| 摘要 |
PURPOSE:To allow adjustment of film thicknesses and easier production by stretching a laminate formed by alternate lamination of two kinds of dielectric layers which are different in refractive index from each other plural times in the direction perpendicular to the lamination direction. CONSTITUTION:A base material 8 having the multilayered dielectric structure obtd. by working dielectric materials 6 and 7 which are different in the refractive index from each other to a prescribed thickness and superposing these materials is inserted into a glass pipe 9 and glass rods 10 of the same quality as the quality of a pipe 9 are inserted and packed into the gap between the base material 8 and the pipe 9 to obtain the optical fiber base material 11 having the structure in which the gap is filled. The prescribed multilayered dielectric structure of this optical fiber is obtd. by assembling the multilayered dielectric structure in the stage of the large-sized base material, then drawing this structure. Since the optical fiber is formed by drawing, a large quantity of the multilayered dielectric structures which are uniform in the longitudinal direction can be produced at one time. The adjustment of the layer thickness and the mass production are thereby facilitated. |
