If you use a Windows computer or if you prefer portable versions of Windows, to adjust your screen brightness level you need to:
Download and run the special Night Mode for Windows installer 
As with all programs, enjoy the benefits of use: you’ll be pleased with the main advantage of this little utility: the settings are stored in the registry for easy access. No disk space requirements, no installation procedure.
To start with Night Mode for Windows, click here to download it 6add127376