Optical module is a device for receiving light-emitting signal in optical fiber transmission system, which is used to connect two electric port devices (such as servers, switches, etc.) together with optical fiber. According to different types of applicable optical fiber, optical modules can be divided into single-mode optical module and multi-mode optical module.
About single-mode and multi-mode optical modules
As the name implies, single-mode optical module is the optical module used together with single-mode optical fiber. Using LD or LED with narrow spectral line as the light source, it can transmit data signals with extremely high bandwidth, so the transmission distance is very long. And the multimode optical module is used with multimode fiber, with LED or laser as the light source, and the transmission distance is short.
Difference between single mode optical module and multimode optical module
The differences between single-mode optical module and multi-mode optical module are listed in detail as follows:
Transmission rate and distance - both single-mode and multi-mode optical modules can support 10g and 40g transmission, but the transmission distance is quite different. The maximum transmission distance of multimode optical module is about 550 m, while that of single-mode optical module can reach 10 km, 40 km, 80 km or more.
Price - single mode modules use twice as many devices as multimode modules, so they are slightly more expensive than multimode modules.
Performance - generally speaking, single-mode optical module can only be used with single-mode fiber, and multimode optical module can only be used with multimode fiber, not mixed.
Power consumption - the power consumption of a multimode optical module is less than that of a single-mode optical module.
Tips for using single mode / multimode optical modules
When using single-mode / multimode optical modules, the following points should be noted:
Ensure that the optical modules at both ends of the optical fiber link work at the same wavelength; in order to reduce the packet loss rate of data, the short-distance transmission application uses multimode optical modules, and the long-distance transmission application uses single-mode optical modules; do not bend the optical cable between the refraction modules to prevent excessive loss of optical fiber.