Patent EP0186299A2 successfully refreshed from Google Patents.
EP0186299A2
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EP
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Optical amplifier
Assignee: Nortel Networks Ltd
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Filing: 1985-11-15
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Granted: —
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Expires: 2005-11-15
Abstract
Abstract @ An optical signal pulse to be amplified and a pump signal pulse are launched consecutively into one end of an optical fibre, which may comprise a separate fibre or part of a transmission line. The pulses differ in wavelength by one or more Stokes shift and the order of launch is determined by the relevant group velocities in the fibre. Owing to dispersion in the fibre the pulses overlap and overtake one another while they are transmitted along the fibre, the signal pulse being amplified as a result of Raman stimulated emission and compressed as a result of power depletion from the pump pulse, thus increasing the bandwidth of the transmission line.
Inventors
- 👤 Kevin Christopher Byron
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 07:39
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/39; G02F1/395; H; H01; H01S; H01S3/00; H01S3/30; H01S3/302
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
97 words
An optical amplifier for amplifying an optical signal pulse, characterised in that the amplifier comprises a length of optical fibre, a pump signal pulse source, the pump and optical signal pulse wavelengths differing by one or more Stokes shift, and means for launching the pump and optical signal pulses consecutively into one end of the fibre, the order of launching being determined by their relative group velocities in the fibre, the optical signal pulse being amplified and compressed, by depletion of power in the pump signal pulse, upon overlap of the pulses in use of the amplifier.
Claim 2
Dependent Claim
97 words
An optical amplifier for amplifying an optical signal pulse, characterised in that the amplifier comprises a length of optical fibre, a pump signal pulse source, the pump and optical signal pulse wavelengths differing by one or more Stokes shift, and means for launching the pump and optical signal pulses consecutively into one end of the fibre, the order of launching being determined by their relative group velocities in the fibre, the optical signal pulse being amplified and compressed, by depletion of power in the pump signal pulse, upon overlap of the pulses in use of the amplifier.
Claim 3
Dependent Claim
24 words
An optical amplifier as claimed in claim 1 characterised in that the optical signal pulse wavelength comprises the zero dispersion wavelength of the fibre.
Claim 4
Dependent Claim
32 words
An optical amplifier as claimed in claim 2, characterised in that the optical fibre is of silica, the optical signal pulse wavelength is 1.3pm and the pump signal pulse wavelength is 1.24pm.
Claim 5
Dependent Claim
34 words
An optical amplifier as claimed in claim 1 characterised in that in use pulse spreading of the signal pulse during transmission through the fibre is at least partially compensated for by said pulse compression.
Claim 6
Dependent Claim
24 words
An optical amplifier as claimed in any one of the preceding claims characterised in that the pump signal pulse source includes a semiconductor laser.
Claim 7
Dependent Claim
32 words
A optical amplifier as claimed in any one of the preceding claims characterised in that the fibre is of such a length as to allow the pulses to overtake one another completely.
Claim 8
Independent Claim
118 words
A method of amplifying a first pulsed optical signal, which is of a first wavelength, characterised by the steps of generating a pulsed pump signal, which is of a second wavelength, the first and second wavelengths differing by one or more Stokes shift, and launching the first pulsed optical signal and the pulsed pump signal consecutively into one end of a length of optical fibre, the order of launching being determined by their relative group velocities in the fibre, Raman stimulated emission in the fibre upon overlap of the pulses serving to induce gain in the first optical signal, the amplified first optical signal being of reduced pulse width owing to power depletion in the pump signal pulse.
Claim 9
Independent Claim
118 words
A method of amplifying a first pulsed optical signal, which is of a first wavelength, characterised by the steps of generating a pulsed pump signal, which is of a second wavelength, the first and second wavelengths differing by one or more Stokes shift, and launching the first pulsed optical signal and the pulsed pump signal consecutively into one end of a length of optical fibre, the order of launching being determined by their relative group velocities in the fibre, Raman stimulated emission in the fibre upon overlap of the pulses serving to induce gain in the first optical signal, the amplified first optical signal being of reduced pulse width owing to power depletion in the pump signal pulse.
Claim 10
Dependent Claim
21 words
A method as claimed in claim 7 characterised in that the first wavelength comprises the zero dispersion wavelength of the fibre.
Claim 11
Dependent Claim
22 words
A method as claimed in claim 7 or claim 8, characterised in that the pump signal is generated by a semiconductor laser.
Claim 12
Dependent Claim
29 words
A method as claimed in claim 7 to 9, characterised in that the fibre is of such a length as to allow the pulses to overtake one another completely.
References Cited (Backward Citations)
No citation records indexed.
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