Attenuation in an optical fiber occurs as a result of the way the light interacts with the structure of the fiber both at a microscopic and a macroscopic level. It is one of the parameters that can be affected by the processes used to manufacture the fiber and the cable.
All the intrinsic and extrinsic mechanisms that create this loss of signal are known to be wavelength dependent and as such are normally measured over the useable spectrum for which the fiber is designed,hence the term 'Spectral Attenuation' is used.
Exposure of the fiber to Hydrogen has the potential to slightly increase the attenuation caused by absorption across the spectrum but with certain wavelengths, this additional attenuation can be significantly greater.
Measurement of the attenuation at these more sensitive wavelengths before and after exposure to Hydrogen will yield a good measure of how well the fiber is protected from such effects.
The 'Production/Lab/R&D' range is suitable for manufacturers of fiber and cables where this in process test is usually performed..