What is a cathode ray tube and how does it work?
We’ll have things ahead of the control grid that will focus the beam, and then we’ll use one of two basic methods to “direct” or “aim” or “sweep” the beam (magnetic or electrostatic deflection). Think of the beam as a pencil of light writing on the front of the tube. It writes very quickly by scanning across in a line, turning off and “retracing” to get back to the othere side, and then scanning another line below the last one. The beam is turned on and off (modulated) a little, a lot, or something in between as it sweeps. It paints an image of some kind by scanning all the lines. Then it repeats. This is the basic operation of the cathode ray tube. You’ll want a link to do some follow up, and you can find one below.
