Patent ID: 7242517
Filing Date: 2007-07-10
Classification: G02F

Abstract:
1. A bidirectional isolating device comprising at least a first non-reciprocal optical assembly, said assembly comprising: at least a first polarizer; at least a first non-reciprocal polarization rotator arranged for rotating a polarization of a signal of substantially 45°±k·90°, wherein k is a non-negative integer; and at least a first wavelength selective reciprocal polarization rotator having a half-wave retarder behavior for a first group of optical frequencies and a full-wave retarder behavior for a second group of optical frequencies, according to a substantially frequency periodic transfer function; said first wavelength selective reciprocal polarization rotator comprising a predetermined number of at least five birefringent elements having a predetermined thickness and orientation, so as to obtain a transition between the half-wave retarder behavior and the full-wave retarder behavior in a frequency range lower than or equal to 40% of the period of said transfer function.