A spiral wound fiber that includes birefringent interfaces is useful in
different optical devices. One type of wound fiber includes at least
first and second material layers. At least one of the layers is polymeric
and at least one of the layers is birefringent. The spiral wound fiber
may be used alone, or in an optical device. Such an optical device can
include the fiber embedded within a matrix or attached to a substrate.
The spiral wound fiber can be made by rolling a stack of at least two
layers, by coextruding the two layers or by coating a rotating form.