This part of IEC 61757 is a generic specification covering optical fibres, components and sub-assemblies as they pertain specifically to sensing applications, in those aspects not already addressed by previous or concurrent standardization efforts.
A fibre optic sensor contains an optical or optically powered sensing element in which the information is created by reaction of light to a measurand. The sensing element can be the fibre itself or an optically powered element inserted along the optical path. In a fibre optic sensor, one or more light parameters are directly or indirectly modified by the measurand somewhere in the optical path, contrary to an optical data link where the information is merely transmitted from the transmitter to the receiver.
The object of this generic specification is to define, classify and provide the framework for specifying fibre optic sensors, and their specific components and subassemblies. Fibre optic sensors are devices for extracting information from the environment using fibre optic technology.