Particle-modified polymeric cladding on glass optical fibers enhances radial light scattering

Radially light-emitting optical fibers are of increasing interest for applications in medicine, visible aesthetics, and environmental remediation. Optical fibers contain a light guiding core coated by protective polymer layers (cladding and coating), which assure both the strength and flexibility of the optical fiber. This paper examines the feasibility of scattering light radially from fibers by loading the fiber cladding with particle scattering centers during the optical fiber fabrication process. This work uses an in-line full-scale scalable facility to coat the fibers and control the polymer cladding and silica sphere. Loadings up to 2.0 % wt. of 500-nm silica particles on the cladding of the optical fiber led to an average of 80 times higher scattering for visible light and up to 30 times higher in the UVA wavelength range compared against cladding without particle modifications. This study illustrated feasibility of fabricating broad-band light scattering optical fibers for use with modified polymeric cladding.