LED Backlighting vs. Edgelighting

I was asked about the differences between Backlighting and Edgelighting on HDTVs...

I'll start by saying I prefer plasma if you have some control over the lighting in the room and don't have a window or lamp directly behind your viewing position. And I do prefer LED-illuminated LCD TVs over CCFL-illuminated models.

As for LED edgelighting versus backlighting, I strongly prefer backlighting, because edgelighting usually results in poor screen consistency, especially in dark scenes. Such images usually have lighter and darker areas because it's nearly impossible to distribute the light from LEDs at the edges evenly across the entire screen. By contrast, LED backlighting often results in much more consistent illumination in dark scenes.

Also, LED backlighting typically provides a feature called local dimming, in which the LEDs behind dark portions of the image are dimmed to make then darker, which yields much greater contrast and better perceived blacks. However, this doesn't mean LED is the answer to all display problems.  LEDs are dimmed and brightened in relatively large clusters or zones, so things like stars or white text on a black background can look like they have halos around them. As you can see in the illustration above, the "backlight simulation" shows what the image would look like if you were looking only at the LEDs, which form a black-and-white image with much lower resolution than the final image on the LCD panel itself.

Plasmas don't have any of the problems that LCDs try to overcome with various technologies, and they have no off-axis picture degradation that all LCDs suffer from to one degree or another. This is why I prefer plasma over any type of LCD as long as you can deal with plasma's shiny screen. I have one in my living room with a massive window and really it doesn't create any issues.  You just have to ensure before using Plasma, that you don't have any reflective issues in the space you're using.

If you need more comparisons between the different technologies?
Start hereLED vs OLED or LCD vs Plasma or take a look through "What you need to Know" in the menu.

Worst case scenario, just forget TV and go to the gym and work it out!