In science we are starting the topic of electricity and have been told to research an item that we used in the school holiday. I choose the TV!
Old TV: A beam of electrons is generated on a filament heated by electricity. A positively charged glass screen attracts the electrons. The screen is coated with chemicals (phosphors) that light up when an electron hits it. Sweeping the beam of electrons over the entire screen (with directing magnets) really quickly lights up the whole screen.
New TV: No beam of electrons, no magnets. Each tiny spot of light that makes up the picture is an actual little solid state light bulb. Rows and columns of these tiny LED’s are scanned one after another. This makes a more efficient TV.
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