The nematic phase is the simplest form of liquid crystal and is the phase in which the crystal molecules have no orderly position and are free to move any which way. However, while they have no specific order, during this phase the molecules do tend to point in the same direction, which is what differentiates it from a pure liquid. Liquid crystal in this phase can be characterized by its thread-like appearance when looked at under a microscope. The use of nematic liquid crystal is common in telescope lenses as it allows for a clear image when researchers are confronted with atmospheric turbulence.
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