Polarized wave non dependence type optical pulse separated circuit and polarized wave non dependence type optical pulse multiplex circuit

摘要

PURPOSE: To provide the optical pulse branching circuit which does not depend upon the polarization state of input signal light and is a fully optical type, safe, and extremely fast for an optical fiber communication system wherein it is difficult to stabilize the polarization state by setting the polarization state of control light so that the light has the same intensity on orthogonal main axes of an optical Kerr medium. ;CONSTITUTION: A birefringence compensation type polarization holding optical fiber which is connected having its main axis direction rotated by 90° at the intermediate point between output ports 22 and 23 of an optical coupler 19, is used as the optical Kerr medium 24 which controls the output ports 22 and 23 of the optical coupler 19. Then, the control light which has the polarization state wherein the intensity is equal on its (x) and (y) axes is used; and input signal light A is inputted to the input port 12 of an optical circulator 11 and branched output signals B and C are outputted from the output port 14 of the optical circulator 11 and the output port 27 of an optical branching filter 25. Consequently, a phase can equally be induced for the signal light in an optional polarization state and the input signal light polarization dependency of switching can be eliminated.;COPYRIGHT: (C)1994,JPO&Japio