blank screen

The screen is black . i can.t get it to respond.Power + home soft reset didnt work. Itunes could detect any sync apps. I used my home phone to call my iphone and on my home phone i can hear the calling tone.But my iphone didn't ring/screen did not light up. Its a iphone 4. Any ideas how to fix this?

even i m not getting factory setting after connecting it with pc.