Different materials reflect and absorb differently at different wavelengths. Optical remote sensing makes use of visible, near infrared and short-waveinfrared sensors to form images of the earth's surface by detecting thesolar radiation reflected from targets on the ground. With world-leading optical amplification technology, FiberLabs presently provides optical amplifiers of a variety of wavelength bands, including 850nm-, 980 nm-, 1030nm-, O-, S-, C-, L-, CL-, and SCL-bands. With the original fluoride fiber technology, FiberLabs has successfully developed optical fiber amplifiers for the O- and S-bands and 850 nm of wavelengths. Though various wavelength bands of the O-, S-, C- and L- bands have come into use with the explosive expansion of internet traffic in recent years, optical fiber amplifiers for the O- and S-band wavelengths were not realized for many years because of many technical hurdles. The U-band is mainly used for network monitoring purposes.įiberLabs’ product lineup for optical communication ![]() The 850-nm-band is the primary wavelength for multimode fiber optical communication systems, combined with VCSEL (Vertical-Cavity Surface Emitting Laser). In addition to the O- to L-bands, there are two more wavelength bands, namely the 850-nm-band and U-band (ultra-long-wavelength band: 1625-1675 nm). The use of the E-band in optical communication is, nevertheless, still limited as many existing fiber optic cables installed before 2000 show high attenuation in the E-band. After the invention of dehydration technique during glass production, the attenuation of most commonly used optical fiber ( ITU-T G.652.D) in the E-band has become lower than that in the O-band. This is because the attenuation of early optical fiber in the E-band was highest among the five bands, due to residual water (OH group) impurity remained in the glass. The E-band (extended-wavelength band: 1360-1460 nm) is the least common wavelength band among the five. The S-band is also gathering attention for DWDM transmission as a future R&D topic, further extending the bandwidth of terrestrial optical network beyond the C+L-band. The loss of optical fiber in the S-band (short-wavelength band: 1460-1530 nm) is lower than that of the O-band, and the S-band is used for many PON (Passive-Optical Network) systems as the downstream wavelength. Repeatered C+L-band WDM transmission is now commercially feasible, and is employed even for transoceanic submarine transmission systems (see here). The same WDM and EDFA technologies can be applied to the L-band. The L-band is the second lowest-loss wavelength band, and is a popular choice when the use of the C-band is not sufficient to meet the bandwidth demand. ![]() Today optical fibers show its lowest loss in the C-band, and thus is commonly used in many metro, long-haul, ultra-long-haul, and submarine optical transmission systems combined with the WDM and EDFA technologies. It was also because optical fibers produced in the mid 1970s showed its lowest loss near the O-band. Among these five bands, the O-band (orignal band: 1260-1360 nm) was historically the first wavelength band used for optical communication, because signal distortion (due to chromatic dispersion) is minimum.
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