also known as a liquid crystal display. It is used in our everyday lives in things all around us. It is a a thin, flat display device made up of any number of colour or monochrome pixels arrayed in front of a light source or reflector . It uses very small amounts of electric power, and is therefore suitable for use in batterypowered electronic devices. LCD displays are used in laptop computers, digital clocks, watches, microwave ovens, CD players and many other electrical devices. They are very common because they have several advantages such as being thinner and lighter and draw much less power than cathode ray tubes (CRTs).
external image LCDProjectorworks.gif
external image LCDProjectorworks.gif

In color LCDs each individual pixel is divided into three cells, or subpixels, which are coloured red, green, and blue, respectively, by additional filters (pigment filters, dye filters and metal oxide filters). Each subpixel can be controlled independently to join thousands or millions of possible colors for each pixel.

This is an image of how a colour LCD display magnifys from colours to images.

Important factors to consider when evaluating an LCD monitor:
  • Resolution : The degree of sharpness of a computer. The number of pixels across and down on a display screen. The horizontal and vertical size expressed in pixels (e.g., 1024x768).
  • Dot pitch : The distance between the centers of two adjacent pixels. The dot pitch rating of a monitor tells you just how sharp the displayed image will be. The smaller the dot pitch size, the less grain is present, resulting a sharper image. Dot pitch may be the same both vertically and horizontally, or different (less common).
  • Viewable size: The size of an LCD panel measured on the diagonal. This is the viewing of the images being displayed.
  • Response time : The minimum time it takes to pass while waiting for a computer to respond to a command and the time necessary to change a pixel's colour or brightness.
  • Matrix type : Active or Passive.
  • Viewing angle : also known as viewing direction . It is the angle of which the monitor is viewed.
  • Colour support: How many types of colors are supported ( more specifically known as color gamut ).
  • Brightness : The amount of light emitted from the display (more specifically known as luminance ).
  • Contrast ratio : The ratio of the intensity of the brightest bright to the darkest dark.
  • Aspect ratio : The ratio of the width to the height (for example, 4:3, 16:9 or 16:10).
  • Input ports (e.g., DVI , VGA , LVDS , or even S-Video and HDMI ).

LCD panels have gained popularity for a number of years now, by contrast, CRT displays have begun to disappear from the users’ desks. Today LCD displays offer acceptable levels of quality, but require less power and desk space. Today manufacturers of monitors are looking forward different technologies to make LCDs even better. One of such technologies is Organic Light Emitting Display (OLED) which has its positives and its negatives, but eventually may become the replacement for current liquid crystal displays.
“For conventional displays, OLED will offer a better, clearer picture and lower power consumption. OLED technology will spread far; it will make new displays into previously undeveloped markets. We will see the emergence of transparent and flexible displays. Transparent displays may finally bring out a useful wearable PC. They should look a lot like the ones that appear in movies. They should be as transparent as glass or plastic. Flexible displays will also come out in the future. These will be mostly used in mobile devices because they offer a smaller size and are more durable. There will be a few other applications for this flexible display that will use the flexibility of the display,”

Unlike a CRT monitor, plasma display, or LCD monitor, the OLED uses emissive technology. This means that the screen itself emits light, and therefore doesn't require additional hardware for creating light, like tubes or lamps. Less hardware means less bulk. In fact, the screen could be as thin as a piece of paper. Today you can find some OLED technology in cell phones, PDAs, and car stereos. In a few years, you may find OLED technology on laptop computers, car instrument panels, and perhaps even a portable presentation device that can be easily rolled up and stowed away. The images below are of displays that are using OLED technology. Its amazing how thin they are!

LCD displays are the most commonly found displays found in todays society. They vary in price depending on the brand, model, features and also display size. A 17" LCD display may vary form $240.00-$270.00. A 19" LCD display may vary from $250.00- $400.00. From 22" and up they can go from about $500.00 to a couple of thousand.