How to fix black screen?

Hi,

If anyone has any ideas about my iPad, then I would be grateful. I bought the iPad extremely cheaply from a friend who had bought a new one and had no need for the old one. The screen is always completely black, although when the power button is pressed the display is back lit, but still black. I have tried a hard reset, nothing, still black, not even showing apple logo. I have tried updating and restoring, putting in recovery more, none work, the screen is never showing anything other than black. What steps should I try now, and if the problem is hardware, does anybody have any idea what component would cause the screen to be constantly black?

Thanks for reading,

Michael