EP0245085A1
Expired / Lapsed
EP
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Optical amplifiers
Assignee: British Telecommunications PLC
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Filing: 1987-05-05
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Granted: —
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Expires: 2007-05-05
Abstract
Abstract A semiconductor travelling wave optical amplifier is presented in a new configuration. An amplifier chip (20) has the rear facet (23) provided with a reflective coating. Optical signals are input and amplified signals are output via optical fibres (21, 25, 30) and directional coupler (24). A single fibre- to-amplifier alignment is required between fibre tail (25) and the front facet (22). The front facet (22) is provided with a very low reflectivity coating. In this configuration the amplification is increased in comparison with the conventional in-line amplifier configuration.
Inventors
- 👤 Michael John O'mahony
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 10:33
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/29; H04B10/291; H04B10/2912; H04B10/2914; G; G02; G02B; G02B6/00; G02B6/24; G02B6/42; G02B6/4201; G02B6/4202; G02B6/4219; H01; H01S; H01S5/00; H01S5/50; H01S5/02; H01S5/028; H01S5/06; H01S5/068; H01S5/0683
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
52 words
An optical amplifier having first and second opposite facets provided with signal reflection means having, respectively, low and high reflectivities R 1 , R 2 , wherein the product R 1 R 2 is of the order of 10- 4 or less and R 2 is in the range 0.3 to 1.0.
Claim 2
Dependent Claim
52 words
An optical amplifier having first and second opposite facets provided with signal reflection means having, respectively, low and high reflectivities R 1 , R 2 , wherein the product R 1 R 2 is of the order of 10- 4 or less and R 2 is in the range 0.3 to 1.0.
Claim 3
Dependent Claim
64 words
An optical amplifier as claimed in claim 1 adapted so that in use an optical signal enters via the first facet, is amplified on a first traverse of the amplifier, and reflected at the high reflectivity means to return along substantially the same path as that of the first traverse so as to exit through the first facet at substantially the point of entry.
Claim 4
Dependent Claim
19 words
An optical amplifier as claimed in claim 1 or claim 2, wherein the amplifier is a travelling wave amplifier.
Claim 5
Dependent Claim
18 words
An optical amplifier as claimed in any preceding claim, wherein R 1 is less than 10- 3 :
Claim 6
Dependent Claim
17 words
An optical amplifier as claimed in claim 4, wherein R 1 is less than 10- 4 .
Claim 7
Dependent Claim
19 words
An optical amplifier as claimed in any preceding claim, wherein R 2 is in the range 0.85 to 1.00.
Claim 8
Dependent Claim
30 words
An optical amplifier as claimed in any preceding claim, wherein the product R 1 R 2 and R 1 /R 2 is of the order of 10- 6 or less.
Claim 9
Dependent Claim
27 words
An optical amplifier as claimed in any preceding claim, wherein said signal reflection means comprise low and high reflectivity surfaces on the first and second facets, respectively.
Claim 10
Dependent Claim
39 words
An optical amplifier assembly comprising an amplifier as claimed in any preceding claim and an optical waveguide located to transmit an input optical signal via the active area of the first facet, and to receive an amplified output signal.
Claim 11
Dependent Claim
32 words
An optical amplifier assembly as claimed in claim 9, including a directional coupler, one arm of which is associated with said waveguide, arranged to separate the output signal from the input signal.
Claim 12
Dependent Claim
52 words
An optical amplifier assembly according to claim 9 or claim 10, including amplifier control means comprising a controller and a detector positioned to detect a proportion of the amplified optical signal transmitted by the high reflectivity means and adapted to provide a monitor signal to the controller for controlling the amplifier gain.
References Cited (Backward Citations)
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