Distribution of light density inside metal-coated micrometer-size optical tapers

We tackle the complex problem of taper beating inside an optical fiber tip used in scanning near-field optical microscopes. The technique is based on the usual ray tracing. Its interest is in the modeling, laking into account not only the power input distribution but any shape of tapers. The thermal -optical behavior of a shell-shaped taper is compared with that of a pure c onical taper. Sharp power concentration peaks inside nonlinear taper profil es have been demonstrated, in contrast with the smooth power distribution i nside cone shapes. The results present heat zones that are in agreement wit h our thermal model. (C) 2001 Society of Photo-Optical instrumentation Engi neers.