To adjust the brightness:
Use the system power option to adjust the screen brightness.
Scope of application: Windows 8. 1, Windows 8, Windows 7, Windows Vista (note: Windows XP system does not support it).
1. Locate the power status icon in the lower right corner of the taskbar, and then click it. Click Adjust Screen Brightness in the pop-up screen. As shown in the figure:
2. In the pop-up power options window, drag the slider of "screen brightness" at the bottom with the left mouse button to adjust. As shown in the figure: