Fused silica step-index fibers tailored for applications from UV to IR wavelength range

Optical fibers made of fused silica have many applications like telecom, industrial, medical, or spectroscopy. These applications are as varied as are the requirements for the fibers. Large core step index multimode fibers made of high purity fused silica core and fluorine doped silica cladding are common standard in industrial high-power laser, minimal invasive medical and spectroscopic applications. One of the biggest factors influencing fiber performance is the utilized fused silica core material and its composition. Hydroxyl groups and trace impurities, for example, can influence the transmission properties of the fiber. But also, defect centers created by strong UV radiation or drawing induced absorption bands define the performance over time. Therefore, the choice of the right material is key for high performing fibers. In addition, the height of the refractive index step between the core and the cladding, which defines the numerical aperture, as well as the cladding thickness and cross section design of the fiber are important factors which should be balanced against performance and costs. Depending on the application wavelengths and performance requirements, different fused silica materials and fiber designs are recommended tailored to the application. We will present deeper insights in the optical properties of different fused silica materials and new silica material developments dedicated for the increasing utilization of blue and green lasers to give a guideline to choose the best fiber type depending on the application wavelengths.