3007WFP-HC, diagnosing uniformity issues

Hello all,

I have a Dell 3007WFP-HC that's had better days. The uniformity of the display has become extremely poor in a way that's fairly difficult to describe, so I've attached pictures below. I understand that Dell doesn't repair monitors, but it would be great to know what the problem is, what caused it, and whether/how it can be salvaged. I'm an electronics engineer, so if it's fixable I'd be keen to have a go at it myself.

Thank you!