Power regulation in optical networks
AssigneeLucent Technologies Inc.
InventorsPhilip John Anthony, Fred Ludwig Heismann, Edmond Joseph Murphy, Timothy O. Murphy
Life of this patent
Estimating the term…
Abstract
The invention disclosed is a circuit for regulating optical power levels. Electrooptic attenuators are used to control optical output intensity by means of feedback loops from the outputs of the attenuators to the electrodes of the attenuators which determine the amount of light going to the outputs. The attenuators may be used in combination with an optical switch array in a wavelength division multiplexing system.
Claims14
A circuit for controlling optical power levels comprising:
- at least one electrically controllable optical attenuator having an input for receiving an optical input signal, at least one electrode, and an output for delivering an output signal wherein the output signal power level is normally dependent upon the polarization of the input signal;
- and
- a feedback loop comprising a photodetector optically coupled to at least a portion of the output signal and electrically coupled to the at least one electrode of the attenuator for controlling the power level of the optical output signal in response to the electrical signal from the photodetector
- whereby the feedback loop results in the power level of the output signal being essentially independent of changes in polarization of the input signal.
The circuit according to claim 3 wherein the substrate comprises lithium niobate.
A circuit for regulating optical power levels comprising:
- an M.times.N optical switch array, where M and N are integers;
- a plurality of parallel connected electrically controlled attenuators coupled to the switch array, each attenuator including an input for receiving an optical input signal, at least one electrode, and an output for delivering an optical output signal wherein power level of the output signal is normally dependent upon polarizations of the input signal;
- and
- feedback loops each including a photodetector optically coupled to at least a portion of the output signal from a corresponding attenuator and electrically coupled to the at least one electrode of the corresponding attenuator for controlling the power level of the output signal in response to the electrical signal from the photodetector,
- whereby the feedback loop results in power levels of the output signal being essentially independent of changes in polarization of the input signal.
Dependencies are inferred from the claim text.