US5084890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pumped cw laser with low dopant level laser medium
Assignee: British Telecommunications PLC
•
Filing: 1990-11-14
•
Granted: 1992-01-28
•
Expires: 2010-11-14
Abstract
Abstract A 2.7Sg(m)m laser comprises a single mode fluoro-zirconate optical fibre doped with 0.086 mole % Er 3+ . C-W operation of the usually self-terminating lasing transition 4 I 11/2 to 4 I 13/2 is achieved by applying excitation energy to a suitable wavelength and intensity to elevate ions from the lower lasing level to maintain a population inversion between the upper and lower lasing levels during lasing. The laser may be pumped at a single wavelength of about 785 nm by a semiconductor laser.
Inventors
- 👤 Michael C. Brierley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:37
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/05; H01S3/06; H01S3/063; H01S3/067; H01S3/06708; H01S3/06716; H01S3/14; H01S3/16; H01S3/17; H01S3/09; H01S3/091; H01S3/094; H01S3/094003; H01S3/094092; H01S3/1601; H01S3/1603; H01S3/1608; H01S3/173
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
126 words
A laser comprising: a laser cavity; a laser medium disposed within the cavity, said medium including fluoro-zirconate glass hosting erbium ions at doping levels insufficient to support ion-ion interaction up-conversion, which lasing ions have an upper and a lower lasing level each above the ions' ground state which levels form a normally self-terminating laser transition, said lasing ions also having a further excitation level above said upper lasing level; and a continuous wave pumping means for applying excitation energy of a wavelength and intensity suitable to elevate ions from the lower lasing level to said further excitation level by excited state absorption to maintain a population inversion between the upper and lower lasing levels whereby cw lasing between said upper and lower lasing levels is obtainable.
Claim 2
Dependent Claim
126 words
A laser comprising: a laser cavity; a laser medium disposed within the cavity, said medium including fluoro-zirconate glass hosting erbium ions at doping levels insufficient to support ion-ion interaction up-conversion, which lasing ions have an upper and a lower lasing level each above the ions' ground state which levels form a normally self-terminating laser transition, said lasing ions also having a further excitation level above said upper lasing level; and a continuous wave pumping means for applying excitation energy of a wavelength and intensity suitable to elevate ions from the lower lasing level to said further excitation level by excited state absorption to maintain a population inversion between the upper and lower lasing levels whereby cw lasing between said upper and lower lasing levels is obtainable.
Claim 3
Dependent Claim
30 words
A laser as in claim 1 in which the excitation energy has a wavelength and intensity suitable to also elevate ions from the ground state to the upper lasing level.
Claim 4
Dependent Claim
22 words
A laser as in claim 2 in which the excitation energy corresponds to the 4 I 15/2 to 4 F 7/2 transition.
Claim 5
Dependent Claim
22 words
A laser as in claim 2 in which the excitation energy corresponds to the 4 I 15/2 to 4 I 9/2 transition.
Claim 6
Dependent Claim
18 words
A laser as in claim 1, 2, 3 or 4 in which the laser medium is a waveguide.
Claim 7
Dependent Claim
14 words
A laser as in claim 4 in which the waveguide is an optical fibre.
Claim 8
Dependent Claim
25 words
A laser as in claim 1, 2, 3, 4 or 6 in which the pumping means comprises an argon ion laser operating in all-lines mode.
Claim 9
Dependent Claim
20 words
A laser as in claim 1, 2, 3, 4 or 6 in which the pumping means is a semiconductor laser.
Claim 10
Dependent Claim
27 words
A laser as in claim 1, 2, 3 or 4 in which the erbium ion doping level does not substantially exceed 0.086 mole % Er 3+ ions.
References Cited (Backward Citations)
US4788687A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-01-27 | 1995-07-29 | 1996-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-01-27 | 1999-07-29 | 2000-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-01-27 | 2003-07-29 | 2004-01-28 | $7700.00 | Window Closed / Lapsed |