02 April 2009

The effects of magnets on a television screen


You can enjoy and appreciate this video; for your children this will be meaningless, because the science behind the experiment will be irrelevant with digital television.
Because the picture is formed by steering the charges with the electromagnetic coils, any additional external field in the nearby vicinity is going to alter the field between the coils. This is going to affect the electron deflection, resulting in a distorted, fun-house-esque picture on the screen. It's also important to note that a strong enough magnet can permanently magnetize the copper coils resulting in a permanently distorted picture. Bear that in mind if you ever try this at home.

2 comments:

  1. In the arcade industry we use a special device called degausing coil, which is a circular ring approximately a foot and a half wide that plugs into the wall. When you activate it and point it at a cathode ray tube monitor, is projects a magnetic field which disrupts the electromagentic flux and deflection. By moving the degausing coil around the screen, you can correct any coloration flaws that might have occurred through exposure to large magnets.

    Contrary to arcade myth, one does not have to point the game to the north in order to degauss a screen. :)

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  2. Of course, it should be noted that these rare earth magnets can also seriously lobotomize a computer or external hard drive.

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