Motorola Droid X2 Review - A Droid X with Tegra 2by Brian Klug on July 7, 2011 8:31 AM EST
Display - qHD RGBW PenTile
Probably the most significant change (other than Tegra 2) between the X and X2 is of course the display. As we mentioned before, that has been upgraded from a 4.3” FWVGA (854 x 480) IPS LCD to a qHD (960 x 540) LCD with the same diagonal size. What’s special about the X2’s screen, however, is that it comes with an RGBW PenTile subpixel rendering layout.
We’ve talked about the RGBG PenTile subpixel structure before in the context of devices which came with AMOLED or Super AMOLED displays. The chief complaint back then was that black text on webpages and UI elements didn’t always look super sharp. RGBW is a different layout with different purpose, and dare I say different results.
As its name implies, RGBW PenTile includes a fourth, white, subpixel. The idea here is that light throughput for the panel can be vastly increased by simply adding a subpixel with no color filter. That increase in throughput then can be exploited to either get equivalent visual brightness with less backlight power, or you can crank things up all the way and get extreme brightness for the same backlight power. That translates to power savings most of the time, and extremely bright whites other times when you need it. It actually does make a lot of sense, especially when you consider things like browsing webpages which is still largely black text on a white background.
On webpages, RGBW actually looks pretty good, with black text being nice and sharp on a white background. This is one place where RGBG just never could do a perfect job, but RGBW does. I actually have no problem with RGBW for black text on white backgrounds.
The only place you can still dramatically tell that this is PenTile is either by looking at regions that are solid green, or red. At green in particular, you can see a bit of that grain from the subpixel structure - green is most visible because visual acuity peaks in the green. Red is also sometimes also shows a bit of that telltale grain, but nothing too dramatic. Human visual acuity isn’t very good for blue, so that looks pretty homogeneous.
In our tests, the X2 results definitely show how much having that white subpixel can help.
Motorola has had a pretty steady track record for putting great displays in their devices, going all the way back to the original Motorola Droid which included an IPS display. It’s nice to see that they haven’t compromised with the X2 either.
We’ve also been measuring display brightness and white point at 25% brightness increments on displays lately, and the X2 is no exception from this treatment. Alongside the Motorola Droid X, the X2 looks substantially bluer. Looking at the white point on the X2 it’s easy to see where that comes from. At 7500K it’s closer to sanity than the 8500K for Super AMOLED Plus, but still not quite perfect.
Moving onto the brightness (white and black) graph, we can see something finally reminiscent of a LCD, showing steady contrast as black and white both climb in a nice linear fashion as we ramp up brightness. The Droid X2 stays pretty contrasty, moreso than we originally measured the Droid X as being, but still not quite chart topping.
Viewing angles on the X2 seem subjectively better than the original X. You can see colors on the X fade off and turn strange at the extreme vertical angles and a bit as well at horizontal extreme angles. I don’t remember the X looking this bad, it could be that the device I borrowed has a worse panel than the original X we were sampled last year.
Outdoors the X2 seems pretty readable, no doubt thanks to having that white subpixel and extremely high brightness. Even in the extremely bright, direct Arizona sunlight the X2 seemed a bit more readable than other devices from recent memory.
Again the real nice thing about the X2 display is that qHD resolution which makes it able to both have a bit more text smoothing on webpages, and also just look better. I was especially thankful for that extra resolution when using things like remote desktop and maps from the X2, as a result, things on similarly sized WVGA displays look cartoonishly huge.