Display pixel density: Where 'more' is not necessarily 'better'

Display pixel density: Where 'more' is not necessarily 'better'

Summary: While beating the iPad 3's pixel density might look good on the box or in press releases, in the real world it can have a negative effect on performance and battery life.


Apple's iPad 3 retina display screen already has pixels so small that they human eye can't make them out. Going any denser than this is pointless.

Apple's iPad 3 has a screen density of 264 pixels per inch (PPI), but Google is rumored to be unveiling the Nexus 10 nest week, a tablet that could push the PPI count as high as 299, well beyond what the human eye can make out.

While this number might look impressive on paper, and allows Google to claim a win over Apple and the iPad 3, in the real world it is nothing to get excited about. In fact, unless you hold the screen real close to your face, or you spend time examining it with a magnifying glass, you're not going to be able to tell that it has more pixels per inch than the iPad 3.

There's also a downside to boosting screen density to beyond what the human eye can make out. The tablet's hardware has to pump those pixels to the screen whether your eye can make them out of not, and the system resources used to do this could better be spent doing other things.

Not only do the extra -- and redundant -- pixels put an unnecessary strain on the GPU, the extra load of the screen and GPU zaps battery life at a faster rate, meaning that your tablet will need recharging more often.

All these downsides just so marketing can get one up on Apple.

The bottom line is that when it comes to tablets, anything over 250 PPI is a retina display, and the pixels are too small to be seen individually. Boosting the figure beyond this might look good on the box and in press releases, but in the real world it can have a deleterious effect on performance and battery life.

The iPad mini and the new iPad 4

Image source: Google.

Topics: Tablets, Android, Apple, Google, Hardware, iPad

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  • So for apple it was good now that iPAD 3 is going to lose it became

    You know you are a fan boy it don't you?
    • Not what he is saying at all

      Apple hit the point where any more pixels per inch would not do you any good. So they basically reached the point where adding any more is just a waste other than to say they beat Apple at something. But all else being equal, it has to reduce battery life and it also has to increase cost. So it will have less battery life and higher cost than it otherwise would with no practical benefit to the user.

      We will have to see how it turns out in the real world but specs just for the sake of specs are meaningless. BTW, if it matters I'm a Transformer user and own no Apple stock or Apple products.
      • And more amusing

        The surface is reputed to have a pixel density of 148 ppi compared to 264? for the iPad and 299 now for the Nexus. And lo, all three are or will be claiming their display's are the best, the clearest, will make your tea for you and kick the neighbour's dog for good measure. What a bunch of plonkers.
  • You're kidding, right?

    How is not being able to see the pixels a bad thing? Straining the GPU? It's not like it's using the toilet! And what about pinch and zoom?

    The closer displays get to print quality, the better it is for everyone. If it means less battery time, so be it. It's not like I need to be on the thing 24x7. My eyes will thank me later.
    • LOL

      You said pinch and toilet in the same comment.
      Loverock Davidson-
    • Pinch & Zoom?

      What does that have to do with screen resolution? You're thinking of image file resolution. And are you suggesting that low-res graphics are hard on the eyes?
  • 300 ppi a good target.

    Surely with the printed page often being 300dpi, aiming to match that on a display is a good thing to aim for!?
    • Re: 300 ppi a good target.

      Yeah, I'd agree with that. I thought it was only a technical limitation that tablet-sized panels had lower pixel densities than phone-sized ones.
    • PPI vs. DPI

      PPI and DPI aren't the same thing, but, yeah, 300 DPI is basically the minimum requirement for printing (and it goes much higher). The traditional difference between screen and print resolution is often mentioned as the reason for eye strain.

      Beside, GPUs pump pixels very well and efficiently.
      Bo Dangren
  • Finally, a journalist gets it.

    I would say slightly more than 200dpi is the useful upper limit.

    What we want is more dots, not more dense dots. More dots mean more information can be carried. Unfortunately, it means a bigger screen if the DPI is lower.

    So the starting point should be the physical size you can bear. Then multiply it by 200 and that's the maximum you should get.
  • srsly?

    nice article btw, this comment is about the 9 ''smart ones'' are you out of your mind? from when the display quality had to do with the printing quality???? it's like you all are saying that if i took a picture with a 1MP camera and put it to iphone 3G and then to iphone 5 cuz of the deference on the display the picture when i am going to print it will be better.... are you all insane or something? the quality of the picture has to do with the camera and only with that, it doesnt matter if you have a phone with 1million ppi screen, while having only 1MP camera, the photo with be still on 1MP quality, but if you have 100 ppi screan with 15MP camera, the photo that will be out of a printer will be on 15MP!!! juses, all the ppl became experts while having less than 90IQ