IBM T22 screen is dark is there a bulb that can be replaced?

On most notebooks/laptops the screen are backlit by either a flourescent or LED bulb. You can tell if the backlight has "burned out" by booting the computer and holding the screen up to a bright light at an angle...you should still be able to see things on the screen.

Any local service provider (or even a bright college kid) could replace a screen on one of these for about $200. The college kid might do it for a case of beer. Either way, the parts are relatively cheap and the repair is easy.

hope this helps.

Usually it's the inverter than needs to be replaced and not the bulb (backlight).

Here's some more info here.

Basically you just need to swap the inverter and you're good to go.