Is my 42PX60 about to expire?

[hornetrider]

Not had any problems before seeing this fault, but basically when I switch it on it'll flicker and I'll see an almost screen burned negative image for a varying amount of time - anywhere from a few seconds to several minutes. It started this behaviour a couple of months ago and is getting worse, and now it's just started to do it every so often after being fully warmed up.

I don't know if this is a simple repair or bin and replace job. Ideas?