RGB vs RGBY: Does Adding Yellow Really Improve TV Image Quality?

By Bobby Schweizer

Sharp will soon be offering its four subpixel Quattron 3DTV. Is the world ready for RGBY?

At CES in January Sharp announced their QuadPixel technology which, as you might expect, adds a yellow fourth pixel to the current red, green, blue array of subpixels that make up your LCD television's display. The benefit? Adding the additional subpixel supposedly increases the number of colors that can be displayed from the billions to the trillions. If you're into watching TV with trillions of colors, Quattron four pixel technology can be found in Sharp's new line of Aquos TVs. And if you're into 3D, Sharp is bringing their Quattron 3D TVs stateside.  

Quattron 3DTV claims to be the brightest 3D television and that the addition of the yellow pixel compensates for the dimming of the 3D glasses. The gradient created by the addition of yellow is also supposed to reduce ghosting effect that comes from neighboring pixels influencing each other's display in the left-eye/right-eye images. But is this little yellow pixel really the future of LCD displays?  
CNET commented, however, that TVs "are plenty bright already" but that the yellow pixel could make it more energy efficient to display brighter images. CrunchGear joked that the fourth pixel can "improve, well, videos of sunflowers and Big Bird." Sharp claims that the new subpixel allows for not only more accurate yellows and golds, but "Caribbean blues" as well. It all sounds well and good, but can we really take advantage of this technology?   
Video expert Bram Desmet notes that while capable of displaying nearly 1.1 billion colors, the additional colors are not native to the 8-bit broadcast and must be invented through interpolation by image enhancement software. He also raises the question of human perception: while we can see more than the billion colors available in RGB-subpixels, how many colors do we really need before we "completely eliminate perceivable banding"? In this, in-depth analysis of Quattron, CNET wrote that the yellow pixel has negative effects on the viewer preferred 709 color gamut standard to HDTVs.  
The additional yellow pixel is not a bad thing, but the overall consensus is that it's an unnecessary feature for current home theater content. If brightness is what you're after, perhaps Nano Lighting or OLED with its blacker-blacks are better alternatives. The fourth subpixel may have its day, but for now is too gimmicky to justify the premium price. 
Do you have a 3D TV? Ever spent time with one? We'd like to know what you think of the picture quality in comparison to a normal HDTV.