I'm not saying that the iPad's screen is bad, but after owning the iPhone 4 with the Retina Display, you really do notice the difference in pixel density.

我并不是说iPad的屏幕不好，但拥有了配有Retina Display的iPhone 4，你就真的会注意到两者像素密度上的不同。

youdao

This screen is a few millimeters away from your retina, but as long as the focus is right, you can still see a clear picture.

管这种屏幕离你的视网膜之有几毫米远，但只要焦点选择正确，你仍旧可以看到清晰的图片。

youdao

We can see that a Retina iPad screen is a much bigger power hog than a non-Retina screen of the same size.

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Apple relies far more on innovation than invention: the high-resolution retina screen, miniature drives, voice recognition and other technologies in their products were invented by someone else.

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According to iFixit, who recently tore down a MacBook Pro and its retina screen, that's likely related to a design direction favoring smaller, lighter notebooks and longer battery life.

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