Screenshot of Adobe’s Kuler app showing color extraction from a photo
Adobe recently released a new iPhone app called Kuler that let’s you extract colors from your surroundings using the phone’s camera. It’s a useful tool that allows designers to capture color inspiration wherever they find it and easily incorporate it into their work via color palettes.
The app also highlights a weakness in current display technology: no display on the market today can actually reproduce all the colors we see in the environment around us. So, even if the camera sensor can capture that color you love, you may not be seeing an accurate representation of it on your device.
The iPhone 5’s LCD display is designed to cover the sRGB/rec.709 color gamut standard used for HDTV broadcasts. And, it looks great but compared to the world we see around us, it’s just not quite as rich. If we plot the iPhone 5’s color gamut against the gamut of colors found in nature, the phone comes up short in important reds, greens and cyans:
Color gamut of the iPhone 5’s display compared to the gamut of colors found in nature. The iPhone 5 comes up short in red, green and cyan.
If DisplayWeek 2013 was any indication, color has once again become a hot topic in the display industry. Color gamuts are getting larger and it may not be long before we see a display that can match what our eye sees in nature. Over the course of the next year, we will start to see more wide color gamut-capable devices as OLED continues to expand marketshare and new technologies like quantum dot LCD begin to enter the market in volume.
Apple CEO Tim Cook spoke at Goldman Sachs’ Technology and Internet Conference yesterday. He touched on a wide range of topics from what Apple plans to do with its cash horde to the state of its retail operation. When it came to a question about making lower cost products, Tim used display quality to help make a point about creating great user experiences:
The truth is, customers want a great experience and they want quality and they want that a-ha moment each time that they use the product, and that’s rarely a function of any of those things.
If you look at displays, some people are focused on size. There’s a few other things about the display that are important. Some people use displays, like OLED displays, the color saturation is awful. And so if you ever buy anything online and you want to really know what the color is as many people do, you should really think twice before you depend on the color of the OLED display. The Retina display is twice as bright as an OLED display. I only bring these points up to say there are many attributes to the display, and what Apple does is sweat every detail.
He makes some fair points here. If a display is not bright enough to view in all conditions, not efficient enough to get you through a whole day or accurate enough to display your favorite content, the experience of the whole device suffers. Choosing the right display technology is certainly a critical part of the design process.
OLED technology’s power consumption and saturation issues have been well established already. What I find most interesting in Tim’s comments is the idea that high color saturation is intrinsically a bad experience. It certainly has been that way so far but the difference between a great color experience and the gaudy oversaturation of today’s OLEDs is in exactly the kind of implementation details he’s describing above.
OLED and emerging LCD technologies, like quantum dot displays, can actually show a much wider range of colorsthan today’s devices– over 40% more of the color that our eyes can detect. This means that, when paired with the right content, high saturation displays can more accurately reflect the world we see around us resulting in a more lifelike, immersive experience.
But how do we get wide color gamut content into consumers hands?
It’s a lot like the chicken and egg/content and technology dilemma facing 4K TV makers with two key differences- wide color gamut can be delivered with no change in file size and there’s plenty content out there already. As an example, movies have been shot for decades on media, both film and digital, that has a much wider color gamut than your TV does today. Much in the same way that 4K TV’s can upscale HD video, it’s also relatively easy to manage the color on a device to make it backwards compatible with today’s content.
OLED implementers have thus far been content to take advantage of the extra pop that added color saturation provides when comparing devices on a store shelf. They’ve left a tremendous amount of overall ecosystem value on the table. It’s possible to deliver video in cinema-level color quality to mobile devices, to offer developers the tools to take full advantage of a wider color palette and to implement accurate color management for existing content. Wide color gamut is ready now, it’s just waiting for the right device maker to come along and put all these pieces together to perfect the experience.
Ken Werner of Display Central has a post comparing the benefits of quantum dots to OLEDs in consumer TV applications. Being the authority on quantum dot displays that we are here at Nanosys, Ken contacted us for an analysis. Here is the explanation our Ph.Ds gave Ken:
OLEDs use organometalic compounds to emit light. They typically have a central metal atom surrounded by organic ligands. The decay issues are the same as with typical organic fluorophores. In the excited state these molecules are very reactive to H2O and O2, as well as other small molecules that may be around. Once they react they become a different molecule and they will no longer fluoresce or phosphoresce and give off light. The more blue the light emission, the higher the energy of the excited state, and the more reactive the excited molecule will be. So your blue organic phosphores will have a much shorter lifetime than will red phosphores. The burn-in problem seen in OLED displays, that can be seen after just several weeks of operation with static content, is a manifestation of early blue degradation compared to green and red.
Conventional phosphores like YAG are doped materials. YAG used in white LEDs is actually cerium doped YAG. The cerium atom emits the yellow light and is surrounded by a vast amount of YAG. Quantum dots are similar in that a central core crystalline semiconductor material is used to confine the holes and electrons of the exciton (analogous to the cerium in YAG), and in our material this is surrounded by a thick shell of a different, lattice-matched semiconductor material (analogous to the YAG.) We call this a core-shell Quantum Dot structure. If the lifetime of our materials is less than that of conventional phosphors, it is typically because we have not made a perfectly lattice-matched shell, which may distort the core and cause defects at the core/shell interface that reduces the quantum yield.
The big difference here is that a perfectly made core-shell quantum dot does not have an intrinsic lifetime failure mechanism, whereas the organometallic compounds are intrinsically reactive to their environment, which makes them prone to shorter lifetimes especially at higher energies such as blue.
A new report from DisplaySearch today shows that TV-sized OLED panels remain prohibitively expensive to manufacture. According to their data, AMOLED price premiums over LCDs range from 30% for smartphone-sized panels to an order of magnitude greater for a 55” TV-sized display.
AMOLED TVs make great tradeshow demos but the data continues to prove the technology is more vaporware than a viable consumer product in the TV space. With major quality improvements coming for LCDs like 8K resolution, higher dynamic range and wide color gamut, AMOLED faces an uphill battle in the race to become the display technology of the future.
A recent DisplaySearch report reveals that manufacturing issues continue to plague OLED TV production. The analyst firm writes:
Coming into July, mass production of OLED panels is not ready, and 3Q panel production means completed OLED TV set starting timing will be Q4’12 at best.
This information has lead DisplaySearch to revise down its OLED forecast from 50k units to just 20k produced in 2012.
Since the market is determined by supply in the short term, the lack of timely supply means that the potential market of 50K units in 2012 is not possible.
Even this lower projection may prove too bullish. If complete sets do not start rolling off assembly lines until Q4 ’12, OLED makers have very little room for error to move a significant volume of units by the end of the year.
An even bigger problem for OLED technology might be that LCDs are continuing to provide stiff competition. In the same report, DisplaySearch highlights the “dynamic, extremely competitive” nature of LCDs:
The other factor, of course, is that the incumbent technology is dynamic and extremely competitive in terms of value and price. 60” LED-backlit LCD TVs are expected to fall to $999 for Black Friday, while 70” and larger sizes will likely be available at aggressive pricing as well. LCD TVs using oxide TFTs may be available in 4K x 2K format could also have a big impact on 55” OLED TVs when they are launched. Just as in smartphones, where Apple has used high resolution LCD to compete with Samsung’s AMOLED phones, consumers could see contrast ratio and high resolution as offering greater benefit.
CES 2013 should be an especially interesting indicator for the future of TV panel technology, as we will have a clearer picture of what OLED makers can deliver, while LCD makers drive down price and introduce new sets with higher resolution, deeper blacks and wide color gamut.
