HDTV Almanac - CES 2010: Four-Color LCD HDTVs

[alfredpoor]

I know that at least some of you frequent HDTV Almanac readers are old enough to remember when the NBC peacock revealed a major change in television technology. Overnight, we went from shades of gray on the TV screen to full color (or what was close enough to full color for us at the time). [...]

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[jordanm]

I saw this at CES. The photograph does not do this technology justice, although it tries. It looked very good.

[papasmurf]

I would love to know how this system works. Sharp has always been a leader in LCD quality pictures. Three years ago I purchased a Sharp LC-46D92U. It has what they called a '5 wavelength backlight system' to produce a greatly enhanced color pallett. As readers know a weakness of LCD TVs has been the CCFLs used as a light source. They do not produce full bandwidth light as does a 'black body radiator' such as a quartz lamp. In the 46D92U Sharp used 5 different colored CCFLs to produce truly 'white' light. The result is a picture second to none, even today. Now LED backlights are also difficient in some portion of their visible light output spectrum. What does the new color system using yellow do to address that?

[alfredpoor]

[img]http://hdtvprofessor.com/HDTVAlmanac/Sharp_RGBY_pixels.jpg[/img]

Here's a picture of the pixel structure. The left is the standard RGB structure. The right shows how a yellow sub-pixel is added between the blue and red ones.

This extra section of color filter does expand the color gamut, but it also depends of the LED backlights to provide the expanded light spectrum to make it possible.

Alfred

[Richard]

DLP has been doing this for quite some time...

[alfredpoor]

Yes, both DLP and LCoS microdisplays have used multicolor wheels to increase the color gamut. They also have wheels with "white" sectors that increase brightness. The difference is that the pixel size on the microdisplay doesn't change; the speed with which the light color changes may increase, so you get all the colors in the same frame rate as the traditional RGB.

Sharp's approach squeezes more sub-pixels into each pixel, making each one smaller. This adds processing steps to the manufacturing, and probably decreases the aperture ratio, so the amount of light that gets through is decrease.

The extra colors don't really add much cost to the microdisplay sets, but I expect they add significant cost to the LCD panel. In a business that doesn't have room for extra cost, I'm not sure that this will be a winning strategy.

Alfred

[kurt]

I'm a novice to the HDTV world and am intrigued by the RGBY idea. As an exercise in novelty, I was wondering how much Sharp wants for their LC-82MX1U. They don't seem to have it on the SharpUSA website. I'm wondering what happened to it! Is it only available overseas? Thanks!

[alfredpoor]

Sharp does not list prices for any of their RGBY models on their Web site, and I cannot find any press releases that indicate ship dates. They were announced last January at CES, so I'd expect them to be on the market in time for the holidays, but I've learned not to believe anything until you can actually buy something.

Alfred

[kurt]

Thanks, Alfred. I'll keep my eyes peeled and ears to the ground!

[videograbber]

Thanks for the comparison picture. I found it quite interesting.

I.e., the pinks look much better on the Sharp screen too. And so do the greens, what bits of them there are. Much more dynamic. Hey, ALL the colors look richer and more saturated, less washed out. It's AMAZING how simply adding yellow to the palette did all that! Wow!

What a load of bollocks. I could adjust the set on the left to look identical to the "new, improved" set on the right. And so could almost anyone else. They've screwed with the contrast, saturation and gamma on the left set to make it look deficient, and boosted the settings to exaggerate it on the right set. A set is either accurate, or it's not. And turning everything into a Technicolor cartoon isn't going to make anything more accurate.

Anyone in the market for snake oil? I've got some to sell that's guaranteed to cure all your ailments.