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I read an article saying that the luminance of LED increases/decreases linearly as flow of electricity.

If so, can I assume that an LED panel is better in quality of Grayscale Reproduction or Gamma compare to a CCFL panel?

I also guess that there must be differences between full-array/edge-lit and RGB/White LED... Is it right?

Any comment will be appreciated, thanks.
 

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There are no "LED panels" - all panel displays currently being sold are plasma or LCD. Some LCD panels have LED light sources, but the LEDs do not create the images... the LCD panel creates the image, the LEDs only create the light that makes the images visible.


Edge-lit LED backlights are TERRIBLE for anybody interested in high quality images. Edge-lighting requires very special diffusers, but they are still very far from perfect at the job they do. When the panel shows a black "image" there are bright spots and dark areas that are so obvious, they can be seen during every reasonably dark scene. Edge-lit LED backlights also are not capable of local dimming - which, done well, really does make better-looking LCD images even though it's not a perfect solution, I'd rather have it than not have it if I was using an LCD display (plasma panels still have better image quality on average though). Thin, edge-lit LED backlight LCD panels are lifestyle products... not products for people interested in high quality video images.


You can't assume ANYTHING about ANYTHING when it comes to video displays. It doesn't matter AT ALL if something being used for a backlight responds to changes in voltage with linear changes in light output. If a lighting device was non-linear in its voltage response, you would simply provide an inverse curve to produce a linear end result.


RGB and white full-array (behind the LCD panel) LED backlights can produce similar high quality images. The top of the line 2009 Sony panel used RGB LEDs but the 2010 model uses white LEDs. I can't see any obvious image quality difference between the two but there might be something if you could place the 2009 and 2010 models side by side sharing the same feed. It's not going to be anything obvious though. Local dimming works better on the 2010 model, perhaps because there were so many white LEDs... amost 900 of them in a 52" panel. With that many LEDs, you have more control about which ones are on and which ones are off. That makes the "halo" around objects surrounded by black much smaller on the panel with the most LEDs in the backlight (presuming they can be controlled individually - many (all?) local dimming LCD panels use groups of LEDs for dimming or brightening the image area - controlling LED brightness by groups of 4 or 8 or 9 LEDs in a large white LED array means you won't be able to control the light level of each LED independently... maybe you can change the light level for 4 or 8 or 9 LEDs at the same time. That's an unfortunate technology limitation that may get resolved in the future so that each individual LED can be controlled independently.
 
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