That solution works for me too.
I have Ubuntu 11.10 and Laptop HP PAVILION DV6
Too make things easier I created a script:
#!/bin/bash
brightness_file=/sys/class/backlight/intel_backlight/brightness
steep=500
current_brightness=`cat /sys/class/backlight/intel_backlight/brightness`
echo current_brightness = $current_brightness
new_brightness=$current_brightness
if [ "$1" = "+" ]
then
new_brightness=`expr $current_brightness + $steep`
fi
if [ "$1" = "-" ]
then
new_brightness=`expr $current_brightness - $steep`
fi
echo new_brightness = $new_brightness
echo $new_brightness | tee $brightness_file
One drawback here you have to open brightness_file for write to anyone:
sudo chmod 666 brightness_file
Then put the script in a file. For example change_brightness.sh
and you can change brightness with commands change_brightness.sh +
or change_brightness.sh -
To make even better you can allocate shortcuts on the same f2 f3 keys.