The Truth Behind the iPhone 4 Retina Display

Thanks to his ability to restructure the time-space continuum in accordance with his will, Steve Jobs normally gets away with pushing the credibility barrier a bit during product launches. But when he recently announced that the iPhone 4 sports a “Retina Display,” questions were raised. Were those tiny little pixels really so small that, when the iPhone 4 is vigilantly held a particular number of inches in front of your nose, the human eye cannot detect them? Calculators were whipped out, numbers were crunched, and experts batted about their sometimes-opposing views. We sorted through all the noise, interviewing key players (via email) to bring you the definitive answer. And that answer is: close, Steve, but no cigar.

But the really important question isn’t whether Steve’s math is perfectly correct. No, the more germane question is whether an ever-growing plethora of teeny-tiny pixels really matters in the greater scheme of things. Do more pixels equate to a better gadget experience for users? Are these little red-blue-green dots the holy grail of mobile displays--and if they are, can we trust companies to provide us with accurate specifications?

The math discussed in media stories and blog posts about the iPhone 4 was enough to give many of us brain cramps. Nonetheless, others were inspired to jump right in and wrestle with the numbers to extrapolate real-world usage data. Among them was Phil Plaits, a scientist who spent a few years calibrating a camera on board the Hubble Telescope and who now blogs for Discover Magazine.

“My first reaction to the announcement and the ensuing coverage was interest and curiosity. I figured [Jobs] wouldn't lie outright, so what really is the limit of human vision as far as pixel size? The math is simple, if you know it, so I did the calculations, and found that while his claim wasn't perfect, I thought in context it was fine,” said Plaits, who helpfully provides charts and graphs illustrating the central concepts in his blog post about the iPhone 4’s display.

But as usual, the devil is in the details.

“It's easy to make assumptions about pixel size and distance, but then you have to take into account human vision--which is complicated--how the pixels are laid out, whether there is space between them, how they're refreshed, and so on,” said Plaits, who adds that he opted not to worry about slicing the data that finely.

“I just wanted to see if, given some simple assumptions, you could make a smooth, continuous-looking display. The answer is yes, and the new iPhone display will be pretty close to that ideal.“

Some experts, however, say more accuracy is warranted. Dr. Raymond Soneira, president of DisplayMate Technologies Corporation, which produces video calibration, evaluation, and diagnostic products, said that exaggeration over display specifications has been “building for many years and has now become outlandishly unreliable, with many of the consumer specs being exaggerated by 1000 percent or more.”

Blame it on the snowball effect: Once one manufacturer exaggerates its exacting specs a tiny bit, all the competing companies do the same. The stakes are raised again and again, and pretty soon that little innocent snowball has morphed into an out-of-control abominable snowman.

“The manufacturers have actually painted themselves into a corner because the numbers they are quoting now are so ridiculously large that there is nowhere to go,” said Soneira. “The only realistic solution that I see to stop spec abuse is an organization (completely independent of the manufacturers) that develops a set of straightforward objective standards for measuring and advertising display specs for consumer monitors, laptops, HDTVs, smart phones, and other mobile displays.”

Soneira, whose statement about the iPhone 4 display sparked the furor over whether Apple was fibbing about the specs or not, envisions that manufacturers that meet those independent standards would be allowed to advertise their specs with a special controlled trademark, like the EnergyStar program. And consumers would learn to only trust specs with that trademark.

“I proposed this back in 2003, but it went nowhere because too many manufacturers resisted the idea,” Soneira said. “It's time for this solution to be implemented--or just imposed. It's in everyone's interest except for the manufacturers that can only compete using fraud.”

Soneira added that his initial analysis and comments on the Retina Display “were widely distorted and transformed into an attack on Apple and Steve Jobs--they were not. I simply did a quantitative analysis of what was said in the context of my campaign to eliminate (or more realistically, reduce) exaggeration in display specs. Apple's claim falls under glorious wording rather than numerical-spec abuse—and even with quantitative analysis, it's minor compared to what other manufacturers are saying. I sent Steve Jobs an email explaining that and got a reply from him.”