Abstract: A fiber optic array and method of making same has precision fiducial marks that aid in the alignment of the fiber optic array. The invention requires forming additional optical features adjacent to the fiber optic array that is used to write fiducial marks on an opposite surface in the medium containing the fiber optic array. Fiducial marks are formed when a high intensity collimated beam of light is directed through the optical features onto a treated portion of the transparent medium. Fiducial accuracies of 1 micron are possible by using this approach.