US 5,557,442 A · Optical amplifiers with flattened gain curves

Abstract

The present invention relates to optical systems having optical amplifiers with flattened gain curves. In one embodiment, the invention comprises an optical amplifier system having an optical input fiber and an optical amplifier device connected to receive optical input signals from the optical input fiber. A directional optical transfer device has a first port connected to receive an initial amplified output from said optical amplifier device. An optical attenuation fiber is connected to a second port of said optical transfer device, and receives the initial amplified output applied to the, first port. The optical attenuation fiber supplies an adjusted amplified output to the second port and includes plural in-fiber gratings and plural attenuators. The in-fiber gratings and attenuators are configured such that an attenuator is disposed between two in-fiber gratings. Each in-fiber gratings reflects a different wavelength of optical energy. An optical output fiber connected to a third port of the directional optical transfer device receives the adjusted amplified output.

Claims19

Dependent claims

An optical amplifier system comprising:

an optical input fiber;
an optical amplifier device connected to receive optical input signals from the optical input fiber;
a directional optical transfer device having at least first, second, and third ports, the first port connected to receive an initial amplified output from said optical amplifier device;
an optical attenuation fiber connected to the second port of said optical transfer device, said second port receiving said initial amplified output applied to said first port, said optical attenuation fiber having a plurality of in-fiber gratings and a plurality of attenuators, each of said attenuators disposed between two of the in-fiber gratings, each of said in-fiber gratings reflecting a different wavelength of optical energy, said optical attenuation fiber supplying an adjusted amplified output to said second port, the optical attenuation fiber configured such that the adjusted amplified output is a relatively linear amplification of the optical input signals;
and
an optical output fiber connected to the third port of said directional optical transfer device to receive said adjusted amplified output.

3 more elements

An optical amplifier system comprising:

an optical input fiber;
an optical amplifier device connected to receive optical input signals from the optical input fiber and provide an initial amplified output;
an optical attenuation fiber operably connected to said optical amplifier device to receive said initial amplified output, said optical attenuation fiber having a plurality of in-fiber gratings and a plurality of attenuators,
each of said attenuators disposed between two of the in-fiber gratings, each of said in-fiber gratings reflecting a different wavelength of optical energy, said optical attenuation fiber supplying a reflection which is an adjusted amplified output;
and
an optical output fiber operably connected to said optical attenuation fiber to receive said adjusted amplified output;
and
wherein said initial amplified output is a non-linear amplification of the optical input signals, and wherein said optical attenuation fiber compensates for nonlinearity in said optical amplifier device such that said adjusted amplified output is a relatively linear amplification of the optical input signals.

5 more elements

Dependencies are inferred from the claim text.

Optical amplifiers with flattened gain curves

Life of this patent

Optical amplifiers with flattened gain curves

Life of this patent

Abstract

Claims19