Relative power distribution in an infrared annular core optical fiber

Using scalar field approximation, an analytical investigation has been made of the relative distribution of power in the guiding region of an annular core optical fiber operating in the infrared region of the electromagnetic spectrum. The fiber core is assumed to be made of two concentric circles. Variation of the fractional power in the guiding region is plotted against the dimensionless core parameter. The cases of three lowest azimuthal modal indices have been described. It is found that the lower modes play a major role in the transmission of power.