i don't think that you can do that.
To adjust brightness in ubuntu Open a terminal window, and execute this command to edit /etc/rc.local
sudo nano /etc/rc.local
Add this before the last line “exit 0″:
echo 10 > /sys/class/backlight/acpi_video0/brightness
number 10 is the value of your screen brightness of your choice, range from 1 to 10 or 15. With this command check the maximum:
And also one more way we have to do this is with another new program named as xbacklight open your terminal and type this
sudo apt-get install xbacklight
then type this
xbacklight -set 100
there 100 stands for brightness range we can get it upto 100 from 0 .
But i didn't try it.