A method and system for determining the orientation of an optical device,
the optical device having data carrier means for carrying data related to
the optical device, the data carrier having data carrier means operable
in at least one of an electrical mode and a magnetic mode; the data
carrier means being associated with an optical device by at least at
least one of the group of depositing on or printing on a posterior
surface or anterior surface of the optical device, including the data
carrier with the optical device material, wherein data carrier means
emits a data signal periodically or in response to a external signal from
an external means.