If you are unhappy with default backlight brightness regulation of your Intel graphics-based laptop (too bright at lowest level and burn your eyes at night), you can try this script.
Install intel-gpu-tools:
sudo apt-get install intel-gpu-tools
Make sure script intel_custom_backlight.sh is executable:
chmod +x intel_custom_backlight.sh
Put this file to /usr/local/sbin
In GNOME Keyboard Shortcuts create bindings "Backlight Up" and "Backlight Down", set commands respectively:
sudo intel_custom_backlight.sh up
sudo intel_custom_backlight.sh down
and bind any key combination you want (I choose Fn+Alt+Brightness Up and Fn+Alt+Brightness Down).
Tested on Acer Aspire V5-573G (i3-4010u, HD4400) + Ubuntu 18.04