I have a Dell 15" color monitor that is 2-3 years old. Can't find paperwork & don't know the type of monitor it is (large, bulky.

If it is large and bulky, it is CRT (Cathode Ray Tube) type. These can be either shadow mask or aperture grill type. The monitor specifications may list the type, otherwise aperture grills tend to have a visible horizontal line approximately a third and possibly two thirds of the way up the screen.

If you were referring to some other "type", post back.