Multi-mode Fiber

Multimode optical cable, also known as multimode optical fiber, has a thicker core (50 or 62.5 μm) and can transmit multiple modes of light. However, its intermodal dispersion is relatively large, which limits the frequency of digital signal transmission, and this limitation worsens with increasing distance. Therefore, multimode optical fiber transmission distances are relatively short, typically only a few kilometers.

Send Inquiry

Description

Technical Parameters

our company

30+ years

Our factory was found in 1992, first start with coaxial cable which was one of the biggest manufacturers in lin'an city.In year of 2001 started focusing on the production of optical cables.

30+ countries

In year of 2008, set up international sales department and have long-term cooperation with more than 30 countries and have 18 years` rich experience to export cables .

What are the differences between OM1, OM2, OM3, and OM4 optical fibers?

"OM" stands for optical multimode, a standard for indicating the grade of multimode fiber. Different grades have different bandwidths and maximum transmission distances. This article will mainly explain the differences between OM1, OM2, OM3, and OM4 optical fibers.

OM1

OM1 refers to 50µm or 62.5µm core diameter multimode fiber with a full injection bandwidth of 200/500MHz·km or higher at 850/1300nm.

OM2

OM2 refers to 50µm or 62.5µm core diameter multimode fiber with a full injection bandwidth of 500/500MHz·km or higher at 850/1300nm.

OM3

OM3 is a 50µm core diameter multimode fiber optimized for 850nm lasers. In 10Gb/s Ethernet using 850nm VCSELs, the fiber transmission distance can reach 300m.

OM4

OM4 is an upgraded version of OM3 multimode fiber, with a fiber transmission distance of up to 550m.

Design Fundamentals

OM1&OM2

Traditional OM1 and OM2 multimode fibers use LEDs (Light Emitting Diodes) as the primary light source in both standards and design. OM3 and OM4, however, are optimized from OM2 to also support transmission using LDs (Laser Diodes).

oM3

Compared to OM1 and OM2, OM3 offers higher transmission rates and bandwidth, hence the name "optimized multimode fiber" or "10 Gigabit multimode fiber."

OM4

OM4 is further optimized from OM3, resulting in even better performance.

Application

Multi mode fiber allows multiple beams of light to propagate simultaneously, resulting in mode dispersion (because each mode enters the fiber at a different angle, and their arrival times at the other end are also different; this characteristic is called mode dispersion). Mode dispersion technology limits the bandwidth and distance of multimode fiber. Therefore, multimode fiber has thick cores, low transmission speed, short distance, and poor overall transmission performance. However, its cost is relatively low compared to other products, and it is generally used in buildings or in environments where they are geographically adjacent.

Functions and Features

Choose the fiber that suits you best.

OM1

Larger core diameter and numerical aperture, providing strong light-gathering ability and bending resistance;

OM2

Smaller core diameter and numerical aperture, effectively reducing modal dispersion in multimode fiber, significantly increasing bandwidth, and reducing manufacturing costs by one-third;

OM3

Employs a flame-retardant outer sheath, preventing flame spread, smoke emission, acidic gases, and toxic gases, while meeting the requirements of 10Gb/s transmission rates;

OM4

Developed for VSCEL laser transmission, offering more than twice the effective bandwidth of OM3.

Application Scope

01.

Non-contact dispensing technology

OM1 and OM2 have been widely deployed in building interiors for many years, supporting Ethernet transmission up to 1Gb;

02.

spary read laser welding technology

OM3 and OM4 optical cables are typically used in data center cabling environments, supporting 10G and even 40/100G high-speed Ethernet transmission.

When to Use OM3 Fiber Optic Patch Cords?

OM3 fiber optic cables are designed to work with VCSELs and conform to the ISO/IEC 11801-2nd OM-3 fiber optic specification, meeting the requirements of 10 Gigabit Ethernet applications. OM3 fiber optic cables are available in various types, including indoor and indoor/outdoor universal types, with core counts ranging from 4 to 48. They also support all applications based on older multimode 50/125μm fiber optics, including support for LED and laser light sources.

Using OM3 fiber optic systems, the transmission distance for Gigabit Ethernet can be extended to 900 meters, meaning that users do not need to use expensive laser devices when the distance between buildings exceeds 550 meters.

Within a distance of 2000 meters, standard 62.5/125μm multimode fiber can be used for various situations within the OC-12 (622Mb/s) rate range; otherwise, single-mode fiber is used. However, the emergence of OM3 multimode fiber has changed this situation. Since OM3 fiber can improve the transmission distance of gigabit and 10-gigabit systems, using 850nm wavelength optical modules with VCSELs will be the most cost-effective cabling solution.

When the link length exceeds 1000 meters, single-mode fiber remains the only option. Single-mode fiber can achieve a transmission distance of 5 kilometers at a wavelength of 1310nm in gigabit systems and 10 kilometers in 10-gigabit systems.

When the link length is less than or equal to 1000 meters, OM3 50μm multimode fiber can be used in gigabit systems, while single-mode fiber should be used in 10-gigabit systems.

When the link length is less than 300 meters, OM3 multimode fiber can be used in any gigabit and 10-gigabit system.

When to use OM4 fiber optic patch cords?

For a typical link, the cost of optical modules is quite expensive. Although single-mode fiber is cheaper than multimode fiber, its use requires very expensive 1300nm optical modules, which cost approximately 2-3 times more than 850nm multimode optical modules. Overall, the cost of a multimode fiber system is significantly lower than that of a single-mode fiber system.

When investing in fiber optic cabling, considering an initial investment in higher-quality multimode fiber, such as OM4 fiber, can ensure full utilization of current multimode fiber technology and reduce the overall cost of the current system. When the system needs to be upgraded to higher speeds, such as 40G and 100G, OM4 can still be used and will be even more cost-effective.

In short, when the transmission rate is greater than 1Gb/s, using multimode fiber is a good system choice. When the system requires even higher transmission rates, the following are our guidelines for selecting OM4 fiber:

For Ethernet users, transmission distances can reach 300m to 600m in 10Gb/s systems; in 40Gb/s and 100Gb/s systems, the transmission distance is 100m to 125m.

For campus network users, OM4 fiber will support 400m for 4Gb/s fiber links, 200m for 8Gb/s fiber links, or 130m for 16Gb/s fiber links.