Black streaks in the screen there is a black streak on the right side of the screen

Inspect where the dark streaks are on the television. If the streaks occur at the same place on the top and bottom of the screen, they are due to the formatting of a movie or television show you are watching. This is normal. Also, if the streaks appear on the left and right of the screen, they are due to the show being filmed in full-screen instead of wide-screen. This also is normal.

Change the input setting so you are viewing the contents of a different device. If the dark streaks are gone, you know they are due to the device connected to it. However, if the dark streaks remains no matter what input the TV is connected to, the problem lies with the television.