To avoid losses in the transmittivity
the grating height has to be large enough to include the illuminated area which could increase up to 5 or 6 times with respect to normal incidence.
, T, reflectivity, R, and absorptivity, A can be calculated using Eqs.
The mode coupling between the two fiber cores is sensitive to the pressure-induced index change, which provides a one-to-one correspondence (within a half period) between the force and the transmittivity
of one core into which the broadband light is injected.
Most of the transmittivity
problems encountered in radome materials are caused by the reflection of RF energy at the interface of two materials having different dielectric constants.