Apple iPad Display Shoot-Out: Apple iPad Retina Display vs. iPad 2, iPhone 4 (Introduction)

Our Ray Soneira, one of the world’s leading experts in display tech, previews his upcoming new Apple iPad comparison with the Apple iPhone 4 and the Apple iPad 2. Soneira’s lab, DisplayMate, is set to reveal its findings on how the Apple iPad third generation compares shortly.

In a few days, I’m releasing lab results comparing the new Apple iPad third-generation tablet display with those of the Apple iPad 2 and iPhone 4.

That means detailed laboratory measurements and extensive viewing tests with both test patterns and test images.  Shown below is a comparison of how the iPad 2, iPhone 4 and Samsung Galaxy S OLED compared in our test of relative handling of RGB spectra. We’ll be adding the new Apple iPad third-generation tablet and its Retina display to these results right here shortly.

We have already done extensive tests comparing the Apple iPad 2 against most leading displays in the market — and we’ve taken an in-depth look at the Apple iPad 2 display in our laboratory tests. These are some revealing screenshots. It will be interesting to see how the retina (or near-retina) display of the new Apple iPad 2, with its more intense pixel density and resolution, stacks up. We’re preparing those results now.

We’ve already noted in our studies the huge strides in display technology Apple brought forward with its iPhone 4. Look at these magnified photos — showing what happens when you send a beam of light at each display — and how differently the higher-res and higher quality iPhone 4S reacts. We made the iPhone 4S display of the year in 2011. For the full report, check out our lab site with results here.

The screen is the main reason many survey respondents in, now, dozens of surveys, say they are eager to buy the new Apple iPad.

At the March 7, 2012, new Apple iPad launch CEO Tim Cook remarked that people have been wondering who would improve upon the iPad. It’s the display. Makes sense. Tablets are, after all, essentially large portable displays. So a top-notch display is the key to a successful product  — that is something most manufacturers haven’t figured out yet. In our upcoming tests, we will see how its new “retina display” measures up. In the meantime, here’s a little background.

The Apple iPad third-generation tablet is not an actual retina display.

The original retina display on the iPhone 4 has 326 pixels per inch (ppi). But to qualify as an Apple Retina Display, the new iPad does not require the same ppi as the iPhone 4 Retina Display. That’s because you typically hold it further away from the eye, so visual sharpness is based on angular resolution rather than the linear ppi resolution on the display.

The iPad is typically held 15-18 inches away from the eye as opposed to the iPhone 4’s 12-15 inches. As a result, to meet the 300 ppi Retina Display specification made by the late Steve Jobs himself at the World Wide Developers Conference about the Apple iPhone 4, an iPad Retina Display only needs 240 ppi to qualify. The new Apple iPad display has 264 ppi. So, according to Apple’s own definition, the new iPad is indeed a true retina display.

The discrepancy between Retina Display as a marketing term versus a scientific term.

Here’s the distinction.

Apple defines “retina display” for those with 20/20 vision, which researchers define as 1 arc-minute visual acuity or “normal vision.” This is actually at the lower end of true normal vision.

There are in fact lots of people with much better than 20/20 vision. And for almost everyone, visual acuity is actually limited by blurring due to imperfections of the lens in the eye. The best human vision is about 20/10 vision, actually. That’s twice as good as 20/20 vision — and this is what corresponds to the true acuity of the Retina.

To be a true retina display so far as the scientific definition goes, the new Apple iPad screen would have to be at least 573 ppi at 12 inches viewing distance —  or 458 ppi at 15 inches.

Now, the 326 ppi iPhone 4 is a 20/20 vision display if it is viewed from 10.5 inches or more. But a 20/20 vision display doesn’t sound anywhere near as enticing as the term Retina Display. That’s why marketing and science don’t see eye-to-eye on this.

Do you really need all of that resolution and sharpness?

As you will see in my upcoming display test comparison, the new iPad display is incredibly sharp with 264 ppi and 3.1 million pixels on a 9.7-inch screen. The iPad 2 screen with 132 ppi, a resolution of 1024 x 768 and 0.8 million pixels is noticeably pixelated in comparison.

But did Apple really have to double the resolution and, in doing so, quadruple the number of pixels inside? Marketing considerations aside, the real reason for doubling the iPad’s resolution to 2048 x 1536 is for the convenience and ease in up-scaling the older 1024 x 768 apps from the iPad 1 and iPad 2 – consider that every existing iOS app previous to iOS 5.1 is simply replicated 2×2=4 times. Rescaling to lower resolutions like 1600 x 1200 would have required more complicated processing. But the high power A5X processor (a dual-core, 1GHz chip with a quad-core GPU on board) could easily have handled that.

As we prepare our display tests for you, note the following.

1. Most adults don’t actually have true corrected 20/20 vision, even if they wear glasses.

2. If you view the display further away than the recommended viewing distance your eye can no longer fully resolve the sharpness of the display, so you are not even seeing the benefits of this so-called high resolution.

3. Unlike computer graphics images, photographic images (including videos) are inherently fuzzy, with the sharpest image detail spread over multiple pixels. Similarly, you would be hard pressed to visually tell the difference between 640 x 480 and 2048 x 1536 photographic images of a (Granny Smith) Apple. Watch for a comparison on that.

4. Sub-pixel rendering, rather than ordinary pixel rendering, significantly does improve the visual sharpness of any display, especially for computer-generated text and graphics. So that is the most efficient approach to improving sharpness.

5. Most people don’t even have 1600 x 1200 resolution on the much larger 15-19 inch screens on their (Apple or Windows) laptops and desktop monitors — though some of our reporters’ sources say that is coming soon to the Macbook Air and other displays.

So where will the 2048 x 1536, 3.1 Mega Pixel Retina Display actually make a noticeable visual improvement over other displays?

Whenever there are tiny on-screen text and fine graphics, which you often see when surfing the web — say, you’re reading The New York Times on it or digging into a detailed spreadsheet — you’ll see a tremendous visual difference between the new iPad and the iPad 2. You won’t have to zoom in as much or switch to landscape mode as often when reading tiny web content.

The larger tablet format will also make the iPad appear visually sharper and more stunning than the much smaller (and higher ppi) iPhone 4.

One final note on retina displays: Your existing HDTV is already a Retina Display. For example, a 1080p, 46-inch TV viewed from 6 feet or more and a 1080p, 60-inch TV viewed from 8 feet or more (the typical TV viewing distance in the US is 9 feet) is already 20/20 vision “Retina Displays” so don’t worry about upgrading them to get Retina Display resolution and sharpness. Watch for our upcoming review.

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  • Great review.

    One thing that I think people forget though is visual blending. Designers deal with it constantly when selecting DPI vs. print size. If an advertisement is viewed from a distance, the designer can use less DPI (Dots per inch, but it is comparable to PPI or pixels per inch) since people’s eyes will visually blend the ink dots and registration.

    A similar to print, PPI on screen is also effected by how far you are viewing your content from. A lot of these up comparisons of the iPad Retina Display vs the traditional screen resolution aren’t entirely accurate. No one is going to be viewing their iPad from a few inches away. iPads and other tablets are held at a comfortable reading distance. I think people forget to take this into consideration when readings reviews and comparisons.