Phase shift for reflection at glass-metal interface in beam splitters

[naima]

I read this

No phase shift accompanies a rear surface reflection, since the medium behind the mirror (air) has a lower refractive index than the medium the light is traveling in (glass).

They do not talk about the metal between glass and air! Reflection occurs between glass (low index) and metal (high index)in the beam splitter. What about phase when metal is thick?

 

[UltrafastPED]

For more detail see: http://relativity.livingreviews.org/open?pubNo=lrr-2010-1&page=articlesu9.html

 

[naima]

Good link
look at Jones matrix
if we rotate the front surface by 180° it becomes a rear surface.
We have R(180) = R(-180) = -I
So the Jones matrix should remain unchanged.
Why is there a difference between the front reflection shift and the rear reflection shift?