Multi-core Fibers are designed with multiple cores within the same fiber cladding structure, and each core is equivalent to an independent transmission unit. Within the same fiber, multiple signals are transmitted independently along different cores. With the development of the information society, the demand for data transmission is increasing, and traditional single-mode optical fiber can no longer meet the growing demand for data transmission. Therefore, multi-core optical fiber emerged as the times require, which can integrate multiple cores in the same optical fiber, thereby greatly improving the data transmission capacity of the optical fiber.

The working principle of multi-core optical fiber is mainly based on the principle of total reflection of light. Each fiber core can transmit data independently, and the light between the fiber cores does not interfere with each other. This is because each fiber core is surrounded by a cladding with a high refractive index. When light is emitted from the fiber core to the cladding, as long as the incident angle is greater than the critical angle of total reflection, the light will be reflected inside the fiber core, thereby achieving light reflection. guide. Therefore, each fiber core can be used as an independent channel for data transmission.

Important parameters of multi-core fiber mainly include the number of cores, core diameter, core spacing, insertion loss, return loss, dispersion, etc. Among them, the number of cores directly determines the data transmission capability of multi-core optical fiber; the core diameter and core spacing affect the mode field distribution and mode coupling of the optical fiber; the insertion loss and return loss reflect the transmission efficiency of the optical fiber; dispersion affects the Fiber bandwidth.

Multi-core optical fiber is widely used in long-distance communications, data centers, optical fiber sensing, medical equipment and other fields. In long-distance communications, multi-core optical fiber can provide higher data transmission capabilities; in data centers, multi-core optical fiber can achieve high-density optical fiber interconnection; in optical fiber sensing, multi-core optical fiber can achieve multi-point or distributed Sensing; in medical devices, multi-core optical fibers can be used in endoscopes, fiber laser surgeries, etc.

Multi-core optical fiber can be mainly divided into concentric circular multi-core optical fiber and non-concentric circular multi-core optical fiber. The core layout of concentric multi-core fiber is concentric, which can achieve high-density core integration; the core layout of non-concentric multi-core fiber is non-concentric, which can reduce the The coupling between fiber cores improves the stability of data transmission.

With the development of technology, the number and density of multi-core optical fibers will be further increased, and the data transmission capacity will be further improved. At the same time, the application fields of multi-core optical fiber will also be further expanded. In addition to the existing application fields, it may also be used in emerging fields such as quantum communications and optical computing in the future.

The multi-core optical fiber products currently on the market mainly include Corning's ClearCurve multi-core optical fiber, Fujikura's SpiderWeb multi-core optical fiber, YOFC multi-core fiber etc. These products feature high-density fiber core integration and high data transmission capabilities.

To splice multi-core fiber, the special splicing machine is required. Currently in the market, Shinho S-22 multi-core splicer is a good choice to do so. It had been approved and use in actual construction.