Abstract

With the increasing interest in polarization sensitive lightwave devices and systems, it has become important to efficiently couple from single-mode injection lasers into polarization-maintaining fibers. In the past, light has been coupled into polarization preserving fibers using either bulk optics or butt-coupling¹ with coupling efficiencies near 10–15%. To our knowledge, no efficient coupling method such as a microlens coupling^2,3 has been reported. Most polarization-maintaining fibers use highly doped stress regions to produce the required modal birefringence and they tend to have a greater variety of doped regions than standard fiber⁴. This makes it impossible to obtain the required uniform etching for making microlenses^2,3.

© 1985 Optical Society of America