In yesterday's iPhone 4 announcement, Steve Jobs shoveled a lot of specs at us, particularly regarding the new "Retina Display
." The oddly-named screen - an LCD with a pixel density abnormally high for a mobile phone - seems like it will be one of those features, like the iPad's display, that you have to see to appreciate. The iPad was not that impressive when it was first announced, one may remember, but many people were blown away by the screen when they actually saw it with their own eyes.
The Retina Display's name seems to be either a conscious or unconscious riff on the retinal displays used in virtual reality
, where pixels are projected directly on the retina. Steve Jobs also made mention of the fact that the human eye can only discern individual points of light at a density below 300 pixels per inch. This screen, with its pixel density of 326 ppi, is thus supposedly to be as lifelike as a photograph.
Additionally, the Retina Display employs the same IPS (in-plane switching) technology used in the iPad and Apple LED Cinema Display. With IPS, the crystals are aligned horizontally to the screen rather than vertically, which keeps the crystals parallel to the screen. With normal TFT screens, the crystals turn at right angles relative to the surface, which limits contrast, brightness and color definition as you look at the screen from an angle.
This screen also has a much higher contrast ratio: at 800:1, the Retina Display has a 4x greater ratio between the darkest black and the brightest white than the current iPhone. This will give improved detail in dark images and videos, and make text display even sharper when combined with the high pixel density.
Apple says the glass on both the front and back of the iPhone is "Made from the same materials used in helicopters and high-speed trains" and "chemically strengthened to be harder, more scratch resistant, and more durable than ever." We'll have to wait and see, as I'm hard enough on my plastic iPhone... however, "harder than sapphire crystal" is an impressive brag.
So I still think "iPhone HD" might have been a more appropriate name for this device... but given the number of superlatives Apple is tossing around in their marketing, having it be called just a plain old "Four" takes a bit of the bombast out of it.