If you’re buying a new flat screen television I’m sure you’ve come across a class of TV that manufacturers have labeled as “LED TVs”. This can be somewhat misleading because people may think that because of their relatively higher prices compared to the older LCD flat screens, they are a different technology altogether. But the truth is that they only differ in the lighting technology that they use.
The liquid crystal displays (a.k.a LCDs) used in most of today’s screen displays can only show images when they are lit. Usually the lighting is done behind the LCD (backlighting) and the conventional lighting material used for such were fluorescent lights (particularly cold cathode fluorescent lights or CCFL). So therein lies the difference— whereas LCD TVs use CCFL for backlighting, LED TVs use light-emitting diode (LED) technology. It’s all in the lighting!
Edge lighting vs. Full LED array/matrix
But why then would you go for an LED-lit LCD TV? One great advantage of these devices is that since you can get LEDs in much smaller sizes than flourescents, LED TVs make for lighter and thinner screens. Many designs these days actually use LEDs for edge lighting configurations instead of the usual backlighting configuration were LEDs are lined up in arrays forming a matrix of LEDs behind the LCD panel. Edge lighting has the very distinct advantage of making TVs thinner and lighter because you don’t have to put too much stuff behind the LCD panel. However, full array designs are usually better in picture quality because they usually have provisions that make “local dimming” possible. This refers to the ability to control small or local areas of LEDs behind the LCD such that some can become brighter than others and vice versa. The benefit of this is the ability to produce better contrast. Blacks can be blacker or whites become brighter because you can simply turn the LEDs behind it dimmer or brighter. In fact, if you want black you can just locally turn the backlighting off while other areas of the screen are lit independently depending on the picture being shown. This ability of full array LED TVs is the reason why they are being touted to have closed the gap against the picture quality of the plasma TV.
Other advantages and disadvantages of LED TVs
And yes it doesn’t end there. Another good thing about these LED devices is the fact that they are more energy efficient. They are probably the best in these terms especially compared to plasma TVs and the conventional CCFL LCD TVs. Also in terms of initial cash outlay (when you go buy one) gone are the days when you had to spend a fortune if you wish to get a good LED LCD TV. Most manufacturers already offer discounted models. Of course some models are still priced pretty high but these are usually the really big screen units units that come with the “Smart” designation which really just mean Internet-ready flat screen displays which you can use to get Internet content aside from the usual TV content. Some designs have even incorporated the use of fancy operating systems (like the Android OS) to make it compatible with modern mobile devices like smart phones, tablets and computers.