I have horizontal lines through the screen

I have horizontal lines through the screen

I have lines through the screen that are there when first turned on but after about 20 minutes they go away. what is the issue?

ANSWERS:

Sounds like the screen is going bad. How old is the TV? If its less than a year old contact Samsung about it. If its more than a year old you could still try to contact them however they may not help you, which means you would have to get a new TV. Is there a warranty on it?