screen blank after removed simcard

I removed simcard before turn off the phone... What happened ... The phone turn off automatic... When i turn on again...I heard the sound of turning on but the screen blank.... Black color.... I tried to touch the screen.... Its work..I can open any application but I can see what I touch.... I tried reformat with touch power button n vol up at same time but didn't work... I used torchlight to the screen...I can the display...the icon but very very low brightness until I cannot the icon without torchlight.... Is it security from Sony... What should I do?