Effect of Helix Pitch Angle on the Modal Dispersion Characteristic of Step-Index Optical Fiber

Ashish Kumar Mishra, Deepak Kumar, Onkar Nanth Singh

Department of Applied Physics Institute of Technology Banaras Hindu University, Varanasi, India.
Faculty of Engineering Multimedia University Cyberjaya,Malaysia.

DOI: 10.4236/jemaa.2012.47038                

Abstract

The general characteristic equation is derived for the helically cladded step-index optical fiber. The dispersion curves are drawn for the different pitch angles Ψ and mode order ν = 1. The effect of helix pitch angle on the dispersion characteristics and also on the modal cut-off condition is examined. Except for the lowest order mode, all the modes appear in pairs. The lowest order mode displays the negative dispersion for the some value of normalized frequency V and depends on the helix pitch angle Ψ.

Keywords

Modal Dispersion; Pitch Angle; Modal Cut-off

Conflicts of Interest

The authors declare no conflicts of interest.

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