Binary silica optical fibers: refractive index and profile dispersion measurements

The variation of the core-cladding refractive index difference Deltan(lambda) is determined as a function of wavelength for GeO(2)-SiO(2), B(2)O(3)-SiO(2), TiO(2)-SiO(2), P(2)O(5)-SiO(2), Al(2)O(3)-SiO(2), and Cs(2)O-SiO(2) optical fibers. The measurements are obtained by electronically processing the output of an interference microscope illuminated by a monochromatic light source variable over the 0.5-1.1-microm range. The Deltan(lambda) results are utilized to calculate the precise grading of the refractive index profile characterized by an exponent alpha(lambda) required to achieve a minimum modal dispersion. The material dispersion for these compositions is also calculated with the aid of available n(lambda) data for SiO(2).