Television (TV) is a telecommunication medium for transmitting and receiving moving image that can be shades of grey or multicolour. Images are usually accompanied by sound.
EARLY KIND OF TELEVISION
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CATHODE RAY TUBE
The development of electronic television systems was based on the development of the cathode ray tube (CRT). A cathode ray tube aka picture tube, was found in all electronic television sets up until the invention of the less bulky LCD screens
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THE ADVANTAGE OF CRT
$.Less expensive
$.Highly contrast-because CRT TVs make use of light beams and phosphors, which are good color projectors.
THE DISADVANTAGE OF CRT
$Heavy-because of the old technology used in manufacturing the displays, CRT TVs are comparatively heavier than the modern display systems.
$Need large of space-bulkier, so the bigger the screen gets, the more space is required
GET FROM: http://www.associatedcontent.com/article/180134/advantages_and_disadvantages_a_crt_pg2.html?cat=15THE INNOVATION OF TELEVISION IS DONE NOW A DAYS
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LCD TELEVISION
Television set that use liquid-crystal display technology to produce images.
THE ADVANTAGE OF
Screen Size
LCD sizes start in the widest range. Typically 13 to 65 are the most common but some manufacturing offer LCD displays in up to 100 sizes.
Contrast/Brightness
LCD TVs are most versatile, and look better, in the typical viewing situations because they do not reflect light like some TV screens do.
Screen Thickness
LCD screens can be as little as 2 deep. This gives more options for placement including wall and ceiling mounting.
Life Span
Life span for TVs are measured in half life hours (50% of original brightness). Most LCD TVs have a half life of over 30,000 hours (16 years of viewing at 6 hours per day).
High Altitude
High altitudes do not affect LCD TVs .
Shipping
LCD TVs are fairly simple to ship. They are lighter than standard TVs .
Pricing
LCD TVs are very economical to operate because they require little if no maintenance and when buying screens less than 35 are fairly reasonable in cost.
DISADVANTAGE OF LCD
Viewing quality
LCDs were initially designed as computer monitors. As a result very few are made for video viewing. Do not buy a display with a tuner upgrade if you are planning to use it as a TV buy it with a built in tuner. If you are using it as a TV and a computer monitor (dual purpose) buy one with a computer input rather than a display with a TV tuner. There IS a big difference.
Screen Size
Be careful about no name units when buying a display over 30. Some pictures are virtually un-viewable in fast action video.
Contrast/Brightness
Most LCD units have a difficulty going fully black because they are displaying through the LCD panel. Blacks have a tendency to be very dark grey rather than black...
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PLASMA TELEVISION
A plasma display panel (PDP) is a type of flat panel displayfcommon to large TV displays (80 cm/30 in or larger). They are called "plasma" displays because the pixels rely on plasma cells.
ADVANTAGE OF PLASMA TELEVISION
Exceptional Color: Plasma TVs display up to 16.77 million colors - more than the human eye can even register - to provide a highly accurate, lifelike picture.
High Resolution: Plasma TVs are able to display a high resolution, and are capable of displaying HDTV signals.
Slim, Lightweight Design: A key advantage of the Plasma TV is it's thin, flat-panel design, often only inches thick.
Price: Although still more expensive compared to direct view or rear projection TVs, Plasma TV prices have fallen dramatically, and are now quite affordable.
Uniform Screen Brightness: Compared to rear projection TV's, Plasma TVs offer perfectly uniform screen brightness.
Magnetic Field Immunity: Since Plasma TVs use different technology compared to conventional TVs, they do not suffer distortion when placed in proximity to a magnetic field. Speakers can be placed next to, below, or right on top of Plasma TVs with no adverse effects.
DISADVANTAGE OF PLASMA TELEVISION
Potential Burn-In: Because of the phosphor technology in Plasma TVs (see How Plasma TVs Work), it is possible for traces of an image to be 'burned-in' to the display. This is generally only a concern in commercial uses, where images are displayed for long-periods of time.
Lower Brightness: Although still considerably brighter than rear-projection TVs, direct view and LCD TVs often are able to provide a brighter picture. This is generally only readily noticeable if watching in a very brightly lit room.
-Shorter Life: Compared to other television technologies, Plasma TVs do generally have a shorter life span, and there is no option to repair a burnt out tube or backlight. Most Plasma TVs have a life span of 20,000-30,000 hours based on manufacturer's estimates.
-Fragility: Plasma TVs are a very fragile technology, and the units are quite easy to damage. Extreme care must be used when moving them, as even laying the Plasma display on it's side can have adverse effects, possibly damaging the unit irreparably.
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