Thin horizontal lines across tv, not dead pixels.

So I was playing a game and suddenly there's just these evenly spaced black lines, horizontal, very thin, evenly spaced from the top to the bottom. They're not just black like dead pixels, there's still some light coming through them, it's just really strange and jarring. Nothing happened to the tv just prior to the lines appearing. I tried resetting the display settings, power cycled, messed around with some more settings and it's still there. I also noticed the lines display across the tv's logo when it starts up, I don't believe it's an HDMI cord issue. I have no idea how to figure out what the issue is because every question I see is usually about pixel failure, and I really don't think that's what's going on here.