In other words, how many pixels per inch depends on the size and resolution of the screen you're talking about, so we'll have to do some math to get the number you're after for yours. Related ...

The number of horizontal and vertical pixels on a display screen. The more pixels, the more information is visible without scrolling. Screen resolutions have a pixel count such as 1600x1200 ...

This metric is based on a combination of the device's screen resolution and its physical size. The iPhone 4 had 326 PPI due to a 3.5-inch screen with a 960-by-640 resolution. This spec was the ...

Resolution-wise you're ... Part of Lenovo's logic for the expanding screen is that it enables people to use a 16.7-inch display on a computer that's the size of a 14-inch laptop.