Special optical fiber and its classification

In a narrow sense, special optical fiber is a special-purpose optical fiber that is different from the special performance and application of international telecommunication standard optical fiber. Its material doping, structural design, technology, transmission wavelength, optical performance, mechanical and environmental performance all have particularity. In different industry areas. Broadly speaking, special optical fibers and even components including special optical fibers and communication optical fibers belong to the category of special optical fibers (products) and are used in various fields such as communications, sensing, electric power, petroleum and petrochemical, industrial and military.

According to different application environments, special optical fibers can be classified as follows:

Communication/device application areas: polarization-maintaining fibers for communication and communication devices, dispersion compensation fibers for dispersion management of communication transmission networks, erbium-doped and erbium-doped active fibers for communication signal amplification and fiber lasers, and passive Coupling optical fibers and bending resistant optical fibers for optical devices;

Military applications: FOG polarization-maintaining fiber for fiber-optic gyros for core aerospace components, high-temperature resistant fiber for high temperature and high pressure, etc., high-temperature resistant fiber/bending resistant fiber, anti-radiation fiber/UV fiber, and radiation resistance for fiber retarders Optical fiber; In addition, there are high-power laser transmission optical fiber and fiber optic cable for laser radar, and supercontinuum photonic crystal fiber.

Power applications: Plastic clad and glass-clad large core fiber, power cable and control components for converter valves and wind power systems, as well as fiber-optic current transformers for the monitoring of UHV currents.

Medical applications: Special numerical apertures and end-point light guide beams for laser imaging, Special medical large core fiber optics for laser surgery, various types of neon lasers and green lasers, and sensor optics for medical sensing Products, such specialty fibers need to meet relevant medical certifications.

Energy/Railway applications: high-temperature fiber optics and fiber optic cables for petroleum and petrochemical applications, vibration-sensing fiber optic cables for long-distance oil pipelines, large-core energy-conducting optical fibers for rail transit locomotives, and health monitoring of track structures Fiber optic cable.

China's optical fiber and cable manufacturers have only formed a small number of domestically produced industrial chain in the production of special optical fiber. Longfei, as the world's leading manufacturer of preforms, optical fibers and fiber optic cables, has been intensively engaged in special optical fiber for many years, and has core prefabrication such as PCVD and MCVD. Bar production process and platform, after years of technical precipitation, driven by the market, Changfei has achieved a full series of special optical fiber, has a complete special optical fiber preform and related raw materials - a full range of specialty optical fiber - special optical fiber components and systems Module industry chain structure, the industrial chain has a core domestic scale.

At present, there are two deep alliances in the international market competition structure. They basically have full series of special optical fiber products and have stable advantages in domestic and foreign related markets, namely Corning and Fujikura Union, OFS and Furukawa Union; in addition, there are also A group of specialty fiber manufacturers with proprietary technologies and their own markets, such as Nufern, LEONI, Fibercore, J-Fiber, Fiberguide and others.