Can you tell me more about fiber optics 20

Chinese name: optical fiber English name: optical fiber Other name: optical fiber Definition: A waveguide medium that transmits light energy, generally composed of fiber core and cladding.

Optical fiber is the abbreviation of optical fiber, which is a light conduction tool that uses the principle of total reflection of light in fibers made of glass or plastic. Former President of the Chinese University of Hong Kong, Charles Kao and George AHockham was the first to propose the idea that optical fiber could be used for communication transmission, for which Charles Kao was awarded the Nobel Prize in Physics in 2009.

To put it simply, optical fiber is to transmit information, such as monitoring needs, operator needs, system integration needs, highway needs, etc., which are extracted from the stones. Optical fibers are also different, single-mode, multi-mode, single-mode and multi-mode, that is, the transmission mode, speed, and size are different. Optical fibers can only be used when they are processed into optical cables, because optical fibers are too fragile and need something to protect, so they are made into optical cables, with PE and steel wires outside.

The definition you have to figure out that broadband is divided into ADSL broadband and fiber broadband, the opposite of broadband is narrowband, which cannot be juxtaposed with optical fiber, and optical fiber is just an access method. Theoretically, the speed of the same megabit fiber and ADSL broadband is the same. The characteristics of optical fiber are only relatively stable, the Internet speed will not be too slow during peak hours, and then the propagation process is long, the signal loss is small, the biggest feature is of course the same upload and ** speed, which is incomparable to ADSL, fast upload speed is very important for playing games with high-quality data upload, but now ordinary optical fiber seems to be limited by the operator The upload speed is still limited, and the dedicated channel is equal, the cost is particularly high, and ordinary users are not recommended to use optical fiber, Don't listen to people talking about how fast fiber is, you need to understand how it works.

1) Large communication capacity and long transmission distance; The potential bandwidth of one fiber can reach 20thz. With such a bandwidth, it only takes one second to transmit all the written data of human beings, both ancient and modern, Chinese and foreign. At present, the 400Gbit S system has been put into commercial use.

The loss of optical fibers is extremely low, and at the vicinity of the wavelength of light, the loss of quartz fiber can be lower, which is lower than the loss of any current transmission medium. As a result, the transmission distance without a relay can be several times.

10. Even hundreds of kilometers. (2) Small signal crosstalk and good confidentiality performance; (3) Anti-electromagnetic interference, good transmission quality, electrical communication can not solve all kinds of electromagnetic interference problems, only optical fiber communication is not subject to all kinds of electromagnetic interference. (4) The optical fiber is small in size and light in weight, which is easy to lay and transport; (5) The material is abundant, and the environmental slag is well protected, which is conducive to saving non-ferrous metal copper.

6) No radiation, difficult to eavesdrop, because the light waves transmitted by the optical fiber cannot escape outside the optical fiber. (7) The optical cable has strong adaptability and long life.

Optical fiber communication has many advantages: it has a large transmission frequency bandwidth and communication capacity; Low transmission loss and long relay distance; The wire diameter is thin, the weight is light, and the raw material is quartz, which saves metal materials and is conducive to the rational use of resources; Strong insulation and anti-electromagnetic interference performance; It also has the advantages of strong corrosion resistance, strong radiation resistance, good turnability, no electric sparks, small leakage, strong confidentiality, etc., and can be used in special environments or military.

The principle of optical fiber communication is: at the sending end, the transmitted information (such as voice) must first be turned into a telecommunication slot, and then modulated to the laser beam emitted by the laser, and the number and intensity of the light change with the amplitude (frequency) of the electrical signal, and send it out through the optical fiber; At the receiving end, the detector receives the optical signal and converts it into an electrical signal, which is demodulated and restored to the original information

With the increasing speed of information technology transmission, optical fiber technology has been widely valued and applied. In the multi-microcomputer elevator system, the application of optical fiber fully meets the requirements of correct, reliable and high-speed transmission and processing of a large number of data communications. The application of optical fiber technology in elevators has greatly improved the response speed of the entire control system, and the parallel group control performance of the elevator system has been significantly improved.

The optical fiber communication device used in the elevator is mainly composed of a light source, a photoelectric receiver and an optical fiber. and chop.

Categories: Education Science.

Analysis: A simple definition of optical fiber.

Fiber optics are a medium that transmits information from one end to the other. It is a piece of glass or plastic fiber, which is used as a transmission medium for the passage of information. _

Usually the terms "optical fiber" and "fiber optic cable" are confused. Most optical fibers must be covered by several layers of protective structure before use, and the cable after the wrapping is called a fiber optic cableThe protective structure of the outer layer of the optical fiber can prevent the surrounding environment from harming the optical fiber, such as water, fire, electric shock, etc.

Characteristics of optical fibers.

Since optical fiber is a transmission medium, it can be like a general copper cable, transmitting information such as ** call or key computer data, the difference is that optical fiber transmits optical signals instead of telecommunication signals. As a result, fiber optics have a lot of unique advantages.

For example: broadband bandwidth. Low loss. Shielding against electromagnetic radiationLightweightSecurity. Privacy.

Operation of the fibre optic system.

You may know that the process of any communication transmission includes: encoding, transmission, decoding, and of course, the transmission process of fiber optic systems is also about the same. After the electronic signal is input, the signal is digitally encoded through the transmitter to become an optical signal, and the light is transmitted to the receiver at the other end through the optical fiber, and the receiver then decodes the signal and restores it to the original electronic signal output.

Optical fiber is an abbreviation for optical fiber, which is a fiber made of glass or plastic that acts as a light conduction tool. The transmission principle is to use the total reflection of light to transmit optical signals on optical fibers.

Light travels at different speeds in different substances, so when light is emitted from one substance to another, it is refracted and reflected at the interface of the two substances. Moreover, the angle of the refracted light will change with the angle of the incident light. When the angle of the incident light reaches or exceeds a certain angle, the refracted light disappears and all the incident light is reflected back, which is the total reflection of light.

Different substances have different angles of refraction of light of the same wavelength (i.e., different substances have different refractive indexes of light), and the same substances have different angles of refraction of light of different wavelengths. Optical fiber communication is based on the above principles.