What Bands Does Optical Communication Have

As the name implies, optical fiber communication is the communication in which light is used as the information carrier and optical fiber as the transmission medium. However, not all light is suitable for optical fiber communication. Different wavelengths of light (which can be simply understood as light with different colors) lead to different transmission losses in optical fibers. The light with large transmission loss can not carry information in the optical fiber.

After long-term research by scientists, it was first discovered that the light with a wavelength of 850nm can be used as the light for optical communication, and this band is also directly called the 850nm band. However, the transmission loss in the wavelength region of 850 nm band is relatively large, and there is no suitable optical fiber amplifier. Therefore, 850 nm band is only suitable for short range transmission.

Then, scientists explored the optical band of "low loss wavelength region", that is, the light in the 1260nm~1625nm region, which is most suitable for transmission in optical fibers.

The 1260nm~1625nm region is subdivided into five bands: O band, E band, S band, C band and L band.