Re: polarization of reflected/refracted waves

[John Denker <jsd@MONMOUTH.COM>]

At 09:25 PM 9/26/99 -0500, Cliff Parker wrote:
>   What theory sheds light on why the angle between the
> plane of polarization and that of the reflected surface
> makes a difference in transmittance and reflection?

Polarization of reflected/refracted waves is well described by
 * classical wave mechanics in general
 * classical electromagnetism in particular

As an extreme example, check out the discussion of Brewster's angle in _The
Feynman Lectures on Physcs_ volume I at the top of page 33-6.

--------------

Feynman says "From Fig 33-4 it is clear that only oscillations normal to
the paper can radiate in the direction of reflection..." [in the Brewster
geometry].

To make this assertion extra-clear, keep in mind that you can either ...
 A) treat the medium as a macroscopic refractive substance, obeying
    Snell's law et cetera,  ...OR...
 B) treat the medium as a collection of microscopic re-radiators,
    obeying Maxwell's equations, from which Snell's law emerges as
    a consequence ...
 ... BUT NOT BOTH.

In particular, consider the waves re-radiated from atoms along the course
of the the transmitted beam.  These waves are not (!) bent by Snell's law
when they emerge from the surface, heading in the direction of the
reflected beam.  Remember, as soon as you mention re-radiators, you are
committed to the microscopic viewpoint.

______________________________________________________________
copyright (C) 1999 John S. Denker             jsd@monmouth.com