Abstract

Fiber-optic polarization-tunable filters, depolarizers, binary polarization switches/modulators, polarization-division multiplexers, and many other polarization-related fiber-optic components require fiber-optic variable-polarization beam splitteres and combines (VPBSs and VPBCs). Splitting ratios cannot be selected for polarization-maintaining (PM) fiber couplers fabricated by thermal fusion. A mechanically tunable PM fiber coupler employing two polished PM fibers suffers from fabrication complexity, tuning difficulties and a poor extinction ratio. An integrated-optic polarization beam splitter using an LiNbO₃ or III-V semiconductor substrate also posseses the shortcomings of high insertion loss, poor polarization extinction ratio, and limited operational spectral bandwidth.

© 1995 Optical Society of America