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LED Television (Light Emitting Diode Television) is also a LCD (Liquid Crystal Display) television which differs these both by the back lighting technology. The LED tv uses LED backlighting rather than fluorescent lights used in conventional LCD televisions.

This is simply called LED TV as a marketing move to emphasize consumers it's backlighting technology. But it is confusing consumers.

Conventional LCDs used fluorescent tubes to light the screen. As a result, LCDs have problems creating deep black areas on the screen. The fluorescent tubes are always on across the screen horizontally and some light comes out even those areas supposed to be dark. So the picture sharpness comes down with lack of dark areas. Also, fluorescent tubes are limited in color range and therefor the image saturation is bit low.

LED TVs uses LEDs to illuminate the display. There are two ways to use LEDs as the light source in LCDs. The first way is to place LEDs across the entire back of the display (backlit) while the second way is placing the LEDs around the inside frame of the TV which is called "Edge Lit" display. Both these use less power consumption comparing to conventional plasma TVs and LCD TVs, backlighting with fluorescent tubes.

So which LED technique is better?
There are advantages and disadvantages in both these. But when it comes to the pictures quality and more contrast, the backlit technology which the LEDs are positioned back of the screen is better.

Edge - Lit LED TVs

As the name impress, LEDs are positioned around inside frame of the TV. As a result, the thickness of the item has become very small. It is as thin as about 9.9mm. The light emits by the LEDs placed around the TV is spread across the back of the screen and therefor it is bit hard to show deep blacks in various positions on the screen. That is the reason why that Edge-lit LED TVs cannot produce high contrast pictures as Backlit LED TVs.

An advantage of Edge-lit LED TV is less power consumption than standard LCD TVs and also than Backlit LED TVs.

Backlit LED TVs

In Backlit LED TVs, LEDs are positioned back of the screen and they are grouped into blocks. Each and every block can be switched off separately and when a block of LEDs are switched off they produces true black which is not possible with fluorescent tubes. This will help to show pictures with more contrast. This technique is called "Local Dimming". So some LEDs can be switched off while some are switched on in different parts of the screen. A disadvantage of using blocks of LEDs to produce light is, in an image with a mixture of bright and dark areas, some dark area can be effected by the switched on LEDs which use to show bright area. To overcome this issue it is better to use one LED for each pixel and each LED can be switched off. But is it very expensive solution.

Currently, backlit LED TV produces much better picture quality rather than traditional LCD TVs and even Edge-lit LED TVs. Also backlit LED TV uses RGB LED lights to improve the color spectrum and that too helps to produce better quality pictures.

Power consumption is high in these backlit TVs, even more than standard LCD TVs. Specially the ones that use RGB LED. These TVs cannot be as thin as edge-lit LED TVs because the LEDs are positioned back of the screen.