MANUFACTURE OF OPTICAL FIBER

摘要

PURPOSE: To make it possible to increase the length of a fiber obtainable from a preform and to inexpensively obtain the low-loss fiber by forming the main body of a bar-shaped silica base, coating this main body with the glass of the silica base and providing the man body with an external clad. CONSTITUTION: The main body of the bar-shaped silica base having a inside part of a diameter D provided with a first clad region 11 which encloses a core region in contact therewith and has the refractive index n1 smaller than the refractive index n0 of the pure glass silica and a second clad region 12 which has an outside diameter D', has such a refractive index n2 as n2 =n0 . The low-loss optical fiber is inexpensively obtd. in such a manner.