Chris Hall, DigiTimes.com
Start-up Genoa Color Technologies has developed technology that significantly enhances the picture produced by a wide variety of display types, including TFT LCD, front- and rear-projection systems, and color-sequential systems. Genoa calls its technology multi-primary-color (MPC), and it works by adding further primary colors to standard RGB for an expanded color gamut and increased brightness. Genoa's current business includes the sale of the Keshet family of ASICs, which implements Genoa's own software algorithms to enable this type of enhanced display.
DigiTimes.com spoke recently with Genoa EVP Hafiz Haq, who manages business development at the company's Asia Pacific Office in Hong Kong.
Q: Can you describe Genoa's technology in a simple way?
A: There are two very important aspects of Genoa technology. One is the idea of the actual display. We have intellectual property on multiple-primary displays, and based on numerous projects with customers, we have expertise in their design and the electronics required to run them. Genoa has already, at a very early stage for a start-up, written a number of patents and continues to write patents for multi-primary display systems and algorithms.
The second aspect of our technology is color conversion and color processing technology. We have developed the know-how and the IP involved in converting standard inputs to four, five or six primary colors, supporting the extended gamut display capabilities of the multi-primary devices, and the conversion of standard signals (RGB or YCC) to a larger gamut display space. We know how to do all that and achieve very attractive pictures. Genoa's conversion and color processing algorithms draw upon the company's very deep knowledge of color. That expertise originates with the company's founders, who had a background in the printing industry.
Q: How did Genoa come into existence? What is the general background to the development of your display enhancement technology?
A: That is an interesting story. In printing, almost all processes are now automated and achieved electronically, with the exception of proofing and proof reading. This means that at some point a sample is created, which then has to be physically delivered to the customer, via Fedex, let's say, and a variety of logistic mechanisms. Fedex delivers, obtains the customer's signature, and the customer's response to the sample then has to make a return journey through the same logistic chain. Not surprisingly, the printing industry was looking at methods of doing all this electronically, but that requires a display technology with both a wide color gamut – at least that of ink on paper – and extremely accurate color reproduction. Current display technology has a very poor ability to reproduce accurate colors, and Genoa's first mission, therefore, was to produce such a display, which we did successfully.
Nevertheless, Genoa's board of directors decided to change direction. The board's thinking was, “Well, if we can do that, why simply target niche applications for the printing market? Why don't we instead target the consumer market, where there is a need for improvement in the color gamut?”
That is the background to Genoa, and we've managed to develop the application of this color know-how to electronic displays by hiring industry experts in Optics, Electronics and Displays.
Q: In that initial stage of development for the printing industry, Genoa's founders learned a lot?
A: Yes. And I would like to add that the beauty of Genoa's technology is that in a normal RGB display, when you try to increase the color gamut you are penalized by a reduction in brightness. That was one problem. The other problem is that the RGB color space, which forms a triangle, is like a short blanket that leaves the shoulders bare. It cannot cover both the yellow and cyan sides of the color gamut; and it cannot match the “real world” gamut of film. Genoa's ambition was to come as close as possible to a cinematic color gamut, one that covers the yellow and cyan spaces in addition to extended RGB. The benefit of using the multiple-primary method is that we can achieve an enlarged gamut, with the additions in the right color areas that matter for improved image perception and without being penalized by a loss in brightness. We can maintain the brightness, and in some cases we can even increase the brightness.
This represents almost a paradigm shift for the displays industry. When you tell people in the displays industry that you can increase the gamut without a loss in brightness, and quite possibly have an increase in brightness, they are surprised. The simplest explanation is that we make use of more bright colors, such as yellow and cyan, and make better use of the spectrum of the lamp – both the CCFL backlight in LCD and the UHP lamp in projection. There is simply more light passing through the Genoa's device system.
As an illustration, when you make a five-color display, you can use a five sub-pixel arrangement, which means five transistors, as compared to three (RGB), are incorporated in each pixel. That means there is an overall lower aperture ratio per pixel, but despite that, we do not lose brightness. The explanation is that in a multiple-primary display, the red light in the backlight passes not only through a red-color filter but also through a yellow-color filter, and similarly blue light passes not only through a blue-color filter but also through a cyan-color filter. Therefore, we simply make better use of the spectrum and achieve greater light efficiency. The result is higher brightness and a wider, more natural, cinema-like color gamut.
Q: Was this effect discovered accidentally or was it designed?
A: It originated with our understanding of color in the printing business and was designed into our electronic displays. Just as, in printing, color is enhanced by using additional inks, so we understood that we could enhance color by adding primaries. The breakthrough came when we selected those additional colors in the light of the spectrum of the illumination, and, targeting cinematic color – that is to say, a cinema gamut – we deliberately demonstrated what we had set out to achieve: enhanced color without any loss in brightness.
For example, we have demonstrated how, by making a five-primary-color LCD panel, we can increase the gamut from approximately 72% to 95% of the NTSC gamut, while delivering the same brightness with the same backlighting system.
And I would like to add one comment. When you look at the shape of our 95% gamut and compare it to the cinema gamut, you find that the 95%-gamut shape is very similar to, or comes very close to, the cinema gamut. By contrast, if you had a triangular gamut based only on RGB, but also at 95%, and you then compared the picture performance, you would find that the multiple-primary 95% gamut would result in a much better picture because it would cover the yellow and cyan much better than would RGB alone.
Q: Yellow and cyan are obviously very important primaries for natural color?
A: Yes. If you look at colors in nature – flowers and gold, for example – there are numerous very bright yellow colors, while cyan is used to represent sky and sea – colors that are obviously very important colors in nature.
Q: And with a traditional RGB TV, you are losing a lot of that natural coloration?
A: Yes. The industry saw that clearly at CES where our “Scene-to-Screen” demonstration captured a display of both natural and synthetic objects with a live camera and showed them on both standard RGB and multi-primary screens. The MPC display showed both the out-of-gamut and the in-gamut colors accurately, while the RGB display caused significant distortions of in-gamut colors, as well as, of course, distortions of the out-of-gamut colors. We showed, for example, that a cyan glove was accurately reproduced on an MPC display but looked almost blue on an RGB TV.
This is Part I of a four-part interview. Read more at DigiTimes Part II, Part III, Part IV.
|Hafiz Haq, EVP Genoa Color Technologies
|This chromaticity diagram compares the color gamut of standard TV and Genoa’s multiple-primary technology. The outer elliptical line show the complete CIE gamut for human perception of color (the numbers indicate wavelength). The black-line triangle indicates a standard TV gamut (REC 709 or EBU). The colored pentagon shows the gamut of a 5-primary LCD panel implementing Genoa’s technology. This gamut is greater than 95% NTSC, based on available color filters.|