Quattron

Quattron is the brand name of an LCD color display technology produced by Sharp Electronics. In addition to the standard RGB (Red, Green and Blue) color subpixels, the technology utilizes a yellow fourth color subpixel (RGBY) which Sharp claims increases the range of displayable colors, and which may mimic more closely the way the brain processes color information. The screen is a form of multi-primary color display, other forms of which have been developed in parallel to Sharp's version.

The technology is used in Sharp's Aquos LCD TV product line, particularly in models with screens 40 inches across and larger. The technology, distinct from the product line, has been advertised featuring George Takei as the spokesperson in the debut commercial, in which he uses his catchphrase "Oh My". Another commercial had Takei advertising the 3-D model with the Minions from the 2010 movie "Despicable Me".

According to an analysis by Raymond Soneira, president of DisplayMate Technologies, a video calibration equipment producer, the industry-standard color spaces used by content providers mean there is no existing source material that contains the fourth color channel. He therefore concludes that any "extra" colors displayed must be created in the television itself through video processing, resulting in exaggerated, less accurate color.

Color researchers at Queen Mary University of London investigated the Quattron technology and found that although Quattron does have four physical color sub-pixels it does not have a fourth primary in the backlight to drive it (yellow is approximately 575 nm). In other words, Quattron has a yellow sub-pixel to let light through, but the manufacturer has not made any provision to produce the yellow light needed to pass through it. (The yellow subpixel merely lets through more red and green light.) On that basis they conclude that it serves no useful function.

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