How do lcd screens work?

How Do LCD Flat Screens Work?

• Answer:

  The Basics of a LCD Flat Screen An LCD flat screen is simply a display screen that uses LCD technology to produce an image. This is done by using LCD shutters placed behind color filters. These LCD shutters open and close to let white light through to the filter. The white light is usually provided by a compact fluorescent bulb behind the screen. Each LCD shutter is very small and rests behind a color filter that is either red, green or blue. Each filter is considered a sub-pixel, while a set of all three filters (which are arranged in a line) form a single pixel of color. Each screen has thousands of pixels forming the entire image. LCD Technology LCD stands for liquid crystal display. The LCD shutters in an LCD screen consist of three parts: two polarizers (screens that block around half of the light going through them) and a nematic liquid crystal between them. The two polarizers are oriented at right angles to one another, so that they block 100 percent of the white light. The nematic liquid crystal is sandwiched between two directing plates. The directing plates have grooves in them, to which the nematic liquid aligns. These two directing plates direct the liquid in a twist that twists in approximately a 90 degree angle. This causes the liquid to resemble a prism that twists light in a 90 degree angle. Light must be oriented with the direction of a polarizer for it to pas through that polarizer. When half of the light from the bulb gets through the first polarizer, the nematic liquid crystal twists that light, which orients the light with the direction of the other polarizer, allowing the light to pass all the way through to the color filter. To close the shutter, an electric current is run through the liquid crystal, causing it to align with the current, which destroys the twist and allows the two polarizers to block the light coming through as if there were no liquid crystal between them. The Creation of an Image An image is created on the screen by a computer that tells certain shutters to close or open. This controls which color each pixel is and, hence, creates an image on the screen made up of all the pixels.