Title :
Origin of spurious modes in the analysis of optical fibre using the finite-element or finite-difference technique
Author_Institution :
National Taiwan University, Department of Electrical Engineering, Taipei, Republic of China
Abstract :
An origin of spurious modes in the finite-element or finite-difference analysis of optical fibres is found. Such spurious modes are due to the ill-condition in the resultant matrix equation, which occurs whenever the propagation constant approaches the average between the permittivities of two consecutive node points employed.
Keywords :
difference equations; finite element analysis; optical fibres; optical waveguide theory; finite-difference technique; finite-element analysis; ill condition; matrix equation; node points; optical fibre; propagation constant; spurious modes;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19850606
