Possible Causes for a Flickering LCD TV Screen
By Dan Stone
A Liquid Crystal Display TV screen may flicker because of a bad video source, a connection problem or a non-optimal lighting condition. Screen flicker is a fluctuation in the picture quality that either displays bright or dark frames intermittently, without actually showing any content on the screen. Note that flicker caused by things other than hardware problems on LCD screens is uncommon.
Flicker in the Video Source
If you're playing back a recording or a live event, flickering in the original video source also displays on your TV set, because the TV displays what it interprets as the correct image. The program or hardware that handles the video conversion can erroneously include bad flicker frames in the actual recording. There's nothing you can do to resolve flickering from a video source.
Cable Connection Problems
HDTVs usually get video input over HDMI, Component or coaxial cable connections, and your LCD TV's screen can drop out and flicker if the cable is damaged or moved in such a way that the connection breaks for a split second. Bent cables may also be damaged in such a way that the video feed comes in at an irregular rate or incomplete, leading to display inconsistencies like flickering. If the flickering only occurs from one video source like a cable fox, antenna, game console or Blu-ray player, try replacing the cables. You may also be able to fix some problems with a cable by disconnecting it, straightening it out using your hands, and then reconnecting it to both devices. If the problem is caused by a bad port, resolve it by using a different connection port on the TV, if available.
Internal Connection Problems
LCD screen flicker can also be caused by a loose or failing connection inside of the television set. The flicker may come from a failing connection ribbon or another electrical component that's near failing. Flickering caused by internal connection problems appears consistently regardless of the video source. You need a trained professional to fix this type of flicker, though such internal issues often indicate that your TV may be near failing and needs to be replaced entirely.
Refresh Rate and Room Brightness
LCD screens are always flickering during use, but the human eye doesn't see fast enough to notice the flickering if the screen updates fast enough. LCD TVs are much less prone to having screen flicker issues than older Cathode Ray Tube, or CRT, screens because LCDs have a higher refresh or update rate, and light the screen more consistently. However, if you're viewing an LCD under a very bright or very dark lighting condition, you may notice your LCD TV's normal screen flicker. Adjusting the screen or room brightness can resolve this type of issue.
Dan Stone started writing professionally in 2006, specializing in education, technology and music. He is a web developer for a communications company and previously worked in television. Stone received a Bachelor of Arts in journalism and a Master of Arts in communication studies from Northern Illinois University.