After you've taken the shot, there's no good reason not to take the whole thing apart and explore the interior. So that's what we did. A hammer cracked away the rest of the glass, and here's what was inside:
- The front glass - The front glass is an extremely thick, sturdy piece of work. It's actually leaded crystal, like optical glass, to give it great clarity and consistency. The front piece contains between 1 and 2 percent lead.
- The phosphor - On the back of the glass is a phosphor coating. It's a white powder that flakes off.
- The shadow mask - Right behind the screen is the shadow mask. You don't need the mask in a black-and-white TV, but in a color TV, you need it because there are three electron guns and three different colors of phosphor on the screen. At each pixel on the screen, there are tiny dots of red, green and blue phosphor, and the mask makes sure that the right electron gun aligns with the right dot. The most common way to make the shadow mask is to take a thin piece of metal and punch hundreds of thousands of incredibly tiny holes in it.
- The electron gun - At the back of the tube is the electron gun. Once you chip it out, it's a very elegant looking piece of metal and ceramic. Three things happen in the gun: Filaments at the back of the gun heat up to produce the electrons, then the electrons get accelerated, and then they get focused into a tight beam. When the electron beams (three of them in a color TV) leave the electron gun, the electrons are moving at about a third of the speed of light. That gives them enough energy to light up the phosphor when they hit it.
So that's what would happen if you actually shot your television. It's probably not an experiment that you need to repeat, because what you end up with is 50 pounds of leaded glass fragments all over the yard, and it makes a big mess!