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Polarized Light


What exactly is polarized light? You may have heard of it before, or read the name. It sounds cool, so what is it? That is what I will explain in this post.

Light is like a wave, or bumpy curve, in many respects. This wave is a sine wave (see my Sine and Cosine post). The wave can oscillate (wobble) in an up-down motion, or a left-right motion; sometimes it does a mixture of both, and wobbles in a circular pattern.

Look at the wall, or the floor. There are quadrillions of light waves bouncing off them. Some of the light waves oscillate in an up-down motion, others oscillate in a left-right motion, and others oscillate in a diagonal motion. The different types of waves are all jumbled together. Is it possible to have a bunch of light waves that all wobble the same way? Yes! Light like that even has a name: polarized light.

You can buy filters that will polarize light; the filters are called polarizers, or polarized filters. Some sunglasses are made with polarized lenses; those are called polarized sunglasses.

There are many uses for polarizers and polarized light. I will discuss some of these uses in later posts.

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