ELECTRON BEAMS :)
Electron Beams :)
What is needed for an electron gun?
- Heater -Cathode -Anode (has a gap in it to channel electrons through, deflecting plates) -Phosphorescent screen
- Conditions: VACUUM so no other particles are hit on the screen
Thermionic Emission: When the heater heats the cathode, this then gives energy to the electrons. Once they have enough energy they 'boil off' i.e. they escape!
How do electron beams work?
1) The heater heats the cathode, which then give more energy to the electrons. The electrons then have enough energy to be attracted and move to the anode. 2) Electrons accelerate are they are pulled towards the positive anode.The anode has a gap in it to channel the electrons through :) 3) An electric field created between charged metal plates can be used to deflect the beam...4) The phosphorescent screen glows when the electrons hit it.