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.”

Over at the NASA Ames Research Center, Andrew B. Watson, Senior Scientist for Vision Research said in an email interview that he was pleased that Apple had dubbed the new screen the "retina" display and emphasized that the company was trying to match the display to the requirements of human vision. “That is our mantra, and as a vision scientist, I felt flattered. However, I was slightly skeptical about the claims (Jobs) made.”

Watson, whose work involves developing display metrics that are meaningful to the human eye, looks forward to the day when visual resolutions are quoted as a display spec. He explains that in order to know the true effective resolution of a display, you need to know not only the resolution in pixels/cm, but also the viewing distance. Together these give you the true "visual resolution" of the device in pixels/degree.

Resolution is one of the key contributors to the users' quality experience when using a device display, according to Watson, the benefits provided by high resolution depends somewhat on the content you’re viewing--for example, you’d notice high resolution more in images with sharp edges such as text.

“And with resolution, there is a point of diminishing returns. From a theoretical point of view, the absolute limit is around 120 pixels/degree. But it becomes progressively harder to tell the difference above 60 pixels/degree, a visual resolution is reached at a viewing distance of about 27 cm (around 10.6 inches), which is a reasonable natural distance for an iPhone,” said Watson.

Besides pixel density, the most critical factors in creating a great display for a small gadget like the iPhone include color gamut (the total space of colors that the display can produce), field of view, and contrast ratio (the ratio of brightest to darkest pixels). That latter, Watson said, is an area of raging controversy.

“Nowadays, contrast ratio mainly has to do with how black you can make a pixel, which is ironic. Another is brightness, up to a point. And another is how well the screen suppresses reflections, although this may be less important for handhelds, where you can rotate the screen to avoid reflections.”

Watson added that not all quality limits are imposed by small-sized display form factors. We have, he points out, a digital infrastructure that is hard to change. For example, it’s conventional to code each pixel signal with 8 bits each for red, green, and blue, but that is simply too small a space to achieve high dynamic range displays.

“To some extent, current displays are already reaching the limits imposed by the eye and the infrastructure. Future developments will probably be in making displays cheaper, lighter, lower power, or extending them into new domains such as creating flexible, 3D, immersive, wearable, integral, or holographic displays,” said Watson.

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