Being relatively small, the screen had a resolution of a then-unheard-of 200 pixels per inch (ppi).

一款相对较小的显示器，它拥有一个前所未闻的每英寸200像素的显示屏。

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Every screen has pixels-per-inch (PPI) characteristic. This number tells you how many pixels fit into one inch and thus how large the pixels appear in the real world.

每一个屏幕都有一个每英寸像素(PPI)的特性。这个数字告诉你一英寸显示多少像素，也就是一像素在真实世界里显示的大小。

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The Android-powered handset's screen offers 234 pixels per inch (ppi) which allows it to support 720p resolution video playback.

BBC: Samsung unveils 6.3in Galaxy Mega smartphone

The interesting takeaway is that the Focus 2 has a slightly higher ppi than the Lumia 900 (233 pixels per inch vs. 217).

ENGADGET: Samsung Focus 2 review Mobile