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| Operation |  Liquid crystal displays are rather widespread and most people couldn't get through their day without using one. This technology is used in digital clocks, microwave ovens, calculators, stereos, thermometers. Liquid crystal technology has influence the appearance of slim, cool-looking, bright displays which can be seen everywhere.
The most common type of liquid crystal being used in display applications today is the twisted nematic (TN) liquid crystal. Its structure is naturally twisted. The crystal reacts to electric currents in predictable ways.
The principle of LCD monitor’s work is based on blocking light. It is possible to manipulate the intensity of light which passes through this crystalline matrix and out the glass panel at the other end. Electrical charge run through liquid crystals, they untwist so that the intensity of light able to pass through the second polarized pane is affected. Basically, these displays can switch between light states (where the liquid crystals are fully twisted) and dark states (where the liquid crystals are fully untwisted), or somewhere along the gray scale in between.
A liquid crystal display consists of an array of small segments-called "pixels"-that are arranged to form images or to present information. Pixels are turned on and off so as to create an image on the polarized display pane in front of you. This process is known as addressing. So-called active-matrix LCD TVs employ thin film transistors (TFTs), or small switching transistors and capacitors arranged in a matrix on a glass substrate, to direct electric charges down columns to reach a particular pixel. This, in turn, causes the liquid crystals to untwist and "display" a predetermined amount of light generated by the light source-usually a florescent bulb-in back of them.
Florescent bulb is the light source in an active-matrix LCD monitor. Florescent bulb gives off white light through a polarized glass pane behind the liquid crystal solution. Liquid crystals of white display are completely twisted and therefore able to direct the full spectrum of light out through the polarized display screen in front of you. It is possible to manipulate the full spectrum of light to produce the desired color, because all wavelengths can pass through. Each pixel is divided into three subpixels - red, green, and blue. They work in conjunction to determine the LCD pixel's overall hue. These subpixels are created by subtracting certain wavelengths, and the color corresponding thereto, using special filters. By exploiting a combination of red, green, and blue subpixels of various intensities (or gray scales), a single pixel triad can reproduce approximately 16.8 million colors.
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