Quattron

Diagram of Quattron's 4-pixel structure.

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,^[1][2] and which may mimic more closely the way the brain processes color information.^[3][4] The screen is a form of multi-primary color display, other forms of which have been developed in parallel to Sharp's version.^[5][6]

The technology is used in Sharp's Aquos LCD TV product line, particularly in models with screens 40 inches across and larger.^[7] 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".^[8] Another commercial had Takei advertising the 3-D model with the Minions from the 2010 movie "Despicable Me".^[9]

Criticism

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.^[10]

Scientific analysis

Spectral response of a common Quattron display. The white response was compared with each of the four primaries, given by the respective colored lines. It may be observed that yellow light produced by the display is simply the sum of the light that passes through the red pixel and the green pixel.

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.^[11]

See also

• Color depth
• Gamut
• Opponent process, a color theory which considers yellow a primary color in addition to the classic RGB color model.^[3]
• PenTile (RGB reproduction via RGBG, RBGW etc.)
• Tetrachromacy, a different biological system from trichromacy, possibly found in some people
• Trichromacy, scientific description of the RGB model for human vision

References

1. "Sharp Promises Quattron TV Will Wow" CNET Asia, March 23, 2010
2. "Sharp Quattron LC-46LE820M" review by Ty Pendlebury, 16 July 2010, CNET Australia
3. Jay Garrett (2010-03-10). "Sharp Aquos Quattron TV Brings in Yellow Fourth Pixel – RGBY". GadgetyNews.com. Retrieved 2010-04-13.
4. Wakabayashi, Daisuke (26 January 2010). "Sharp Expands Its TV Color Palette". The Wall Street Journal.
5. parallel LCD design from Genoa Color Technologies website Archived January 8, 2012, at the Wayback Machine.
6. multi-primary color display research from GCT Archived April 25, 2012, at the Wayback Machine.
7. Aquos product information at Sharp website
8. Sharp Press Release: Sharp National Brand Advertising Campaign Adds Color to Dynamic HDTV Landscape – "You Have To See It, To See It"
9. platteTV (2010). "Sharp AQUOS Quattron™ 3D TV - George Takei and The Minions". Sharp Corporation. Retrieved 27 January 2012.
10. Dr. Raymond Soneira (July 2010). "Maybe Sharp Should've Consulted Mr. Spock Instead" (PDF). Maximum PC magazine. p. 51. Retrieved 19 August 2010.
11. Thomas Bangert (19 February 2014). "Appendix C: An Analysis of Quattron" (PDF). Queen Mary University of London. p. 87. Retrieved 19 February 2014.

External links

• Aquos LCD TV (Sharp website)
• Sharp LC46LE821E Review – Technical assessment of Quattron TV by David Mackenzie at HDTVtest