Fabrication of a graded-index polymer optical fiber preform without a cavity by inclusion of an additional monomer under a centrifugal force field.
When two or more monomers with different densities and refractive indices are polymerized under a centrifugal force field, a radially varying refractive index is generated owing to the difference in density of the monomers. After the polymerization is completed, a cavity is generated about the rotational axis as a result of inherent volume shrinkage during bulk radical polymerization. Therefore it is necessary to feed an additional monomer into the cavity to compensate for the undesirable volume shrinkage. We have successfully fabricated a preform with graded indices for polymer optical fiber without a cavity by adding another monomer during rotation of the reactor. One can control the overall refractive-index profile by changing the rotation speed. Furthermore, the refractive-index profile can be predicted as a function of rotating speed by use of a simple mathematical model.
Im
Sang Hyuk
SH
Center for Advanced Functional Polymers, Department of Chemical Engineering, Korea Advanced Institute of Science and Technology, Taejon.
Suh
Duck Jong
DJ
Park
O Ok
OO
Cho
Hansol
H
Choi
Jin Sung
JS
Park
Jae Keun
JK
Hwang
Jin Taek
JT