TheOriginal FatDonkey's video: How Stuff works CRT Cathode Ray Tubes Televisions FOCUSED ELECTRON BEAM

CRT's use a property called focused electron beam tube, glass shell vacuum(tube) an electron gun, causes the electrons to go through the cathode to the anode in between these there are a grid charging ring, hole in the grid, phosphorus, and shadow mask is basically what makes yo your focused electron beam controllable.Raster is controlled by the system clock RTC module and its responsible for scrolling teh electron gun across the screen 15,734 times a second and vertically 59.94 times a second, the ZET or Z axis controls the brightness to the spot in a CRT, These same principals are why we have CRT, LCD, LED tv's etc. Raster is where all TV's come in. Behind the faceplate there is a shadow mask.