Liquid crystals are a kind of matter that exists somewhere between a liquid and a solid. We can control the order of the liquid crystals used in liquid crystal displays with electricity. Think of it like a valve for light. We can open and close the valve by changing the alignment of the liquid crystals using electrical fields.

Originally released by National Science Foundation, 2011. Streaming video file encoded with permission for digital streaming by Infobase on May 05, 2015.

Liquid Crystals: Chalk Talk (2:00); .