windows 10 too bright, windows 10 screen brightness problem

after installing the windows 10, the screen became too bright, before upgraded to windows 10, the windows 7 is perfect.

solution:(might not working for yours)

1. Tap on the Windows-key, type regedit and PRESS enter.
2. Use the left folder structure to navigate to HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\ Themes\Personalize
3. Right-click on Personalize and select New > Dword (32-bit value) from the context menu.
4. Name it SystemUsesLightTheme and make sure it is set to 0.
5. Restart the PC.