LCD
How it's works?
LCD stands for liquid crystal display. LCD screens first became popular as computer monitors before being adapted as televisions. The screen consists of two sheets of polarized glass; sandwiched between these is a solution made of liquid crystals. The glass is back-lit by a fluorescent bulb.When electrical current flows through the liquid, the crystals move, and the polarized glass allows certain wavelengths of light from the bulb to pass through. This creates thousands of tiny dots, or pixels, of color that ultimately make up the picture on an LCD TV.
LCD TVs are a good choice for people looking for an affordable HDTV. They have a much better picture quality than old-fashioned CRT televisions, and they’re relatively light-weight. They’re also ideal for watching television in any light condition; they work equally well in dark or well-lit rooms.
Drawbacks
One problem that some people have with LCD technology is that it is limited when compared to other types of HDTVs. The display has a low contrast ratio, and there is no way to get “true” black on the screen. This leads to LCD TVs having a slightly washed-out look that some people do not like.
Plasma
How it's works?Plasma TVs were developed in response to the weaknesses of LCD displays. Like LCD displays, a plasma screen TV has two panes of glass that make up the flat screen. Rather than using liquid crystals, plasma TVs have chambers filled with xenon and neon. When electricity runs through these chambers, the gas converts into plasma; as the plasma moves through the chamber, it emits photons that display in various colors.
Plasma televisions have excellent picture quality. The colors are very sharp and precise thanks to the reaction of gases, and the televisions also display very deep blacks. The screen can sometimes experience a “color burn” if they get a lot of use. When the television is turned off, a shadow of images may stay on the screen, and the color may be slightly faded in the areas that are burned.Nevertheless, a plasma TV should last for approximately 60,000 hours of viewing time, which should offer ample life for most television viewers. Plasma TVs use less electricity than traditional CRTs, but they do have a slightly higher power draw than those using LCD or LED technology.
Drawbacks
One of the primary drawbacks of plasma technology is its cost. These TVs are somewhat heavier than others of their kind, and they cost more to produce due to the use of noble gases. They are also prohibitively expensive to repair and sometimes cannot be repaired at all. Plasma TVs also look much better in low light than in bright light.
LED
How it's works?
The newest type of HDTV on the market uses LED technology. Similar to an LCD display, an LED screen utilizes a liquid crystal display sandwiched between two sheets of polarized glass. Rather than using a fluorescent back-light to illuminate the picture, however, LED screens use light emitting diodes. This makes LEDs more energy efficient and greatly improves picture quality.
Benefit
LED TVs have better color contrast and brightness than either plasma or LCD displays. Blacks are deep and rich rather than seeming washed out, and the display is bright enough to watch in any light. They also draw less power than either LCD or plasma displays, and the energy efficiency helps to compensate for the technology’s fairly high cost.
Drawbacks
The greatest drawback of an LED TV is its cost. Because the technology is new, it is more expensive than its competition. Additionally, LED TVs still sometimes suffer from the “dead pixel” issue that haunts LCD screens.
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