This is not duplicate of https://superuser.com/questions/560445/dim-screen-past-the-minimum-on-ubuntu . I have already tried the solution mentioned in the above article. my laptop configuration is dell inspiron 1440. I wanted to reduce my laptop screeen brightness in ubuntu below the minimum level that can be set using system settings. I usually set my screen brightness to an ultra low level, as it hurts my eyes. I have already searched for the solution online and found related posts
https://superuser.com/questions/323476/can-i-fine-tune-my-screen-brightness
Decrease Backlight Below Minimum
https://superuser.com/questions/560445/dim-screen-past-the-minimum-on-ubuntu
Decrease Backlight Below Minimum
The problem is that in my case the screen brightness value in the file /sys/class/backlight/acpi_video0/brightness is already 0. I have tried installing backlight and setting it to 0, and overwriting the value again as described in one of the posts above. However, none of it helps. I am currently using the latest version of ubuntu 13.10 . Any help is highly appreciated. Thanks,