Full HD displays in premium handsets are a regular sight amongst hardware spec tables, and companies are often keen to tout their display as the next big thing when when you look at a manufacturer’s website. Currently, LCD tops the table as the most commonly used technology when it comes to HD screens. You’ll find one in the 4.8-inch HTC One, 5-inch Sony Xperia Z, ZTE Grand S, OPPO Find 5, the 5.5-inch LG Optimus G Pro, and Lenovo Ideaphone K900.
You’ve probably heard of AMOLED displays before as well, in fact the smartphone you’re using right now could well have an AMOLED screen. The popular Galaxy S2 and S3 both use lower resolution AMOLED displays. Currently, technological barriers prevent manufacturers from producing 1080 HD versions.
However the Samung Galaxy S4 is set to be the first smartphone released using a Full HD AMOLED display, bringing the technology up to par with LCD smartphones, at least regarding pixel density.
The visual difference between AMOLED and LCD mostly boils down to individual preference; darks are better on the former, but LCD has a more natural contrast. Whilst one technology isn’t obviously better than the other, the important thing is that AMOLED is now ready to give consumers more choice, as it can finally take on HD LCD displays head to head.
Click to enlarge pictures of Samsung’s flagship Super AMOLED displays
Making the move to Full HD AMOLED
Previously, reaching a pixel density greater than 300ppi has been the problem when producing Full HD AMOLED displays. This is due to the Fine Metal Mask processes used to produce the screen, designers have to balance the number of pixels against display brightness and power consumption. Unfortunately it’s just not possible to cram in enough pixels without draining the battery.
But thanks to some clever technical tweaks made by Samsung, the switch to 1920 x 1080 AMOLED displays is now possible. By making use of an entirely new Pentile matrix for the pixel arrangement and phosphorescent materials for OLEDs (PHOLEDs), Samsung has overcome the pixel density and battery consumption issues.
Samsung’s new pixel arrangement tweaks the layout of the screens subpixels slightly from the Pentile arrangement used in the Galaxy S3. According to the information we’ve seen about the Galaxy S4’s screen, the use of larger green subpixels in a diagonal shape reduces the number of green subpixels required to produce the same image. This means that you can either reduce power consumption by using fewer subpixels whilst keeping the same resolution, or allows you to squeeze more pixels into the same space, increasing the resolution of the display.
Changes to Samsung’s subpixel layout.
PHOLEDs are also an important aspect of the new design. PHOLED technology uses phosphorescent materials in order to reduce the power required to produce light, but they don’t tend to last as long as regular OLEDs. For this reason Samsung has chosen to use only green PHOLEDs in its new screen, balancing power consumption and screen life expectancy. Combining this with the new pixel arrangement, which reduces the number of green subpixels, you can see how the significant energy savings are made.
Now that Full HD AMOLED screens are available for production we should see the technology start to be taken up by various manufacturers. According to technology research firm IHS, high-quality AMOLED display sales are expected to double by the year 2017.
In terms of raw numbers that puts expected AMOLED display shipments for mobile handsets at around 447.7 million units in 2017, a pretty substantial growth from the 195.1 million units expected to ship in 2013.
Director for mobile and emerging displays and technology at IHS, Vinita Jakhanwal, had this to say about the future of AMOLED:
“Because of their use in marquee products like the Galaxy S4, high-quality AMOLEDs are growing in popularity and gaining share at the expense of LCD screens.”
So IHS expects some of the growth in market share to come from LCD displays, which is an analysis I deem highly likely given LCDs current prevalence in the HD smartphone market. Rather confusingly though, IHS predicts that AMOLED’s market share will mainly increase in devices using smaller display sizes.
The company predicts that AMOLED’s total smartphone market share will increase from 7.9% to 15.2% over the next 4 years, but will only grow by 1.4% in handsets using 4-inch or larger displays, only slightly improving from 23% this year to 24.4% by 2017.
IHS’s prediction for larger displays seems rather subdued, by there are still some issues with screen lifetimes, color balance, and limited production capabilities which it believes are still prohibiting AMOLED displays from stealing a more significant share of the LCD market.
To conclude, AMOLED is now a better technology than ever and the Galaxy S4 will be the first in a line of smartphones making use of Full HD AMOLED displays. This direct competition with LCD displays for screen resolution will certainly help to improve AMOLED’s market share, but there’s a large sales gap between the two display technologies to make up.