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Plasma TV Review

October 2nd, 2009 Joe Kingman No comments

The plasma television is a relatively new type of television, with a flat screen display. It works by having a mixture of different noble gases in small compartments behind a panel of glass. The plasma TV derives its name from the reaction in which these noble gases are turned into plasma, which emits light and forms the display you see. Plasma TV’s are often compared to LCD’s (liquid crystal displays), another type of flat screen television that uses liquid crystals in front of backlighting or fluorescent tubes to produce images.

Plasma televisions (and flat screen TVs in general) are extremely easy to handle. Due to their very nature, plasmas are flatter than traditional televisions (also called CRTs) and thus, are lighter as well. Currently averaging 5 inches in width and 100 pounds, their size will soon be reduced to an inch in width and 45 pounds. This lack of bulk has heralded in a new era of television placement; consumers can now mount their plasmas on the wall without worrying about ruining the wall.

Flat screen televisions cover a range of much higher resolutions than do traditional televisions. High definition plasmas and LCDs have resolutions from 1024×768 pixels per square inch to 1920×1080 pixels. The ceiling of resolution for CRTs stands at a mere 480 lines, providing a much more muddled picture than plasmas or LCDs do.

Plasma television manufacturers boast a lifetime of up to 60,000 hours for their televisions, compared to a CRT television’s life span of at least 5 years. Which is better? Depending on how much a plasma is turned on, its lifespan can range anywhere from 7 years (turned on for 24 hours a day, 7 days a week) to 55 years (turned on for 3 hours a day). The lifespan of a plasma TV is significantly greater than that of a CRT TV.

Plasma televisions have both a better color ratio and more contrast than LCDs. For plasma TVs, each pixel can virtually be turned off to produce truer blacks. However, LCDs use a backlight, which will shine through the “black” pixel and damage the contrast quality. CRT televisions have the best contrast, but both plasmas and LCDs surpass them when it comes to color reproduction.

The image of both LCDs and plasmas is comparable when viewed directly in front of the screen. However, plasma televisions have a wider viewing angle than their counterparts. Backlighting causes this problem in LCDs; the image on the screen degrades as the viewing angle increases. Plasmas can be viewed from the sides or top and bottom.

Many worry about the possibility of burn-in images on plasmas. This occurs when a still shot is shown on the screen for too long. Afterwards, a faint outline or trace of the image may still be visible on the plasma’s screen. However, this should not be a serious problem with newer models, as manufacturers have worked to eliminate the burn-in effect.

Plasmas also have virtually no size limitations; depending on a consumer’s budget, plasma screens can go up to any size. LCD and CRT televisions, on the other hand, are confined to approximately 40 inches diagonal.

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Everything You Should About LCD TVs

July 24th, 2009 Jack Stansfield No comments

For many years your biggest consideration when buying a television was what size screen to select. This was usually dictated by your budget and the space you had. Once those variables were determined the project was simple. Buying a TV in the current market is a much more complicated task: there are LCDs, Plasmas, and projectors to choose from. Before a purchase can be made, first one must understand what these options are and how they compare against each other.

LCD stands for liquid crystal diode. LCD televisions send electricity to the diode cells in their screens to spark them into wrapping or unwrapping. Each cell tightens or loosens to a specific point, creating a sift of sorts across the screen that filters the white light from the televisions backlight so that the required color is projected through. Plasma TVs have pixels that are held between two panes of glass. The pixels have gases in them which are released when the pixels are electrically activated. The gases create the exact color within the blue, green and red bands of the pixels.

Until recently Plasma televisions were significantly superior from a number of perspectives. Because of the winding and unwinding motion of the cells in LCD televisions, fast moving video, especially sports and action movies, often displayed a trailing effect as the images changed and shifted. Plasmas do not exhibit this because each of their pixels is activated individually. Plasmas produce undistorted images at sharply-angled viewpoints, unlike LCDs, whose images could appear somewhat corrupted when viewed at similar angles. Plasmas also revealed much deeper colors than LCDs, with especially strong blacks.

Upgrades and improvements in the LCD format have enabled it to match Plasmas in areas that it had shown deficiencies. LCD TVs also have many clear advantages over Plasmas. Plasmas may have at first been able to boast the largest screens, but they by no means have the smallest. LCDs now have screen sizes that can nearly match the largest plasmas, and they can be made so small that they equip many phones. They are also much more portable. Plasmas are very heavy and often thicker televisions, which makes it difficult to transport them. They also cannot be mounted to weaker ceilings or walls because of their weight.

LCDs also do not suffer from many of the drawbacks that Plasmas are plagued by. They do not experience burn-in, or ghosting, which makes them ideal for computer usage where one is typically dealing with mostly still screens. They also can be used at any altitude without distortion because their liquid crystals are not affected by air pressure, unlike the gases inside the Plasma screens.

Plasmas suffer from ghosting, which is the imbedding of a still image on the screen, sometimes indelibly. This makes them less than ideal for computer displays and some videogaming. LCDs do not experience this at all, and they are also the preferred choice of airlines because their picture quality is not affected at high altitudes. Because the gases used in creating the images on Plasma screens are sensitive to air pressure, they need to be relegated to land use. Overall, LCD televisions outperform their Plasma counterparts. At this point they are also competitively priced, making them the clear choice when searching for the right TV.

They are becoming increasingly light and thin, with crisper, clearer images and color saturation with significant depth. They have no half-life, unlike Plasmas. The backlight can burn out, but it is replaceable. They handle glare better than Plasmas because their screens are usually not glass. Theyre also becoming the prominent technology, making the purchase of a Plasma TV risky because replacement parts may become obsolete.

And as far as the household television is concerned, LCDs are much more appropriate and user-friendly than projectors.

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