A METHOD OF PRODUCING AN OPTICAL WAVEGUIDE BY FIRST FORMING A FILM OF GLASS WITH A PRESELECTED INDEX OF REFRACTION ON THE INSIDE WALL OF A GLASS TUBE HAVING A DIFFERENT PRESELECTED INDEX OF REFRACTION. THIS GLASS TUBE AND GLASS FILM COMBINATION IS THEN DRAWN TO REDUCE THE CROSS-SECTIONAL AREA AND TO COLLAPSE THE FILM OF GLASS TO FORM A FIBER HAVING A SOLID CROSS-SECTIONAL AREA; THE CORE BEING FORMED FROM THE GLASS FILM, AND THE CLADDING BEING FORMED FROM THE GLASS TUBE.