Light diffusing optical fibers for emitting white light

A light diffusing optical fiber comprising:

• a glass core;
• a cladding surrounding the glass core;
• a phosphor layer surrounding the cladding;
• and
• a plurality of scattering structures positioned within the glass core, the cladding, or both the glass core and the cladding, wherein:
• the plurality of scattering structures are configured to scatter guided light toward the phosphor layer of the light diffusing optical fiber such that a portion of the guided light diffuses through the phosphor layer along a diffusion length of the light diffusing optical fiber, and
• the phosphor layer comprises two or more phosphors and is configured to convert guided light diffusing through the phosphor layer into emission light such that the color of the emission light comprises a chromaticity within an x-y chromaticity region on a CIE 1931 chromaticity space defined by:
• a first x-y boundary line that extends from a first x-y chromaticity point located between about (0.15, 0.0) and (0.25, 0.0) and a second x-y chromaticity point located at about (0.4, 0.6);
• and
• a second x-y boundary line that extends from the first x-y chromaticity point and a third x-y chromaticity point located at about (0.6, 0.4);
• wherein a scattering material is disposed within the phosphor layer, and wherein the phosphor layer comprises a buffer tube.

A light diffusing optical fiber comprising:

• a first end, a second end opposing the first end,
• a length between the first end and the second end,
• a glass core extending along the length;
• and
• a cladding surrounding at least a portion of the glass core;
• a polymer layer surrounding the cladding;
• and
• wherein the fiber is configured to scatter a guided light propagating along the light diffusing optical fiber toward an outer surface of the light diffusing optical fiber such that a portion of the guided light diffuses through the polymer layer along a diffusion length of the light diffusing optical fiber;
• wherein, after the light diffusing fiber is aged by placing the fiber in a chamber having a temperature of 85° C. and 85% relative humidity for 100 hours, and after a light source is optically coupled to the first end, the light diffusing fiber exhibits any one of:
• an optical loss that changes about 20% or less,
• a scattering efficiency in a spectral range from 420 nm to 800 nm that changes about 10% or less, and
• a brightness at any given portion of the fiber along the length that changes less than 25%;
• wherein the polymer layer comprises two or more phosphors;
• and
• wherein the polymer layer comprises a buffer tube.