Sony's 82-inch LCD HDTV prototype is the first xvYCC compliant display
By Barb Dybwad 
posted Jan 5th 2006 8:20AM
posted Jan 5th 2006 8:20AM
We've got some more skinny on the 82-inch Bravia prototype Sony previewed at last night's press event. Featuring full 1920 x 1080 HD resolution, the flat panel prototype is the first display to be compliant with Sony's Extended Video YCC (xvYCC) technology. The point of the xvYCC international video standard is to enable a wider color reproduction capability by expanding the current color data range by about 1.8 times. The displayed range of color on xvYCC-compliant TVs approaches the range of color the human eye itself can recognize. The prototype display also features TRILUMINOS backlight technology which further enhances xvYCC wide color reproduction by using an LED backlight with three independent colors (red, green and blue).
LED backlighting is the wave of the future in all LCD's. It basically solves the one big problem inherent to LCD's - poor black level. The LED's are all individually lit depending on what's going on in the picture, so if there's an area of the picture that's supposed to be black, it really is black - the LED's simply stay turned off.
The extended YCC thing might forever be relegated to high-end sets (it's not really the kind of thing a lot of people would notice in a TV, unless they're major videophiles), but supposedly affordable LED-backlit panels are less than a year away and I predict this technology will be in mainstream sets starting in 2007 or 2008.
I'd like to play Gears of War on this screen.
#1 - If you have fine-grained control of individually colored LEDs, why even incorporate LCD technology? In other words, why not just have an LED display?
Hmm, I'm not an engineer, so feel free to shout me down if I'm talking rubbish, but if the LED's are 'individually lit', what is the point of the LCD at all? Isn't this basically just like a plazma? I'm presuming the answer is that there are a lot less LED's than pixels, but this would make the effect a bit wierd/useless, especially in scenes with lots of mixed bright and dark detail.
I think its because the LEDs are much bigger than LCD pixels. Basically the backlight would affect a whole group of pixels, which generally is what you would want. I havent looked at one of these in person, but i would imagine around the edge of a high contrast change you would see a more normal LCD black instead of true black like the rest of the image.
This individual colour LEDs seems to take it even further - allowing a RED to be more RED by simply not having any blue or green in the backlight, but again, it can only do this over a small area instead of per pixel.
how i wud love one of these in my bedroom. no need to eva come out of it!!
LED backlighting has NOTHING to do with black level. Blacks are still provided by the LCD holding back the LED's light, not by dimming the LEDs.
The gain from the LEDs come from the much wider color gamut they allow. The gamut of regular backlights (basically fluorescent tubes) is really poor. It's a huge compromise -- an attempt to create a muddy white from a bunch of emissions that aren't really pure primary colors, but are instead the best that can be gotten from running a current through rare earth compounds within a single tube. On top of that there are big gaps in the spectrum as the gas doesn't fluoresce in a linear way (unlike much more linear incandescent light.) It's just not attractive and many colors are badly attenuated or shifted because of the gaps. It's why people look better under incandescent light than fluorescents.
LED backlighting is much better as it's not one source of pseudo-white light, but three discrete LEDs combining to generate white, so each LED can be engineered with a more linearity and a much closer match to a pure primary (making it possible to render more intense colors.) They're also intensely bright, which isn't as important on a computer monitor but would matter if you're watching TV in a bright room.
LED backlighting will be the only defense to the new SED technology going forward, imho. From what I've seen, SED still takes the cake. LED backlit lcd's require a fan due to the heat.
If you want to read more about LED backlighting, Nikkei Electronics Asia ran a good technical article on the topic back in March, 2005.
Read "LED Backlights Boost LCD TV Color"
http://neasia.nikkeibp.com/neasiaarchivedetail/000503
If you want to read more about LED backlighting, Nikkei Electronics Asia ran a good technical article on the topic back in March, 2005.
Read "LED Backlights Boost LCD TV Color"
http://neasia.nikkeibp.com/neasiaarchivedetail/000503