A site with a very nice history of polarization: http://www.polarization.com/history/history.html
The story of polarization begins with "birefringence",
a property of some crystals to produce double images.
It indicates the presence of two types of light rays,
each one with a different *linear* polarization.
Some of the ways of separating one *linear* polarization from the other:
- by reflection (from flat glass or water, for example)
- by scattering (as in the atmosphere, or through milky water)
- by double refraction and redirection of one ray (compound calcite prism)
- by double refraction and absorption of one ray (dichroism, polaroid film)
- by laser action. Laser light is already monochromatic and in phase.
In many lasers it is also polarized (naturally or artificially).
There are 2 states of light and this is what gives rise to "polarization".
What s the origin of these two states and why are there only two ?
How do these states mix and how can they be measured?
- linear polarization
- circular polarization
Many organic compounds can distinguish the two forms of *circular* polarization of light.
- chiral molecules
- chirality in organic compounds, most (all?) organic amino acids are l-chiral (laevus, left) and many (most?) organic sugars are d-chiral (dexter, right).
Some sugars.
Examples and experiments ...
More advanced: The Illinois Mach-Zender interferometer, (copy). How to use the two level property of light (polarization!) and the quantum Zeno effect to achieve interaction free measurement, most of the time.
More advanced: weak force The weak force is known to be fundamentally "polarized". Can this polarization affect electromagnetic radiation (light!)?