First of all, you always need to keep in mind that LCD screen is not glass. Do not clean it as if it is a glass screen. It’s a big mistake. LCD means liquid crystal display and such a type of a screen consists of a soft film that can be easily damaged by using improper cleaner or cloth.
There is one big problem of LCD screens, they regularly gather dust and fingerprints. Many people make a big mistake when they take a usual paper or usual cloth and tap water. Never do it!
LCD screens should be cleaned with a microfiber cloth that will help to remove dust.
Prepare a 50 to 50 solution of distilled water and isopropyl alcohol.
There are also many cleaning products for LCD screens that are sold at the stores. Of course, you may use them. But never spray this product directly on a screen, spray it on a cloth and them gently wipe the surface of the screen.
Before you switch it back let it dry thoroughly.
Now you can enjoy your LCD TV again!