  We consider how vectorial aspects (polarization) of light propagation can be
implemented, and its origin, within a Feynman path integral approach. A key
part of this scheme is in generalising the standard optical path length
integral from a scalar to a matrix quantity. Reparametrization invariance along
the rays allows a covariant formulation where propagation can take place along
a general curve. A general gradient index background is used to demonstrate the
scheme. This affords a description of classical imaging optics when the
polarization aspects may be varying rapidly and cannot be neglected.
