Home  >  Info Center  >  FAQ  > 

How does fibre optic work?

How does fibre optic work?

2020-09-26

If you compare the Internet to an information highway, optical cables are like the cornerstones of highways. Then how do large-capacity information optical cables transmit high-speed and long-distance?


At the transmitting end, the information to be transmitted (such as voice) is first converted into an electrical signal, and then emitted to the laser beam through a laser. The intensity of the light will change with the frequency of the electrical signal, and it will be emitted through the optical fiber. At the receiving end, detection After receiving the optical signal, the device turns it into an electrical signal, and restores the original information after processing.


The optical fiber made of glass fiber inside the optical fiber can transmit the optical signal to thousands of kilometers away, and combine hundreds or thousands of optical fibers to form an optical cable like a cable, which improves the strength of the optical fiber , And greatly increase the communication capacity.


The propagation speed of light in different substances is different, so when it is shot from one substance to another, refraction and reflection will occur at the junction of the two substances, and the angle of the refracted light will vary with the angle of the incident light However, when the angle of the incident light reaches or exceeds a certain angle, the refracted light will disappear and all the incident light will be reflected back, which is the total reflection of light.


The optical signal is transmitted to the end after repeated refraction in the optical fiber. The optical signal will be scattered or attenuated after refraction, and the optical signal needs to be amplified every 50 kilometers.


The following is a schematic diagram of the working principle of optical fiber:


1. The principle of total reflection

If the light beam is directed from the optically dense medium to the optically thin medium, the refraction angle is greater than the incident angle, as shown in the figure.



If θ0 is continuously increased, the refraction angle θ1 can reach 90°, at this time θ1 is called the critical angle.

When the light radiates from the optically dense medium to the optically thin medium, and the incident angle is greater than the critical angle, total reflection will occur.



Optical fiber uses this total reflection to transmit optical signals.

Fiber Hope has been focusing on the R&D and sales of optical fiber products for 16 years, and the product quality has been well received by customers. Fiber Hope manufacturer sales email: sales001@fh-fiber.com. Consultation telephone: +8615296530925. If you have a need for high-quality standard optical cable/fiber products, you may wish to consider the Fiber Hope brand.



Chat Online 编辑模式下无法使用
Chat Online inputting...