Thin, horizontal lines on right half of screen

[bpizzle1]

The TV I'm using with my HTPC has suddenly developed these lines. It only affects the right half of the screen. I don't think it's the HTPC since the lines also appear on the the TV menus. Any idea what could be causing this? It almost seems like lines dividing pixels or something.

Here's a crappy pic I took with my phone. The host keeps rotating the pic for whatever reason, so the lines I'm talking about appear vertical in the pic, but are actually horizontal.