Optical fiber is an optical fiber, which is a kind of fiber made of glass or plastic. It is a light transmission tool using the principle of total internal reflection of light in these fibers.

What are the characteristics of optical fiber?

If the optical fiber is packaged in a plastic protective sleeve, it can be bent without breaking, and is an excellent signal transmission tool

The loss of optical fiber in the transmission process is much lower than that of electric wire. The optical transmission loss of better optical fiber is only 0.2 decibel per kilometer; That is to say, only 4.5% is lost after one kilometer of transmission; So now long-distance electricity transmission is using high-voltage lines to reduce power loss.

The main raw material of optical fiber is silicon, which has huge reserves, is easy to exploit and relatively cheap; The content in the earth's crust is only lower than that of oxygen, accounting for about a quarter of the surface rocks. However, there is a disadvantage that silicon is mainly in the form of oxygenated compounds, so in industry, it is necessary to use high-purity C (carbon) in electric furnaces for reduction reaction.

What is the principle of optical fiber?

A bundle of optical fibers is a bit like a long-distance flashlight

Optical fiber is a cylindrical dielectric waveguide, which uses the principle of total internal reflection to conduct light. Since there is no loss of light when reflecting, the signal can be transmitted to a very long distance.

What is the principle of total internal reflection?

Generally speaking, this is an optical phenomenon. When light passes through two media with different refractive index, part of the light will be refracted at the interface of the media, and the rest will be reflected. However, when the incidence angle is larger than the critical angle (the ray is far away from the normal), the ray will stop entering the other interface, and all the rays will be reflected towards the inner surface!