LED TV Explained
There seems to be a confusion of the term LED TV which had been strongly advertised in the media. Is this a new television technology? Actually it is not. An LED TV is actually the same LCD TV we had known all this years, what is different now is the backlit system ( more explained latter). The LED TV is actually and LCD TV making use of LED (Light Emitting Diode) as the back lit light source.
Now here is the explanation about backlit.
LCD TVs are all backlit due to the fact that LCDs are a transparent type of display technology. This means the technology do not generate their own light like in plasma.
Thus in order for LCD TV to form an image on the flat panel display, its pixels have to be backlit by a separate light source. Some thing like the olden days film projectors. The separate light source that most LCD TVs used is the cold cathode fluorescent lamps (CCFL).
The lights deliver good colors and brightness, and decent contrast, but not great blacks. But TVs utilizing brighter LED backlighting can achieve much better blacks, as well as brighter colors and even greater contrast ratios. Contrast is measured between the darkest lit areas of the screen to the brightest area.
But just in case you thought your selection choice was now made easy, there are a couple of LED options – full matrix LED and edge lit LED TVs. Let’s go through the differences and look at what some of the manufacturers are using as their preferred backlighting choice.
Clarification: Is there really an LED TV?
Actually there is but you will need a very large room like a stadium. A true LED TV is one of those giant screens you usually see at outdoor stadiums, at grand prix events and rock venues. They are large screens made up of thousands of extremely bright LED lights. However the sizes of LEDs are too big to be use in your normal TVs, but they are ideally suited as a light source for backlighting LCD crystals.
How LED technology is used in LCD TVs
Edge lighting
Edge lighting is pretty much as described. In this method, a series of LED backlights are positioned along the outside edges of the screen. From there, the light is dispersed across the screen, which means the LED/LCD TV can be made very thin. And while the results may be better than CCFL screens, the black levels in edge lighting are not as deep and, if you look closely, the edge area of the screen tends to be brighter than the middle viewing area.
Full-array backlighting
To take full advantage of LED lighting, some manufacturers use full-array LED backlighting, where many rows of LEDs are placed behind the entire surface of the screen. Although this makes for a thicker TV panel, the LEDs provide more even, brighter colors and greater contrast.
Manufacturers who are introducing this technology to their TVs include: Samsung, Toshiba, LG and Metz.
Expect to see more improvement to this LED backlit technology. At the moment, most LED backlighting is provided by white LEDs that cost less than the red, green, blue ones. But as popularity and demand increase, and research continues to improve, expect to see RGB LEDs, that provide a much greater color gamut and therefore much richer, denser and varied colors, being incorporated into TVs. Apparently a number of manufacturers including Sony and Sharp have models with RGB LEDs.
Features of LED backlit LCD TVs
* An LED TV achieves deeper blacks as well as emitting brighter images, thereby producing better contrast ratios;
* They are slimmer (especially edge-LED lighting systems);
* They deliver better viewing angles than other LCD TVs;
* LEDs are long-lasting;
* LEDs are more energy efficient than their CCFL counterparts, and better than plasma Tvs and much better than CRTs;
* LEDs don’t use mercury like some other backlighting methods.
Popularity: 7%
