LCD displays have been around for years in everything from cell phone screens to computer displays. Like a plasma display they are made of two pieces of glass-like material with liquid crystals sandwiched in between the pieces of polarized glass. LCD displays are often called trans missive displays because the liquid crystals do not actually create the light needed to display the images but actually control the light and the amount of light coming from the display. Basically the display works on the principal of blocking light emission. Depending on the amount of voltage placed through liquid crystal they can control the amount of light that passes through the liquid. The liquid crystal cannot create their own light so an external light source is necessary and this is in the form of a special fluorescent light bulb. This bulb placed behind the LCD panel and the light from the bulb is diffused by a white diffusion panel so that the amount of light emitted onto th e LCD is uniform. The liquid crystals will control the amount of light that passes through the glass panels and the inner working of pixels and sub pixels to form images and control color. The LCD pixels act like tiny shutters that either open or close to let light in or to block the light..
LCD displays can be made very thin. Since no phosphors are burned like in traditional CRT television and Plasma displays and the liquid crystals do not produce the light but rely on a back light; no radiation is emitted from the screen. Plasma and CRT screens emit low levels of radiation. Another plus side to not having to burn off phosphors to produce images LCD televisions use less electricity than Plasma's and CRT's do.
Viewing angles used to be an issue with LCD displays. The early LCD display where originally designed to be computer monitors thus meant to be viewed straight on. Recent improvements have given the newer LCD's better viewing angles than mo st Plasma's measuring in a 170 degrees on the high end models.
PRO'S
Very thin displays can be made. Makes LCD television a great space saver.
Very little electricity is used when compared to Plasma and CRT televisions.
Sharp images can be produced
Life span is longer than plasma. Some displays are rated up to 80,000 viewing hours by the maufacturer's
Back light bulbs can be replaced in some screens
Do not suffer from image burn-in
Can double as computer displays.
CON'S
More expensive than Plasma and rear-projection per square viewing inch
Screen sizes aren't up to Plasma displays yet (current sizes range from 10 to 45)
Colors are not as vibrant as plasma displays and blacks and grays are not as deep and well defined as on a Plasma television.
Motion trails (pixelation) with moving images
Viewing angles are reduced at about 20 degrees off center. Note that this problem has been fixed on m any of the newer displays.
Bill Ransom provides the latest information reviews of Plasma, LCD and Rear Projection HDTV Television at http://flatscreenbuyers.com
Author:: Bill Ransom
Keywords:: LCD, LCD displays, LCD televisions, LCD Hdtv, Hdtv, Lcd pros, Lcd cons
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