Tiny liquid crystal molecules are sandwiched between the two polarizers, and these crystals can be switched by tiny transistors to act as light valves.

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And we, as consumers, face these sheer walls, smooth as glass, edifices of obsidian, crystal, and silver that reach up to the sky, blocking all but a tiny patch of light.

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They boast large global market shares in specialised niches: ceramics and other fine materials for semiconductors, tiny motors for hard drives and other digital equipment, a range of sophisticated machines for making liquid-crystal display panels, and so forth.

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Find this orientation by looking through the crystal at the sky at a time when you can see the sun, mark the sun's direction on the crystal, and your mark will always point towards the sun when you match the beams from even a tiny patch of blue in an otherwise overcast sky.

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