What kind of backlighting do LCD HDTVs use?

Answer 1

The first main type of LCD illumination is called CCFL. CCFL uses strong bulbs - mainly florescent to light up the screen. Newer HDTVs have now switched to using LED technology, as LED lamps are smaller, less expensive to produce, maintain, & deliver better results than the CCFL illumination. There are three types of LED LCD back-lighting configuration for all modern HDTVs. The first type is called edge-lighting LED. Edge lighting uses LED bulbs built around the back edges of the screen. This configuration produces results worse than full LED illumination, and sometimes even worse than CCFL. It's used to make TVs very thin, mainly the ones that you can hang up on the wall. The second type is the fully lit LED LCD. This configuration (also known as Full Native LED LCD lighting) has the same round LED bulbs used in edge-lighting, except the entire back of the screen is populated, instead of just edges. This produces a much better picture than the edge lit displays, while the TV will not be as thin, and at a bit higher energy cost. The third type of LCD HDTV back-lighting configuration is the fully lit LED LCD with local dimming. This configuration supports the same fully populated LED illumination, except special TV software controls which bulbs are left on and off, all based entirely on the picture. Let's say there is a picture of a night in Paris with a lit up Eiffel Tower, local dimming option keeps the bulbs behind the black sky off, thus providing a darker black sky. The LED bulbs behind the light tower however will be lit up. Local dimming (also known as the dynamic dimming) is considered to be the best type of back-lighting because it constantly changes the lighting to serve each individual image displayed.