In order to get a good light distribution, we need to select the right shade on a table or floor lamp. A shade spreads the amount of light given by a bulb in a certain way.

The wider the botton of the shade, the bigger the light spread it gets. A shade that is too narrow can keep the light from reaching the entire area you want to iluminate. On the other side a shade that is to wide can spread the light too far.

To adjust 2 inches in the diameter of the shade can make a noticeable difference in the light spread.

We have to pay attention to the bulb as well. A tall bulb will cause the filament to be positioned higher in the shade than a smaller one, reducing the light spread from the bottom of the shade. This problem can be solve by raising the shade or the bulb.