NON-circular polarizer for lenses?

You're not missing much.

When you have a molecular compound and the molecules don't have a center of symmetry, you have two different kinds of molecules which are reflections of each other. Both have the same molecular mass, boiling and melting points, but they are like your hands - similar but non superimposable. If you separate the two kinds of molecules, each may rotate polarized light in a solution. One will rotate it clockwise - the other counterclockwise.

That's pretty much left/right-hand-polarization.

I was not referring to molecular compounds. I was referring to electromagnetic radiation.

---Bob Gross---

Yes, but it's the physical medium that imparts the circular (RH or LH) polarization to the EMR passing through.

I guess that depends on your point of view. Microwave transmitters can employ a RH or LH circularly polarized antenna/waveguide to ship a signal through a near-empty medium. So, I don't think there is anything in the molecular makeup of the antenna that is doing it, it is the physical design of the antenna that is doing it.

Microwave energy is just sort of "slow light."

---Bob Gross---

I'll point out that it's still the physical medium which is responsible for the polarization, which is what I said. In the case of light, passing through a polarizing medium can filter out one component of the radiation; passing a component of that through a quarter-wave plate can impart a phase shift. It's been about the same 35 years since I first studied polarized light (in optical crystallography). In the case of an antenna, use of a 1/4 wave retarding component in the antenna will result in the circular polarization.

Georgia State University Physics Department has an illustrated explanation...

http://hyperphysics.ph​y-astr.gsu.edu/hbase/phy​opt/polclas.html