Change in Refractive Index of a Borosilicate Glass Fiber Annealed below the Glass Transformation Temperature
Glass fibers pulled from multihole bushings can have a slight difference in thermal history that causes a distribution in the refractive index that can be narrowed by annealing the fibers. The kinetics for the initial stage change in refractive index for fiber annealed between 300° and 500°C are best described by a second-order reaction with an activation energy of 120 ± 17 kJ/mol. The improved uniformity in refractive index for annealed fibers is indicated by a decrease in the half-height width of the optical transmission versus temperature curve for glass fiber immersed in a liquid. The standard deviation in the refractive index of glass fibers with a bimodal distribution in diameter decreases from 8 x 10-4 ± 0.0002 to 4 x 10-4 ± 0.0002 after the fibers are annealed at 400°C for 1 h.
S. Kang et al., "Change in Refractive Index of a Borosilicate Glass Fiber Annealed below the Glass Transformation Temperature," Journal of the American Ceramic Society, vol. 79, no. 10, pp. 2633-2636, Wiley-Blackwell, Oct 1996.
The definitive version is available at https://doi.org/10.1111/j.1151-2916.1996.tb09026.x
Materials Science and Engineering
Keywords and Phrases
Activation energy; Annealing; Borosilicate glass; Glass transition; Light transmission; Reaction kinetics; Refractive index; Thermal effects; Bimodal distribution; Multihole bushings; Temperature curve; Glass fibers
International Standard Serial Number (ISSN)
Article - Journal
© 1996 Wiley-Blackwell, All rights reserved.