Adjusting brightness in Windows 7
*Open the Control Panel.
*Select Hardware and Sound.
*Select Power Options.
*Use your mouse to move the brightness slider at the bottom of the window.
Windows 10
In Windows 10, there are several ways to adjust the display brightness.
*Using the taskbar's battery icon
*Using the Windows Mobility Center
*Using the Control Panel
*Using the taskbar's battery icon
*Click the battery icon on your taskbar.
*In the power status window, click the brightness tile. Each time you click the tile, your brightness will be adjusted by 25%.