Introduction

Don't try this if you haven't experience !!!

How to replace / change broken glass / touch screen - Apple iPad2.

What you need

Use the edge of a plastic opening tool to carefully flip up the retaining flaps on the two digitizer ribbon cable ZIF sockets.
Be sure you are prying up on the hinged retaining flaps, not the sockets themselves.
The retaining flaps are highlighted in red in the second picture.

Use the edge of a plastic opening tool to peel the digitizer cable off the shields on the logic board.
Carefully pull the digitizer cable off the adhesive securing it to the side of the rear case.

Pull the digitizer ribbon cable straight out of its two sockets on the logic board.

In order to remove the front panel assembly, the ribbon cable needs to slide out between the case and the LCD. You'll need to move the LCD to make some room.
Be very careful when moving the LCD, and do not attempt to remove it from the iPad—its cable will remain connected while it is rotated over.
Lift the LCD from its long edge farthest from the digitizer cable and gently flip it toward the rear case—like closing a book.
While holding the LCD up, gently slide the front panel away from the iPad. Be careful not to snag the digitizer cable on the rear case or LCD.
Set the LCD back into the body for safekeeping.