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Re: POLARIZATION

David seemingly had some difficulty with my classification of 'left hand'
and right hand' polarizations of EM waves.
Nevertheless, that's how it is!

And at below VHF on up through light frequencies, it is quite rational to
describe a circular ( properly helical) polarization as a quarter wave
displacement of orthogonal components, as he does.

But perhaps David has forgotten that the sense of the quarter wave
displacement (advanced or retarded) determines the handedness of such
electromagnetic waves.

Brian Whatcott Altus OK


At 15:18 6/4/98 EDT, David wrote:
You are making circular polarization much more complicated than it really is.
Let me quote from An Introduction to the Methods of optical
Crystallography by
Donald Bloss. "If the path difference between the two waves emergent from a
crystal is lambda/4 (or any odd multiple of lamda/4) their vibrations
interfere
where they coincide in space and time, to produce resultant vibration vectors
of constant lengths but variable azimuths..." There is no need to invoke
handedness or corkscrew paths. ...

On Fri, 29 May 1998 10:09:12 -0500 brian whatcott said:
It is not difficult to configure an array of dipoles, yagi style, so that
the polarization angle is changed. Just a matter of geometry of conductors.

In stereo chemistry, stereoactive materials are classified as
configurational, geometric and conformational isomers which involve either
chirality (handedness, or non superimposability of a mirror-image) or
rotation of some part of a molecule round a double or single bond.
...
Brian Whatcott Altus OK