Application segmentation drives the bulk of the Pure Silica Core Fiber market, accounting for roughly 70 % of total revenue. Telecommunications remains the dominant sub‑segment, leveraging low‑attenuation fibers for long‑haul and submarine links; its high capital intensity and global rollout of 5G networks contribute an estimated 40 % share of the market. Data Centers follow, where ultra‑low latency and high bandwidth are critical for intra‑rack and inter‑rack connectivity, representing about 15 % of sales. Defense applications, including secure communication and high‑performance sensing, add a 7 % contribution, driven by government procurement cycles and stringent performance specifications. Medical Imaging (e.g., endoscopy, OCT) and Industrial Sensing (e.g., oil‑field monitoring) together comprise the remaining 8 %, reflecting niche but high‑margin uses. Collectively, these application categories define the Pure Silica Core Fiber segmentation landscape, with each sub‑segment’s growth rate and pricing power shaping overall market size.