https://doi.org/10.1351/goldbook.08673
Reflection-absorption with very thin layers of an absorbing material on a metallic substrate and the angle of incidence between
Note:
As the incident radiation beam travels nearly parallel to the sample surface, the electric vector of the radiation is then either parallel or nearly perpendicular to the surface.
As the incident radiation beam travels nearly parallel to the sample surface, the electric vector of the radiation is then either parallel or nearly perpendicular to the surface.