I just bought an iPad mirror screen protector and I'm really puzzled about how it works.
You can see a video of the protector here
The mirror quality is very good, of the order of 95% reflectivity, and it's not a metalized film as transmission is ~95%
You can see in the video that there is a diffraction type of coloring at grazing angles.
If I rotate it in front of an LCD screen there is a weak polarization effect.
The manufacturer claims it comprises three layers but doesn't explain the physics.
What is going on?