However, for wider incidence angles "α" some light may be lost, as shown on the right.
Non-normal incidence angles also usually cause the reflection to be polarization dependent.
Each incidence angle corresponds with a single lift-drag pair.
The goal of the sailor is to set the sail in the incidence angle where the pressure is maximum.
The effect is also more pronounced for higher incidence angles (angles farther from the normal).
But I'll bet you're seeing an oval smear across our bow, and from that you can compute the incidence angle.
The scanning is cross-track, up to an incidence angle of 50 .
Spectralon can partially depolarize the light it reflects, but this effect decreases at high incidence angles.
By varying the incidence angle the various contributions can be identified.
At other incidence angles the reflectivity will also depend on the polarization of the incoming light.