My screen is coming on and off?

Hi I have a Samsung phone, I can turn it on and the welcome screen has no problem being displayed, but when it settles as the main screen comes on it goes blank like ive turned the phone off.. however the lights on the keypad stay on??

It cant be called though, and cant call out.

Is this a problem with the ribbon? Or is it the battery? Is this a common problem? I have pictures of my son when he was first born on this phone so I would like to get it fixed if I could.

Thanks for any help, even if it is only to advise me that the phone is rubbish and i need a new one.