How optical surface inhomogeneities of the input end of a lightguide affect the excited modal composition of radiation

摘要

The influence of optical inhomogeneities at the end of a fiber lightguide on the modal composition of the propagating radiation is analyzed. Estimates are obtained for describing the resulting effects, and the modal composition in a short section of a lightguide with various heights of the surface roughness of the input end is experimentally studied. A technique is proposed for using light-scattering lacquer to standardize the measurements of the lightguide parameters. (C) 2015 Optical Society of America.