Cylindrical polarization diversity asembly

A method of providing two spatially separated orthogonally polarized beams of light, comprising the steps of:

• launching an input beam into and through an optical element having optical power that will provide an output beam having an eccentric cross-section;
• and
• launching the output beam into a birefringent crystal to obtain two orthogonally polarized spatially non-overlapping sub-beams.

A polarization diversity circuit comprising:

• a cylindrical optical element for receiving an input beam of light and for providing an output beam having a substantially elliptical cross-section, said elliptical cross-section having a major axis and a minor axis, said output beam being substantially collimated in a direction of the minor axis and substantially diverging in a direction of the major axis;
• and
• a birefringent element for receiving the output beam from the cylindrical optical element and for separating the output beam into two sub-beams having substantially orthogonal polarization states and having substantially elliptical cross-sections, said sub-beams being substantially collimated in the direction of the minor axis and substantially diverging in the direction of the major axis, and wherein the birefringent element is arranged to cause a displacement of one of the sub-beams in the direction of the minor axis.