Multimode optical fibers are expected to comprise 15% of the world optical fiber market by the year 2000. The large cores of these fibers permit them to be used with inexpensive light sources, and they are best suited for applications in Local Area Networks. At the present time, there are no suitable fabrication techniques to make large graded index preforms. The investigator will research the possibility of using organic precursors containing Si (but with no Cl) that react with oxygen to produce large amounts of silicon dioxide. The reacted silicon dioxide will impinge on a rotating rod and an unsintered cylinder of the silicon dioxide will be formed. During the deposition, the silicon dioxide will be doped with a glass modifier that will raise the index of refraction. This will be done with computer control to ensure a smooth gradation of the refractive index, and thus, high bandwidth functionality. This preform is then sintered to produce a vitreous, pore free preform with graded index. It is believed that this process is environmentally friendly (no chlorine), and that the large preforms will significantly reduce the manufacturing costs of high bandwidth multimode optical fibers.
