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Are the Formulas for Mode-Field Diameter Correct?



Ronald C. Wittmann, M. Young


We have found conceptual problems with the far-field formula1 for mode field diameter First, the formulation is incomplete in that it ignores the obliquity factor; second, it assumes that the field at the end of a truncated fiber is identical to the mode field of the fiber. When both these factors are taken into account, the resulting integrals fail to converge. We suggest that the original far-field formula be taken as the definition of mode-field diameter and derive an alternate near-field formula.
Proceedings Title
Tech. Dig., Symp. on Optical Fiber Meas.
Conference Dates
September 15-17, 1998
Conference Location
Boulder, CO


diffraction, far-field scan, fiber optics, mode-field scan, obliquity factor, optical communications, optical fibers


Wittmann, R. and Young, M. (1998), Are the Formulas for Mode-Field Diameter Correct?, Tech. Dig., Symp. on Optical Fiber Meas., Boulder, CO (Accessed June 20, 2024)


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Created August 31, 1998, Updated October 12, 2021