What are the detailed parameters of the optical module

What are the detailed parameters of the optical module? Optical module center wavelength, transmission distance, loss and dispersion, laser type, fiber interface, etc. Let’s take a look below!

Optical module parameters

Center wavelength: the unit of center wavelength is nanometer (nm), currently there are three main types:

1) 850nm (MM, multi-mode, low cost but short transmission distance, generally only 500m);

2) 1310nm (SM, single mode, large loss but small dispersion during transmission, generally used for transmission within 40km);

3) 1550nm (SM, single mode, small loss but large dispersion during transmission, generally used for long-distance transmission of more than 40km, and can directly transmit 120km without a relay).

Transmission distance: Transmission distance refers to the distance that optical signals can be directly transmitted without relay amplification, and the unit is kilometers (also called kilometers, km). Optical modules generally have the following specifications: multi-mode 550m, single-mode 15km, 40km, 80km and 120km and so on.

Loss and dispersion: the two mainly affect the transmission distance of the optical module. Generally, the link loss is calculated at 0.35dBm/km for the 1310nm optical module, and 0.20dBm/km for the 1550nm optical module. The calculation of the dispersion value is very complicated , generally only for reference;

Loss and dispersion: These two parameters are mainly used to define the transmission distance of the product, and the optical transmission power and receiving sensitivity of optical modules with different wavelengths, transmission rates and transmission distances will be different;

Laser category: At present, FP and DFB are the most commonly used lasers. The semiconductor materials and resonator structures of the two are different. DFB lasers are expensive and are mostly used for optical modules with transmission distances greater than 40km; FP lasers are cheap and generally It is used for optical modules whose transmission distance is within 40km.

Optical fiber interface: SFP optical modules are all LC interfaces, GBIC optical modules are all SC interfaces, and other interfaces include FC and ST;

The service life of the optical module: the international unified standard, 7×24 hours of uninterrupted work for 50,000 hours (equivalent to 5 years);

Working environment: working temperature: 0~+70℃; storage temperature: -45~+80℃; working voltage: 3.3V; working level: TTL.