EP0281222A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Lasers and amplifiers
Assignee: STC PLC
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Filing: 1988-01-18
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Granted: —
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Expires: 2008-01-18
Abstract
Abstract Optical fibres comprised of a halide glass incorporating colour centres, for example fluoride fibres, can behave as a laser or an amplifier when maintained at a low temperature, typically 77°K, and optically pumped. A laser may be comprised by a length of such a fibre (1) wound on a spool (2) and disposed in liquid nitrogen (4), the ends of the fibre are outside of the coolant and associated with input and output mirrors (5,6) which define the extremities of a lasing cavity. An optical pumping signal (7) is provided by a laser (8), for example a Krypton ion laser operating in the visible range. The output of the fibre laser is in the infra-red. Higher gain than with conventional colour centre lasers is achieved due to the longer interaction length and cooling problems are overcome.
Inventors
- 👤 Kevin Christopher Byron
- 👤 Michael Grant Scott
- 👤 Wilson Sibbett
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 08:49
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/10; G02B6/102; H; H01; H01S; H01S3/00; H01S3/05; H01S3/06; H01S3/063; H01S3/067; H01S3/14; H01S3/16; H01S3/1681; H01S3/10; H01S3/105; H01S3/1055
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
11 words
An optical fibre comprised of a halide glass incorporating colour centres.
Claim 2
Dependent Claim
11 words
An optical fibre comprised of a halide glass incorporating colour centres.
Claim 3
Dependent Claim
23 words
An optical fibre as claimed in claim 1 characterised in that the colour centres have been incorporated in the halide glass by irradiation.
Claim 4
Dependent Claim
20 words
An optical fibre as claimed in claim 1 or claim 2 characterised in that the halide glass is a fluroride.
Claim 5
Dependent Claim
21 words
An optical fibre as claimed in claim 1 or claim 2 characterised in that the halide glass contains an alkali halide.
Claim 6
Independent Claim
47 words
An apparatus characterised by a length (1; 10) of a halide glass optical fibre incorporating colour centres, means (3,4; 12,13) for cooling the fibre to a working temperature and means (5: 18) for coupling an optical pumping signal (7; 16) into an input end of the fibre.
Claim 7
Independent Claim
47 words
An apparatus characterised by a length (1; 10) of a halide glass optical fibre incorporating colour centres, means (3,4; 12,13) for cooling the fibre to a working temperature and means (5: 18) for coupling an optical pumping signal (7; 16) into an input end of the fibre.
Claim 8
Dependent Claim
32 words
An apparatus as claimed in claim 5 characterised by a respective mirror (5,6) associated with each fibre (1) end whereby to define a lasing cavity therebetween, the apparatus comprising a fibre laser.
Claim 9
Dependent Claim
22 words
An apparatus as claimed in claim 5 or claim 6 characterised in that the halide glass optical fibre is a fluoride fibre.
Claim 10
Independent Claim
25 words
An apparatus as claimed in any one of claims 5 to 7 characterised by a laser source (8; 17) for generating the optical pumping signal.
Claim 11
Dependent Claim
19 words
An apparatus as claimed in claim 6 characterised by means for tuning the wavelength of the fibre laser output.
Claim 12
Dependent Claim
69 words
An apparatus as claimed in claim 5 characterised by means for coupling a further optical signal (14), whose wavelength comprises the wavelength at which lasing of the halide glass optical fibre can be achieved, to the input end of the fibre (10), the signal output from the other end of the fibre in use of the apparatus comprising the further opticaI signal amplified, the apparatus comprising an optical amplifier.
Claim 13
Independent Claim
36 words
An apparatus as claimed in any one of claims 5 to 10 characterised in that the means for cooling the fibre to the working temperature comprises a Dewar flask (3; 12) containing liquid nitrogen (4; 13).
Claim 14
Dependent Claim
45 words
An apparatus as claimed in claim 11 characterised in that the halide glass optical fibre (1; 10) is wound on a spool (2; 11) and immersed in the liquid nitrogen (4; 13) except for its ends which are disposed outside of the flask (3; 12).
Claim 15
Dependent Claim
30 words
A halide glass optical fibre (1) incorporating colour centres which when maintained cooled to a working temperature and optically pumped by the output of a laser (8) exhibits laser action.
Claim 16
Dependent Claim
30 words
A halide glass optical fibre (1) incorporating colour centres which when maintained cooled to a working temperature and optically pumped by the output of a laser (8) exhibits laser action.
Claim 17
Dependent Claim
52 words
A halide glass optical fibre (10) incorporating colour centres which when cooled to a working temperature and optically pumped by the output of a laser (17) serves to amplify an optical signal (14) input thereto whose wavelength comprises the wavelength at which lasing of the halide glass optical fibre can be achieved.
Claim 18
Dependent Claim
52 words
A halide glass optical fibre (10) incorporating colour centres which when cooled to a working temperature and optically pumped by the output of a laser (17) serves to amplify an optical signal (14) input thereto whose wavelength comprises the wavelength at which lasing of the halide glass optical fibre can be achieved.
References Cited (Backward Citations)
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