Wang Ruichun's Team Achieves Industrialization of Large-Size Fiber Preforms After 10 Years, Building World's

Optical fiber preforms, the core raw material for producing optical fibers, resemble transparent glass rods. Wang Ruichun's work focuses on efficiently preparing large-size preforms and drawing them into hair-thin glass filaments. A preform is not merely made of quartz glass; it encodes the entire set of technical parameters, from material formulation to process conditions. Its preparation is the most difficult and technically challenging step in fiber manufacturing, demanding extremely high standards in material purity, process control, equipment precision, and system integration.

As the Digital China initiative accelerates, communication networks are evolving from gigabit to terabit speeds, requiring fibers to transmit more signals over longer distances while reducing loss to theoretical limits. Large-size preforms can significantly boost fiber manufacturing efficiency, but larger preforms impose exponentially higher requirements on refractive index uniformity, impurity control, and geometric precision, and they are more prone to cracking. In the early stages, high-end preforms and quartz tubes were entirely imported, with core processes and production equipment controlled by foreign suppliers.

In 2011, Wang Ruichun's team began independent development of large-size optical fiber preforms based on VAD (vapor-phase axial deposition) and OVD (outside vapor-phase deposition) processes. Starting from scratch, the team took on the challenge of global-leading technology, assembling a multidisciplinary R&D group of over 100 engineers specializing in mechanics, electrical engineering, materials, simulation, and optics. After hundreds or thousands of failed attempts, they progressively solved industry-wide challenges such as precise refractive index profile control, low deposition efficiency, cracking susceptibility, uniform sintering temperature field control, deep purification, and precise doping. They developed a novel preparation route using self-developed VAD for large-size core rods and OVD for cladding.

Transitioning from laboratory results to factory-scale production required solving industrialization issues. The team continuously iterated on deposition, sintering, and splicing core technologies at the Qianjiang base, optimizing furnace temperature adaptive control and precision optical inspection systems to address uniformity and stress control in large-size preforms. They implemented phased capacity expansions and intelligent production line upgrades, establishing an efficient drawing process. Leveraging the local salt-chemical industry advantages in Qianjiang, they recycled hydrogen and other raw materials to reduce manufacturing costs, while conducting process validation and stability tests to facilitate the transfer of technology to mass production.

Over ten years, the team overcame key technical challenges in manufacturing large-size optical fiber preforms and high-purity synthetic quartz tubes using self-developed VAD/OVD core processes and complete equipment sets, gradually achieving domestic substitution of manufacturing equipment. The resulting products reached internationally leading levels in technical specifications and yield, and the team built the world's largest single-site R&D and manufacturing base for optical fiber preforms. In July 2026, the team-led project, "Key Technologies and Applications for Preparing Quartz Fiber Core Materials," won a second-class prize in the 2025 National Science and Technology Progress Awards, marking the fourth time the company has led a project to receive this honor. Looking ahead, the team will continue focusing on developing new types of optical fibers, improving transmission performance, and advancing a self-owned intellectual property system for optical fiber preform core technologies.