LCD screens are exceptionally modern in style, and the liquid crystals that make them work have allowed humanity to create thinner, more portable technology than we’ve ever had access to before. From your wristwatch to your laptop, many of the electronic devices we transport from place to place are only possible because of their thin and light LCD screens. Liquid crystal display (LCD) technology still has some obstacles in its way that can make it unreliable at times, but overall, the invention of the LCD has enabled great strides in global technological progress.
Although liquid crystals are not really liquid, their molecules behave more like a liquid than a solid, which earned them their name. The crystals in an LCD screen exist in a kind of unique middle ground between the solid form and the liquid form, which gives them the movement and flexibility of a liquid; but you can also leave them in place, as a solid. Heat can quickly melt a solid into a liquid, allowing it to move, while cold will cause the liquid to solidify almost instantly. The sensitivity of liquid crystals to temperature can be an advantage or a disadvantage. It enables the highly successful use of liquid crystals in devices like thermometers, where the response to temperature is a boon; But unfortunately, this very property can make LCD screens unreliable in extreme climates.
In an LCD screen, electrical currents work at a microscopic level to control the amount of light that passes through the liquid crystal molecules that make up the screen’s moving layer, which is sandwiched between panels of clear glass. Currents can force naturally twisted molecules to unwind or twist further, thereby changing the amount of light that can pass from the bulb behind the glass to the viewer’s eye. You can help him understand this process by imagining that light filters through an LCD screen in the same way that sunlight filters through the leaves of a tree. Now imagine that the tree is being blown away by the wind and you will see that the amount and location of the light entering through the leaves changes. This is very similar to the dynamics that powers an LCD screen, except that the sun is a small light bulb, the leaves are liquid crystal molecules, and the wind is made up of electrical currents sent by the computer and designed to create a pattern of light that your eye will interpret as words or pictures.