What is the history of fibre optic communication technology?

Generally speaking, transmission of information consists of the following three links: acquisition of information, exchange of information and transmission of information.

Fibre-optic communication is one of the information transmission links.

There are two necessary prerequisites for information transmission:

a. Reliable signal source ---- in fibre optic communication is a laser.

b. A good transmission medium ---- is the optical fibre in optical fibre communication.

With the successive appearance of these two necessary conditions, optical fibre communication began its rapid development, kicking off the technology of optical fibre communication, which is one of the most important means of transmission in the communication industry.

It is easy to imagine that the use of light in the air in a straight line propagation characteristics of atmospheric transmission of optical communications, do not need any line, simple, economical. 1960 Maiman (T.H. Maiman) invented the ruby laser, produced a monochromatic coherent light, so that high-speed light modulation is possible.

Since then there have been various experiments on atmospheric transmission systems, but later it was found that there were many serious problems with atmospheric transmission of optical communications, which made it impractical to use.

In 1966. the British Chinese Charles Kao (C.K. Kao) and Hockham foresaw the use of glass can be made to attenuate 20dB/km communication optical fibre (referred to as optical fibre).

At that time, the world's best optical glass attenuation of 1000dB/km or so.

In 1970. the United States Corning Glass Company first made the attenuation of 20dB/km optical fibre, a major breakthrough. Make optical fibre communication possible.

In 1974. the optical fibre attenuation reduced to 2dB/km.

In 1980. the optical fibre attenuation as low as 0.2dB/km (in 1.55μm long wavelength low attenuation window), close to the theoretical value. This made long-distance optical fibre communication possible.

Moreover, due to the continuous improvement of the purification process, the transmission window of the optical fibre was moved from the short wavelength window of 0.85 μm to the long wavelength low attenuation windows of 1.3 μm and 1.55 μm.

After 1976. various practical optical fibre communication systems appeared one after another. In 1980. many countries around the world developed commercial optical fibre communication systems. Since then, optical fibre communication has taken a big step into the commercial period.

Since the commercialisation of optical fibre, the varieties of optical fibre have gone through several important stages of development with the continuous development of technology.