Comparison of Multimode Fiber Types

Classification and application comparison of multimode optical fiber. Due to the large core diameter, multimode fiber can be used with low-cost light sources, so it has a wide range of applications in short-distance transmission scenarios, such as data centers and local area networks.

Multimode Fiber Classification

According to the standard ISO/IEC 11801 specification, multimode fibers are divided into five categories: OM1, OM2, OM3, OM4, and OM5, all of which belong to graded index multimode fibers. The comparison of outer diameter size is shown in Figure 1. "OM" stands for optical multi-mode, that is, optical mode, which is a standard for multimode fiber to indicate the level of fiber.

Multimode Fiber Parameters

Bending capacity

There are many transmission modes in the multimode fiber, which brings about the problem of the bending resistance of the fiber. When the fiber is bent, the high-order modes are easily leaked out, resulting in signal loss, that is, the bending loss of the fiber. With the increasing number of indoor application scenarios, the wiring of multimode optical fibers in narrow environments also puts forward higher requirements for their bending resistance. Comparison of the bending resistance of five types of optical fibers.

Attenuation coefficient

Optical fiber attenuation value (also known as attenuation coefficient) is one of the most important characteristic parameters of multimode optical fiber, which determines the relay distance of multimode optical fiber to a large extent, which is mainly determined by the inherent loss of optical fiber, bending loss, extrusion Influenced by factors such as loss, impurity absorption, and whether the material is uniform, the attenuation values ​​of five types of commonly used multimode fibers are compared.

Full injection bandwidth & link length

The traditional OM1 and OM2 multimode optical fibers use LED (Light Emitting Diode) as the basic light source in terms of standard and design, while OM3 and OM4 are optimized on the basis of OM2, making them suitable for LD light sources at the same time (Laser Diode laser diode) transmission; compared with OM1 and OM2, OM3 has a higher transmission rate and bandwidth, and OM4 has better performance than OM3. OM5 optical fiber jumper is optimized in the manufacturing process of optical fiber preform, so it can support higher bandwidth. In terms of structure, it is no different from OM3 and OM4 fiber optic patch cords, so it is fully backward compatible with traditional OM3 and OM4 multimode fiber optic patch cords. With the continuous iterative upgrade of technology, the full injection bandwidth of multimode fiber continues to increase, and the link length is also different. The attenuation coefficient and link length of five commonly used multimode fibers are compared.

With the continuous improvement of application requirements, multimode fiber is developing in the direction of low bending loss, high bandwidth, and multi-wavelength multiplexing. In the future, there will be more and more demands for multimode fiber in industry applications.