US4500168A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Single polarization optical fibers
Assignee: Hitachi Cable Ltd
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Filing: 1982-06-17
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Granted: 1985-02-19
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Expires: 2002-06-17
Abstract
Abstract In the single polarization optical fiber of the present invention, an elliptical jacket is composed of SiO 2 +P 2 O 5 +B 2 O 3 , whereby increase in transmission loss at long wavelength band is prevented. In the process for fabricating single polarization optical fibers of the invention, a starting silica tube is subjected to pressure reduction with an amount of pressure reduction in response to concentration of dopants P 2 O 5 +B 2 O 3 , whereby an ellipticity of the resulting elliptical jacket is made to be a pertinent value.
Inventors
- 👤 Hiroshi Kajioka
- 👤 Toshihide Tokunaga
- 👤 Junkichi Nakagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 00:27
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/10; G02B6/105; C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/018; C03B37/01861; C03B2203/00; C03B2203/30
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
128 words
In a single polarization optical fiber of the type comprising a circular core having a predetermined first refractive index; an elliptical jacket positioned on the outside of said circular core, having a predetermined second refractive index which is smaller than that of said first refractive index; and a supporting layer made of silica glass and positioned on the outside of said elliptical jacket; the improvement wherein said elliptical jacket contains dopants of B 2 O 3 and P 2 O 5 , the content of said dopants being 5-20 mol % relative to the total material forming said elliptical jacket, said B 2 O 3 being provided for decreasing the second refractive index and said P 2 O 5 being provided for lowering softening temperature and viscosity thereof.
Claim 2
Dependent Claim
128 words
In a single polarization optical fiber of the type comprising a circular core having a predetermined first refractive index; an elliptical jacket positioned on the outside of said circular core, having a predetermined second refractive index which is smaller than that of said first refractive index; and a supporting layer made of silica glass and positioned on the outside of said elliptical jacket; the improvement wherein said elliptical jacket contains dopants of B 2 O 3 and P 2 O 5 , the content of said dopants being 5-20 mol % relative to the total material forming said elliptical jacket, said B 2 O 3 being provided for decreasing the second refractive index and said P 2 O 5 being provided for lowering softening temperature and viscosity thereof.
Claim 3
Dependent Claim
37 words
A single polarization optical fiber as claimed in claim 1 wherein the mol % ratio of B 2 O 3 to P 2 O 5 in said elliptical jacket is within a range of 1:1 to 1:1.2.
Claim 4
Dependent Claim
168 words
A single polarization optical fiber comprising a circular core having a predetermined first refractive index; a circular cladding positioned on the outside of said circular core and having a predetermined second refractive index which is smaller than that of said first refractive index; and elliptical jacket positioned on the outside of said circular cladding, having a refractive index which is smaller than said first refractive index and larger than said second refractive index, and containing dopants of B 2 O 3 and P 2 O 5 , the contents of the said dopants being 5-20 mol % to the total elliptical jacket, wherein the mol % ratio of B 2 O 3 to P 2 O 5 is within the range of 1:1 to 1:1.2, said B 2 O 3 being provided for decreasing the refractive index and said P 2 O 5 being provided for lowering softening temperature and viscosity; and a supporting layer made of silica glass and positioned on the outside of said elliptical jacket.
Claim 5
Dependent Claim
168 words
A single polarization optical fiber comprising a circular core having a predetermined first refractive index; a circular cladding positioned on the outside of said circular core and having a predetermined second refractive index which is smaller than that of said first refractive index; and elliptical jacket positioned on the outside of said circular cladding, having a refractive index which is smaller than said first refractive index and larger than said second refractive index, and containing dopants of B 2 O 3 and P 2 O 5 , the contents of the said dopants being 5-20 mol % to the total elliptical jacket, wherein the mol % ratio of B 2 O 3 to P 2 O 5 is within the range of 1:1 to 1:1.2, said B 2 O 3 being provided for decreasing the refractive index and said P 2 O 5 being provided for lowering softening temperature and viscosity; and a supporting layer made of silica glass and positioned on the outside of said elliptical jacket.
Claim 6
Dependent Claim
33 words
A single polarization optical fiber as claimed in claim 3 wherein said circular cladding has a thickness which is larger than half the radius of said core and smaller than a diameter thereof.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |