LED (light emitting diodes) is the newest LCD (liquid crystal display) technology, which has hit the markets in 2009. The basic difference is that the newer LED flatscreens have backlighting behind the LCD panel. This backlighting is either edge-lit with lights around the edge, or has a sheet of LED lights behind the entire LCD panel. Normally the edge-lit LED HDTVs are slimmer than backlit models. The trade off is that typically edge-lit models do not have true local dimming. Local dimming is capable of producing extreme bright images next to extreme dark images. The color of the LEDs is also a factor; red, green, and blue LED lights create deeper more realistic colors than white LED backlighting.
Traditional LCDs use fluorescent lights and have a contrast ration of less than 100,000:1. The newer LEDS have a contrast ratio of 2,000,000+:1 and produce a far superior picture. When looking at a LED vs. LCD the difference is not even comparable. LEDs are the winner, hands down. They are however extremely bright, which isn’t a bad thing. It’s just that Plasmas have darker black levels. A better question is: What is better Plasmas or LEDs?
