Size is a critical dimension for consumers to consider when buying a product with a display. Will this TV fit on my wall? Would this tablet fit in my jacket pocket? How much picture am I getting? To guage displays today, we take a diagonal measurement of a 16:9 rectangle. This leaves value on the table. Not just because consumers are notoriously bad at math, it fails to capture the full value of the increase. As display industry analyst Bob Raikes said:
A display that has twice the diagonal (and the same aspect ratio) has four times the screen area. Would Intel describe the clock speed of its CPUs by giving them a number that is the square root of the clock speed? If Intel went from 1GHz to 2GHz, would the company really give customers a number that is just 40% bigger? Ah, we’ve gone from 1 IntelMark to 1.4 IntelMarks. No chance!
Why would we say “twice” when the real value increase is “four times”? This is especially relevant as consumers shop more online. Although size may be apparent in a brick and mortar showroom, it is not easily conveyed online. Take a look at this image- which tablet is bigger? By how much?
Apple’s Phil Schiller demonstrated this yesterday at the iPad mini announcement. The new iPad mini is only 0.9 inches or 12% bigger than a Nexus 7 on the diagonal, he says, but it is actually 35% larger by area. This is another example of display marketing efforts starting to move beyond PPI comparisons. Product and display marketers: let’s get real about the value we’re adding – whether it’s surface area or color. Let’s stop leaving value on the table.
This is a great, exhaustive tutorial on managing color gamut for photographers by color expert Andrew Rodney. He does a great job making the case for working in wide gamut color spaces like Pro Photo, especially when capturing in RAW. Using smaller gamuts like sRGB throws away useful color data that printers and more and more displays can recreate.
We typically focus on color as it relates to displays here at dot-color, but I came across a fascinating post about color in the print industry from John the Math Guy that I had to share. In this post, John takes a close look at how ink looks at different thicknesses and uncovers the reasons for some seemingly unconventional color-naming habits in the print industry.
What happens when we double the amount of ink on the paper? …it would seem that the thick layer of magenta is a lot closer to red. The plot below shows the actual spectra of two magenta patches, one at a larger ink film thickness than the other. The plot leads one to the same impression – that a thick layer of magenta is closer to red in hue than a thin layer.
Chart shows different spectrums of thick (red line) and thin (blue line) layers of magenta ink.
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.