The multimode cable consists of glass fibers with a standard diameter of 50 to 100 microns for the light-carrying element, a type of optical fiber used for short-distance transmission commonly used in campus networks, enterprise LANs, and data centers.
Today, the types of multimode fiber on the market are OM1, OM2, OM3, OM4, and OM5, all of which have different data transmission capabilities. With so many types of multimode fiber, do you know how to make a choice?
This article will focus on the differences among OM1, OM2, OM3, OM4, and OM5 fiber, so you will have a clearer understanding of the choice of multimode fiber.
Types and Differences of Multimode Fibers
Multimode fibers have a larger core diameter than single-mode fibers, typically 50μm or 62.5μm. It supports multiple optical mode propagation. According to the ISO 11810 standard, multimode fibers are divided into OM1, OM2, OM3, OM4, and OM5.
1, OM1 fiber typically comes with an orange jacket with a core size of 62.5 µm. It can support 10 Gigabit Ethernet at lengths of up to 33 meters. It is most commonly used for 100 Megabit Ethernet applications. This type commonly uses a LED light source.
2, OM2 refers to a 50um or 62.5um core-diameter multimode fiber with a total injection bandwidth of 500/500MHz.km at 850/1300nm; The outer sheath is usually orange and can be used for Ethernet below 10Gbps, most commonly used in Gigabit Ethernet.
3, OM3 is an 850nm laser-optimized 50um core-diameter multimode fiber with an aqua outer sheath. In 10Gb/s Ethernet with 850nm VCSEL, the fiber transmission distance can reach 300m. Compared with OM1 and OM2 fiber, OM3 has a higher transmission rate and capacity, so it is also called optimized multimode fiber or 10GbE multimode fiber.
4, OM4 optical fiber is an upgraded version of OM3 multimode optical fiber, and the fiber transmission distance can reach 550m. For example, the adequate bandwidth of OM4 optical fiber is more than twice that of OM3 optical fiber, which is compatible with OM3 optical fiber, and its outer sheath is aqua. In Ethernet above 10Gbps, OM4 optical fiber has a longer transmission distance of 400m than OM3 optical fiber.
5, OM5 fiber is a new generation of multimode fiber. It was just standardized in recent years. Different from OM1, OM2, OM3, and OM4, OM5 fiber is designed to work over a wide range of wavelengths between 850nm and 950nm. And it supports SWDM (shortwave wavelength division multiplexing) technology which can reduce fiber counts in optical transmission and is compatible with OM4 fiber. The outer sheath is lemon green.
In a word, the most significant difference among OM1, OM2, OM3, OM4, and OM5 multimode fibers lies in their physical and application differences, details as follows,
1, Physical Differences
Different multimode optical fibers have distinct physical differences, mainly in diameter, outer sheath color, light source, and bandwidth, as shown in the following table:
2, Application Differences
Different multimode optical fibers are used in various Ethernet networks and support different maximum transmission distances, as shown in the following table:
Development Trend and Application of Multi-mode Optical Fiber
In demand for high-speed network applications, multimode fiber is developing towards low loss, high bandwidth, and multi-wavelength multiplexing. With the continuous improvement of optical fiber technology, multimode optical fiber has grown from the original OM1 optical fiber to the OM5 optical fiber supporting a 40/100G network with better performance. Nowadays, OM1 and OM2 multimode optical fibers are mainly used for 1G Ethernet link connection in the computer room, OM3 and OM4 multimode optical fibers are used primarily for 10G/40G data center optical fiber cabling, and OM5 multimode optical fibers are suitable for 40/100G high-speed Ethernet link transmission. Compared with OM1/OM2/OM3/OM4 multimode fiber, OM5 has high scalability and flexibility, can support higher speed network transmission with fewer cores, and its cost and power consumption are far lower than single-mode fiber. It can be seen that OM5 multimode fiber is likely to be widely used in 100G/400G/1T super large data centers in the future.
FAQs for Multi-mode Fiber
1, What is the difference between multi-mode fiber and single-mode fiber?
2, Multi-mode Fiber Connector Type
At present, standard multimode optical fiber connectors (i.e., connectors) include ST, SC, FC, LC, MU, E2000, MTRJ, SMA, DIN, and MTP&MPO, among which ST, SC, FC, LC, and MTP/MPO are the most commonly used optical fiber connector types.
3, Advantages of Multimode Fiber
Although single-mode fiber has advantages in bandwidth and transmission distance, multimode fiber can support the transmission distance requirements of most indoor applications and data centers, and its installation and maintenance costs are far lower than single-mode fiber. In addition, multimode fiber has some significant advantages, as described below:
1), The most prominent feature of multimode fiber is that it can carry multiple optical signals on the same link simultaneously. More importantly, there is almost no loss of optical signal power. Therefore, network users can send multiple data packets simultaneously in the multimode optical fiber jumper. All information will be safely transmitted to the destination without interference and remain unchanged.
2), Multimode fiber supports multiple data transmission protocols, including Ethernet, unlimited bandwidth, and Internet protocols. Therefore, people regard multimode fiber as the basis for realizing core applications.
4, Can Multi-mode Fiber be used as Single Mode?
No, because the dispersion and loss of multimode fiber are large, optical signals cannot be transmitted over a long distance on multimode fiber.