There are different types of fiber optic cable. Some types are single-mode, and some types are multimode. Multimode fibers are described by their core and cladding diameters. Usually the diameter of the multimode fiber is either 50/125 µm or 62.5/125 µm. At present, there are four kinds of multi-mode fibers: OM1, OM2, OM3, OM4 and OM5. The letters “OM” stand for optical multimode. Each type of them has different characteristics.
Standard
Each "OM" has a minimum Modal Bandwidth (MBW) requirement. OM1, OM2, and OM3 fiber are determined by the ISO 11801 standard, which is based on the modal bandwidth of the multimode fiber. In August of 2009, TIA/EIA approved and released 492AAAD, which defines the performance criteria for OM4. While they developed the original “OM” designations, IEC has not yet released an approved equivalent standard that will eventually be documented as fiber type A1a.3 in IEC 60793-2-10.
Specifications
● OM1 cable typically comes with an orange jacket and has a core size of 62.5 micrometers (µm). It can support 10 Gigabit Ethernet at lengths up 33 meters. It is most commonly used for 100 Megabit Ethernet applications.
● OM2 also has a suggested jacket color of orange. Its core size is 50µm instead of 62.5µm. It supports 10 Gigabit Ethernet at lengths up to 82 meters but is more commonly used for 1 Gigabit Ethernet applications.
● OM3 fiber has a suggested jacket color of aqua. Like OM2, its core size is 50µm. It supports 10 Gigabit Ethernet at lengths up to 300 meters. Besides OM3 is able to support 40 Gigabit and 100 Gigabit Ethernet up to 100 meters. 10 Gigabit Ethernet is its most common use.
● OM4 also has a suggested jacket color of aqua. It is a further improvement to OM3. It also uses a 50µm core but it supports 10 Gigabit Ethernet at lengths up 550 meters and it supports 100 Gigabit Ethernet at lengths up to 150 meters.
● OM5 fiber, also known as WBMMF (wideband multimode fiber), is the newest type of multimode fiber, and it is backwards compatible with OM4. It has the same core size as OM2, OM3, and OM4. The color of OM5 fiber jacket was chosen as lime green. It is designed and specified to support at least four WDM channels at a minimum speed of 28Gbps per channel through the 850-953 nm window. More details can be found at: Three Critical Focuses on OM5 Fiber Optic Cable
Diameter: The core diameter of OM1 is 62.5 µm , however, core diameter of the OM2, OM3 and OM4 is 50 µm.
|
Multimode Fiber Type |
Diameter |
|
OM1 |
62.5/125µm |
|
OM2 |
50/125µm |
|
OM3 |
50/125µm |
|
OM4 |
50/125µm |
|
OM5 |
50/125µm |
Jacket Color: OM1 and OM2 MMF are generally defined by an Orange jacket. OM3 and OM4 are usually defined with an Aqua jacket. OM5 is usually defined with a Lime Green jacket.
| Multimode Cable Type | Jacket Color |
| OM1 | Orange |
| OM2 | Orange |
| OM3 | Aqua |
| OM4 | Aqua |
| OM5 | Lime Green |
Optical Source: OM1 and OM2 commonly use LED light source. However, OM3 and OM4 usually use 850nm VCSEL.
| Multimode Cable Type | Optical Source |
| OM1 | LED |
| OM2 | LED |
| OM3 | VSCEL |
| OM4 | VSCEL |
| OM5 | VSCEL |
Bandwidth: At 850 nm the minimal modal bandwidth of OM1 is 200MHz*km, of OM2 is 500MHz*km, of OM3 is 2000MHz*km, of OM4 is 4700MHz*km, of OM5 is 28000MHz*km.
| Multimode Cable Type | Bandwidth |
| OM1 | 200MHz*km |
| OM2 | 500MHz*km |
| OM3 | 2000MHz*km |
| OM4 | 4700MHz*km |
| OM5 | 28000MHz*km |
How to choose the Multimode Fiber?
Multimode fibers are able to transmit different distance ranges at various data rate. You can choose the most suited one according to your actual application. The max multimode fiber distance comparison at different data rate is specified below.
|
Fiber Optic Cable Type |
Fiber Cable Distance |
|||||||
|
|
Fast Ethernet 100BA SE-FX |
1Gb Ethernet 1000BASE-SX |
1Gb Ethernet 1000BA SE-LX |
10Gb Base SE-SR |
25Gb Base SR-S |
40Gb Base SR4 |
100Gb Base SR10 |
|
|
Multimode fiber |
OM1 |
200m |
275m |
550m (mode conditioning patch cable required) |
/ |
/ |
/ |
/ |
|
|
OM2 |
200m |
550m |
|
/ |
/ |
/ |
/ |
|
|
OM3 |
200m |
550m |
|
300m |
70m |
100m |
100m |
|
|
OM4 |
200m |
550m |
|
400m |
100m |
150m |
150m |
|
|
OM5 |
200m |
550m |
|
300m |
100m |
400m |
400m |
Post time: Sep-03-2021