Patent JPS6460132A successfully refreshed from Google Patents.
EP0352974A2
Expired / Lapsed
EP
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Polarization independent optical amplifier apparatus
Assignee: AT&T Inc
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Filing: 1989-07-20
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Granted: —
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Expires: 2009-07-20
Abstract
Abstract An optical amplifier (12) is used in a double-pass configuration; that is, the output of the amplifier is passed through a 45° Faraday rotator (16.1) to a mirror (16.2) and then through the rotator and the amplifier again. Polarization independent gain is thus achieved.
Inventors
- 👤 Nils Anders Olsson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 07:19
CPC Classifications
G; G02; G02F; G02F2/00; H; H01; H01S; H01S5/00; H01S5/50; H01S5/5009; H01S5/5018; G02F1/00; G02F1/01; G02F1/09; G02F1/093; Y; Y10; Y10S; Y10S372/00; Y10S372/703
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
99 words
Optical amplifier apparatus comprising an optical amplifier (12) which has different gain for TE and TM modes of said optical radiation, and means (14,20) for transmitting both polarizations of said radiation through said amplifier, CHARACTERISED BY means (16.1, 16.2) located external to any resonator for rotating both of said polarizations of said radiation by n90°, where n is an odd integer, after it emanates from said amplifier and for transmitting said polarization-rotated radiation through said amplifier again so that the gains of said TE and TM modes passing through said amplifier an even number of times are substantially equal.
Claim 2
Dependent Claim
99 words
Optical amplifier apparatus comprising an optical amplifier (12) which has different gain for TE and TM modes of said optical radiation, and means (14,20) for transmitting both polarizations of said radiation through said amplifier, CHARACTERISED BY means (16.1, 16.2) located external to any resonator for rotating both of said polarizations of said radiation by n90°, where n is an odd integer, after it emanates from said amplifier and for transmitting said polarization-rotated radiation through said amplifier again so that the gains of said TE and TM modes passing through said amplifier an even number of times are substantially equal.
Claim 3
Dependent Claim
63 words
The apparatus of claim 1 wherein said rotating means comprises a rotator (16.1) and a mirror (16.2) arranged in tandem with said amplifier, said rotator being effective to rotate the polarization of said radiation by 45° in a single-pass therethrough and said mirror is positioned to reflect said polarization-rotated radiation for re-transmission through said amplifier, thereby to experience another 45° of polarization rotation.
Claim 4
Dependent Claim
15 words
The apparatus of claim 1 or 2 wherein said amplifier comprises a semiconductor optical amplifier.
Claim 5
Dependent Claim
12 words
The apparatus of claim 3 wherein said semiconductor optical amplifier is non-resonant.
Claim 6
Independent Claim
17 words
The apparatus of any of the preceding claims wherein said rotating means includes a Faraday optical rotator.
Claim 7
Independent Claim
23 words
The apparatus of any of the preceding claims wherein said transmitting means comprises an optical coupler for coupling said radiation of said amplifier.
Claim 8
Independent Claim
25 words
The apparatus of any of claims 1 to 5 wherein said transmitting means comprises a polarization-independent optical circulator for coupling said radiation to said amplifier.
References Cited (Backward Citations)
No citation records indexed.
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