Power Button fixed - now screen problem - backlight working

Hi

I fixed the power button problem but now my screen has a problem.

Ipod is working via mac, back light is on but nothing else is shown.

A photo of the screen is at the copied link.

https://www.dropbox.com/s/tusdjep8xy2gez...

Do I just have to buy a new screen or did I break something serious while fixing the power button?

Thanks