Locate the lens head. It is situated near the spindle that rotates the disk. The head looks like the regular lens, only a very small (smaller than the nail on your little finger).
After that, take a dry cotton cosmetic stick and carefully swipe over the lens surface. Do it gently, because the lens is suspended on the coils, which have positioned it during the workflow. And too much push you can damage the precision mechanism. This will cause your player all can stop reading discs.
Use a special cleaning liquid which can be purchased at the hardware store. Apply it on the cosmetic cotton stick and clean as previously cleaned the tape head. Then take a cotton cloth or cloth for wiping glasses and gently wipe dry.
Use cleaning disks. This is one of the options, but the user community is very skeptical about this invention and particularly the use and productivity from such cleaning is not watching. But as they say, if such a case exists, so not so bad, and they all work. However, there is one "but". Cleaning disc, whatever it was good, will be able to remove the contamination from the surface, and under the head will be a pile of dust.
Use "joint" cleaning. For a start run a special cleaning disc that will clean contamination from the surface of the dvd-head, and then disassemble the player and clean the remaining contaminated area manually. Thus, you need not worry about damage to the surface of the lens head, if, say, the hand trembled. Spend such a thorough cleaning from time to time. For example, every few months. Do not wait to start "jumping" or other interference during playback.