In fiber optics, a cladding mode is a mode that is confined to the cladding of an optical fiber by virtue of the fact that the cladding has a higher refractive index than the surrounding medium, which is either air or the primary polymer overcoat. These modes are generally undesired.
Modern fibers have a primary polymer overcoat with a refractive index that is slightly higher than that of the cladding, so that light propagating in the cladding is rapidly attenuated and disappears after only a few centimeters of propagation. An exception to this is double-clad fiber, which is designed to support a mode in its inner cladding, as well as one in its core.
This article incorporates public domain material from the General Services Administration document "Federal Standard 1037C".
Famous quotes containing the word mode:
“The character of the logger’s admiration is betrayed by his very mode of expressing it.... He admires the log, the carcass or corpse, more than the tree.... What right have you to celebrate the virtues of the man you murdered?”
—Henry David Thoreau (1817–1862)