Patent US5282079A successfully refreshed from Google Patents.
US5282079A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical fibre amplifier
Assignee: Prysmian Cables and Systems Ltd
•
Filing: 1992-07-02
•
Granted: 1994-01-25
•
Expires: 2012-07-02
Abstract
Abstract An Ar + ion laser pumped optical fibre amplifier is provided with an optical fibre having a core which has been solution doped using a solution of an aluminum and an erbium salt.
Inventors
- 👤 Richard I. Laming
- 👤 Simon B. Poole
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:31
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/09; H01S3/091; H01S3/094; C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/014; C03B37/018; C03B37/01807; C03B37/01838; H01S3/05; H01S3/06; H01S3/063; H01S3/067; H01S3/06708; H01S3/14; H01S3/16; H01S3/17; C03B2201/00; C03B2201/06; C03B2201/30; C03B2201/31; C03B2201/34; C03B2201/36; H01S2301/00; H01S2301/02; H01S3/094003; H01S3/1601; H01S3/1603; H01S3/1608; H01S3/1691; H01S3/1693
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
193 words
An optical fiber amplifier for optically amplifying signals at a wavelength of about 1532 nm which has a fiber with an excited-state absorption (ESA) cross-section to ground-state absorption (GSA) cross-section ratio of less than one, said amplifier comprising: an optical fiber having ends and having a silica based inner-core, a cladding encircling said core, said core being doped with Er 3+ in an amount at least equal to 200 ppm and with alumina in an amount which will provide a refraction index which is higher than the refraction index of said cladding, said core being free of phosphorous; a pumping source coupled to an end of said fiber from supplying pumping energy at a wavelength lower than the wavelength of said signals and about 500 nm; means for supplying said signals connected to an end of said optical fiber for causing ions of said ER 3+ to fluoresce and provide signal gain; and said amplifier being without means for positive feedback at the wavelength of said signals from one part of said fiber to another part of said fiber whereby signal gain and improved pumping efficiency at said pumping energy wavelength are obtained.
Claim 2
Dependent Claim
193 words
An optical fiber amplifier for optically amplifying signals at a wavelength of about 1532 nm which has a fiber with an excited-state absorption (ESA) cross-section to ground-state absorption (GSA) cross-section ratio of less than one, said amplifier comprising: an optical fiber having ends and having a silica based inner-core, a cladding encircling said core, said core being doped with Er 3+ in an amount at least equal to 200 ppm and with alumina in an amount which will provide a refraction index which is higher than the refraction index of said cladding, said core being free of phosphorous; a pumping source coupled to an end of said fiber from supplying pumping energy at a wavelength lower than the wavelength of said signals and about 500 nm; means for supplying said signals connected to an end of said optical fiber for causing ions of said ER 3+ to fluoresce and provide signal gain; and said amplifier being without means for positive feedback at the wavelength of said signals from one part of said fiber to another part of said fiber whereby signal gain and improved pumping efficiency at said pumping energy wavelength are obtained.
Claim 3
Dependent Claim
188 words
An optical fiber amplifier for optically amplifying signals at a wavelength of about 1532 nm which has a fiber with an excited-state absorption cross-section to ground-state absorption cross-section ratio of less than one, said amplifier comprising: an optical fiber having ends and having a silica based inner-core, a cladding encircling said core, said core being doped with Er 3+ in an amount at least equal to 200 ppm and co-doped with alumina in an amount which will provide a refraction index which is higher than the refraction index of said cladding, said alumina being the major co-dopant; a pumping source coupled to an end of said fiber for supplying pumping energy at a wavelength lower than the wavelength of said signals; means for supplying said signals connected to an end of said optical fiber for causing ions of said Er 3+ to fluoresce and provide signal gain; and said amplifier being without means for positive feedback at the wavelength of said signals from one part of said fiber to another part of said fiber whereby signal gain and improved pumping efficiency at said pumping energy wavelength are obtained.
Claim 4
Dependent Claim
188 words
An optical fiber amplifier for optically amplifying signals at a wavelength of about 1532 nm which has a fiber with an excited-state absorption cross-section to ground-state absorption cross-section ratio of less than one, said amplifier comprising: an optical fiber having ends and having a silica based inner-core, a cladding encircling said core, said core being doped with Er 3+ in an amount at least equal to 200 ppm and co-doped with alumina in an amount which will provide a refraction index which is higher than the refraction index of said cladding, said alumina being the major co-dopant; a pumping source coupled to an end of said fiber for supplying pumping energy at a wavelength lower than the wavelength of said signals; means for supplying said signals connected to an end of said optical fiber for causing ions of said Er 3+ to fluoresce and provide signal gain; and said amplifier being without means for positive feedback at the wavelength of said signals from one part of said fiber to another part of said fiber whereby signal gain and improved pumping efficiency at said pumping energy wavelength are obtained.
Claim 5
Dependent Claim
24 words
An amplifier as set forth in claim 1 wherein said Er 3+ is present in said core in an amount less than 1000 ppm.
Claim 6
Dependent Claim
31 words
An amplifier as set forth in claim 1 wherein said Er 3+ is present in said core in an amount less than amount which will cause upconversion in said optical fiber.
Claim 7
Dependent Claim
17 words
An amplifier as set forth in claim 2 wherein said pumping energy wavelength is about 500 nm.
Claim 8
Dependent Claim
26 words
An amplifier as set forth in claim 2 wherein said core has been solution doped with a solution of an aluminum salt and an erbium salt.
Claim 9
Dependent Claim
16 words
An amplifier as set forth in claim 6 wherein the aluminum salt is aluminum trichloride hexahydrate.
Claim 10
Dependent Claim
16 words
An amplifier as set forth in claim 6 wherein the erbium salt is erbium trichloride hexahydrate.
Claim 11
Dependent Claim
18 words
An amplifier as set forth in claim 2 wherein said pumping source is an AR + ion laser.
Claim 12
Dependent Claim
26 words
An amplifier as set forth in claim 2 wherein said and Er 3+ and is present in said core in an amount of about 300 ppm.
References Cited (Backward Citations)
US4015217A
Cited
US3953620A
Cited
US4193879A
Cited
US4938556A
Cited
US4680048A
Cited
US4680046A
Cited
US4637025A
Cited
US4666247A
Cited
WO1986007221A1
Cited
GB2180392A
Cited
GB2199029A
Cited
US4733133A
Cited
EP0243010A1
Cited
US4751429A
Cited
WO1988002133A1
Cited
EP0286626A1
Cited
US4826288A
Cited
EP0294977A1
Cited
US4848998A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-01-24 | 1997-07-26 | 1998-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-01-24 | 2001-07-26 | 2002-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-01-24 | 2005-07-26 | 2006-01-25 | $7700.00 | Window Closed / Lapsed |