Light scattering from elliptical fibers.
The ellipticity of the cross section of an unclad fiber can be obtained by observing the pattern of backscattered laser light that is incident at right angles to the fiber axis. The backscattered band of light has a definite width that depends on the ellipticity and relative orientation of the fiber. By observing the width and the shift of the band of backscattered light as a function of fiber orientation the ellipticity of the fiber cross section can be determined with the help of plots given in this paper.
Marcuse
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