What does special optical fiber refer to?

　　Special optical fiber refers to an optical fiber designed and manufactured to achieve a special function at a specific wavelength. It is a type of optical fiber, but it is quite different from conventional communication optical fibers in terms of doping elements, working wavelength, structure and optical properties. The following is a detailed explanation of special optical fibers:

　　I. Definition and Classification

　　Definition: Special optical fibers are optical fibers with special properties, usually based on ordinary optical fibers, by changing the material composition, structural shape, etc., to achieve special properties, such as high temperature stability, bending resistance, radiation resistance, etc.

　　Category:

　　Polarization-maintaining single-mode fiber: allows linearly polarized light input to the fiber to be transmitted independently and stably in the fiber.

　　Large core diameter and large numerical aperture fiber: The core diameter and numerical aperture are larger than the nominal value, and can be used in systems with special requirements.

　　Double-clad fiber: with a special double-layer structure, it is suitable for the transmission of high-power lasers.

　　Triangular-core fiber: with a special triangular-core structure, it is used to achieve specific optical properties.

　　Optical fiber bundles are made up of tens to hundreds of thousands of naked fibers with cores and cladding layers, which are used to transmit images.

　　Second, the application field

　　Laser field: Special optical fibers are increasingly used in the field of lasers, and can be used in the output of high-power lasers, laser sensors, laser printing, laser manufacturing, and other fields.

　　Communication field: The application of special optical fibers in the communication field is mainly reflected in optical fiber sensing, optical fiber extenders, etc. For example, by measuring the temperature, pressure, displacement and other parameters in the optical fiber, real-time monitoring of industrial processes and environmental conditions is realized; by extending the signal transmission distance, remote communication is realized.

　　Sensing field: The application of special optical fibers in the sensing field is also increasing, and can be used in the sensing fields of temperature, pressure, vibration, deformation, electromagnetic field, etc. For example, optical fiber sensing technology based on Brillouin scattering principle can realize the measurement of physical parameters such as strain and tension, and is widely used in industrial, aviation, aerospace, medical and other fields.

　　III. Development trends

　　High value-added and high-tech content: With the development of modern technology, the performance requirements for special optical fibers are getting higher and higher, which has promoted the development and production of high-value-added and high-tech special optical fibers.

　　Optical fiber communication devices: The development and application of optical fiber communication devices such as adjustable dispersion compensator, dynamic PMD compensator, high power amplifier, and optical parametric amplifier OPA have further promoted the development of special optical fibers in the communication field.

　　Energy fiber devices: The development and application of high-power active fiber devices such as all-fiber lasers, single-frequency, narrow linewidth, and passive fiber devices provide more possibilities for the application of special fibers in the laser field.

　　Sensing fiber optic devices: Sensing fiber optic devices for a variety of special environmental applications, such as pressure, temperature, displacement and other parameters of sensing and detector devices, fiber optic gyroscopes, etc., provide a broad market space for the application of special fiber optics in the sensing field.

　　In summary, as a high-performance optical material, special optical fibers have broad application prospects and development space in the fields of lasers, communications, sensing, etc. With the continuous development of modern science and technology, the performance of special optical fibers will continue to improve, and the application field will continue to expand.