Dear Dr Saaed:

What is meant by Fresnel reflection?

The reflection of a portion of light resulting when light is incident upon the surface between materials that have different refractive indices. This Fresnel reflection depends upon the index difference and the angle of incidence.

Please take a look at the following useful links

https://www.youtube.com/watch?app=desktop&v=bX-k26w-tsU

https://www.brown.edu/research/labs/mittleman/sites/brown.edu.research.labs.mittleman/files/uploads/lecture13_0.pdf

Dear Dr Ijaz:

Thanks in advanced.

As you know when a wave have an oblique incidence with a plane, to calculate Fresnel reflection coefficient, the wave is decomposed into two S and P polarization (referred to "https://www.brown.edu/research/labs/mittleman/sites/brown.edu.research.labs.mittleman/files/uploads/lecture13_0.pdf" ) and then Fresnel reflection coefficient for each of S and P polarization is calculated separately. and I am seeking for a way to calculate the sum of these two reflection coefficients (note that we can not use arithmetic sum). because I need the overall reflection coefficient.

Dear Dr Abbas ; For oblique incidence have a look at the following useful links:

https://www.osapublishing.org/josaa/fulltext.cfm?uri=josaa-30-10-1975&id=261889

Article Optically ambidextrous circularly polarized reflection from ...

and most importantly:

https://www.ece.rutgers.edu/~orfanidi/ewa/ch07.pdf

Regards-