Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
134 words
An optical amplifier comprising a first stage of amplification comprising a core of a first composition within a cladding to form an optical amplifying fiber having an input port and an output port, a second stage of amplification comprising a core of a second composition within a cladding to form an optical amplifying fiber having an input port and an output port, said first composition being different from said second composition, means for generating a pump signal at a pump wavelength coupled optically to said first and second optical amplifying fibers, and optical means interposed between the output port of said first stage of amplification and the input port of said second stage of amplification adapted to suppress reflection-induced noise and spontaneous emission from the first stage from causing saturation of the second stage.
Claim 2
Dependent Claim
48 words
The optical amplifier of claim 1 wherein one of said stages comprises an erbium doped silica fiber having a co-dopant selected from the group comprising aluminum, germanium, hafnium, holmium, titanium, zirconium and said other stage of said amplifier comprises an erbium doped silica fiber core having another composition.
Claim 3
Dependent Claim
19 words
The optical amplifier of claim 2 wherein one of said stages comprises an erbium doped fiber core of alumino-silicate.
Claim 4
Dependent Claim
41 words
The optical amplifier of claim 1 wherein said optical means comprises an optical filter adapted to pass the amplified signals and to suppress energy in the form of spontaneous emission from the first stage from causing saturation of the second stage.
Claim 5
Dependent Claim
19 words
The optical amplifier of claim 1 wherein said optical means comprises an optical isolator adapted to suppress reflection-induced noise.
Claim 6
Dependent Claim
50 words
The optical amplifier of claim 1 wherein said optical means comprises an optical filter adapted to pass the amplified signals and to suppress energy in the form of spontaneous emission from the first stage from causing saturation of the second stage, and an optical isolator adapted to suppress reflection-induced noise.
Claim 7
Dependent Claim
90 words
The optical amplifier of claim 1 wherein said means for generating a pump signal comprises a first wavelength multiplexer coupled to pass a received signal to the input port of said first stage, a first semiconductor laser diode coupled to said first wavelength multiplexer for supplying pump power to said first stage, a second wavelength multiplexer coupled to pass a received signal to the input port of said second stage, and a second semiconductor laser diode coupled to said second wavelength multiplexer for supplying pump power to said second stage.
Claim 8
Dependent Claim
44 words
The optical amplifier of claim 7 wherein said optical means comprises an optical filter adapted to suppress energy in the form of spontaneous emission from the first stage from causing saturation of the second stage, and an optical isolator adapted to suppress reflection-induced noise.