Title :
Fibre core profile characterization by measuring group velocity equalization wavelengths
Author :
Archambault, J.-L. ; Black, R.J. ; Bures, J. ; Gonthier, F. ; Lacroix, S. ; Saravanos, C.
Author_Institution :
Dept. de Genie Phys., Ecole Polytech., Montreal, Que., Canada
fDate :
4/1/1991 12:00:00 AM
Abstract :
When operated at shorter wavelengths, fibers that are single mode at telecommunications wavelengths of 1.3 and 1.55 mu m become few mode. Relative values of the group velocity equalization wavelengths for the different mode pairs existing down to visible wavelengths are quite sensitive to the refractive-index profile. Their measurement by few-mode interferometry provides simple, fast, and accurate characterization of fiber core refractive-index profile parameters: numerical aperture, core radius, central dip, and dopant diffusion. The method is attractive as a complement or alternative to standard refracted-near-field and preform measurements.<>
Keywords :
light interferometry; optical fibres; optical testing; refractive index measurement; central dip; core radius; dopant diffusion; few-mode interferometry; fiber core refractive-index profile parameters; fibre core profile characterisation; fibre modes; group velocity equalization wavelengths; group velocity measurement; mode pairs; numerical aperture; refractometry; short fibre wavelength operation; visible wavelengths; Calibration; Interferometry; Measurement standards; Optical fiber cables; Optical fiber polarization; Optical fiber testing; Preforms; Process control; Velocity measurement; Wavelength measurement;
Journal_Title :
Photonics Technology Letters, IEEE
