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Liquid Crystal Display (LCD)

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Liquid Crystal Display (LCD)

  • LCD stands for Liquid Crystal Display.
  • It is a flat panel electronic display device which uses light modulating properties of liquid crystal.
  • LCD are raster format display.
  • LCD is made from electronic circuit, mirror, liquid crystal layer, positive and negative electrodes, polarizing films, TFT glass, glass cover etc.
  • TFT (thin film transistor) glass consists of many TFT’s.
  • LCD consists of large number of small pixels.
  • Pixels are in between two electrodes one is positive and second is negative electrode.
  • When no voltage is applied then liquid crystals are in random form or twisted form and when voltage is applied then they come in strengthen form.
  • Each pixel is consist of 3 colour i.e. red, green and blue (RGB).
  • Many pixels form a object using different intensities of colour of RGB.
  • LCD are use for computer monitor, television, watches, mobile phone, and other display devices.
  • LCD uses polarization of light and electric field to display objects.
  • There are two types of LCD one is active pixel display and second is passive pixel display.
  • Active pixel display consists of switch at each pixel and passive pixel display do not consist of switch at each pixel.


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