scope:

Applies to the family of fibre optic filters. These components have all of the following general features:-they are passive for the reason that they contain no optoelectronic or other transducing elements which can process the optical signal launched into the input port;-they modify the spectral intensity distribution in order to select some wavelength and inhibit others;-they are fixed, i.e. the modification of the spectral intensity distribution is fixed and can not be tuned;-they have a maximum of two ports for the transmission of optical power,- the ports are optical fibre or optical fibre connectors;-they doffer according to their characteristics.