OFC

 SM fibre ( Single mode fibre)-

It is a type of fibre optics cable that has smaller core diameter compared to multimode fibre.

This means only a single mode of light can travel through it,resulting less signal loss and higher bandwidth.

It transmits a single ray of light,which has higher bandwidth capabilities and preferred in longer distance applications.

Multi mode Fibre Optic Cable-

Large diameter core that allows multiple modes of light to propogate.

As the core increases,more data passes through a given time.

Quality of signal reduced over long distances.

Typically used for short distances,data and audio/video applications in LANs.

Windows of OFC -

1 st window - 850 nm - Short wavelength region

2 nd window - 1310 nm - O band

3rd window - 1550 nm - C band

Attenuation is minimum at 3 rd window.

2nd and 3rd window are used in Single Mode Fibre.

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