Technical data

www.westermo.com Theoretical and general applications 49
Attenuation in singlemode fibre
A singlemode fibre has such a fine core that it can only support one mode, which
means that the transmitted light pulse is not distorted whilst travelling through the
cable.
Wave length
The attenuation in a cable is also dependent on the wavelength of the light produced
by the transmitter. Wavelengths with low attenuation are 820 nm, 1300 nm and
1550 nm. Singlemode fibres will only effectively propagate the higher frequencies.
Transmitted
light pulse
Light path in singlemode fibre Received
light pulse
B A C K