Samsung Gets Down to the Nitty-Gritty With Super-Sharp Tablet Display
Samsung says it's created a 10.1-inch display with an ultra-sharp 2,560-by-1,600 pixel resolution. The screens could become standard equipment on tablets from a variety of manufacturers by the end of the year. Super-sharp displays are common on smaller gadgets like smartphones, but building them for the specific needs of a tablet is a different game.
May 16, 2011 6:00 AM PT
Samsung Electronics will demonstrate the first 10.1-inch tablet with a WQXGA PenTile screen at the SID Display Week symposium, to be held in Los Angeles May 17 to 19. The display offers a resolution of 2,560 by 1,600 pixels.
The screen's resolution translates to 300 dpi, not too far behind the 326 dpi offered by the iPhone's Retina Display screen.
Announcing the display, Samsung said it will be commercially available on tablets later this year.
Samsung Electronics declined comment when contacted by TechNewsWorld.
About the WQXGA PenTile Display
Samsung's WQXGA PenTile display technology consumes 40 percent less power than legacy RGB stripe LCD screens in power saving-modes, according to Samsung. It enables viewing in bright ambient lighting.
QXGA stands for Quad eXtended Graphics Array. WQXGA technology is already available in larger screens, such as the 30-inch Dell 3008WFP and the Apple Cinema Display.
The Samsung 10.1-inch WQXGA display has a 72 percent color gamut, compared to the typical 55 percent offered by RGB stripe tablet displays, Samsung claims. This lets it display colors more realistically than legacy displays.
A gamut is the subset of colors that can be accurately represented within a given color space or by a certain output device.
What's a PenTile?
PenTile technology uses subpixel layouts consisting of five pixels arranged in a quincunx. A quincunx is the five-spot pattern you see on dice, playing cards or dominoes. The PenTile quincunx consists of two red subpixels, two green subpixels and one central blue subpixel in each unit cell.
Invented by Candice H. Brown Elliott, PenTile technology was licensed by Clairvoyante from 2000 to 2008. Samsung Electronics bought Clairvoyante's PenTile IP assets in 2008, then funded a new company, Nouvoyance, to continue working on the technology. Joel Pollack, who used to be CEO of Clairvoyante, is a senior vice president at Nouvoyance.
PenTile technology uses the same number of pixels as a legacy stripe panel but only two-thirds as many subpixels. This lets Nouvoyance make the subpixels larger and allow more white space between the subpixels, which lets more light pass through.
Subpixel rendering technology and adaptive filtering algorithms enable PenTile to reduce the number of subpixels it needs.
"There is a great deal of know-how in the engineering of this panel," Nouvoyance's Pollack told TechNewsWorld. "There are many algorithms for subpixel rendering, adaptive filtering, sharpness enhancement and dynamic backlight control."
"There are three benefits to using a PenTile arrangement in a display," Dmitriy Molchanov, an analyst at the Yankee Group, told TechNewsWorld. First, displays become cheaper; second, they last longer; and finally, using PenTile displays makes for longer battery life because they consume less power.
More than 70 products in the market, including smartphones and digital still cameras, use PenTile technology, Pollack pointed out.
Complaints About PenTile
PenTile technology hasn't always well-received.
The Google Nexus One smartphone's PenTile screen was criticized because the pixels looked fuzzy.
"Images using PenTile appear grainy because you're using fewer subpixels," the Yankee Group's Molchanov stated.
Why a High-Res Tablet Display Only Now?
Back in June, Apple unveiled the iPhone 4 with its Retina Display. It followed that with a Retina Display on the iPod touch in September.
What took screen manufacturers so long to come up with a higher-resolution display for tablets? It should be easier to pack more pixels into a larger screen, shouldn't it?
"A tablet display has more demands than a phone display because it requires the color accuracy of TV and the power savings of smartphones," Nouvoyance's Pollack remarked.
Moving to a high-resolution degrades the aperture ratio of the subpixel, reducing the amount of light available from backlighting, Pollack explained. Resolving the technical problems required a number of technological innovations.
WQXGA for the iPad 3?
There's speculation that Apple might use Samsung's new WQXGA display in the iPad 3, but that's unlikely for two reasons, Rob Enderle, principal analyst at the Enderle Group, told TechNewsWorld.
First, the two companies are locked in litigation.
Apple filed suit against Samsung in April in the U.S. District Court of Northern California, claiming that the Korean firm's Galaxy line of cellphones and tablets violate its patents and trademarks by closely copying the designs of its iPhone and iPad. Samsung is fighting back.
"Samsung is one of Apple's largest suppliers, but with this litigation going on, it's going to be harder for Apple to source this display from them," Enderle remarked.
Second, Samsung might want to retain the right to sell the display freely.
"Apple likes exclusives, and it likes to tie up its suppliers," Enderle stated. "But Samsung's got its own internal customers for this product and might not want to do that."
It's likely that Samsung will sell the display to any tablet manufacturer that wants to purchase it, Enderle added.