How to Reduce Glare off Water by Factor of 1.33: Polarization Physics Problem

[sachi]

"by what factor may the glare off water be reduced when the sun is at

a) 45 degrees above the horizon
b)60 degrees above the horizon

n.b refractive index of water is 1.33"

I have derived the fresnel reflection coefficients for the cases when E is perpendicular to the plane of incidence, and when E is parallel to the plane of incidence. I am also assuming that "glare" is caused by the E-field. But I'm not sure which reflection coeffient to use i.e do we assume that E is parallel to plane of incidence of perp.?

thanks

 

[Meir Achuz]

The E field from the blue sky is predominantly horizontally polarized.
This is because the Rayleigh scattering polarizes the scattered radiation.
The horizontal polarization comes out to be
P=sin^2\theta/(1+cos\theta)^2.
You will have to use both E polarizations at the water surface.
The above factor gives the polarized horizontal E^2. Then you have to include both E polarizations with E^2 = one half of the unpolarized component.