Smartphone and tablet maker HTC just announced its new top-of-the-line Android phone, the HTC One. In a world where every maker of phones that carry Google’s Android mobile operating system must differentiate from each other based solely on hardware, HTC’s strategy is apparently to go for broke with the most monstrous technical specifications possible. This had better work: HTC is ailing, and it’s counting on a hit phone to revive its fortunes.
One of the most impressive specifications of the HTC One is its screen, which has the same resolution as a high definition television, 1920 by 1080 pixels, but is just 4.7″ across the diagonal. Let me put that another way: Imagine taking a 42″ HD TV off the wall and magically shrinking it to the size of a smartphone.
The trouble is, it’s not clear that this matters. Owing to the limits of human visual acuity, a screen with the resolution of the HTC One’s implies that the average user is going to be holding their phone about a half foot from his or her face. Any further away, and you’d miss out on the full awesomeness of it.
Here’s the math.
How pixellated a screen looks to the human eye is captured by a measure known as “pixels per degree.” PPD includes both the screen’s actual resolution and how close it is to your face. Apple defines its “Retina” displays as having at least 53 PPD; any more than that, and the eye supposedly can’t even detect the pixels, i.e., the display looks perfectly smooth. (Based on my own experience reading tiny text on Retina displays, I’d say the value could be even lower.) So how do the iPhone and the HTC One square up on this score? If you want to follow along at home, here’s a handy PPD Calculator.
4 inch screen (diagonal)
1136×640 pixels resolution (16:9 aspect ratio)
Apple picked 10 inches as a “typical” viewing distance
= 57 PPD
4.7 inch screen
1920×1080 pixels (16:9 aspect ratio)
57 PPD (chosen to match our measures of the iPhone 5)
= implied viewing distance of 6.97 inches. (With a PPD of 53, the supposed visibility threshold, it’s even shorter, at 6.48 inches.)
This is roughly the distance from the tip of your thumb to the tip of your forefinger, when held at right angles. So put your thumb to your eye, stick out your forefinger, and put your phone where the tip of it is. Comfortable?
In other words, unless you’re holding your new HTC One so close to your face that there is barely room enough for you to put your thumbs on it without poking yourself in the eye—and so close that, unless you’re pretty short-sighted, you can’t even focus on it—this extra-high resolution is completely wasted.
So will a phone with such a screen as its major selling point capture enough of the nearly-saturated market for high-end Android phones to revive HTC’s business?