Standard Wars in Fiber Optics: The Preform Core Battle

Introduction#

In the era of AI computing, the demand for high-speed, low-latency interconnection has never been greater. Optical fiber serves as the backbone of data centers and AI clusters, where massive parallel processing requires unprecedented bandwidth and energy efficiency. As global standards bodies race to define the next generation of optical transport, a subtle but critical shift has occurred: the standards war has moved upstream to the preform core, the very heart of the fiber.

Traditionally, fiber standards focused on cable design, connector interfaces, and transmission protocols. However, with AI workloads pushing fibers to their physical limits, the core structure and material composition now determine system-level performance. This guide analyzes why the preform core has become the new battleground and offers strategic recommendations for Chinese enterprises aiming to lead.

The Shift to Preform Core Standards#

The preform is a glass cylinder from which optical fiber is drawn. Its core, doped with precise concentrations of germanium, fluorine, or other elements, dictates key optical properties such as attenuation, dispersion, and nonlinearity. In the past, these parameters were considered proprietary manufacturing details. Today, they are increasingly codified in international standards because AI interconnects demand ultra-low loss and precise modal control.

Standards bodies such as the International Telecommunication Union (ITU) and the Institute of Electrical and Electronics Engineers (IEEE) are now developing specifications that reference core design directly. For instance, multicore fiber (MCF) standards must define core-to-core spacing, crosstalk limits, and cladding diameter. These parameters originate from the preform design, not the final fiber. Consequently, companies that hold core-level patents can influence standards and gain a first-mover advantage.

The preform core also determines compatibility with silicon photonics and coherent optics. As AI clusters adopt co-packaged optics, the fiber must match the mode field diameter of photonic chips. This coupling efficiency is rooted in the preform core profile, making it a strategic control point.

Core Patents: Multicore and Ultra-Low Loss#

Multicore fiber enables spatial division multiplexing, multiplying capacity by using multiple cores within a single fiber. Key patents cover core arrangement, trench-assisted structures for low crosstalk, and methods for manufacturing multicore preforms. These patents are essential for standardizing MCF interfaces and ensuring interoperability. Companies like those in China have made significant progress, but early patent filings from established players still dominate essential IP.

Ultra-low loss fiber, with attenuation below 0.15 dB/km, relies on preform purity and dopant distribution. Patents on pure silica core, fluorine-doped cladding, and advanced dehydration processes are critical. These technologies reduce signal loss in long-haul AI data center links, where every fraction of a decibel translates into energy savings. Standards for ultra-low loss fiber often incorporate test methods that depend on core geometry, further entrenching core patents.

Moreover, patents on bend-insensitive cores are vital for dense AI racks. These cores use trench-assisted designs to confine light tightly, reducing bend losses. As standards evolve to support higher port counts, such patents become standard-essential, giving their holders leverage in licensing negotiations.

Strategic Recommendations for Chinese Enterprises#

Chinese fiber manufacturers should prioritize preform core R&D and patent portfolio building. First, invest in fundamental research on novel dopants and nanostructured cores. Collaborate with universities and research institutes to file patents early, especially in multicore and ultra-low loss domains. Second, actively participate in international standards organizations. By contributing technical proposals backed by strong patents, Chinese firms can shape standards to align with their IP.

Third, build cross-licensing alliances with global players. Since no single company holds all essential patents, pooling resources can reduce litigation risks and accelerate standardization. Fourth, develop in-house preform manufacturing capabilities to avoid dependence on foreign suppliers. Vertical integration ensures that core designs remain proprietary and can be quickly adapted to new standards.

Finally, focus on application-specific standards. AI computing has unique requirements, such as high-density interconnects and low latency. By driving standards for these niches, Chinese enterprises can create new markets where their core patents are indispensable. Government support through research grants and standardization incentives can further accelerate this strategy.

Conclusion#

The standards war in fiber optics has indeed moved to the preform core. As AI computing reshapes network demands, control over core design and related patents will determine who leads the next generation of optical infrastructure. For Chinese enterprises, the path forward requires a dual focus on breakthrough innovation and strategic standardization. By securing core patents and actively shaping international standards, they can transform from followers to leaders in the global fiber optics industry.