Laptop display. Laptop displays don't have brightness or contrast buttons on the front. For a majority of laptops, there isn't a control for setting the contrast. However, you can set the brightness of many laptops by pressing and holding the Fn key, and then pressing a function key to decrease brightness (Picture of the Decrease brightness button) or increase brightness (Picture of the Increase brightness button). When using Display Color Calibration on a laptop, set the display to the maximum brightness setting.