increasing brightness on LXDE display on lubunut

LXDE seems to have 2 brightness controls. Both of them are found in locations: /sys/class/backlight/

For me it was :

harsshal@dell:~$ ll /sys/class/backlight/ 

lrwxrwxrwx  1 root root 0 Mar 18 12:58 acpi_video0 -> ../../devices/pci0000:00/0000:00:02.0/backlight/acpi_video0/lrwxrwxrwx  1 root root 0 Mar 18 12:58 intel_backlight -> ../../devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight/

Both locations have max_brightness file :

harsshal@dell:~$ ll /sys/class/backlight/*/max_brightness -r--r--r-- 1 root root 4096 Mar 18 12:58 /sys/class/backlight/acpi_video0/max_brightness-r--r--r-- 1 root root 4096 Mar 18 12:58 /sys/class/backlight/intel_backlight/max_brightness

harsshal@dell:~$ cat /sys/class/backlight/*/max_brightness 7255000

So typically intel_backlight will be controlled by all your default brightness controller, but acpi_video0 will need manual changes when you need to change it:

harsshal@dell:~$ echo 7 | sudo tee /sys/class/backlight/acpi_video0/brightness 7

Other methods of increasing brightness :

harsshal@dell:~$ xbacklight -set 60

Or

harsshal@dell:~$ xrandr -q | grep -w connectedLVDS-1 connected 1280x800+0+0 (normal left inverted right x axis y axis) 290mm x 180mmharsshal@dell:~$ xrandr --output LVDS-1 --brightness 1