Through the understanding of optical fiber, we understand that optical fiber transmits signals through light guide, is not conductive, and is not afraid of lightning strikes, so it does not need grounding protection. According to the transmission mode of light in optical fiber, it is divided into: multi-mode fiber and single-mode fiber optical fiber. For our users, you can remember the origin of the multimode and singlemode names.
1. Multi-mode fiber modules and single-mode fiber modules
Multimode fiber module: Can transmit multiple modes of light.
Single-mode fiber modules: Only one mode of light can be transmitted.
The transmission distance of multi-mode fiber modules is relatively short, and usually the transmission distance of single-mode fiber modules can reach dozens of times that of multi-mode fibers. The price of single-mode fiber is generally more expensive than that of multi-mode fiber.
1. When the information point transmission distance is greater than 100m, if you choose to use copper cable. Repeaters must be added or network equipment and weak current rooms must be added, thereby increasing costs and hidden troubles. The use of fiber optic modules can easily solve this problem.
2. There are a large number of electromagnetic interference sources in specific working environments (such as factories, hospitals, air-conditioning computer rooms, power computer rooms, etc.), and optical fibers can be free from electromagnetic interference and operate stably in these environments.
3. There is no electromagnetic leakage in the fiber optic module, and it is very difficult to detect the signal transmitted in the fiber optic module. It is a good choice in places with high confidentiality requirements (such as military, R&D, auditing, government and other industries).
4. In environments with high bandwidth requirements, reaching more than 1G, fiber optic modules are a good choice.
In the actual application process, single-mode fiber is used if the distance is long; multi-mode fiber can be used if the distance is short, and optical modules are required for optical fiber transmission. Optical modules, generally the price of single-mode optical modules is higher than that of multi-mode optical modules.
1. What is the difference between single-mode fiber and multi-mode fiber?
Single-mode fiber uses solid-state laser as light source; multi-mode fiber uses light-emitting diode as light source; single-mode fiber has a long transmission frequency bandwidth and long transmission distance, but because it requires a laser source, the cost is high;
Multimode fiber has low transmission speed and short distance, but its cost is relatively low; single-mode fiber has a small core diameter and dispersion, allowing only one mode of transmission; multi-mode fiber has a large core diameter and dispersion, allowing hundreds of modes to transmit.
2. What is the difference between a single-mode optical module and a multi-mode optical module?
The working wavelength of the multi-mode optical module is 850nm; the working wavelength of the single-mode dual-fiber optical module is generally 1310nm and 1550nm;
The devices used in single-mode optical modules are twice that of multi-mode optical modules, so the overall cost of single-mode optical modules is much higher than that of multi-mode optical modules; the transmission distance of single-mode optical modules can reach 160km; The transmission distance of multimode optical modules can reach 2km.
3. Can multi-mode fiber be used with single-mode optical module?
First of all, the multi-mode and single-mode converters must have corresponding wavelengths and optical transceiver functions to achieve photoelectric conversion. Secondly, the core diameters of single-mode fibers and multi-mode fibers are very different, which will cause the insertion loss to be too large when the two are matched. Mode fibers can be used with single-mode optical modules, but the use effect cannot be guaranteed.