What is the difference between OM1 OM2 OM3 OM4 and OM5 multimode fiber?
What is the difference between OM1 OM2 OM3 OM4 and OM5 multimode fiber?
Multimode fiber is a type of fiber used for short-distance transmission, commonly found in campus networks, corporate LANs, and data centers.
Today, the types of multimode fibers on the market include OM1, OM2, OM3, OM4, and OM5. These five types of multimode fibers have different data transmission capabilities.
With so many types of multimode fibers, do you wonder how to choose?
This article will focus on introducing the differences between OM1, OM2, OM3, OM4, and OM5 fibers.
We believe you will have a clearer understanding of the choice of multimode fibers after reading this article.
Multimode fiber types and differences
Compared with single-mode fiber, multi-mode fiber has a larger core diameter, usually 50 μm or 62.5 μm, and supports multiple optical modes to propagate.
According to the ISO 11810 standard, multi-mode fiber is divided into OM1, OM2, OM3, OM4 and OM5 fiber.
1. OM1 fiber refers to the multimode fiber with 850/1300nm window fully injected with bandwidth above 200/500MHz.km.
It uses LED light source, the core diameter is 62.5μm, and the outer sheath is usually orange. It can be used for Ethernet below 10Gbps. Most commonly used in Fast Ethernet.
Due to the larger diameter of the OM1 fiber core, it has strong light-gathering ability and bending resistance.
2. OM2 fiber refers to multimode fiber with 850/1300nm window fully injected with bandwidth above 500/500MHz.km.
It uses LED light source, the core diameter is 50μm, and the outer sheath is usually orange.
It can be used for Ethernet below 10Gbps.
Commonly used in Gigabit Ethernet. Compared with OM1 fiber, the core diameter of OM2 fiber is reduced, which effectively reduces the modal dispersion of multimode fiber, which increases the bandwidth and reduces the production cost by 1/3.
3. OM3 fiber is a laser-optimized multi-mode fiber.
This type of fiber uses an 850nm VCSEL laser light source, the core diameter is 50μm, and the outer sheath is aqua blue.
It can be used for Ethernet below 100Gbps, and is most commonly used for 10 Gigabit. in Ethernet.
Compared with OM1 and OM2 fibers, OM3 has higher transmission rate and bandwidth, so it is also called optimized multimode fiber or 10 Gigabit multimode fiber.
4. OM4 fiber is an upgraded version of OM3 multimode fiber, with better performance.
For example, the effective bandwidth of OM4 fiber is more than double that of OM3 fiber, compatible with OM3 fiber, and the outer sheath is aqua blue.
In Ethernet above 10Gbps, OM4 fiber can transmit farther than OM3 fiber, up to 400 meters.
5. OM5 fiber is the latest bandwidth multimode fiber, compatible with OM4 fiber, its core diameter is the same as OM2/OM3/OM4 fiber (50μm), and the outer sheath is lime green.
To learn more, visit How is OM5 Fiber Different from Existing Multimode Fiber? See OM5 Frequently Asked Questions for details .
All in all, the biggest difference between OM1, OM2, OM3, OM4 and OM5 multimode fiber is the difference in physics and application.
Different multimode fibers have different physical differences, mainly reflected in diameter, outer sheath color, light source and bandwidth, as shown in the following table:
Different multimode fibers are used in different Ethernet networks, and the maximum transmission distances supported are different, as shown in the following table:
Development Trend and Application of Multimode Fiber
Under the requirements of high-speed network applications, multimode fibers are developing towards low loss, high bandwidth and multi-wavelength multiplexing.
With the continuous improvement of optical fiber technology, multimode optical fiber has developed from the original OM1 optical fiber to the OM5 optical fiber that now supports 40/100G networks, and its performance is even better.
Today, OM1 and OM2 multimode fibers are mostly used for 1G Ethernet link connections in equipment rooms, OM3 and OM4 multimode fibers are mostly used for 10G/40G data center fiber cabling, and OM5 multimode fibers are used for 40/100G high-speed Ethernet. link transmission.
Compared with OM1/OM2/OM3/OM4 multimode fiber, OM5 multimode fiber has high scalability and flexibility, and can support higher-speed network transmission with fewer cores, and its cost and power consumption are far lower on single-mode fiber.
It can be seen that OM5 multimode fiber may be widely used in 100G/400G/1T ultra-large data centers in the future.
Frequently Asked Questions about Multimode Fiber
1. What is the difference between multimode fiber and single mode fiber?
Core diameter :
Multimode fiber has a larger core diameter (usually 50/62.5 μm), which can transmit light in multiple modes. Single-mode fibers have a small core diameter (usually 9 μm) and can transmit only one mode of light.
The bandwidth of single-mode fiber is generally higher than that of multi-mode fiber, which can be as high as 100,000 GHz.
Light source :
Multimode fiber generally uses LED light source, while single-mode fiber generally uses laser light source.
Multimode fiber is suitable for short-distance applications, usually up to 550m. Single-mode fiber is suitable for long-distance applications, and when the transmission distance exceeds 550m, single-mode fiber is preferred.
Multimode fiber typically costs less than singlemode fiber.
This article provides a detailed comparison of the differences between single-mode and multi-mode fibers: “The Differences Between Single-Mode Fiber and Multi-Mode Fiber and FAQs” .
2. Types of multimode fiber optic connectors
At present, common multimode fiber connectors (ie 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 fiber optic connector types.
The advantages, disadvantages and functions of these five fiber optic connectors are different, so what are the differences between them? The following table lists the differences in ferrule size, insertion loss, etc. of ST, SC, FC, LC and MTP/MPO connectors for multimode fiber:
Remarks: The ferrule refers to the precisely centered cylinder in the fiber optic connector plug, with a micro-hole in the center for fixing the fiber.
According to the different materials used in the ferrule, it is divided into ceramic ferrule, glass ferrule, plastic ferrule and metal ferrule.
3. Advantages of multimode fiber
Although single-mode fiber has advantages in terms of bandwidth and transmission distance, multi-mode fiber can support the transmission distance requirements of most indoor applications and data centers, and the installation and maintenance costs are much lower than single-mode fiber.
In addition, there are some significant advantages of multimode fiber, as described below:
Multi-user backbone network without loss and interference :
The biggest feature of multi-mode fiber is that it can carry multiple optical signals on the same link at the same time.
What’s more, there is almost no loss of optical signal power.
Therefore, network users can send multiple data packets simultaneously in multimode fiber optic patch cords, and all information will be safely transmitted to the destination without any interference, and remain unchanged.
Multiple Protocols Supported :
Multimode fiber supports multiple data transmission protocols, including Ethernet, InfiniBand, and Internet Protocol. Therefore, people regard multimode fiber as the basis for realizing the core application.
4. Can multimode fiber be used as single mode?
No, because of the large dispersion and loss of multimode fibers, optical signals cannot be transmitted over long distances on multimode fibers.