What is OM4 Fiber?
:: What Is OM4 Fiber Anyway?
OM4 fiber is a laser-optimized, high bandwidth 50um multimode fiber. OM4 fiber is not a new fiber type. All major fiber manufacturers have been selling a fiber with an effective modal bandwidth (EMB) value equivalent to that specified by OM4 since 2005. The change is that there is now a standard that is specifically targeted at this product. Prior to the standardization of OM4, these higher bandwidth fibers were sold as a part of OM3.
OM3 and OM4 fiber are referred to as “laser-optimized” multimode fibers because they are specifically designed for optimum performance when used with low cost Vertical-Cavity-Surface-Emitting-Lasers (VCSELs).
OM4 fiber is designed to enhance the system cost benefits enabled by 850nm VCSELs for existing 1 Gb/s and 10 Gb/s applications as well as future 40 Gb/s and 100 Gb/s systems.
OM4 fiber supports Ethernet, Fibre Channel, and OIF applications, allowing extended reach upwards of 550 meters at 10 Gb/s for ultra long building backbones and medium length campus backbones.
:: Why Is It Called OM4?
Multimode fibers are identified by the OM (“optical mode”) designation as outlined in the ISO/IEC 11801 standard.
- OM1, for fiber with 200/500 MHz*km overfilled launch (OFL) bandwidth at 850/1300nm (typically 62.5/125um fiber)
- OM2, for fiber with 500/500 MHz*km OFL bandwidth at 850/1300nm (typically 50/125um fiber)
- OM3, for laser-optimized 50um fiber having 2000 MHz*km effective modal bandwidth (EMB, also known as laser bandwidth), designed for 10 Gb/s transmission.
- OM4, for laser-optimized 50um fiber having 4700 MHz*km EMB bandwidth designed for 10 Gb/s, 40 Gb/s, and 100 Gb/s transmission.
:: OM4 Fiber Standard
The TIA/EIA approved OM4 specification in its TIA-492AAAD in 2009. IEC’s document covering OM4 standard is IEC 60793-2-10 as fiber type A1a.3.
:: Bandwidth Comparison of OM1, OM2, OM3, and OM4 Fibers
The following table shows the bandwidth comparison among OM1, OM2, OM3 and OM4 fibers.
|
Multimode Fiber
|
Bandwidth (MHz * km)
|
||||
|
OM Designation
|
TIA Fiber Standard
|
Fiber Type |
Overfilled Launch (OFL)
@850nm |
Effective Modal Bandwidth (EMB)
@850nm |
Overfilled Launch (OFL)
@1300nm |
|
OM1
|
492-AAAA
|
62.5/125
|
200
|
n/s
|
500
|
|
OM2
|
492-AAAB
|
50/125
|
500
|
n/s
|
500
|
|
OM3
|
492-AAAC
|
50/125
|
1500
|
2000
|
500
|
|
OM4
|
492-AAAD
|
50/125
|
3500
|
4700
|
500
|
The following table and graph shows the maximum distance different multimode fibers can carry.
|
Applications
|
Wavelength(nm)
|
Maximum Channel Length (meters)
|
|||
|
OM1
|
OM2
|
OM3
|
OM4
|
||
| Fibre Channel | |||||
| 4 Gb/s |
850
|
70
|
150
|
380
|
400
|
| 8 Gb/s |
850
|
21
|
50
|
150
|
200
|
| 16 Gb/s |
850
|
15
|
35
|
100
|
130
|
| Ethernet | |||||
| 1 Gb/s |
850
|
275
|
550
|
800
|
1100
|
| 10 Gb/s |
850
|
33
|
82
|
300
|
550
|
| 40 & 100 Gb/s |
850
|
n/s
|
n/s
|
100
|
125
|
| 1 Gb/s |
1300
|
550
|
550
|
550
|
550
|
| 10 Gb/s |
1300
|
220 |
220
(10GBase-LRM) 300 (10Gbase-LX4) |
220 |
220 |
:: OM4 Fiber Optic Cable Assemblies Available from Fiber Optics For Sale Co.
Fiber Optics For Sale Co. offers factory direct OM4 Fiber – Standard and custom OM4 Fiber Optic Assemblies, built to specs OM4 fiber assemblies, OM4 fibre channel cables for quality installations.
The following list shows the OM4 cable assembly products we carry.
- OM4 Clear Curve Multimode Fiber Optic Assemblies
- OM4 Infinicor eSX Multimode Fiber Optic Assemblies
- OM4 Fibre Channel Cables, Standard and Custom Fibre Channel cable Assemblies
- Other OM4 Fiber Assemblies, Custom OM4 Fiber, Built to Specs OM4 Fiber Assemblies