The substance that is central to making a flat-panel work is liquid crystal placed between crossed polarizers. The liquid crystal changes alignment when a voltage is applied and is controlled by an array of thin-film transistors, the active matrix. In the case of a flat-panel display, if voltage is applied to the liquid crystal, the crystal changes alignment, and the light is unable to pass through the polarizer. On the other hand, when no voltage is applied to the liquid crystal, light is able to be seen. This is what enables the picture you see. |
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