Original Band (O-band)

Last updated on 05/7/2021


The O-band, ranging from 1260 nm to 1360 nm, stands for the original band. It was “originally” considered as the primary telecommunication wavelength band used for optical communication in the mid 1970s due to the following two reasons:

  1. Optical fibers at that time exhibited the lowest attenuation near the O-band, not in the C-band. In the mid 1970s, the optical fiber manufacturing technique was still in its early stage, and water (OH group) inpurity remained in the silica glass matrix. This inpurity resulted in an absorption band peaked at 1383 nm, and the tail of this absorption band increased the attenuation in the C-band.
  2. Silica glass has a zero material dispersion wavelength in the O-band, and thus it was expected that signal distortion – arising from fiber chromatic dispersion – would be minimized.

Now optical fiber manufacturing technology has matured and nearly compete elimination of this inpurity is enabled; the lowest-attenuation wavelength has moved to the C-band. The O-band is, however, still in extensive use for optical communication, mainly because the standard telecom optical fiber (ITU-T G.652 ) exhibits its zero dispersion in the O-band.


High-speed Ethernet

The O-band is extensively used for high-speed Ethernet transmission, such as IEEE 100GBASE-LR4 or 400GBASE-LR8. Small fiber dispersion in the O-band enables high-speed optical transmission without dispersion compensation schemes, such as dispersion-compensation fibers and digital-coherent detection. Optical communication system with no dispersion-compensation scheme offers advantages in both the initial investment (lower transceiver price) and operation cost (lower power consumption); both are key requirements for a data center where high-speed Ethernet is heavily used.

Passive-optical network (PON)

The O-band is often used in PON systems as the upstream wavelength. Below is a list of upstream wavelengths used in various PON standards.

Standardization body Standard Upstream wavelength (nm)
IEEE GE-PON (US, DS: 1Gbps) 1260-1360
10GE-PON (US: 1Gbps, DS: 10Gbps) 1260-1360
10GE-PON (US, DS: 10Gbps) 1260-1280
ITU-T G-PON (US: 2.5Gbps, DS: 1.25Gbps) 1260-1360 (Regular)
XG-PON1 (US: 2.5Gbps, DS: 10Gbps) 1260-1280
XG-PON2 (US, DS: 10Gbps) 1260-1280

US: UpStream, DS: DownStream

FiberLabs’ O-band product lineup

FiberLabs offer a wide range of optical instruments operating in the O-band, such as praseodymium-doped fiber amplifier (PDFA), ASE, and SLD sources. FiberLabs is the only supplier of PDFA and has supplied a large number of PDFAs for various 100G/400G Ethernet applications (test & measurements, reach extension, network tapping…). Please check the following link for product details, and feel free to contact us for your specific needs.

FiberLabs’ O-band lineup O-band PDFA Bench top type 19-inch 1U-type Module type Module type (compact size) O-band ASE source Bench-top type Module type O-band SLD source Bench-top type Bench-top type (wide-band) O/E/S/C/L-band SLD source Benth-top type O-band LD source Bench-top type O-band tunable filter Bench-top type


“G.652 : Characteristics of a single-mode optical fibre and cable,” <https://www.itu.int/rec/T-REC-G.652/en>.