Polarization-Maintaining Fiber (PMF) plays an irreplaceable role in fiber-optic communications, fiber-optic sensing (such as fiber-optic gyroscopes, fiber-optic current transformers), medical equipment, and other fields because it can maintain the polarization state of light waves715. However, its fusion splicing technology has long faced problems such as low coating stripping efficiency, insufficient axis accuracy, and high equipment costs. In recent years, with the rapid development of technologies such as 5G, the Internet of Things, and data centers, polarization-maintaining fusion splicing technology has ushered in a number of breakthrough innovations, driving the industry towards high efficiency, automation, and low cost.

I. Technical Challenges and Core Breakthroughs

Coating Stripping Difficulties

Traditional fiber fusion splicing requires the removal of the coating first, and 60um fine-diameter polarization-maintaining fiber is easy to cause low stripping efficiency or damage the fiber due to its small diameter and complex coating material.

High-precision axis alignment and automation requirements

Polarization-maintaining fiber fusion splicing requires strict alignment of the fast/slow axis (usually the deviation needs to be ≤1°), and the traditional method of relying on manual adjustment is inefficient. The S-12PM fusion splicer,made by SHINHO OPTICS, further optimizes the stability and flexibility of the fusion splicer through precise axis alignment, prism mode to achieve fusion at different angles, and 180°precise rotation. It is suitable for panda, bowtie, ellipse, dual-mode fiber observation methods, and double cat's eye alignment.

Equipment cost and compatibility issues

Traditional polarization-maintaining fusion splicers are expensive and have poor compatibility with different types of optical fibers. Early patents (such as the end-face-based axis alignment device in 2014) expanded the functions of single-mode fusion splicers by adding tooling, reducing equipment investment costs and supporting the fusion of different types of polarization-maintaining fibers15.

2. Application of innovative technologies and industry impact

Improve the transmission efficiency of optical communications

Promote the development of fiber-optic sensing technology

Fiber-optic gyroscopes and current transformers rely on high-precision splicing. The technological breakthroughs of SHINHO OPTICS have reduced splicing losses to below 0.05dB, laying the foundation for mass production of high-precision sensors.

Market structure and localization process

The global polarization-maintaining splicing equipment market has long been dominated by international manufacturers such as Fujikura and Furukawa, but the patent layout of Chinese companies (such as SHINHO OPTICS LIMITED) is gradually breaking the monopoly. Data from 2024 shows that China's polarization-maintaining splicing machine market has grown by 12%, and it is expected to account for more than 25% of the global share in 203024.

3. Future development trends

Intelligence and full automation

Combining AI image recognition and machine learning algorithms, adaptive adjustment of welding parameters can be achieved to reduce manual intervention.

Environmental protection and material innovation

The environmental performance of stripping agents and welding auxiliary materials has become a research and development focus, and it is necessary to balance high efficiency and low toxicity.

Multi-scenario adaptation and standardization

With the application of polarization-maintaining optical fiber in emerging fields such as quantum communication and laser medical treatment, welding technology needs to be compatible with more optical fiber types (such as panda type and bow tie type) and promote the unification of industry standards715.

Conclusion

The progress of polarization-maintaining welding technology is not only a microcosm of the development of the optical fiber industry, but also a reflection of the transition of Chinese technology companies from "following" to "running side by side". In the future, with the popularization of automated equipment and the acceleration of domestic substitution, polarization-maintaining welding will promote the comprehensive upgrading of optical communications, high-end manufacturing and other fields, and inject new momentum into the global digitalization process.