler in a protective container and then adhering it to the case, equal to or less than 5%.
Claim 5
Dependent Claim 50 words
The method as set forth in claim 2 wherein the fixation of the relative positions of these optical fibers is carried out by adhering each optical fiber to a fixing member with an adhesive and then the resulting assembly inclusive of the fixing member is accommodated in the protective case.
Claim 6
Dependent Claim 16 words
The method as set forth in claim 3 wherein the adhesive is a UV-curing epoxy resin.
Claim 7
Dependent Claim 55 words
The method as set forth in claim 2 wherein the fixation of the relative positions of these optical fibers is carried out by accommodating the optical fibers in the protective case while fixing these optical fibers to temporary jigs, then adhering these fibers to the protective case with an adhesive and then unfastening the jigs.
Claim 8
Dependent Claim 16 words
The method as set forth in claim 5 wherein the adhesive is a UV-curing epoxy resin.

References Cited (Backward Citations)

US4822128A Cited
US5009478A Cited
JPH02220008A Cited
US5309536A Cited
US5208883A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-04-03 1998-10-03 1999-04-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-04-03 2002-10-03 2003-04-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-04-03 2006-10-03 2007-04-04 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag