Software :: Is There Way To Control LCD's Fluorescent Light's Power?

To protect my eyes I always lower the monitor's brightness to its lowest. In some of the computers/displays I can get the desired low brightness in some others I cannot. For example in my WinXP ThinkPad R51 laptop I can make the brightness extremely low while in Ubuntu 9.04 ThinkPad R41 laptop and Apple Mac mini/23" Cinema Display I cannot get the desired lowness easily.

But in my Ubuntu 9.04 ThinkPad laptop, just as the energy saving routine has started to dim the brightness of LCD, an idea has come up. The energy saver routine was apparently lowering the fluorescent light's power, I'm sure of it. So I wonder now if there's a way to control and set that by myself? I'd like to set the fluorescent light's power to a much lower level.