Lenovo ThinkPads have built-in functions that allow you to adjust various settings on the monitor, such as brightness. All of these functions can be found in the Control Panel or by right-clicking on the desktop. Lenovo ThinkPads however, like many laptops, have keys on the keyboard that serve double duty. These extra functions are shown on the key in blue. Just like you would use the shift key to access the special characters above the numbers, you use the blue "Fn" key in the lower left corner to access these special functions. Brightness control functions are two of these keys.
Examine the keyboard and locate the blue "Fn" button and all of the keys that have a function identified by a blue symbol. Most of these are small ideograms that represent a function. Some of these are obvious, while others will require looking at the manual to identify what they do.
Find the keys for the monitor's brightness control. These are located toward the upper right corner. The key to increase brightness is shared with the "Home" key. The key to decrease brightness is shared with the "End" key, just below it.
Press the blue "Fn" key, and while holding it down, press either the "Home" or "End" key. When you do, you will see a green graphic display appear on the screen showing a slider that represents where on the brightness scale you are and what happens with each key press. When you are satisfied with the brightness, release the "Fn" key.