Polarization-dependent retroreflection mirror device

A deinterleaver apparatus comprising:

• a first port for inputting a first polarized optical signal, which comprises a second optical signal with a first subset of channels and a third optical signal with a second subset of channels;
• a second port for outputting the second optical signal;
• a third port for outputting the third optical signal;
• a birefringent assembly optically coupled to the first, second and third ports, whereby, after the first optical signal makes a first pass through the birefringent assembly along a first path, the second optical signal exits the birefringent assembly with a polarization orthogonal to the polarization of the third optical signal;
• beam-directing means including a first wedge having a first optical axis, and a second wedge having a second optical axis that is perpendicular to the first optical axis, the beam directing means for receiving the first optical signal along the first path, and for directing the second and third optical signals outwardly therefrom with a launch angle therebetween;
• polarization rotating means for effectively rotating the polarization of the second and third optical signals by 90°;
• and
• a reflector for directing the second and third optical signals back through the beam-directing means;
• whereby, after passing through the beam-directing means a second time, the second and third optical signals:
• exit the beam-directing means along second and third paths, respectively, which are substantially parallel to the first path;
• pass through the birefringent assembly for a second time;
• and exit via the second and third ports, respectively.

An interleaver apparatus comprising:

• a first port for outputting a first polarized optical signal, which comprises a second optical signal with a first subset of channels and a third optical signal with a second subset of channels;
• a second port for inputting the second optical signal;
• a third port for inputting the third optical signal;
• a birefringent assembly optically coupled to the first, second and third ports, whereby, after the second and third optical signals make a first pass through the birefringent assembly along second and third paths, the second optical signal exits the birefringent assembly with a polarization orthogonal to the polarization of the third optical signal;
• beam-directing means including a first wedge having a first optical axis, and a second wedge having a second optical axis that is perpendicular to the first optical axis, the beam directing means for receiving the second and third optical signals along the second and third paths, respectively, for directing the second optical signal outwardly therefrom at a first angle from a first launch axis, and for directing the third optical signal outwardly therefrom at a second angle from a second launch axis, the first and second launch axes being parallel to the second and third paths;
• polarization rotating means for effectively rotating the polarization of the second and third optical signals by 90°;
• and
• a reflector for directing the second and third optical signals back through the beam-directing means;
• whereby, after passing through the beam-directing means a second time, the second and third optical signals:
• exit the beam-directing means together along a first path, which is substantially parallel to the second and third paths;
• pass through the birefringent assembly for a second time;
• and exit via the first port.