Patent ID: 6795626
Filing Date: 2004-09-21
Classification: G02F

Abstract:
An optical threshold device comprising:an optical loop having first and second terminals and comprising at least one non-linear optical element and at least one optical attenuator; and an optical coupler able to couple a first portion of an input signal to said first terminal and a second portion of the input signal to said second terminal, wherein said optical loop is able to produce a first return signal at said second terminal and a second return signal at said first terminal, wherein said optical coupler is able to combine the first and second return signals into an output signal, and wherein said at least one non-linear optical element and said at least one optical attenuator are positioned on said optical loop such that said non-linear optical element is able to receive said first input portion prior to its attenuation by said at least one optical attenuator and to receive said second input portion after its attenuation by said at least one optical attenuator.