US 5,088,095 A · Gain stabilized fiber amplifier

Abstract

In this invention an optical fiber doped with a rare earth element and coupled to be pumped with a laser is coupled to an optical feedback loop. The feedback loop couples the output signal of the fiber amplifier to the input of the fiber amplifier. A narrow bandwidth filter coupled to the feedback loop allows a selected wavelength of the amplified spontaneous emission to pass from the output of the fiber amplifier to the input of the fiber amplifier. The feedback signal has a wavelength which is different from that of the pump signal and the wavelengths of the signals to be amplified. In operation, when bursts of optical signals from at least two discrete word or frequency division multiplexed channels are amplified in the fiber amplifier, the undesired fluctuations of gain of the output signals normally due to transient saturation of the erbium-doped filter amplifier are substantially eliminated.

Claims9

Dependent claims

An fiber amplifier comprising

an optical fiber doped with a rare earth element,
a pump means coupled to pump said doped optical fiber,
an input port adapted to couple signals to said optical fiber,
an optical feedback loop interposed between the output of said doped optical fiber and the input port of said doped optical fiber,
wavelength selective means coupled to said optical feedback loop to pass a signal having a frequency other than the frequency of the pump means and the frequency of the signals applied to said input port, and
an output port coupled to receive the signal amplified by said doped optical fiber.

3 more elements

Dependencies are inferred from the claim text.

Gain stabilized fiber amplifier

Life of this patent

Gain stabilized fiber amplifier

Life of this patent

Abstract

Claims9