The LEONI subsidiary, j-fiber, is at the forefront of developing and producing high-quality preforms using highly pure fused silica materials. These preforms are meticulously crafted according to customer specifications, serving as the foundation for manufacturing high-performance special fibers and standard fibers. Whether your objective is high data rate transmission or high-power laser applications, LEONI can tailor the waveguide design to meet your specific demands, from prototype to series production.

The preform design and configuration can be customized in terms of core profile—either step-index or graded-index—and dopant options, including Germanium, Fluorine, Boron, or Rare-earth elements, to achieve the desired numerical aperture. The process of creating these preforms involves a sophisticated step-by-step methodology. Initially, the appropriate core material is selected, either from LEONI's production of undoped fused silica with varying OH content or by directly coating doped fused silica. Subsequently, the final waveguide preform is produced using LEONI's proprietary MCVD process for both graded-index and step-index fibers or the PBVD process for large core step-index fibers.

Each preform undergoes rigorous quality monitoring to ensure it meets the specified performance parameters, resulting in preforms that deliver outstanding performance during fiber drawing for demanding applications. LEONI also offers graded-index preforms for high-performance multimode fibers in 50/125 and 62.5/125 designs. These preforms are manufactured using an innovative MCVD production technique, ensuring that the specified fiber performance properties are consistently met.

On request, these graded-index preforms can be delivered with a handle, facilitating their fixation in the drawing tower. This meticulous attention to detail and commitment to quality make LEONI's preforms an ideal choice for applications requiring precision and reliability.