This article describes what Pixel Pitch is and how to calculate the Pixel Pitch on an Elo monitor.

Pixel Pitch, also called Dot Pitch, is pixel density calculated as the distance, in millimeters, between the center of 2 pixels on a monitor display. This measurement is calculated from the diagonal length in inches and pixels then converted from inches per pixel to millimeters specified in millimeters (mm).

To calculate pixel pitch, all you need to know is the diagonal screen size in inches and the native screen resolution, then use an online PPI Calculator such as this one from Omni Calculator 

For example: the Pixel Pitch on an Elo ET1902L 19-inch touch monitor with a native resolution of 1280 x 1024  = 0.294mm x 0.294mm