Re: [Leica] The Polarizer Problem

[Paul and Paula Butzi <butzi@halcyon.com>]

At 03:50 PM 6/10/98 , Dan Cardish wrote:
>>
>>A circular polarised filter is simply a linear pol to filter
>>the light based on the polarization, followed by a
>>1/4 wave plate, which randomizes the polarization of
>>the transmitted light.  [snip]
>
>not quite.
>
>The 1/4 wave plate delays one component of the electric field vector by
>90=BA, so that the resulting E vector rotates in space as it travels=
 forward,
>looking like a corkscrew.  Recall (?) that the electric field vector (and
>also the corresponding magnetic field vector B) are perpendicular to the
>direction of the light ray.  Some substances like calcite have differing
>indices of refraction (hence velocity of light) depending on which
>direction a light wave travels through it.  This can be used to make the
>1/4 wave plate which is placed after a regular polarizer (it is important
>to use a circular polarozer in the proper orientation).
>
>A very brief explanation, hope it makes sense!
>
>Dan C.
>=20

See?  I knew that nothing would provoke someone into posting
the *right* answer quite like posting one that's *nearly* right
would.

Thanks, Dan, for setting it straight.  (Time to crack out the
textbook, and review :-)

- -Paul