I recently carried out an experiment to help determine which company manufactures the strongest glass digitizer screens. My test: I shot the screens with a cheap BB Gun. The first round was with the screen taped to a wall. The next was in a box with no backing. At the end, I just repeatedly tried to smash the screen on the corner of a desk. Like I said, this was really scientific.
Source: http://www.technewsworld.com/rsstory/73201.html
HYNIX SEMICONDUCTOR INFOSYS TECHNOLOGIES INTERNATIONAL BUSINESS MACHINES INVENTEC