Patent ID: 8131120

Claim:
An apparatus, comprising: a planar optical structure, including: an input coupler on a planar substrate, said input coupler configured to divide an incoming light into two light beams; first and second planar waveguides on said planar substrate, each of said first and second waveguides being configured to receive one of said two light beams, wherein said first waveguide has a single layer first core with a width that is greater than a width of a single layer second core of said second waveguide, and, at least one of said first or second planar waveguides is birefringent; and an output coupler on said planar substrate, said output coupler configured to receive said light beams after passage through said first and second waveguides, wherein a first output light beam from said output coupler is substantially transverse electric polarized light and a second output light beam from said output coupler is substantially transverse magnetic polarized light, wherein said first and second cores have vertical thicknesses that are less than said first core width and said second core width.