Investment Rating - The investment rating for the industry is "Positive" (maintained) [3] Core Viewpoints - The demand for AI computing power is driving the optical fiber industry into an upward cycle, with prices for G.652.D bare optical fibers rising from less than 20 yuan per core kilometer and accelerating in 2026 due to a reversal in supply and demand dynamics [3][8] - The optical fiber industry is cyclical, closely linked to investments in the telecommunications sector, with each iteration of communication technology (3G, 4G, 5G) leading to increased demand for optical fibers [4][8] - The primary new demand is coming from the construction of AI data centers, leading to a global shortage of optical fibers, particularly as North American data center markets have surpassed telecommunications markets in size [4][20] Summary by Sections Section 1: Industry Performance - The optical fiber market has seen a moderate price increase over the past six months, with a significant acceleration in 2026 due to supply-side capacity clearing and increased demand from AI data center construction [3][4] Section 2: Market Concentration - The optical fiber market is highly concentrated, with the top four manufacturers (Corning, Yangtze Optical, Zhongtian Technology, and Hengtong Optic-Electric) holding over 50% market share, and the top ten companies exceeding 90% [4][11] Section 3: Supply Chain Constraints - The production of optical fiber preform, a critical material, faces rigid bottlenecks with an expansion cycle of about two years, leading to a mismatch between supply and demand in the optical fiber cable market [5][20] Section 4: Investment Recommendations - The outlook for the optical fiber and cable industry is positive, with expectations for improved performance of related companies as optical fiber prices rise. Key recommendations include Zhongtian Technology, with additional attention to Yangtze Optical, Hengtong Optic-Electric, and Longfly Fiber [5][20]