Using a plastic opening tool, release the latch (it swings up towards the cable) and slide the digitizer connector free.
On the wide area of the cable (where the chip is), the cable is strongly glued to a small metal plate which is in turn strongly affixed to the back with heat-conducting adhesive. Loosen this cable from the back.
If you plan on reusing the digitizer be very careful when removing this as you can easily damage the cable. Use gentle applications of heat and a metal tool to pry between the metal plate and the back.